Juodžiukynienė, Nomeda

Background/Objectives: Cutaneous squamous cell carcinoma (cSCC) develops through inflammation-driven preneoplastic alterations characterized by epidermal hyperplasia, dysplasia, and increased proliferative activity. C-phycocyanin (C-PC) possesses antioxidant and anti-inflammatory properties; however, its topical potential to attenuate a tumour-promoting cutaneous microenvironment is limited by poor skin penetration. This study evaluated the effects of C-PC-loaded transfersomes in a 7,12-dimethylbenz[a]anthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse model of skin carcinogenesis. Methods: Male BALB/c mice were assigned to six groups (n = 10 per group). Carcinogenesis was initiated with a single topical application of DMBA, followed by twice-weekly TPA application for 16 weeks. C-PC-loaded transfersomes (1 mg/mL or 10 mg/mL) were applied topically. Histopathological assessment included epidermal thickness, rete ridge depth, mitotic activity, mast cell density, and semi-quantitative scoring of hyperplasia, dysplasia, and inflammation. Ki-67 immunohistochemistry was used to evaluate basal and suprabasal proliferation. Results: Carcinogen exposure induced marked epidermal thickening, severe dysplasia, increased mitotic activity, elevated Ki-67 expression, and pronounced dermal inflammation. Treatment with C-PC-loaded transfersomes significantly reduced epidermal thickness, rete ridge depth, mast cell density, mitotic counts, and suprabasal Ki-67 index. The 1 mg/mL concentration demonstrated the most consistent attenuation of dysplasia severity and inflammatory changes. No adverse histopathological alterations were observed in internal organs. Conclusions: These findings indicate that transfersome-mediated topical delivery of C-PC attenuates early inflammation-driven epidermal remodelling and tumour-promoting alterations in experimental skin carcinogenesis, supporting its potential as a topical preventive strategy.

Background: Early tumor-promoting events in skin carcinogenesis are characterized by increased keratinocyte proliferation, epidermal hyperplasia, and architectural alterations of the skin. Natural bioactive compounds with antiproliferative properties may represent promising chemopreventive strategies. C-phycocyanin (C-PC), a cyanobacteria - derived biliprotein, has demonstrated cytostatic and anti-inflammatory effects in experimental models (1-2). However, its topical delivery and influence on early tumor promotion require further investigation. Aim(s): To evaluate whether C-PC-loaded transfersomes modulate early proliferation- and dysplasiaassociated alterations in a mouse DMBA/TPA model of skin tumor promotion. Methods: Experimental skin carcinogenesis was induced using a classical DMBA/TPA initiation– promotion protocol. Animals were treated with C-PC-loaded transfersomes, empty transfersomes, or cancerogenic formulations. Histological assessment included epidermal thickness, rete ridge depth, and dysplasia grading. Immunohistochemical analysis of Ki-67 expression was performed separately in basal and suprabasal epidermal layers. Correlation analysis between suprabasal Ki-67 index and histopathological parameters was conducted. Statistical analysis included Welch’s ANOVA with Games–Howell post hoc test, Kruskal–Wallis analysis, and Spearman correlation (p < 0.05). Results: Tumor promotion induced marked epidermal hyperplasia, increased rete ridge formation, and elevated Ki-67 expression extending into suprabasal layers. Treatment with C-PC-loaded transfersomes significantly reduced epidermal thickness and suprabasal proliferative activity compared to untreated promoted skin. Suprabasal Ki-67 index positively correlated with epidermal thickness, rete ridge depth, and dysplasia grade, indicating its sensitivity as a marker of early pathological proliferation. Conclusion: Topical delivery of C-PC via transfersomes was associated with attenuation of early proliferative and structural alterations during skin tumor promotion in this experimental model. Further studies are required to clarify the underlying mechanisms and to determine their potential relevance in long-term chemopreventive strategies.

