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101.
102.
Pre-embedding light microscopic immunocytochemistry, using a monoclonal antibody (mAb-KA8) raised against a frog brain kappa receptor preparation, recognising selectively the kappa-opioid receptor, was used for studying the occurrence, distribution, and species-specificity of the kappa-opioid receptor in the hippocampal formation of four rodent species (rat, guinea pig, hamster and gerbil). MAb-KA8 immunoreactivity was detectable in the rat, hamster and gerbil hippocampus, however the distribution of the labelled structures was heterogeneous. In the rat and hamster the hilus of dentate gyrus and the stratum oriens of the CA1 area contained immunoreactive cell bodies and proximal dendrites. In the gerbil mAb-KA8 immunopositive cell bodies were recognisable in the stratum radiatum of the CA1 and CA3 areas and in the subiculum. In the hamster varicose axon-like elements were also detected in the CA3 pyramidal layer. With the mAb-KA8 antibody there was no detectable kappa opioid receptor labelling in the hippocampus of the guinea pig. The results confirm the high degree of species-specific heterogeneity characterising the distribution of opioid peptides and their receptors in the hippocampal formation. The receptor was found in most cases postsynaptically, however in the hamster the immunopositive axons may refer to a presynaptic localisation.  相似文献   
103.
The glycine transporter subtype 1 (GlyT1) is widely expressed in astroglial cells throughout the mammalian central nervous system and has been implicated in the regulation of N-methyl-D-aspartate (NMDA) receptor activity. Newborn mice deficient in GlyT1 are anatomically normal but show severe motor and respiratory deficits and die during the first postnatal day. In brainstem slices from GlyT1-deficient mice, in vitro respiratory activity is strikingly reduced but normalized by the glycine receptor (GlyR) antagonist strychnine. Conversely, glycine or the GlyT1 inhibitor sarcosine suppress respiratory activity in slices from wild-type mice. Thus, during early postnatal life, GlyT1 is essential for regulating glycine concentrations at inhibitory GlyRs, and GlyT1 deletion generates symptoms found in human glycine encephalopathy.  相似文献   
104.
The laboratory conditions for reproducible routine determination of staphylococcal cell-surface hydrophobicity by the salt aggregation test were standardized. Fresh bacterial suspensions standardized to 5 times 109 cfu/ml gave the most reproducible results with both Staphylococcus aureus and coagulase-negative staphylococci. For relatively hydrophobic strains a 5-min reading time was necessary to detect bacterial aggregation in ammonium sulphate solutions ranging from 0.1 M to 1.5 M, pH 6.8. A × 10 hand lens facilitated reading aggregations. Overnight storage of bacterial suspensions at 20C reduced cell-surface hydrophobicity of all species, while storage at 4C reduced the hydrophobic nature of Staph. aureus strains. The hydrophobicity of coagulase-negative staphylococci rarely changed at 4C. A 10-fold dilution of fresh, standardized bacterial suspensions made it impossible to detect bacterial aggregation in ammonium sulphate solutions even with a hand lens. Under standardized conditions three types of staphylococcal cell aggregations were observed. The first looked like the slide agglutination for O antigens of Enterobacteriaceae, the second resembled H-agglutination, while the third had a filamentous appearance. These patterns indicated that more than one component might contribute to cell-surface hydrophobicity of both Staph. aureus and coagulase-negative staphylococci, or the same component might have different position on the cell surface.  相似文献   
105.
Background aimsAdoptive transfer of tumor-infiltrating lymphocytes (TIL) has proven effective in metastatic melanoma and should therefore be explored in other types of cancer. The aim of this study was to examine the feasibility of potentially expanding clinically relevant quantities of tumor-specific T-cell cultures from TIL from patients with head and neck squamous cell carcinoma (HNSCC) using a more rapid expansion procedure compared with previous HNSCC studies.MethodsIn a two-step expansion process, initially TIL bulk cultures were established from primary and recurrent HNSCC tumors in high-dose interleukin (IL)-2. Secondly, selected bulk cultures were rapidly expanded using anti-CD3 antibody, feeder cells and high-dose IL-2. T-cell subsets were phenotypically characterized using flow cytometry. T-cell receptor (TCR) clonotype mapping was applied to examine clonotype dynamics during culture. Interferon (INF)-γ detection by Elispot and Cr51 release assay determined the specificity and functional capacity of selected TIL pre- and post-rapid expansion.ResultsTIL bulk cultures were expanded in 80% of the patients included, showing tumor specificity in 60% of the patients. Rapid expansions generated up to 3500-fold expansion of selected TIL cultures within 17 days. The cultures mainly consisted of T-effector memory cells, with varying distributions of CD8+ and CD4+ subtypes both among cultures and patients. TCR clonotype mapping demonstrated oligoclonal expanded cultures, ranging from approximately 10 to 30 T-cell clonotypes. TIL from large-scale rapid expansions maintained functional capacity, and contained tumor-specific T cells.ConclusionThe procedure is feasible for expansion of TIL from HNSCC, ensuring clinically relevant expansion folds within 7 weeks. The cell culture kinetics and phenotypes of the TIL resemble previously published results on TIL from melanoma, setting the stage for clinical testing of this promising treatment strategy for patients with HNSCC.  相似文献   
106.
