Bartlomiej Perek

Prof. Bartlomiej Perek

Department of Cardiac Surgery and Transplantology, Poznan University of Medical Sciences, 61-848 Poznan, Poland
orcid

Research Focus & Metrics

Academic Career Length

29Years (1998-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
26 March 2022 in Cells
Verified
Journal Article
Open access
PDF file
Tomasz UrbanowiczTomasz Urbanowicz
Tomasz Urbanowicz
MMMichał Michalak
Michał Michalak
AOAnna Olasińska-Wiśniewska
Anna Olasińska-Wiśniewska
MRMichal Rodzki
Michal Rodzki
AWAnna Witkowska
Anna Witkowska
MJMarek Jemielity
Marek Jemielity
Background: Several perioperative inflammatory markers are postulated to be significant factors for long-term survival after off-pump coronary artery bypass surgery (OPCAB). Hematological parameters, whether single or combined as indices, provide higher predictive values. Methods: The study group comprised 538 consecutive patients (125 (23%) females and 413 (77%) males) with a mean age of 65 ± 9 years, who underwent OPCAB with a mean follow-up time of 4.7 ± 1.7 years. This single-center retrospective analysis included perioperative inflammatory markers such as the neutrophil-to-lymphocyte ratio (NLR), systemic inflammatory response index (SIRI), aggregate index of systemic inflammation (AISI), and systemic inflammatory index (SII). Results: Multivariable analysis identified levels of neutrophils above 4.3 × 109/L (HR 13.44, 95% CI 1.05–3.68, p = 0.037), values of SIRI above 5.4 (HR 0.29, 95% CI 0.09–0.92, p = 0.036) and values of NLR above 3.5 (HR 2.21, 95% CI 1.48–3.32, p < 0.001) as being significant predictors of long-term mortality. The multifactorial models revealed the possibility of strong prediction by combining preoperative factors (COPD, stroke, PAD, and preoperative PLR) and postoperative neutrophil counts (p = 0.0136) or NLR (p = 0.0136) or SIRI (p = 0.0136). Conclusions: Among the postoperative inflammatory indices, the levels of neutrophils, NLR, and SIRI are the most prominent markers for long-term survival after off-pump coronary artery bypass surgery, when combined with preoperative characteristics.

Verified
Journal Article
Open access
PDF file
GHGreg Hutchings
Greg Hutchings
KJKrzysztof Janowicz
Krzysztof Janowicz
LMLisa Moncrieff
Lisa Moncrieff
CDClaudia Dompe
Claudia Dompe
ESEwa Strauss
Ewa Strauss
Michał NowickiMichał Nowicki
Michał Nowicki
Neovascularization and angiogenesis are vital processes in the repair of damaged tissue, creating new blood vessel networks and increasing oxygen and nutrient supply for regeneration. The importance of Adipose-derived Mesenchymal Stem Cells (ASCs) contained in the adipose tissue surrounding blood vessel networks to these processes remains unknown and the exact mechanisms responsible for directing adipogenic cell fate remain to be discovered. As adipose tissue contains a heterogenous population of partially differentiated cells of adipocyte lineage; tissue repair, angiogenesis and neovascularization may be closely linked to the function of ASCs in a complex relationship. This review aims to investigate the link between ASCs and angiogenesis/neovascularization, with references to current studies. The molecular mechanisms of these processes, as well as ASC differentiation and proliferation are described in detail. ASCs may differentiate into endothelial cells during neovascularization; however, recent clinical trials have suggested that ASCs may also stimulate angiogenesis and neovascularization indirectly through the release of paracrine factors.

27 May 2021 in Vaccines
Verified
Journal Article
Open access
PDF file
Piotr RzymskiPiotr Rzymski
Piotr Rzymski
BPBartlomiej Perek
Bartlomiej Perek
Robert FlisiakRobert Flisiak
Robert Flisiak
The rollout of COVID-19 vaccines brings hope for successful pandemic mitigation and getting the transmission of SARS-CoV-2 under control. The vaccines authorized in Europe displayed a good safety profile in the clinical trials. However, during their post-authorization use, unusual thrombotic events associated with thrombocytopenia have rarely been reported for vector vaccines. This led to the temporary suspension of the AZD1222 vaccine (Oxford/AstraZeneca) in various European countries and the Ad26.COV2 vaccine (Janssen/Johnson&Johnson) in the United States, with regulatory bodies launching investigations into potential causal associations. The thromboembolic reactions were also rarely reported after mRNA vaccines. The exact cause of these adverse effects remains to be elucidated. The present paper outlines the hypotheses on the mechanisms behind the very rare thrombotic thrombocytopenia reported after the COVID-19 vaccination, along with currently existing evidence and future research prospects. The following are discussed: (i) the role of antibodies against platelet factor 4 (PF4), (ii) the direct interaction between adenoviral vector and platelets, (iii) the cross-reactivity of antibodies against SARS-CoV-2 spike protein with PF4, (iv) cross-reactivity of anti-adenovirus antibodies and PF4, (v) interaction between spike protein and platelets, (vi) the platelet expression of spike protein and subsequent immune response, and (vii) the platelet expression of other adenoviral proteins and subsequent reactions. It is also plausible that thrombotic thrombocytopenia after the COVID-19 vaccine is multifactorial. The elucidation of the causes of these adverse events is pivotal in taking precautionary measures and managing vaccine hesitancy. It needs to be stressed, however, that the reported cases are currently sporadic and that the benefits of COVID-19 vaccines vastly outweigh their potential risks.

