Paulina Dorota Felczak

Dr. Paulina Dorota Felczak

orcid

Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

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

Representative Publications

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6 January 2023 in Cells
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Journal Article
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Tomasz StępieńTomasz Stępień
Tomasz Stępień
STSylwia Tarka
Sylwia Tarka
NCNatalia Chmura
Natalia Chmura
MGMichał Grzegorczyk
Michał Grzegorczyk
AAAlbert Acewicz
Albert Acewicz
TWTeresa Wierzba-Bobrowicz
Teresa Wierzba-Bobrowicz
Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with the onset of neurological and psychiatric symptoms during and after the acute phase of illness. Inflammation and hypoxia induced by SARS-CoV-2 affect brain regions essential for fine motor function, learning, memory, and emotional responses. The mechanisms of these central nervous system symptoms remain largely unknown. While looking for the causes of neurological deficits, we conducted a study on how SARS-CoV-2 affects neurogenesis. In this study, we compared a control group with a group of patients diagnosed with COVID-19. Analysis of the expression of neurogenesis markers showed a decrease in the density of neuronal progenitor cells and newborn neurons in the SARS-CoV-2 group. Analysis of COVID-19 patients revealed increased microglial activation compared with the control group. The unfavorable effect of the inflammatory process in the brain associated with COVID-19 disease increases the concentration of cytokines that negatively affect adult human neurogenesis.

1 January 2012 in Folia Neuropathologica
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Journal Article
Open access
ELEliza Lewandowska
Eliza Lewandowska
Tomasz StępieńTomasz Stępień
Tomasz Stępień
TWTeresa Wierzba-Bobrowicz
Teresa Wierzba-Bobrowicz
PFPaulina Dorota Felczak
Paulina Dorota Felczak
GSGrażyna M. Szpak
Grażyna M. Szpak
EPElżbieta Pasennik
Elżbieta Pasennik
Maternal ethanol consumption during pregnancy may cause foetal alcohol syndrome (FAS). Our experiments of ethanol-treated female rats were based on the FAS model in humans; therefore, the results obtained may help explain the clinical mechanism of the disease development. The ultrastructural...

30 December 2024 in Journal of Clinical Medicine
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LKLarysa Krajewska-Węglewicz
Larysa Krajewska-Węglewicz
PFPaulina Dorota Felczak
Paulina Dorota Felczak
MDMałgorzata Dorobek
Małgorzata Dorobek
Background: Age-related changes to the orbicularis oculi muscle include impaired eyelid function, such as lagophthalmos, alterations in tear film dynamics, and aesthetic changes like wrinkles, festoons, and the descent of soft tissue. To date, the structural and functional changes that would comprehensively increase our understanding of orbicularis aging have not been analyzed. This study aims to investigate functional outcomes using surface electromyography and correlate them with ultrastructural changes in orbicularis during aging. Methods: This study enrolled 26 patients aged 37 to 78 years with a clinical diagnosis of dermatochalasis. Patients were divided into two age groups (<60 years; ≥60 years). Ultrastructural and electromyographical examinations were performed, and the electromyographical signals were correlated with the ultrastructural damage in the orbicularis. Results: This study revealed significantly lower values of average voluntary contraction and RMS of the surface electromyography signals in the older age group compared to the younger age group (p = 0.029 and p = 0.045, respectively). There was no statistically significant association between age and muscle damage (χ2(2) = 2.86, p > 0.05). There was no correlation between average voluntary contraction and the degree of ultrastructural damage in both groups (Spearman’s coefficient equaled 0.06923 and 0.64366, respectively). Conclusions: sEMG measurements are valuable for monitoring age-related functional changes in the orbicularis. Aging diminishes the functional capacity of the orbicularis, as evidenced by reduced contraction strength. This study, the first to compare ultrastructural and electromyographical changes in the orbicularis among dermatochalasis patients of different ages, finds that ultrastructural damage to muscle fibers is not directly responsible for the contraction strength decline.

1 January 2017 in Polish Journal of Pathology
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Journal Article
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PFPaulina Dorota Felczak
Paulina Dorota Felczak
ELEliza Lewandowska
Eliza Lewandowska
ISIwona Stępniak
Iwona Stępniak
MOMonika Oldak
Monika Oldak
APAgnieszka Pollak
Agnieszka Pollak
TWTeresa Wierzba-Bobrowicz
Teresa Wierzba-Bobrowicz
Ultrastructural changes in skeletal muscle biopsy in a 24-year-old female patient with clinically suspected mitochondrial encephalomyopathy lactic acidosis and stroke-like episodes (MELAS) syndrome are presented. We observed proliferation and/or pleomorphism of mitochondria in skeletal muscle and...

1 January 2014 in Folia Neuropathologica
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Journal Article
Closed access
ELEliza Lewandowska
Eliza Lewandowska
PFPaulina Dorota Felczak
Paulina Dorota Felczak
JBJulia Buczek
Julia Buczek
KGKarolina Gramza
Karolina Gramza
JRJanina Rafałowska
Janina Rafałowska
We report the case of an 84-year-old male patient afflicted by cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) showing minimal symptoms of disease. The patient was diagnosed on the basis of ultrastructural and genetic examinations....

21 December 2021 in Life
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Agnieszka ŁugowskaAgnieszka Ługowska
Agnieszka Ługowska
JPJoanna K. Purzycka-Olewiecka
Joanna K. Purzycka-Olewiecka
RPRafal Ploski
Rafal Ploski
GTGrazyna Teresa Truszkowska
Grazyna Teresa Truszkowska
MPMaciej Pronicki
Maciej Pronicki
MBMałgorzata Bednarska-Makaruk
Małgorzata Bednarska-Makaruk
We report on a 36-year-old man with cerebellar-extrapyramidal syndrome and severe heart failure because of dilated cardiomyopathy of unknown origin. Dysarthria and cardiac arrhythmia began at early childhood (4 years of age). Brain MRI (28 years of age) demonstrated severe cerebellar atrophy. At the age 32, he presented with dysarthria, ataxia, dystonia, and tremor of the right hand, bilateral slowed neural conduction in the visual pathways, and decreased mental acuity. At the age of 33 years, the patient underwent cardiac transplantation because of severe dilated cardiomyopathy. In the TPP1 gene, biallelic variants were identified: previously reported p.(Leu13Pro) and novel p.(Tyr508Cys) variant. Additionally, hemizygous novel missense variant in the ABCD1 gene was inherited from the mother p.(Arg17His). Normal very-long-chain fatty acids (VLCFA) levels both in patient and his mother excluded ABCD1 mutation as the pathogenic one. Tripeptidyl peptidase 1 (TPP1) activity was reduced (8,8 U/mg protein/h; reference range: 47.4 ± 10.7). In light microscopy the biopsy specimens obtained from explanted heart showed severe myocyte hypertrophy with perinuclear vacuolization with inclusions. Electron microscopy revealed absence of lipofuscin accumulation, no ultrastructural curvilinear profiles, fingerprint bodies, or granular osmiophilic deposits (GRODs) in lysosomes. As described here, the patient presents clinical symptoms observed in benign forms of ceroid lipofuscinosis type 2 (CLN2) and simultaneously some features of autosomal recessive spinocerebellar ataxia type 7 (SCAR7), which is also caused by mutations in the TPP1 gene.