Background: Companion animals develop spontaneous tumors while sharing the same environmental carcinogenic exposures as humans. This positions dogs and cats as naturally occurring, immunocompetent models of cancer progression. However, tumors with identical histological labels can display distinctly different biological behaviors across species. Understanding these interspecies differences is essential both for veterinary clinical management and for harnessing dogs and cats as translational models relevant to human oncology. Methods: A retrospective analysis of 3525 histopathological cases (2861 dogs and 664 cats) diagnosed between 2020 and 2025 was conducted. Tumors were classified using ICD-O and Vet-ICD-O systems, and histological grading followed accepted veterinary adaptations of Elston–Ellis, Nagamine, and Kiupel criteria where applicable. Comparative evaluation focused on mammary gland carcinoma, squamous cell carcinoma (SCC), and lymphoma due to their high clinical relevance and cross-species translational significance. Results: Mammary gland carcinoma was prevalent in both species; however, feline tumors showed markedly higher malignancy rates (approximately 80–95%), early lymphovascular invasion, and predominance of solid and comedo patterns. In contrast, canine mammary tumors exhibited broader morphological heterogeneity and variable clinical courses. Squamous cell carcinoma was nearly three times more common in cats, typically affecting the oral cavity and nasal planum, and demonstrated aggressive local invasion comparable to human head and neck SCC. Lymphoma patterns diverged by species: canine lymphoma was predominantly multicentric with nodal enlargement, while feline lymphoma was primarily alimentary, often clinically resembling chronic enteropathy and requiring biopsy and immunophenotyping for accurate diagnosis. Conclusions: Although dogs and cats share environmental risks, the biological behavior of their tumors differs fundamentally. Feline mammary carcinoma should be approached as a systemic disease from the outset, oral SCC in cats provides a spontaneous model of locally aggressive human head and neck cancer, and feline alimentary lymphoma offers translational insight into immune-mediated gastrointestinal lymphomas. These distinctions reinforce the importance of species-specific diagnostic and therapeutic strategies and highlight the value of companion animals in comparative and translational oncology.

Šlapimo tyrimai veterinarijos praktikoje yra treti pagal tyrimų atlikimo dažnumą. Dažniau atliekami tik morfologinis ir biocheminis kraujo tyrimai. Šlapimo tyrimas svarbus siekiant nustatyti tikslią diagnozę, ypač esant šlapimo sistemos disfunkcijai, ir skirti tinkamą gydymą pacientui. Šlapimo tyrimo rezultatai reikalingi norint įvertinti gyvūno fizinę sveikatą, fiziologinę būklę, skysčių pusiausvyrą organizme, sergant sisteminėmis ligomis ar veikiant žalingiems aplinkos veiksniams. Šlapimo tyrimą rekomenduojama atlikti ir profilaktiškai, vykdant kasmetinį profilaktinį gyvūno ištyrimą, nes vertinant šlapimo tyrimų rezultatus galima įtarti inkstų funkcijos nepakankamumą dar nesant klinikinių požymių. Teisingai atliktas šlapimo tyrimas ir tinkamas rezultatų įvertinimas kartu su kitais tyrimų rezultatais (anamnezės, klinikinio tyrimo, kraujo tyrimų) padeda greičiau ir tiksliau diagnozuoti tokias ligas, kaip šlapimo organų sistemos ligos, ketozė, diabetas, kepenų disfunkcija, intravaskulinė hemolizė ir kt. Nors šlapimo tyrimas atrodo paprastas, bet, norint jį teisingai atlikti, kad būtų galima įvertinti rodmenis, reikia vadovautis tam tikra metodika. Netinkamai surinkus šlapimą, ne laiku pristačius jį į laboratoriją, neteisingai atlikus patį tyrimą, rezultatų vertinimas bus klaidingas. O neteisingai įvertinus rezultatus, nebus galima tiksliai diagnozuoti ligos, todėl kyla rizika, kad gyvūnas nepasveiks. Taigi, šioje mokomojoje knygoje pateikta naujausiais mokslinių tyrimų duomenimis paremta informacija padės studentams ir veterinarijos gydytojams lengviau ir tiksliau įvertinti šlapimo tyrimų rezultatus diagnozuojant ligas ir gydant pacientus.