27 December 2021 in Biology
Verified
Journal Article
Open access
PDF file
Tomasz UrbanowiczTomasz Urbanowicz
Tomasz Urbanowicz
AOAnna Olasińska-Wiśniewska
Anna Olasińska-Wiśniewska
MMMichał Michalak
Michał Michalak
MRMichal Rodzki
Michal Rodzki
AWAnna Witkowska
Anna Witkowska
MJMarek Jemielity
Marek Jemielity
Background: Cardiovascular diseases, apart from commonly known risk factors, are related to inflammation. There are several simple novel markers proposed to present the relation between inflammatory reactions activation and atherosclerotic changes. They are easily available from whole blood count and include neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), and platelets to lymphocyte ratio (PLR). The RDW results were excluded from the analysis. Method and results: The study based on retrospective single-centre analysis of 682 consecutive patients (131 (19%) females and 551 (81%) males) with median age of 66 years (60–71) who underwent off-pump coronary artery bypass grafting (OPCAB) procedure. During the median 5.3 +/− 1.9 years follow-up, there was a 87% cumulative survival rate. The laboratory parameters including preoperative MLR > 0.2 (HR 2.46, 95% CI 1.33–4.55, p = 0.004) and postoperative NLR > 3.5 (HR 1.75, 95% CI 1.09–2.79, p = 0.019) were found significant for long-term mortality prediction in multivariable analysis. Conclusion: Hematological indices NLR and MLR can be regarded as significant predictors of all-cause long-term mortality after OPCAB revascularization. Multivariable analysis revealed preoperative values of MLR > 0.2 and postoperative values of NLR > 3.5 as simple, reliable factors which may be applied into clinical practice for meticulous postoperative monitoring of patients in higher risk of worse prognosis.

4 March 2022 in Diagnostics
Verified
Journal Article
Open access
PDF file
Tomasz UrbanowiczTomasz Urbanowicz
Tomasz Urbanowicz
MMMichał Michalak
Michał Michalak
Ahmed Mohammed-Lutfi Al-ImamAhmed Mohammed-Lutfi Al-Imam
Ahmed Mohammed-Lutfi Al-Imam
AOAnna Olasińska-Wiśniewska
Anna Olasińska-Wiśniewska
MRMichal Rodzki
Michal Rodzki
MJMarek Jemielity
Marek Jemielity
Diabetes mellitus (DM) represents a complex carbohydrate metabolism disorder characterized by inflammatory over-reactivity. The study aimed to investigate the potential influence of postoperative inflammatory activation on mortality risk after off-pump coronary artery bypass grafting in diabetic patients. There were 510 patients treated with off-pump coronary artery bypass grafting due to stable complex coronary artery disease, including 175 patients with type-2 DM (T2DM.) The mean follow-up time was 3.7 +/− 1.5 years with a 9% all-cause mortality rate in the diabetic group. In multivariable analysis, preoperative comorbidities (stroke, peripheral artery disease, postoperative systemic inflammatory index >952, and postoperative left ventricle ejection fraction (LVEF) < 45%) were revealed as prognostic factors. The receiver operator characteristics curve analysis for postoperative calculations of systemic immune-inflammatory index (SII) appeared significant (AUC = 0.698, p = 0.008), yielding sensitivity of 68.75% and specificity of 71.07%. Systemic immune-inflammatory index (SII) can be regarded as a predictive marker for long-term prognosis in diabetic patients after off-pump coronary artery bypass grafting. The role of perioperative inflammatory activation may play a crucial role in mortality prediction.

1 March 2001 in Heart
Verified
Journal Article
Closed access
PDF file
MJM Jemielity
M Jemielity
WDW Dyszkiewicz
W Dyszkiewicz
LPL Paluszkiewicz
L Paluszkiewicz
BPBartlomiej Perek
Bartlomiej Perek
PBP Buczkowski
P Buczkowski
APA Poniz˙yński
A Poniz˙yński
OBJECTIVE To determine the value of surgical closure of atrial septal defects in patients over 40 years of age. METHODS Retrospective analysis of 76 patients (63 women, 13 men), age range 40–62 years (mean (SD) 45.8 (5.1) years), who underwent surgical repair of atrial septal defect. Pre- and postoperative clinical status (New York Heart Association (NYHA) functional class) was assessed, and ECG,x ray, and echocardiographic investigations performed. Follow up was between 1 and 17 years. RESULTS One operative and one late death occurred during the study period. Before operation, 47 patients (61.8%) were in NYHA functional classes III and IV. After operation, 61 patients (82.4%) were in classes I and II. Four patients had atrial fibrillation before surgery versus nine after surgery. Before operation, 52 patients had intensified pulmonary vascularity compared with only seven after operation. Echocardiographic examination showed a significant reduction in right ventricular dimension (4.10 (0.91)v 2.95 (0.36) cm, p < 0.001). No residual intracardiac shunts were identified on echocardiographic follow up. CONCLUSIONS Surgical closure of atrial septal defects in patients over 40 years old can improve their clinical status and prevent right ventricular dilatation and insufficiency.