11 research outputs found

    An immunohistochemical analysis of lymphocytic infiltrations in canine skin cancers

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    Lymphocytic infiltrations located in the extracellular matrix often accompany canine skin cancer. They can be characterised as an inflammatory infiltration and/or a second tumour – lymphoma. The aim of this study was an immunohistochemical analysis of a lymphocytic infiltration which accompanies spontaneous skin cancer. Twenty basal cell carcinoma, 20 non-keratinizing squamous cell carcinoma, 20 keratinizing squamous cell carcinoma and 8 sebaceous gland carcinoma samples which were accompanied by a lymphocytic infiltration and/or secondary lymphatic follicles were verified histopathologically. The expression of bcl-2, CD3, CD79α, Ki-67, MCM-3 and MCM-7 in the lymphocytic infiltration was evaluated. Four types of lymphocytic infiltrations were found: I – diffuse bcl-2⁺, II – diffuse bcl-2⁻, III – follicular bcl-2⁺/⁻ where the centre was bcl-2⁻, and the marginal zone of the follicles and the extrafollicular area were bcl-2⁺ and IV – aggregated bcl-2⁺, where the centre and periphery were bcl-2⁺. The I and IV type corresponds to lymphoma, II type is non-neoplastic immune response and III type suggest reactive follicular hyperplasia. The proliferation of lymphocytes which demonstrated the expression of neoplastic markers (I and IV), suggests preneoplastic phase (pseudolymphoma) or lymphoma – the second independent tumour. A high proliferative index of the follicular blc-2⁺/⁻ follicular infiltration indicates an increased immunological response of the host against skin cancer

    Morphology of immune organs after very virulent plus strain of Marek’s disease virus infection in vaccinated hens

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    Marek’s disease (MD) outbreaks in poultry flocks may be associated with overriding of vaccine immune protection by very virulent (vvMDV) or very virulent plus (vv+MDV) strains. This paper presents the study on lymphoid organ morphology in the latent phase of MD caused by vv+MDV which break post-vaccinal protection in hens. We also immunohistochemically examined B and T populations as well as B/T and CD4+/CD8+ ratio of lymphocytes in lymphatic organs and, as a background, in MD lymphomas from non-lymphatic organs. The number of antigen expressed cells was evaluated as a percentage of positive cells in the one power field. Organ samples were collected from 24 dead reproductive hens (Ross 308 line) in age between 35-56 weeks, infected with vv+MDV. The hens originated from farms with MD outbreaks, despite earlier routine vaccination with CVI988/Rispens + HVT. The control organ samples originated from 15 clinically healthy hens at the same age and line, subjected to the same vaccination schedule. The number of CD3+, CD8+ and TCRγδ+ cells was significantly lower in MDV infected thymus, spleen and cecal tonsils in comparison to that found in the control organs. The proportion of CD4+ was also distinctly reduced in the thymus and limited in the spleen of MDV infected hens. This study revealed that infection with field vv+MDV isolates might break post-vaccinal protection and influence the central and peripheral immune system. The decrease in CD8+ and TCRγδ+ cell number in the thymus, spleen and cecal tonsils suggests that primarily these cells are involved in cell-mediated cytotoxicity against MDV transformed cells during latency

    Numerical Analysis of Deformation and Flow in the Proximal Area of the Urethra

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    Pathological conditions of a male urethra, including fibrosis, have a mechanical background along the entire length of the urethra. They may be caused by excessive deformation of the urethra locally or globally. The condition of prolonged overload causes abnormal tissue remodelling and, consequently, the formation of a thick layer of scar tissue differentiated from the connective tissue of the urethra. This tissue, which has higher mechanical properties, is not highly deformable and therefore, causes a decrease in the diameter of the urethra, which results in conditions that disturb the natural flow of urine. In this paper, it was decided to determine the deformation conditions in the proximal part of the urethra. The study was conducted in three main stages. Transverse sections of the animal urethral tissues were prepared in order to examine mechanical properties and perform histological examinations. On the basis of these examinations, material models which fitted best for the experimental results were sought. Material constants of the Mooney-Rivlin material model with the best fit ratio were determined for further research. On the basis of histological photographs, a geometrical and numerical model of the urethra was developed. The urethra was tested in a flat state of deformation. The strain and stress fields of the Caucha tensor were examined. The methodology of testing the dynamics of the urine flow in the highly deformable urethra was proposed. This is important for the analysis of the influence of at excessive pressure on pathological tissue remodelling leading to fibrosis

    Spectral line-shapes investigation with Pound-Drever-Hall-locked frequency-stabilized cavity ring-down spectroscopy

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    A review of recent experiments involving a newly developed Pound-Drever-Hall-locked frequency-stabilized cavity ring-down spectroscopy (PDH-locked FS-CRDS) system is presented. By comparison to standard FS-CRDS, the PDH lock of the probe laser to the ring-down cavity optimized coupling into the cavity, thus increasing the ring-down signal acquisition rate nearly 300-fold to 14 kHz and reducing the noise-equivalent absorption coefficient by more than an order of magnitude to 7 × 10−11 cm−1. We discuss how averaging approximately 1000 spectra yielded a signal-to-noise ratio of 220000. We also discuss how the spectrum frequency axis was linked to an optical frequency comb, thus enabling absolute frequency measurements of molecular optical transitions at sub-MHz levels. Applications of the spectrometer to molecular line-shape studies are also presented. For these investigations, we use semi-classical line-shape models that consider the influence of Dicke narrowing as well as the speed dependence of the pressure broadening and shifting to fit spectra. We show that the improved precision and spectrum fidelity of the spectrometer enable precise determinations of line-shape parameters. We also discuss the importance of line-shape analysis with regard to the development of new spectroscopic databases as well as in the optical determination of the Boltzmann constant
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