Michał Grzegorczyk

Dr. Michał Grzegorczyk

orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

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

Representative Publications

View All Publications
6 January 2023 in Cells
Verified
Journal Article
Open access
PDF file
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.

5 November 2021 in Animals
Verified
Journal Article
Open access
PDF file
OSOlga Szaluś-Jordanow
Olga Szaluś-Jordanow
MSMarta Stabińska-Smolarz
Marta Stabińska-Smolarz
Michał CzopowiczMichał Czopowicz
Michał Czopowicz
AMAgata Moroz
Agata Moroz
MMMarcin Mickiewicz
Marcin Mickiewicz
TFTadeusz Frymus
Tadeusz Frymus
Symptoms of infective endocarditis (IE) and myocarditis are usually nonspecific and include fever, apathy, and loss of appetite. This condition can lead to severe heart failure with ascites or/and fluid in the thoracic cavity or/and in the pericardial sac. We describe infective endocarditis and myocarditis in 3 dogs and 4 cats. In all animals, the initial diagnosis was performed on the basis of a focused cardiac ultrasound examination performed by a general practitioner after a training in this technique. The initial findings were confirmed by a board-certified specialist in veterinary cardiology. Post mortem positive microbiological results from valves were obtained in 4 of 7 patients. Methicillin-resistant Staphylococcus aureus was confirmed in 2 cases and Staphylococcus epidermidis was confirmed in 2 cases, one of which included Enterococcus sp. coinfection. Histopathological examination confirmed initial diagnosis in 5 of 7 animals. In the remaining 2 patients, the time elapsed from the onset of clinical symptoms to death was about 1 month and no active inflammation but massive fibrosis was found microscopically. This is, to our best knowledge, the first report of IE and myocarditis diagnosed in small animals using focused cardiac ultrasound examination. Therefore, we conclude that common usage of this technique by trained general veterinarians may increase the rate of diagnosed patients with these conditions.

28 October 2018 in Anatomical Science International
Verified
Journal Article
Open access
PDF file
MGMichał Grzegorczyk
Michał Grzegorczyk
Cristóbal Pablo KrasuckiCristóbal Pablo Krasucki
Cristóbal Pablo Krasucki
BCBogdan Ciszek
Bogdan Ciszek
The inner structure of the pons contains several layers of transverse and vertical fibers and many nuclei. The vertical bundles are described as fibers of the corticospinal tract, corticonuclear tract, frontopontine tract and parieto-temporopontine tract organized in three layers. The aim of this study was to investigate the structure of the vertical bundles in the ventral pons using the modified Klingler method. Ten brain stem specimens were investigated. Specimens were fixed in 10% formalin, frozen for 24 h to separate nerve fibers by ice crystals, and then unfrozen again in 10% formalin solution. Afterwards, the specimens were dissected using a sharpened spatula. Results point to the existence of three main layers of vertical bundles and a small, constant, and superficial fourth fascicle that is yet to be described in the literature. We propose the name fasciculus longitudinalis superficialis (superficial longitudinal fascicle) for this group of vertical fibers of the pons.

8 February 2025 in Animals
Verified
Journal Article
Open access
PDF file
AŁAndrzej Łobaczewski
Andrzej Łobaczewski
RSRafał Andrzej Sapierzyński
Rafał Andrzej Sapierzyński
SGSławomir Martin Gizinski
Sławomir Martin Gizinski
EKEwa Kautz-Wasilewska
Ewa Kautz-Wasilewska
AJAnna Jaśkiewicz
Anna Jaśkiewicz
TFTadeusz Frymus
Tadeusz Frymus
The reproductive cycle in domestic dogs involves prolonged phases of hormonal activity, making the endometrial tissue vulnerable to degenerative changes. One common result of these changes is cystic endometrial hyperplasia (CEH), which often leads to pyometra. Another, though rarer, condition is pseudo-placentational endometrial hyperplasia (PEH), characterized by abnormal proliferation of the endometrial glands and stroma, forming placental-like structures without the presence of pregnancy. Case presentation: An 8-year-old female Golden Retriever, healthy and intact, was presented for a routine ultrasound examination to confirm pregnancy after natural breeding 25 days earlier. Two previous pregnancies of this bitch have resulted in small but live litters. The ultrasound examination revealed multiple bilateral thickenings of the uterine horns, with ampullary-shaped enlargements measuring approximately 2.5 × 3.0 cm 25 days after breeding. The endometrium was conspicuously thickened, hypoechogenic, and either homogeneous or with scattered hyperechoic markings and faint striations. The mucosal surface ranged from regular to slightly irregular, and a small amount of hyperechoic condensed fluid was present in the lumen of the horns. No embryos were observed. Based on these findings, two primary diagnoses were considered: PEH or embryonic resorption sites, with a possible segmental uterine inflammation. A diagnosis suggestive of PEH was established through histopathological examination of the uterus after ovariohysterectomy, supported by consistent ultrasound findings that showed no progression or changes over time.