Marek Petráš

Prof. Marek Petráš

Third faculty of medicine, Charles University
orcid

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

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

Representative Publications

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11 July 2016 in Journal of Translational Medicine
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Journal Article
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ILIvana Kralova Lesna
Ivana Kralova Lesna
AKAnna Kralova
Anna Kralova
SKSona Kauerova
Sona Kauerova
JFJiri Fronek
Jiri Fronek
Marek PetrášMarek Petráš
Marek Petráš
RPRudolf Poledne
Rudolf Poledne
Macrophages play important roles in adipose tissue inflammation and its consequences. Unfortunately, a detailed description of the macrophage phenotypes in different human adipose tissues is not available. Subcutaneous, visceral and perivascular adipose tissues were obtained from 52 living kidney donors during live donor nephrectomy. Stromal vascular fractions were isolated, and the macrophage phenotypes were analyzed by flow cytometry using surface markers (CD14, CD16, CD36, and CD163). In addition to CD16 positivity, pro-inflammatory macrophages also display high scavenger receptor CD36 expression. The great majority of CD16 negative macrophages express the anti-inflammatory CD163 marker. The presence of pro-inflammatory macrophages was almost twice as high in visceral (p < 0.0001) and perivascular (p < 0.0001) adipose tissues than in subcutaneous tissue. This difference was substantially more pronounced in the postmenopausal women subgroup, consequentlly, the total difference was driven by this subgroup. We obtained detailed information about M1 and M2 macrophage phenotypes in human adipose tissue. The visceral and perivascular adipose tissues had substantially higher pro-inflammatory characteristics than the subcutaneous tissue. The higher proportion of pro-inflammatory macrophages in the visceral adipose tissue of postmenopausal women might be related to an increased cardiovascular risk.

22 December 2021 in Vaccines
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Marek PetrášMarek Petráš
Marek Petráš
ILIvana Králová Lesná
Ivana Králová Lesná
LVLivia Večeřová
Livia Večeřová
ENElka Nyčová
Elka Nyčová
JMJana Malinová
Jana Malinová
VAVěra Adámková
Věra Adámková
Continuous assessment of the effectiveness of approved COVID-19 vaccines is crucial to gain an insight into the longer-term impact on health outcomes, and eventually boosting public confidence. For this reason, we conducted a multicenter, retrospective cohort study using data on infection and vaccination rates among employees of three Prague hospitals in the period between 27 December 2020 and 31 August 2021. The post-vaccination and post-infection protectiveness were assessed in a total of 11,443 hospital workers who were followed up for more than 14 days either after their Comirnaty vaccination or study enrolment, depending on their previous SARS-CoV-2 infection. The effectiveness of full vaccination against any SARS-CoV-2 infection achieved 88.3% (83.2–91.8%) over the eight months of follow-up, a figure not much different from the 92.5% (76.5–97.6%) level of protection built by a previous infection. Despite this, the post-vaccination level of protection declined to about 65% between June and August. No case of breakthrough infection was registered among hospital workers having received one or two vaccine doses more than three months after previous infection. The eight-month effectiveness of the Comirnaty vaccine exhibited a declining trend requiring a new booster dose. The need for vaccination in the previously infected employees was not demonstrated conclusively in this study.

25 November 2022 in BMC Medicine
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Marek PetrášMarek Petráš
Marek Petráš
RMRoman Máčalík
Roman Máčalík
DJDaniela Janovská
Daniela Janovská
AČAlexander M. Čelko
Alexander M. Čelko
JDJana Dáňová
Jana Dáňová
ILIvana Králová Lesná
Ivana Králová Lesná
Background: Observational studies made it possible to assess the impact of risk factors on the long-term effectiveness of mRNA and adenoviral vector (AdV) vaccines against COVID-19. Methods: A computerized literature search was undertaken using the MEDLINE, EMBASE, and MedRxiv databases to identify eligible studies, with no language restrictions, published up to 28 February 2022. Eligible were observational studies assessing vaccine effectiveness (VE) by disease severity with reference groups of unvaccinated participants or participants immunized with one, two, or three vaccine doses. Our study was carried out in compliance with the PRISMA and MOOSE guidelines. The risk of study bias was identified using the Newcastle–Ottawa Quality Assessment Scale. The GRADE guidelines were applied to assess the strength of evidence for the primary outcome. The synthesis was conducted using a meta-analysis and meta-regression. Results: Out of a total of 14,155 publications, 290 studies were included. Early VE of full vaccination against COVID-19 of any symptomatology and severity decreased from 96% (95% CI, 95–96%) for mRNA and from 86% (95% CI, 83–89%) for AdV vaccines to 67% for both vaccine types in the last 2 months of 2021. A similar 1-year decline from 98 to 86% was found for severe COVID-19 after full immunization with mRNA, but not with AdV vaccines providing persistent 82–87% effectiveness. Variant-reduced VE was only associated with Omicron regardless of disease severity, vaccine type, or vaccination completeness. The level of protection was reduced in participants aged >65 years, with a comorbidity or those in long-term care or residential homes independently of the number of doses received. The booster effect of the third mRNA dose was unclear because incompletely restored effectiveness, regardless of disease severity, declined within a short-term interval of 4 months. Conclusions: Full vaccination provided an early high, yet waning level of protection against COVID-19 of any severity with a strong impact on the high-risk population. Moreover, the potential risk of new antigenically distinct variants should not be underestimated, and any future immunization strategy should include variant-updated vaccines.

