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71.
Claudia Müller Hermann Herbst Barbara Uchanska-Ziegler Andreas Ziegler Friedrich Schunter Ingeborg Steiert Claude Muller Peter Wernet 《Human immunology》1985,14(4):333-349
The production and serologic, as well as immunochemical properties of a cytotoxic murine IgG monoclonal antibody (Tü109) that precipitates HLA-class I molecules, are described. In the microcytotoxicity assay Tü109 supernatant was demonstrated on a panel of 424 HLA-ABC, -DR, -DQ, -MT typed normal Caucasian blood donors to define an epitope on HLA-B locus molecules in great association with the supertypic specificity Bw4. Reactivity of supernatant showed MHC linked inheritance of the Tü109 determinant and discriminated the HLA-Bw4/Bw6 associated HLA-B locus split antigens. Weak or lack of binding on lymphocytes from some HLA-Bw4 heterozygous individuals, particularly typing for HLA-Bw44, appeared to be due to qualitative and/or quantitative variations of HLA-B locus molecules on the cell surface. With Tü109 ascites fluid, however, extra-reactivity on all HLA-Bw6+ cells was demonstrated. Preferential binding of supernatant to HLA-Bw4, but reactivity of ascites fluid with HLA-Bw6+ molecules in addition, was furthermore confirmed by IEF analysis of antigens immunoprecipitated with Tü109 from cell lysates. Thus the antibody may help to analyze the evolutionary relationship of the diallelic specificities Bw4 and Bw6. 相似文献
72.
L. Jakobsen D. Sandvang V. F. Jensen A. M. Seyfarth N. Frimodt-Møller A. M. Hammerum 《Clinical microbiology and infection》2007,13(8):830-832
In total, 120 Escherichia coli isolates positive for one of the gentamicin resistance (GEN(R)) genes aac(3)-II, aac(3)-IV or ant(2')-I were tested for gentamicin susceptibility by the agar dilution method. Isolates positive for aac(3)-IV or ant(2')-I had an MIC distribution of 8-64 mg/L, whereas isolates positive for aac(3)-II had MICs of 32 to >512 mg/L, suggesting a relationship between the distribution of MICs and the specific GEN(R) mechanism. The MIC distribution, regardless of the GEN(R) mechanism, was 8 - >512 mg/L, which supports the clinical breakpoint of MIC >4 mg/L suggested by EUCAST and questions the breakpoint recommended by the CLSI (> or =16 mg/L). 相似文献
73.
Rybnikova EA Pelto-Huikko M Rakitskaya VV Shalyapina VG 《Neuroscience and behavioral physiology》2003,33(4):399-404
In situ hybridization was used to study the distribution of corticoliberin receptors of subtypes 1 and 2 (CL-R1 and CL-R2 respectively) in different structures of the rat brain. Levels of CL-R1 mRNA in the brain were significantly greater than levels of CL-R2 mRNA, and the most intense expression of the CL-R1 gene was seen in forebrain structures, especially various neocortical, archicortical, and paleocortical regions in the cerebellar cortex. In addition, significant levels of CL-R1 mRNA expression were noted in the red nucleus and the reticular nucleus of the tegmentum. Intense expression of CL-R2 mRNA was observed in structures of the olfactory system, corticomedial parts of the amygdala, fields CA1–CA4 of the hippocampus, the ventromedial hypothalamus, and several brain stem nuclei. Moderate levels of CL-R2 mRNA were seen in the dorsolateral neostriatum. These results provide evidence that corticoliberin receptors of both subtypes are widespread in the brain. The different patterns of expression of CL-R1 and CL-R2 in the brain probably provide the basis for the functional specificity of action of corticoliberin in brain structures. 相似文献
74.
Alireza Rezania Carson H. Thomas Kevin E. Healy 《Annals of biomedical engineering》1997,25(1):190-203
Patterned surfaces with alternating regions of amino silanes [N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane (EDS)] and alkyl silanes [dimethyldichlorosilane (DMS)] have been used to alter
the kinetics of spatial distribution of cellsin vitro. In particular, we have previously observed the preferential spatial distribution of bone cells on the EDS regions of EDS/DMS
patterned surfaces (10). In this study, we examined whether the mechanism of spatial distribution of cells on the EDS regions
was adhesion mediated. Homogeneous layers of EDS and DMS were immobilized on quartz substrates and characterized by contact
angle, X-ray photoelectron spectroscopy, and spectroscopic ellipsometry. The strength of bone cell attachment to the modified
substrates was examined using a radial flow apparatus, within either 20 min or 2 hr of cell incubation in the presence of
serum. A Weibull distribution was chosen to characterize the strength of cell-substratum adhesion. Within 20 min of cell exposure,
the strength of adhesion was significantly larger on EDS and clean surfaces, compared with DMS surfaces (p<0.0001). Within 2 hr of cell incubation, there was no statistical difference between the strength of cell adhesion to EDS,
DMS, and clean surfaces. The results of this study suggest that the surface chemistry mediates adhesion-based spatial cell
arrangement through a layer of adsorbed serum proteins. 相似文献
75.
Many side-effects of red blood cell transfusion have been described. They include iron-overload, as well as allo- and autoantibody formation against red cells. During storage, erythrocytes undergo complex structural and biochemical changes. It has been suggested that accelerated and/or aberrant forms of the physiological erythrocyte aging process underlie the red cell storage lesion. This storage lesion may contribute to side-effects of transfusion as endothelial damage by release of internal erythrocyte constituents, (pro)inflammatory consequences, hampered microcirculation and oxygen delivery. Understanding the process that determines the fate of red blood cells after transfusion may contribute to the prevention of side-effects after red blood cell transfusion. This should be the focus of research on red blood cell transfusion in clinical transfusion medicine. 相似文献
76.
