We investigated the dendritic patterns of rapid Golgi-impregnated, highly similar multipolar neurons from two functionally different thalamic regions of the rat brain: two dorsal nuclei (the nucleus laterodorsalis thalami, pars dorsomedialis and the nucleus laterodorsalis thalami, pars ventrolateralis), and two ventral nuclei (the nucleus ventrolateralis thalami and the nucleus ventromedialis thalami). The analysis involved conventional morphometric parameters (height and size) and a new parameter derived from graph theory, the relative imbalance (RI), derived from the branching patterns of the dendrites, which permits quantitative characterization of the dendritic arborization of a neuron. On this basis, neurons can be grouped into three fundamentally different types: type A, or highly-polarized (imbalanced) neurons (RI values close to 1); type B, or medium-polarized neurons (RI values around 0.5); and type C, or balanced neurons with low polarization (RI values close to 0). The orientations of the dendritic arbor, and thus the receptive fields, of the dorsal and ventral thalamic neurons, were mutually perpendicular. The H and S values indicated that the neurons in the dorsal and ventral thalamic nuclei differed significantly. However, their RI values demonstrated that they were similar neurons of type B. Our data reveal that 1) the dendritic arbor cannot be reliably characterized purely on the basis of height and size, and 2) RI is a valuable morphometric parameter that identifies the true nature of the dendritic arborization.
Authors:K. Régaiszné Vajda, A.A. Halbritter, P. Szűcs, J. Szigeti and B. Ásványi
Sous-vide (French for ʽunder vacuum’) is a professional cooking method, by which, under oxygen-free conditions and precise temperature control, not only cooking but preservation is achieved. During the process the food matrix is vacuum-packed and undergoes a mild heat treatment, thus achieving an enhanced nutrition value and a better organoleptic character. Due to the mild heat treatment (55 to 90 °C), the high water activity, and the slight acidity of raw materials, the microbial quality assurance is a great challenge even for professionals. The heat treatment does not assure the inactivation of pathogen spores. In our experiments we used Clostridium perfringens representing the spore-forming pathogens, and Salmonella Enteritidis as a the food-borne infection bacterium. Effects of various temperatures were measured in normal and sous-vide type vacuum packaging. Higher thermal death rate in vacuum packaging was demonstrated for Salmonella Enteritidis and Clostridium perfringens.
Authors:Gábor Skaliczki, M. Weszl, K. Schandl, T. Major, M. Kovács, J. Skaliczki, H. Redl, M. Szendrői, K. Szigeti, D. Máté, Cs Dobó-Nagy and Zs Lacza
Purpose: The clinical demand for bone grafting materials necessitated the development of animal models. Critical size defect model has been criticized recently, mainly for its inaccuracy. Our objective was to develop a dependable animal model that would provide compromised bone healing, and would allow the investigation of bone substitutes. Methods: In the first group a critical size defect was created in the femur of adult male Wistar rats, and a non-critical defect in the remaining animals (Groups II, III and IV). The defect was left empty in group II, while in groups III and IV a spacer was interposed into the gap. Osteoblast activity was evaluated by NanoSPECT/CT imaging system. New bone formation and assessment of a union or non-union was observed by μCT and histology. Results: The interposition model proved to be highly reproducible and provided a bone defect with compromised bone healing. Significant bone regeneration processes were observed four weeks after removal of the spacer. Conclusion: Our results have shown that when early bone healing is inhibited by the physical interposition of a spacer, the regeneration process is compromised for a further 4 weeks and results in a bone defect during the time-course of the study.