Comparison of chromosome centromere topology in differentiating cells with myogenic potential.

Chromosome territories (CT's) constitute the critical element of the intranuclear architecture. Position of these compartmentalized structures plays an important role in functioning of entire genome. Present study was to examine whether the centromeres position of chromosomes 4, X and Y can be changed during differentiation from myoblasts to myotubes. Topological analysis of these centromeres was based on two-dimensional fluorescent hybridization in situ (2D-FISH). During differentiation process the majority of X chromosome centromeres analyzed shifted to the peripheral part of a nucleus and similar phenomenon was observed with one of the chromosome 4 centromeres. Completely different tendency was noticed when investigating the location of the chromosome Y centromeres. Centromeres of this chromosome migrated to the centre of a nucleus. The results obtained demonstrated visible changes in chromosome topology along the myogenic stem cells differentiation

In vitro culture of primary human myoblasts by using the dextran microcarriers Cytodex3®

Introduction. Primary cells in vitro culture scale-up is a crucial issue in cell-based tissue and organ regeneration therapy. Reducing costs and space occupied by the cells cultured in vitro has been an important target. Cells cultured in vitro with the use of bioreactor with dextran microcarriers (Cytodex®) have potentially a chance to meet many of the cell therapy requirements. Material and methods. We used collagen-coated carriers (Cytodex3®) and a spinner flask bioreactor to develop environment suitable for human myoblast proliferation. In parallel, standard adherent in vitro culture conditions for myoblasts propagation (T-flask) were conducted. Cell cycle characterization, senescence, myogenic gene ex­pression and cell apoptosis were evaluated in order to find differences between two culture systems under study. Results. The number of cells obtained in bioreactor per 106 of starting cells population was approximately ten times lower in comparison with T-flask culture system. The microcarriers cultured adult myoblasts in compari­son with the regular T-flask culture showed faster and more advanced replicative aging and lower proliferative potential. Moreover, the percentage of the cells that entailed an irreversible cell arrest (G0 phase) was also significantly (p < 0.0001) increased. Conclusions. Our results suggest that population of primary human myoblasts obtained from adult individuals and propagated on dextran microcarriers did not meet the requirements of the regenerative medicine regarding quantity and quality of the cells obtained. Nonetheless, further optimization of the cell scaling up process including both microcarriers and/or bioreactor program is still an important option

Ecological compatibility of GM crops and biological control

Insect-resistant and herbicide-tolerant genetically modified (GM) crops pervade many modern cropping systems (especially field-cropping systems), and present challenges and opportunities for developing biologically based pest-management programs. Interactions between biological control agents (insect predators, parasitoids, and pathogens) and GM crops exceed simple toxicological relationships, a priority for assessing risk of GM crops to non-target species. To determine the compatibility of biological control and insect-resistant and herbicide-tolerant GM crop traits within integrated pest-management programs, this synthesis prioritizes understanding the bi-trophic and prey/host-mediated ecological pathways through which natural enemies interact within cropland communities, and how GM crops alter the agroecosystems in which natural enemies live. Insect-resistant crops can affect the quantity and quality of non-prey foods for natural enemies, as well as the availability and quality of both target and non-target pests that serve as prey/hosts. When they are used to locally eradicate weeds, herbicide-tolerant crops alter the agricultural landscape by reducing or changing the remaining vegetational diversity. This vegetational diversity is fundamental to biological control when it serves as a source of habitat and nutritional resources. Some inherent qualities of both biological control and GM crops provide opportunities to improve upon sustainable IPM systems. For example, biological control agents may delay the evolution of pest resistance to GM crops, and suppress outbreaks of secondary pests not targeted by GM plants, while herbicide-tolerant crops facilitate within-field management of vegetational diversity that can enhance the efficacy of biological control agents. By examining the ecological compatibility of biological control and GM crops, and employing them within an IPM framework, the sustainability and profitability of farming may be improved

The spectrum and occurrence of entomopathogenic fungi in soils from apple orchards

The spectrum and occurrence of entomopathogenic fungi in orchard soil and arable soil were evaluated using an „insect bait method”. Soil samples taken in autumn and spring from sward, herbicides fallow and arable soil were baited with Galleria mellonella larvae. Entomopathogenic fungi Beauveria bassiana (Bals.) Vuill., Metarhizium anisopliae (Metsch.) Sorok. and Paecilomyces fumosoroseus (Wize) Brown et Smith were isolated from three species of orchards soil and adjacent arable soil. Infection levels of G. mellonella larvae were depended from species of soil. M. anisoopliae caused most frequent infections of bait insects in light loamy sand and P. fumosoroseus in alluvial silt and coarse sand. B. bassiana was dominated in alluvial silt. It was established that M. anisopliae and B. bassiana infected more larvae in autumn than in spring. In case of P. fumosoroseus an opposite tendency was observed. Generály in arable soil and sward number of infected larvae was higher than other stands. In case of light loamy sand more infections of G. mellonella larvae were found in samples from herbicides fallow. Irrespective of soil type B. bassiana was the dominated species isolated from herbicides fallow, M. anisopliae from sward and P. fumosoroseus - from arable soil.Przy pomocy metody owadów pułapkowych badano skład gatunkowy i nasilenie występowania grzybów owadobójczych w 3 gatunkach gleb z sadów jabłoniowych, w ugorze herbicydowym, murawie i polu uprawnym przylegającym do danego sadu. Obserwacje śmiertelności larw prowadzono jesienią i wiosną. W ciągu 3 lat prowadzenia badań wykazano, że występowanie grzybów owadobójczych zależało od gatunku gleby; im była ona lżejsza, tym rejestrowano więcej infekcji larw G. mellonella. W pyle ilastym i piasku gliniastym mocnym dominował P. fumosoroseus, a w piasku słabo gliniastym - M. anisopliae. Jesień sprzyjała występowaniu B. bassiana w pyle ilastym oraz M. anisopliae w piasku gliniastym mocnym i piasku słabo gliniastym. Wiosną zaś, w pyle ilastym i piasku gliniastym mocnym częściej infekował larwy grzyb P. fumosoroseus, a w piasku słabo gliniastym M. anisopliae i P. fumosoroseus wywoływały zbliżone nasilenie mikoz. Ugór herbicydowy i murawa na piasku słabo gliniastym charakteryzowały się największą liczbą odławianych grzybów w porównaniu z glebą orną i pozostałymi gatunkami gleb. Niezależnie od gleby grzyb B. bassiana dominował w ugorze herbicydowym, M. anisopliae w murawie, a P. fumosoroseus w glebie ornej