Paulina Felczak

The diversity of mitochondria ultrastructure in human aging striated muscles is presented in relation to the complexity and variability of the cristae architecture and in relation to the environment of mitochondrial occurrence in the muscle fiber on the example of the orbicularis oculi. Ultrastructure analysis of mitochondria in muscles was performed using a transmission electron microscope. The studies revealed the presence of mitochondria of various sizes and unexpected shapes, and also modifications of the cristae architecture which included the occurrence of different configurations of membranes. In some mitochondria, instead of cristae, crystalline inclusion bodies and granules resembling calcium deposits were found. The range of diversity of the studied morphotypes of mitochondria exceeds the algorithms for the morphology of these organelles presented in the literature to date. This diversity of mitochondria should probably be viewed as a manifestation of evolution from the classical cristae architecture to a wide range of forms of mitochondria corresponding to the current environmental conditions of the muscle fiber.

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 (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.

Alzheimer's disease is a progressive neurodegenerative disorder that disrupts the brain regions involved in memory and cognitive functions. This impairment ultimately results in severe deficits in memory, learning, reasoning, communication, and the ability to perform daily activities. Our research reveals a statistically significant decrease in the density of neural progenitor cells within the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricles in patients diagnosed with Alzheimer's disease. This reduction correlates with the disease's progression. As Alzheimer’s disease advances, cognitive functions decline progressively, leading to the identification of five distinct stages of β-amyloid distribution across various brain structures. Early symptoms include short-term memory deficits and learning difficulties, along with cognitive, psychiatric, and neurological disturbances. Given the hippocampus's essential role in these functions, one would expect to see substantial changes in this brain region. Thus, understanding adult neurogenesis is vital in Alzheimer’s disease, particularly since the hippocampus, a primary neurogenic area, is notably impacted in affected individuals.

Neuronal ceroid lipofuscinoses (NCLs) are a growing group of neurodegenerative storage diseases, in which specific features are sought to facilitate the creation of a universal diagnostic algorithm in the future. In our ultrastructural studies, the group of NCLs was represented by the CLN2...

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.

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.

Herpes simplex encephalomyelitis (HSE) is a rare disease with a high mortality rate. Correct diagnosis is established on the basis of the combination of the clinical and investigative features. Unfortunately, precise diagnosis remains difficult due to several clinical similarities and false...

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...

Cel: Przedstawienie praktycznego zastosowania badania neuropatologicznego w praktyce medyczno-sądowej. Zwrócenie uwagi na przydatność rzadko to tej pory stosowanych badań neuropatologicznych szczególnie w przypadkach zgonów o niejasnej etiologii neurologicznej. Opis przypadku: 46-letnia kobieta uzależniona od alkoholu zmarła w przebiegu encefalopatii, klinicznie uznanej za encefalopatię toksyczną. Standardowa sekcja zwłok nie pozwoliła na jednoznaczne ustalenie przyczyny zgonu. Dzięki przeprowadzonemu badaniu neuropatologicznemu, które wykazało rozległą demielinizację i analizie przebiegu leczenia wykluczono toksyczną przyczynę zgonu i postawiono rozpoznanie zespołu demielinizacji osmotycznej w przebiegu zbyt szybkiej korekcji hiponatremii. Wnioski: Przypadek ten podkreśla istotną rolę neuropatologii w diagnostyce pośmiertnej i wskazuje na konieczność opracowania wytycznych i edukacji prokuratorów w kontekście jej stosowania w sekcjach sądowo-lekarskich.

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....