Krzysztof Pawlicki

Daily and circadian rhythms in the activity of mixed function oxidases system in rats of different age

Abstract An age‐associated alterations in daily and circadian changes of cytochrome P‐450‐linked monooxygenases system activity were studied using 1‐, 6‐ and 12‐months old male Wistar rats, in winter and in spring season. Cytochrome P‐450 and NADPH‐cytochrome P‐450 reductase showed 12h rhythm in all investigated age groups of animals. Cytochrome b5 and NADH‐cytochrome b5 reductase were characterized by a 12h daily rhythm in 1‐month old rats, but in older ones 24h circadian rhythm was found. There was not significant changes of the rhythm pattern in the activity of investigated MFO system ingredients in rats of different age, between spring and winter.

Endothelium injury and inflammatory state during abdominal aortic aneurysm surgery: scrutinizing the very early and minute injurious effects using endothelial markers – a pilot study

Introduction One of the most severe complications of repair surgery for abdominal aortic aneurysms (AAA) is acute kidney injury (AKI). Acute kidney injury is an inflammatory process whose pathogenesis involves endothelial cells (EC). The aim of this study was to assess the dynamics of endothelium injury markers measured during elective AAA surgery which might confirm the inflammatory character of AKI. Material and methods The study group consisted of 14 patients with AAA. We measured plasma soluble forms of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, P-selectin as well as the levels of von Willebrand factor (vWF) before, during (including intra-abdominal vein levels before and after aortic clamp removal) and within 2 days after surgery. Results We have found a biphasic response of ICAM-1, VCAM-1 and P-selectin with an initial fall and subsequent rise. However, only VCAM-1 changes were significant compared to its baseline value. The maximum decrease of VCAM-1 was observed in the renal vein 5 min after aortic clamp removal (335.42 ±129.63 ng/ml vs. 488.90 ±169.80 ng/ml baseline value, p < 0.05), and the highest rise 48 h after aortic clamp removal (721.46 ±333.99 vs. baseline, p < 0.05). Conclusions Vascular cell adhesion molecule-1 turned out to be the most sensitive indicator of EC injury and inflammatory status after AAA surgery. During AAA surgery, soluble forms of P-selectin, ICAM-1 and VCAM-1 demonstrate a biphasic response with an initial fall and subsequent rise. These soluble forms could have a modulatory effect on the development of inflammation.

Assessment of subclinical acute kidney injury after abdominal aortic aneurysm surgery using novel markers: L-FABP and H-FABP

BACKGROUND One of the most severe complications of repair surgery for abdominal aortic aneurysms (AAA) is acute kidney injury (AKI). Even small rises in serum creatinine are associated with increased mortality. The aim of this study was to assess the dynamics of AKI after elective AAA surgery using novel markers. METHODS The study group consisted of 22 patients with AAA. We measured urinary liver- (u-L-FABP) and heart-type fatty acid-binding proteins (u-H-FABP) before, during and within 3 days after surgery. RESULTS We found an abrupt and significant elevation of both urine FABPs normalized to urinary creatinine; u-L-FABP reached its peak value 2 hours after aortic clamp release {137.79 (38.57-451.79) vs. 9.94 (6.82-12.42) ng/mg baseline value, p<0.05; values are medians (lower-upper quartile)}. The peak value of u-H-FABP was reported 72 hours after aortic clamp release {16.462 (4.182-37.595) vs. 0.141 (0.014-0.927) ng/mg baseline value, p<0.05}. The serum creatinine level did not changed significantly during the investigation period. CONCLUSIONS The significant rise of both u-L-FABP and u-H-FABP after AAA surgery indicates renal proximal and distal tubule injury in this population. Our results suggest that, after AAA surgery, the distal tubules could be more affected than the proximal ones. u-FABPs could serve as sensitive biomarkers of kidney tubular injury and may allow to detect the very early phases of AKI.

Platelet reactivity in thromboelastometry. Revision of the FIBTEM test: a basic study

