ABSTRACT
Our work was focused on physico-chemical and biological characteristics of Aries River, one of the largest rivers from Romania. Water samples were collected from 11 sites along Aries River course. We have measured de (18)O and D isotopic composition of Aries River water in these locations and correlated these data with the isotopic composition of aquatic plants and with the pollution degree. Some ions from Aries River water were also analyzed: NO(3)(-), NO(2)(-), PO(4)(3-) Cu(2+), Fe(3+). Analysis of diatom communities has been performed in order to quantify the level of water pollution of Aries River. All physico-chemical analyses revealed that the most polluted site is Abrud; the source of pollution is most probably the mining enterprise from Rosia Montana. Water isotope content increases from upstream to downstream of the locations analyzed. The structure of diatom communities is strongly influenced by the different pollution sources from this area: mine waters, industrial waters, waste products, land cleaning, tourism etc. The water eutrophication increases from upstream of Campeni to downstream of Campia Turzii.
Subject(s)
Rivers/chemistry , Water Pollutants, Chemical/analysis , Copper/analysis , Deuterium/analysis , Diatoms , Ecosystem , Iron/analysis , Nitrates/analysis , Nitrites/analysis , Oxygen Isotopes/analysis , Phosphates/analysis , Plants/chemistry , RomaniaABSTRACT
Examination of the expression pattern of the winged-helix transcription factor BF-1 outside of the neural tube in mouse embryos suggests that BF-1 is restricted to a population of cells that gives rise to the ectodermal placodes and their derivatives. Within the sensory cranial nerve ganglia, the expression of BF-1 distinguishes cells that arise from the placodes from those derived from the neural crest. Expression of a lacZ transgene targeted to the BF-1 locus was used to follow the placodal lineage during mouse development. Analysis of placodal development in mice with a targeted deletion of BF-1 reveals that, although BF-1 is required for proliferation of the cells arising from the nasal placode, it is not required for the proliferation, survival, or both, of placode-derived cells in the sensory cranial nerve ganglia. Dev Dyn 1999;215:332-343.
Subject(s)
Cell Lineage , Ectoderm/metabolism , Gene Expression Regulation, Developmental , Animals , Cell Movement , Chick Embryo , DNA-Binding Proteins/analysis , DNA-Binding Proteins/metabolism , DNA-Binding Proteins/physiology , Early Growth Response Protein 2 , Embryo, Mammalian/innervation , Embryo, Nonmammalian/innervation , Forkhead Transcription Factors , Ganglia, Sensory/anatomy & histology , Ganglia, Sensory/embryology , Ganglia, Sensory/metabolism , In Situ Hybridization , Mice , Mice, Inbred CBA , Mice, Transgenic , Nerve Tissue Proteins/analysis , Nerve Tissue Proteins/metabolism , Nerve Tissue Proteins/physiology , Time Factors , Transcription Factors/metabolismABSTRACT
A novel approach for the computation of optical flow based on an L (1) type minimization is presented. It is shown that the approach has inherent advantages since it does not smooth the flow-velocity across the edges and hence preserves edge information. A numerical approach based on computation of evolving curves is proposed for computing the optical flow field. Computations are carried out on a number of real image sequences in order to illustrate the theory as well as the numerical approach.
ABSTRACT
We generated mice with a null mutation of the forebrain-restricted transcription factor BF-1 to examine its function in brain development. Heterozygous animals have an apparently normal phenotype. Homozygous null BF-1 mutants die at birth and have a dramatic reduction in the size of the cerebral hemispheres. The development of the ventral telencephalon is more severely affected than that of the dorsal telencephalon. Telencephalic neuroepithelial cells are specified in the BF-1 mutant, but their proliferation is reduced. Dorsal telencephalic neuroepithelial cells also differentiate prematurely, leading to early depletion of the progenitor population. These results suggest that BF-1 controls the morphogenesis of the telencephalon by regulating the rate of neuroepithelial cell proliferation and the timing of neuronal differentiation.
Subject(s)
Brain/embryology , DNA-Binding Proteins/physiology , Nerve Tissue Proteins/physiology , Animals , Base Sequence , Brain/anatomy & histology , Cell Differentiation , Cell Division/physiology , Cerebral Cortex/cytology , Cerebral Cortex/embryology , DNA-Binding Proteins/genetics , Epithelial Cells , Epithelium/embryology , Forkhead Transcription Factors , Heterozygote , Homozygote , Mice , Mice, Mutant Strains , Molecular Sequence Data , Morphogenesis , Mutation , Nerve Tissue Proteins/genetics , Telencephalon/cytology , Telencephalon/embryologyABSTRACT
In order to elucidate the role of the inflammatory cytokines in regulating glucocorticosteroid binding (GCSB) and glucocorticosteroid receptor (GR) level we incubated a B-cell line (CESS), a promonocytic cell line (U937) and a hepatoma cell line (HepG2) in the presence of varying concentrations of IL-1 beta, IL-6 and TNF-alpha for 24 h. Glucocorticosteroid binding was determined by the method of 'whole cell uptake', and the cellular appearance of the glucocorticosteroid receptor was detected by immunocytochemistry. A rise in the glucocorticosteroid binding was induced by all three cytokines. The increase in level of glucocorticosteroid receptors in the cells shown by immunocytochemistry was much more pronounced. However, antagonistic effects were demonstrated by both methods between IL-6 and TNF-alpha, and between IL-1 beta and TNF-alpha when they were applied simultaneously, in U937. Present data suggest that local imbalance in the ratio of these three cytokines in different pathological cases might influence the glucocorticosteroid sensitivity of the lymphocytes, monocytes and hepatocytes as target cells.