Studies on human T-cell lymphotropic virus types I (HTLV-I) and II (HTLV-II) are briefly reviewed from the viewpoint of molecular evolution, with special reference to the evolutionary rate and evolutionary relationships among these viruses. In particular, it appears that, in contrast to the low level of variability of HTLV-I among different isolates, individual isolates form quasispecies structures. Elucidating the mechanisms connecting these two phenomena will be one of the future problems in the study of the molecular evolution of HTLV-I and HTLV-II. 相似文献
77.
Sera from 1,943 individuals from Auckland, New Zealand, were tested for the presence of serum antibodies to human T cell lymphotropic virus I (HTLV I), mainly with an enzyme-linked immunosorbent assay (ELISA) with cell extracts as target antigen. The individuals tested were blood donors and mostly Caucasian, but included indigenous Maoris and representatives of several groups of Pacific islanders now resident in New Zealand. Also included were 37 patients with various hematological malignancies, including seven with T cell leukemias. Although 1% of samples were positive by ELISA, none of these were confirmed as positives by Western blotting. On the basis of these results we consider that it is unlikely that HTLV I infection occurs in Auckland; however, we cannot exclude the possibility that pockets of virus infection may occur in other parts of New Zealand or the South Pacific. 相似文献
78.
Twin studies provide estimates of genetic and environmental contributions to cognitive ability differences, but could be based
on biased samples. Here we report whole-population estimates using twins from unique mental surveys in Scotland. The Scottish
Mental Surveys of 1st June 1932 (SMS1932) and 4th June 1947 (SMS1947), respectively, administered the same validated verbal
reasoning test to almost everyone born in 1921 or 1936 and attending school in Scotland. There were 572 twin pairs from the
SMS1932, and 517 pairs from the SMS1947. Information on zygosity was unavailable. A novel application of a mixture distribution
was used to estimate genetic and environmental components of verbal reasoning variation by maximum likelihood. We found consistent
heritability (~0.70) and shared environment (~0.21) estimates. The estimates did not change substantially when additional
quantitative traits (height and weight) were added in a multivariate analysis. More generally for studies in genetics, the
methodological innovation developed here implies that large (national) data collections can provide sufficient information
on twin pairs to estimate genetic parameters, even without zygosity. 相似文献
79.
Eva Müller Wolfgang Neuhofer Akihiro Ohno Silvia Rucker Klaus Thurau Franz-X. Beck 《Pflügers Archiv : European journal of physiology》1996,431(4):608-617
The distribution of heat shock proteins (HSP) HSP60, HSP73, HSP72 and HSP25 in the isoosmotic cortex and the hyperosmotic medulla of the rat kidney was investigated using Western blot analysis and immunohistochemistry. HSP73 was homogeneously distributed throughout the whole kidney. The level of HSP60 was high in the renal cortex and low in the medulla. HSP25 and HSP72 were present in large amounts in the medulla. Only low levels of HSP25 and almost undetectable amounts of HSP72 were found in the cortex. HSP25 exists in one nonphosphorylated and several phosphorylated isoforms. Western blot analysis preceded by isoelectric focussing showed that HSP25 predominates in its nonphosphorylated form in the outer medulla but in its phosphorylated form in cortex and inner medulla. Although this intrarenal distribution pattern was not changed during prolonged anaesthesia (thiobutabarbital sodium), a shift from the nonphosphorylated to the phosphorylated isoforms of HSP25 occurred in the medulla. The characteristic intrarenal distribution of the constitutively expressed HSPs (HSP73, HSP60, HSP25) may reflect different states of metabolic activity in the isoosmotic (cortex) and hyperosmotic (medulla) zones of the kidney. The high content of inducible HSP72 in the medulla most likely is a consequence of the osmotic stress imposed upon the cells by the high urea and salt concentrations in the hyperosmotic medullary environment. 相似文献
80.
Mohammad Lutfur Rahman Masato Aoyama Shoei Sugita 《Anatomical science international / Japanese Association of Anatomists》2008,83(4):239-246
This study was intended to determine the number and density of both retinal ganglion cells and the oil droplets of cone photoreceptor
cells in brown-eared bulbul (Hysipetes amaurotis). For this study birds were killed with proper dose of anesthetic (pentobarbital, 30 mg/kg), and the eyes were removed from
the orbital cavity to isolate the retina. For the ganglion cell study retinal whole-mount specimens were prepared and stained
with 0.1% cresyl violet. The different types of oil droplets were counted from color microphotographs of freshly prepared
retinal samples. The mean total number of ganglion cells was estimated at approximately 2.5×106; with an average density of 16 523 cells/mm2. Two high-density areas, namely the central area (CA) and the dorso-temporal area (DTA), are located in the central and dorso-temporal
retinas, respectively, in bulbuls (24 032 cells/mm2 in the CA; 23 113 cells/mm2 in the DTA). Small ganglion cells persisted in the highest density areas, whereas the largest soma sizes were found in the
lowest density areas of the retina. Four types of different colored oil droplets — red, orange, green and clear — were identified
with an average density of 29 062/mm2. Among the different colors, the green oil droplets had a significantly higher population (13 083/mm2) than the others across the retina. The central retina had a significantly higher number of all types of oil droplets, at
a density of 60 552/mm2. The density and size of the different colored oil droplets were inversely related across the regions of the retina. Taken
together, it is concluded that the CA of the retina is an excellent quality area for visual perception due to peak density
of ganglion cells and oil droplets. Moreover, each specific oil droplet makes a distinct contribution to visual perception,
thereby ensuring that the bird has a retina that best matches its natural environment and feeding behavior. 相似文献