Abstract This study aimed to investigate modifications to the FIBTEM test to better assess fibrinogen levels and the quality of fibrin polymerization in citrated blood using Multiplate impedance aggregometry to verify platelet inhibition. Blood samples from 26 healthy volunteers were subjected to thromboelastometry studies (EXTEM/FIBTEM tests) in accordance with the standard study protocol (cytochalasin D) and according to a modified protocol (synthetic IIbIIIa receptor antagonist vs. acetylsalicylic acid [ASA] + synthetic IIbIIIa receptor antagonist instead of cytochalasin D). Independent of thromboelastometry, Multiplate impedance aggregometry was used to assess the degree of restriction by the platelet blocked with the following treatments: (1) cytochalasin D, (2) synthetic IIbIIIa antagonist or (3) ASA + synthetic IIbIIIa antagonist to assess the aggregation response to activation with an agonist (ADP, collagen, thrombin receptor activating peptide-6 [TRAP-6], and arachidonic acid). Via aggregometry, cytochalasin D more weakly inhibited platelet aggregation than simultaneous administration of the -IIbIIIa receptor antagonist with ASA. However, total platelet aggregation inhibition was observed after simultaneous administration of cytochalasin D combined with a synthetic IIbIIIa receptor antagonist. In the thromboelastometry, a significant decrease of the A10, A20 and MCF parameters were observed in the EXTEM/FIBTEM tests after they were modified by the addition of a synthetic IIbIIIa receptor antagonist alone or in combination with ASA. In conclusion, in this Multiplate- and ROTEM-based laboratory approach, a two-way blockade (IIbIIIa-antagonist + cytochalasine D) was sufficient to completely inhibit procoagulant platelet function as observed by aggregometry and thromboelastometry.

Associations Between Nutritional Parameters and Clinicopathologic Factors in Patients with Gastric Cancer: A Comprehensive Study

ABSTRACT The aim of this study was to assess and analyze the nutritional status of gastric cancer (GC) patients. The analysis included 207 patients with GC treated in a large center of oncology. Patients were divided into two groups according to the cutoff value of the mean prognostic nutritional index (PNI): those with a PNI < 52.78 and those with a PNI ≥ 52.78. The higher PNI was associated with lower age and higher total protein and hemoglobin levels (P < 0.01). The total lymphocyte count (P = 0.02), albumin, total protein and PNI (P < 0.01) were significantly higher in stable-weight patients and lower in the group with weight loss > 10% (P = 0.000031). Body mass index (BMI) after disease recognition, albumin and total protein (0.003) levels, total lymphocyte count, and PNI were significantly lower in patients with nutritional risk. Significantly lower BMI before disease and BMI after disease recognition were noted in smoking patients. Significantly higher total lymphocyte count was observed in smoking patients (P < 0.01). Significantly lower PNI was noted in tumors with lymph node metastasis (N+). G3 tumors were associated with the lowest total lymphocyte count (P = 0.01). Assessment of nutritional status using PNI calculation should be the standard management of patients with GC before treatment.

Intraluminal thrombus thickness is not related to lower concentrations of trace elements in the wall of infrarenal abdominal aortic aneurysms

BACKGROUND Intraluminal thrombus (ILT) formation plays a significant role in the progression of infrarenal abdominal aortic aneurysms (AAA). Potentially, as ILT thickness increases the availability of trace elements in the aneurysm wall could decrease thereby leading to oxidative stress and intensifying pro-inflammatory cytokine generation. AIM To determine if thrombus thickness is related to the concentration of trace elements in the wall of infrarenal AAA. PATIENTS AND METHODS The concentrations of trace elements in the wall of the aneurysm sack and ILT obtained from 19 consecutive patients during surgery for infrarenal AAA were determined using emission spectrometry. RESULTS The concentrations of magnesium, zinc, manganese, and lead in the wall of AAA were significantly greater than in the ILT. Only the concentration of copper was lower in the AAA wall compared with the thrombus. The concentration of calcium, phosphorus, zinc, lead, copper, and magnesium increased with ILT thickness. The concentrations of no other trace elements in the wall of AAA were found to be related to the ILT thickness. CONCLUSIONS Intraluminal thrombus thickness is not associated with a lower concentration of trace elements in the wall of the infrarenal AAA. Thus, the intraluminal thrombus participates in the progression of AAA by mechanisms independent of trace element supply to the wall of the aneurysm sack.

Evaluation of metformin therapy using controlled attenuation parameter and transient elastography in patients with non-alcoholic fatty liver disease

BACKGROUND Non-alcoholic fatty liver disease (NAFLD) is among the most common causes of liver disease worldwide. There is growing evidence on pathogenesis and pathophysiology of NAFLD. However, there is still no universally accepted pharmacotherapy protocol. METHODS The study was conducted on 42 patients with NAFLD. They were randomized to dietary treatment alone (n = 21) or to diet and metformin therapy (n = 21). Liver ultrasonography, controlled attenuation parameter (CAP), liver stiffness (LS), complete blood count, anthropometric and biochemical parameters were obtained before treatment (baseline), and after 3 and 5 months of the therapy. RESULTS Patients treated with diet and metformin exhibited significantly decreased CAP values at 3 and 5 months of the therapy compared to baseline (319 dB/m vs. 285 dB/m; p < 0.05; 319 dB/m vs. 295 dB/m; p < 0.05 respectively). Five months of diet and the metformin therapy resulted in significant reduction of LS value (6.2 kPa vs. 5.2 kPa; p <  0.05), while patients treated with diet alone had no significant changes in liver CAP and LS measurements. CONCLUSIONS Metformin therapy combined with dietary treatment seems to be effective for the reduction of hepatic steatosis and fibrosis. However, considering limitations of the study and inconsistent results of previous investigations in this area, there is a need for further research on metformin efficacy in this group of patients.