Signal transducer and activator of transcription (STAT) proteins play a crucial role in cellular processes such as proliferation, differentiation, apoptosis, and immune response regulation [1]. Aberrant STAT signalling has been extensively studied in human cancers, yet its role in veterinary oncology, particularly in canine soft tissue tumours (STTs), remains underexplored. This study aimed to investigate the expression profiles of key STAT genes (STAT1, STAT3, and STAT5) in a cohort of canine STTs and assess their potential association with tumour grade, histological subtype, and clinical outcome. Tumour samples were collected from client-owned dogs diagnosed with STTs at veterinary clinics. Gene expression was analysed using quantitative real-time PCR (qRT-PCR), and protein localisation was assessed via immunohistochemistry. Preliminary results indicate differential expression patterns of STAT genes across tumour subtypes. Notably, STAT3 was significantly upregulated in high-grade tumours compared with low-grade ones (P < 0.05), suggesting a role in tumour aggressiveness. STAT1 expression showed variability, potentially reflecting its dual role in tumour suppression and immune modulation. STAT5 expression was relatively consistent but appeared elevated in certain sarcoma variants [1, 2]. Our findings support the hypothesis that dysregulated STAT signalling contributes to the pathogenesis of canine STTs. STAT3, in particular, may serve as a prognostic marker or therapeutic target in aggressive tumours. Further investigation is warranted to explore STAT-mediated pathways and their potential for targeted therapy in canine oncology. This study provides a foundation for integrating molecular markers into the diagnostic and prognostic evaluation of canine soft tissue tumours, bridging the gap between veterinary and comparative oncology.

The objective of this study was to assess the prevalence and clinicopathological characteristics of tumors in dogs and cats in Lithuania. A total of 3525 routine diagnostic samples collected from 1 January 2020 to 1 July 2025 were microscopically examined and statistically analyzed. Tumor prevalence was slightly higher in dogs (59.2%, n = 1693) compared with cats (56.5%, n = 375). Mammary gland tumors, skin tumors, and sarcomas were the most common neoplasms in both species, although notable interspecies differences were identified. In particular, feline mammary carcinomas were more aggressive, and squamous cell carcinoma was significantly more frequent in cats. These findings are consistent with international epidemiological trends and highlight the importance of species-specific diagnostic and management strategies.

Paukštiena intensyviausiai produkuojama mėsa. Atranka, siekiant išveisti viščiuką broilerį, prasidėjo penktajame praėjusio amžiaus dešimtmetyje norint paspartinti raumenų vystymąsi. Pakitusi fiziologija paveikė broilerių raumeninį audinį. Vystosi skeleto-raumenų patologijos, miopatijos. Disertacijoje analizuojamos Ross 308 viščiukų broilerių miopatijos. Disertacijos tikslas - ištirti viščiukų broilerių miopatijų pasireiškimą pulkuose, išanalizuoti pagrindinius etiologinius veiksnius ir patomorfologinius pokyčius bei įvertinti miopatijų įtaką greitai augančių broilerių sveikatingumui ir paukštienos kokybei. Tyrimas atliktas etapais. Skerdyklose atliktas makroskopinis miopatijų vertinimas, tirtas paplitimo mastas Lietuvoje, galimos miopatijų priežastys, miopatijos analizuotos vertinant raumenų histologinius pokyčius. Atlikta kraujo biocheminė analizė. Tirtos paukštienos fizikinės ir cheminės savybės. Disertacijoje pirmą kartą aprašyti rezultatai, gauti ištyrus lakiuosius organinius junginius ir biogeninius aminus raumenyse su didžiojo krūtinės raumens miopatijomis. Atliekant histomorfometrinę analizę, miopatijų paveiktuose raumenyse pirmą kartą apskaičiuota ne tik skaidulinio jungiamojo ir raumeninio, bet ir riebalinio audinio procentinė išraiška. Remiantis makroskopinės ir mikroskopinės analizės rezultatais, turėtų būti sukurta tinkama miopatijų klasifikavimo sistema, kuri prisidėtų prie ekonominių nuostolių mažinimo, užtikrintų patogų ir lengvai skerdyklose pritaikomą mėsos rūšiavimą.