8 August 2023 in Sexually Transmitted Infections
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Marek PetrášMarek Petráš
Marek Petráš
VDVladimír Dvořák
Vladimír Dvořák
DLDanuše Lomozová
Danuše Lomozová
RMRoman Máčalík
Roman Máčalík
SNSylva Neradová
Sylva Neradová
ILIvana Králová Lesná
Ivana Králová Lesná
Objective The main aim was to determine the overall vaccine effectiveness (VE) against recurrent cervical intraepithelial neoplasia grade 2 or worse (CIN2+) including specific VE associated with timing of human papillomavirus (HPV) vaccination using data from published studies. Design Meta-analysis and meta-regression. Data sources A computerised literature search was undertaken using the MEDLINE, EMBASE, International Pharmaceutical Abstracts, Derwent Drug File, ProQuest Science and Technology, Cochrane and MedRxiv databases. To be eligible, the studies, with no language restrictions, had to be published between 1 January 2001 and 25 May 2023. Review methods Included were studies with an unvaccinated reference group that assessed CIN2+ recurrence irrespective of the HPV genotype in women undergoing conisation provided. The present study was carried out in compliance with the Preferred Reporting Items for Systematic Review and Meta-Analyses and Meta-analysis Of Observational Studies in Epidemiology guidelines. The risk of study bias was assessed using the Newcastle–Ottawa Quality Assessment Scale. The Grading of Recommendations Assessment, Development, and Evaluation guidelines were used to assess the strength of evidence for the primary outcome. Data synthesis was conducted using meta-analysis and meta-regression. Results Out of a total of 14 322 publications, 20 studies with a total of 21 estimates were included. The overall VE against recurrent CIN2+ irrespective of the HPV genotype achieved 69.5% (95% CI: 54.7% to 79.5%). While the HPV vaccine valency, follow-up duration, type of study including its risk of bias had no effect on VE, the highest VE of 78.1% (95% CI: 68.7% to 84.7%) was reported for women receiving their first dose not earlier than the day of excision. This outcome was supported by additional analyses and a VE prediction interval ranging from 67.1% to 85.4%. Conclusions The outcome of this meta-analysis and meta-regression convincingly showed the beneficial effect of post-excisional HPV vaccination against CIN2+ recurrence. Studies published to date have been unable to determine whether or not vaccination, completed or initiated before conisation, would be associated with more favourable results. PROSPERO registration number CRD42022353530.

30 September 2008 in Respiratory Medicine
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Journal Article
Closed access
PPP. Panzner
P. Panzner
Marek PetrášMarek Petráš
Marek Petráš
TST. Sýkora
T. Sýkora
ILI. Lesná
I. Lesná

27 March 2020 in Vaccines
Verified
Journal Article
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Marek PetrášMarek Petráš
Marek Petráš
ILIvana Králová Lesná
Ivana Králová Lesná
JDJana Dáňová
Jana Dáňová
AČAlexander M. Čelko
Alexander M. Čelko
While the weight of epidemiological evidence does not support a causal link with influenza vaccination evaluated over the last 30 years, Guillain–Barré syndrome (GBS) has been considered a vaccine-associated adverse event of interest since 1976. To investigate the existence of GBS risk after vaccination against seasonal influenza, a systematic review and meta-analysis have been conducted based on 22 eligible epidemiological studies from 1981 to 2019 reporting 26 effect sizes (ESs) in different influenza seasons. The primary result of our meta-analysis pointed to no risk of vaccine-associated GBS, as documented by a pooled ES of 1.15 (95% CI: 0.97–1.35). Conversely, an obvious high risk of GBS was observed in patients with previous influenza-like illness (ILI), as demonstrated by a pooled ES of 9.6 (95% CI: 4.0–23.0) resulting from a supplementary analysis. While the meta-analysis did not confirm the putative risk of vaccine-associated GBS suggested by many epidemiological studies, vaccination against seasonal influenza reduced the risk of developing ILI-associated GBS by about 88%. However, to obtain strong evidence, more epidemiological studies are warranted to establish a possible coincidence between vaccination and ILI prior to GBS onset.