Histopathological Evaluation of a Hydrophobic Terpolymer (PTFE-PVD-PP) as an Implant Material for Nonpenetrating Very Deep Sclerectomy.

PURPOSE The purpose of the study was to assess the biocompatibility of porous terpolymer (polytetrafluoroethylene-co-polyvinylidene fluoride-co-polypropylene, PTFE-PVDF-PP) membranes as an implant material to be placed during nonpenetrating very deep sclerectomy (NPVDS). Another study objective was to determine whether the polymer membrane under investigation could be used to manufacture a new-generation implant, which would actively delay the process of fistula closure and facilitate aqueous humor drainage. METHODS Histological response and tissue tolerance of the implant material were assessed. The study was performed on 38 eyeballs of 19 New Zealand white rabbits (19 implanted, 19 control). Histological assessment was carried out between 2 and 52 weeks after surgery. We routinely assessed inflammatory infiltrate, neovascularization, hemorrhage, and stromal edema as well as connective tissue attachment to the implant and adjacent tissues. RESULTS At 52 weeks of observation, a statistically significant difference was revealed between the study and control groups in terms of resorptive granulation, tissue, and the inflammatory infiltrate. No features of acute inflammatory response to the implant were observed, and there was an absence of histological features of acute inflammatory infiltrates and subsidence of chronic inflammatory infiltrates and resorptive granulation over time. CONCLUSIONS Slight fibrotic response and insignificant changes in neighboring eye tissues all indicate good tolerance to bioimplant materials. This allows for some optimism regarding the use of hydrophobic terpolymer in the construction of new intrascleral implants. However, the ultimate decision regarding its usefulness and safety in the treatment of glaucoma requires further investigation.

Trace elements in the wall of abdominal aortic aneurysms with and without coexisting iliac artery aneurysms.

Iliac artery aneurysms (IAA) and abdominal aortic aneurysms (AAA) frequently coexist. It remains unknown whether the content of trace elements in AAA walls depends on the coexistence of IAAs. The aim of this study was to compare the content of selected trace elements in AAA walls depending on the coexistence of IAAs. The content of trace elements was assessed in samples of AAA walls harvested intraoperatively in 19 consecutive patients. In the studied group, coexisting IAAs were diagnosed in 11 out of the 19 patients with AAA. The coexistence of IAAs was associated with a slightly lower content of nickel (0.28 (0.15–0.40) vs. 0.32 (0–0.85) mg/g; p = 0.09) and a significantly higher content of cadmium (0.71 (0.26–1.17) vs. 0.25 (0.20–0.31) mg/g; p = 0.04) in AAA walls. The levels of the remaining studied elements, copper, zinc, manganese, magnesium and calcium, were comparable. The elevated levels of cadmium in the walls of AAA coexisting with IAAs may suggest an impact of the accumulation of this trace element on the greater damage of the iliac artery wall.

Non-penetrating very deep sclerectomy with a hydrophobic polymer implant in a rabbit model

PURPOSE The aim of the study was to evaluate the influence of an implant made of a terpolymer (PTFE-PVDF-PP) on the condition of rabbit eyes during a one year observation period. METHODS The implant in the shape of an equilateral triangle (3 mm side length) was manufactured from a thin hydrophobic porous membrane. There were evaluated 40 eyes of 20 rabbits. The animals had non-penetrating very deep sclerectomy (NPVDS) performed, with insertion of an implant in the form of a triangular thin membrane. The control group consisted of 20 eyes where the animals had NPVDS performed without implant insertion. The evaluations included the study of the anterior part of the eye together with photographic documentation. Histopathological examination of the eyes 52 weeks after NPVDS procedure has been made. The process of wound healing was comparable in both groups. RESULTS The evaluation of the rabbits did not reveal any acute process of intraocular inflammation. After 12 month period of observation, no statistically significant differences in the process of wound healing or status of eyes were found between the groups. An analysis of fibrous connective tissue attachment to the implant showed that its layer was not thick and did not differ significantly from the control. The procedure of very deep sclerectomy and insertion of a polymer implant were well tolerated by the rabbit eyes. CONCLUSIONS The in vivo results indicate that the hydrophobic implant in the form of a membrane can serve as a sclera implant after further study.