The use cyclodextrins for the intensification of bioremediation by improving the mobility and bioavailability of contaminants has recently been studied. In this work, the role of randomly methylated -cyclodextrin in the bioremediation of soils contaminated with transformer oil was studied both in bench scale bioreactors and through field experiments. The aims of this research were to (a) establish the scientific background of a cyclodextrin-based soil bioremediation technology, (b) demonstrate its feasibility and effectiveness in the field, and (c) develop an integrated methodology, consisting of a combination of physical, chemical, biological and ecotoxicological analytical methods, for efficiently monitoring the technology performances. The stepwise increasing scale of the experiments and the application of the integrated analytical methodology supported the development of a scientifically established new technology and the identification of the advantages and the limitations of its application in the field. At each phase of the study, randomly methylated -cyclodextrin was found to significantly enhance the bioremediation and detoxification of the transformer oil-contaminated soils employed by increasing the bioavailability of the pollutants and the activity of indigenous microorganisms.  相似文献   
107.
To better manage invasive populations, it is vital to understand the environmental drivers underlying spatial variation in demographic performance of invasive individuals and populations. The invasive common ragweed, Ambrosia artemisiifolia, has severe adverse effects on agriculture and human health, due to its vast production of seeds and allergenic pollen. Here, we identify the scale and nature of environmental factors driving individual performance of A. artemisiifolia, and assess their relative importance. We studied 39 populations across the European continent, covering different climatic and habitat conditions. We found that plant size is the most important determinant in variation of per-capita seed and pollen production. Using plant volume as a measure of individual performance, we found that the local environment (i.e. the site) is far more influential for plant volume (explaining 25% of all spatial variation) than geographic position (regional level; 8%) or the neighbouring vegetation (at the plot level; 4%). An overall model including environmental factors at all scales performed better (27%), including the weather (bigger plants in warm and wet conditions), soil type (smaller plants on soils with more sand), and highlighting the negative effects of altitude, neighbouring vegetation and bare soil. Pollen and seed densities varied more than 200-fold between sites, with highest estimates in Croatia, Romania and Hungary. Pollen densities were highest on arable fields, while highest seed densities were found along infrastructure, both significantly higher than on ruderal sites. We discuss implications of these findings for the spatial scale of management interventions against A. artemisiifolia.  相似文献   
108.
Histamine is a biogenic amine with multiple physiological functions. Its importance in allergic inflammation is well characterized; moreover, it plays a role in the regulation of gastric acid production, various hypothalamic functions, such as food uptake, and enhancing TH2 balance during immune responses. Using histidine decarboxylase gene targeted (HDC(-/-)) BALB/c mice, we studied the effect of the absence of histamine on four cytochrome p450 enzyme activities. Their selective substrates were measured: ethoxyresorufin O-dealkylase activity of CYP1A, pentoxyresorufin O-dealkylase activity of CYP2B, chlorzoxazone 6-hydroxylase activity of CYP2E1 and ethylmorphine N-demethylase activity of CYP3A.The results indicate a significant elevation of CYP2E1 and CYP3A activities, however, no change in CYP1A and CYP2B activities was seen in HDC targeted mice compared to wild type controls with identical genetic backgrounds.  相似文献   
109.
Summary A tumor model system of clones of myeloproliferative sarcoma virus (MPV)-transformed rat fibroblasts (NRK) with different growth properties and metastatic potential was studied. The relationship between metastatic behavior and composition of carbohydrate-binding proteins (lectins) was analyzed by affinity chromatography. The metastatic variant differs qualitatively from its parental clone in the presence of galactoside-binding proteins at apparent molecular weights of 80 kDa, 70 kDa, 22 kDa, 18 kDa and 16 kDa and of a fucose-binding protein at apparent molecular weight of 42 kDa. The -glucosyl-binding proteins at apparent molecular weights of 67 kDa and 53 kDa and a galactoside-binding protein of apparent molecular weight of 34 kDa, however, are not detectable in the metastatic variant in comparison to its parental clone. In this respect the parental clone shows closer resemblance to the clone 5–8#1 with different growth properties and low metastatic potential than to its own metastatic variant. Furthermore, only the parental clone has a melibiose- and a mannan-binding protein of an apparent molecular weight of 64 kDa and 14 kDa, respectively. Rosette formation as model system for intercellular interaction reveals differences in the inhibition pattern with sugar between the two clones 5–8#1 and 5–20#20, whereas the metastatic variant 5–20#20 (s) exhibits drastically reduced capability to form rosettes. Initial experiments demonstrate the feasibility of drug targeting to transformed fibroblasts via carbohydrate-binding proteins.  相似文献   
110.
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