Abstract. The study at Akhmet Baitursynov Kostanay Regional University examined the agerelated changes in glandular epithelium in cows' uterine horns. Results showed maximum activity in cows' first calving, followed by a decrease in subsequent calvings and a peak in the fourth and fifth calvings. Optimal indicators were observed during the fourth to sixth calving period. Introduction: The endometrium is a crucial component of the reproductive system in cows, creating the conditions necessary for embryo implantation, placenta formation, and a successful pregnancy. As cows age, metabolic processes undergo transformations: vascularization decreases, the density of glandular structures diminishes, and dystrophic and fibrotic changes occur [1,3]. These factors can impair a cow's reproductive capacity, lowering the likelihood of conception and increasing the risk of embryonic mortality [2,4]. The limited publications on this topic highlight the ongoing need for further research in this area. Purpose of the study: to investigate the functional characteristics of the glandular epithelium of the uterine horns from an age-related perspective based on cytometric analyses. Materials and Methods: Research material: uterine horn tissues from cows obtained at a slaughterhouse. The animals were divided into six age groups: Group 1 (1 calving), Group 2 (2-3 calvings), Group 3 (4-5 calvings), Group 4 (6 calvings), Group 5 (7 calvings), and Group 6 (8 calvings and older). Histological preparations were made using a classical method, with paraffin sections stained with hematoxylin-eosin [5]. Diameters of glands and exocrinocytes were measured. Histopreparations were examined and photographed, and statistical data processed using Excel 2019. Results: The functional activity of uterine body exocrinocytes in cows is highest after their first calving, then declines to the minimum value after second and third calvings. A significant increase is observed by the fourth and fifth calvings, followed by a gradual decrease after the sixth calving. The nuclear-plasma ratio of the uterine body covering layer reaches its maximum in cows during their first calving. The maximum sizes of glands in the right horn correspond to those in the left horn, but only in terms of internal diameter and height. The functional activity of exocrinocytes in the left uterine horn is most pronounced in young animals (2-5 calvings), but at six calvings, their activity is restored. In contrast, the functional activity of exocrinocytes in the right uterine horn reveals a different pattern, with minimal activity in cows with 2-3 calvings and a significant increase in the right horn by the 6th calving.

A change in testicular volume can indicate decreased male fertility and is useful for comparing spermatogenesis before and after experiments in animals, or before and after treatment of especially valuable domestic breeding animals with pharmaceuticals affecting spermatogenesis, such as antitumor drugs. Various formulae can be used to calculate the volume of living males’ testes. This study examined the suitability of four testicular volume calculation formulas for male Wistar rats of different ages (2-months, 1-year, and 2-years-old) and the changes in testicular volume during 90 days of observation. In 2-months-old rats, the solid ellipsoid triaxial body calculation formula and the prolate ellipsoid formula were most suitable for the calculation of testes’ volume, and the volume of both testes increased very significantly during the 90 days of observation. In 1-year-old rats, the solid ellipsoid triaxial body calculation formula was optimal, and the volume of both testes increased insignificantly. For 2-years-old rats, the solid ellipsoid triaxial body calculation and prolate ellipsoid formulas or their average was recommended, and the volume of both testes decreased slightly during 90 days of observation.

The purpose of the present study was to evaluate mast cell density in squamous cell carcinoma tissues of dogs and cats to assess species differences. Skin squamous cell carcinoma tissues from dogs (n = 15: n = 10 from body sites and n = 5 nail bed specimens) and cats (n = 15, n = 10 from ears and n = 5 nasal planum specimens) were examined. Intratumoral mast cell density (IMCD), peritumoral mast cell density (PMCD) and total mast cells density (TMCD) as a sum of IMCD and PMCD were calculated from Giemsa-stained slides at high magnification in 1 mm2 using an Olympus microscope (Olympus BX41, Tokyo, Japan) equipped with a digital Olympus DP72 image camera and CellSensDimension software V1.16). Both intratumoral and peritumoral tissues of the squa.mous cell carcinoma were divided into two categories: (1) loose, well-vascularized, rich in lymphocytes and plasmocytes, macrophages and neutrophils; and (2) fibrous, with few or no lymphocytes, plasmocytes, macrophages and neutrophils (the presence of neutrophils can be associated with actinic keratosis, mechanical irritation of the tumor in some anatomical areas during scratching with teeth, but, in general, neutrophils are associated with more invasive squamous cell carcinoma). In cats, a markedly higher total number of mast cells was found, and the number was also higher in intratumoral and peritumoral tissues. A similar tendency was found in both dogs and cats—a markedly higher number of mastocytes was found in both peritumoral and intratumoral loose, well-vascularized connective tissue. Conversely, lower numbers of mast cells were found in both intratumoral and peritumoral compact fibrous tissue in both animal species.