Nanomedycyna jako fundament medycyny personalizowanej

Recent years have witnessed unprecedented growth in research in the area of nanoscience. One of the most active applications of nanoscience, the ”science of the small particles usually less than 100 nm in diameter” is nanomedicine. Recent advances in biomedical research have generated opportunity to understand the factors underlying the development and progression of disease in individual patients. In addition, identifying factors which predict the individual response to treatment enable new approach to medicine through the stratification of treatment and prevention. This is the basis of personalised medicine. Several nanotechnology drugs and devices have already received regulatory approval; others are currently being investigated in clinical trials. This article addresses some points for utilisation of nanotechnology in personalised medicine. Kardiol Pol 2011; 69, 10: 1107–110

Transmission Electron Microscopy of Biological Samples

During the last 70 years, transmission electron microscopy (TEM) has developed our knowledge about ultrastructure of the cells and tissues. Another aim is the determination of molecular structure, interactions and processes including structure-function relationships at cellular level using a variety of TEM techniques with resolution in atomic to nanometre range. Even with the best transmission electron microscope, it is impossible to obtain real results without optimal sample preparation, respecting both the structure and the antigenicity preservation. Preparation techniques for high-resolution study of both macromolecular complex and organelles within cellular complex are based on fast cryoimmobilisation process, where the sample is in the most native, hydrated state. Next, thin samples are directly visualised under cryo-transmission electron microscopy (cryo-TEM), while thicker samples require a thinning step via cryo-electron microscopy of vitreous sections (CEMOVIS) or cryo-focused ion beam (cryo-FIB) before visualisation. Alternatively, vitrified samples are freeze substituted and embedded in chosen resin for room temperature ultramicrotomy. This preparation technique is suitable for morphological study, 3D analysis of cellular interior and immunoelectron microscopy. A different route for immunolocalisation study is cryosectioning according to the Tokuyasu technique that is a choice for rare or methacrylate-sensitive antigens. Most recently, new hybrid techniques have been developed for difficult-to-fix organisms and antigens or labile and anoxia-sensitive tissues. Another preparation technique is, the oldest but still important, conventional chemical fixation dedicated in a wide range of research interest, involving morphological and immunolocalisation study. In this chapter, we present different sample preparation approaches for transmission electron microscopy of biological samples, including its methodological basis and applications

Closer to the native state. Critical evaluation of cryo-techniques for Transmission Electron Microscopy: preparation of biological samples

Over the years Transmission Electron Microscopy (TEM) has evolved into a powerful technique for the structural analysis of cells and tissues at various levels of resolution. However, optimal sample preservation is required to achieve results consistent with reality. During the last few decades, conventional preparation methods have provided most of the knowledge about the ultrastructure of organelles, cells and tissues. Nevertheless, some artefacts can be introduced at all stagesofstandard electron microscopy preparation technique. Instead, rapid freezing techniques preserve biological specimens as close as possible to the native state. Our review focuses on different cryo-preparation approaches, starting from vitrification methods dependent on sample size. Afterwards, we discuss Cryo-Electron Microscopy Of VItreous Sections (CEMOVIS) and the main difficulties associated with this technique. Cryo-Focused Ion Beam (cryo-FIB) is described as a potential alternative for CEMOVIS. Another post-processing route for vitrified samples is freeze substitution and embedding in resin for structural analysis or immunolocalization analysis. Cryo-sectioning according to Tokuyasu is a technique dedicated to high efficiency immunogold labelling. Finally, we introduce hybrid techniques, which combine advantages of primary techniques originally dedicated to different approaches. Hybrid approaches permit to perform the study of difficult-to-fix samples and antigens or help optimize the sample preparation protocol for the integrated Laser and Electron Microscopy (iLEM) technique.(Folia Histochemica et Cytobiologica 2014, Vol. 52, No, 1, 1–17

Zapalenie mięśnia sercowego

Zapalenie mięśnia sercowego (MCI) jest jednostką chorobową o różnym przebiegu klinicznym, a także niepewnym rokowaniu. Jej głównymi przyczynami są infekcje wirusowe powodowane najczęściej adenowirusami i enterowirusami. Wśród pozostałych czynników etiologicznych MCI wymienia się: infekcje bakteryjne, grzybicze, pasożytnicze oraz czynniki fizyczne i chemiczne. Zapalenie mięśnia sercowego o charakterze przewlekłym występuje w przypadku schorzeń z autoimmunoagresji. Skutkiem MCI u części chorych jest rozwinięcie się pozapalnej kardiomiopatii rozstrzeniowej, przebiegającej zwykle z obrazem klinicznym przewlekłej skurczowej niewydolności serca. Podstawą rozpoznania MCI są głównie przebieg kliniczny oraz nieinwazyjne badania diagnostyczne. Wskazaniem do wykonania biopsji mięśnia sercowego jest piorunujący przebieg schorzenia oraz podejrzenie olbrzymiokomórkowego MCI. U większości chorych uzyskuje się dobrą odpowiedź na standardową terapię niewydolności serca. W razie braku skuteczności klasycznej i optymalnej farmakoterapii, a także potwierdzenia w badaniu biopsyjnym aktywnego MCI można rozważyć zastosowanie leczenia immunosupresyjnego. Część chorych może wymagać zastosowania sztucznego wspomagania krążenia i/lub oceny wskazań do transplantacji serca. Choroby Serca i Naczyń 2011, 8 (3), 124–13

Immunohistochemical assessment of mitochondrial superoxide dismutase (MnSOD) in colorectal premalignant and malignant lesions

Introduction: It is generally accepted that mitochondria are a primary source of intracellular reactive oxygen species (ROS). Under physiological circumstances they are permanently formed as by-products of aerobic metabolism in the mitochondria. To counter the harmful effect of ROS, cells possess an antioxidant defence system to detoxify ROS and avert them from accumulation at high concentrations. Mitochondria-located manganese superoxide dismutase (MnSOD, SOD2) successfully converts superoxide to the less reactive hydrogen peroxide (H2O2). To the best of our knowledge, there are no available data regarding immunohistochemical expression of MnSOD in colorectal neoplastic tissues. Aim: To investigate the immunohistochemical expression status of MnSOD in colorectal premalignant and malignant lesions. Material and methods: This study was performed on resected specimens obtained from 126 patients who had undergone surgical resection for primary sporadic colorectal cancer, and from 114 patients who had undergone colonoscopy at the Municipal Hospital in Jaworzno (Poland). Paraffin-embedded, 4-mu m-thick tissue sections were stained for rabbit polyclonal anti SOD2 antibody obtained from GeneTex (clone TF9-10-H10 from America Diagnostica). Results: Results of our study demonstrated that the development of colorectal cancer is connected with increased expression of MnSOD both in adenoma and adenocarcinoma stages. Samples of adenocarcinoma with G(2) and G(3) grade showed significantly higher levels of immunohistochemical expression of this antioxidant enzyme. Moreover, patients with the presence of lymphovascular invasion and higher degree of regional lymph node status have been also characterised by higher levels of MnSOD expression. The samples of adenoma have been characterised by higher levels of MnSOD expression in comparison to normal mucosa as well. Interestingly, there was no significant correlation between expression and histological type of adenoma. Conclusions: Development of colorectal cancer is connected with increased expression of MnSOD both in adenoma and adenocarcinoma stages. Keyword