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1.
Variability in Brain Gangliosides of Fishes 总被引:1,自引:1,他引:0
2.
K P Zimmer J Caselitz G Seifert 《Virchows Archiv. B, Cell pathology including molecular pathology》1985,49(2):161-173
Epithelial cells from various sites and at various stages of differentiation reveal distinct cytokeratin polypeptide patterns. WE have localized these heterogeneous elements at the subcellular level in human salivary glands and in a solid tumor of the breast using a monoclonal and a polyclonal antibody against cytokeratin, and an antibody against tissue polypeptide antigen (TPA) which seems to be related to some cytokeratins. Labeling by the cytokeratin antibodies was more intense in squamous and duct cells than in acinar cells. The TPA:B1 antibody reacted predominantly with duct cells and to a lesser extent with acinar and squamous cells. A precise evaluation of the labeling pattern and a well-preserved cell structure appeared to be important factors in obtaining more detailed information about intermediate filament proteins. The cryoultramicrotomy and the protein A-gold technique are suitable for these studies. 相似文献
3.
A simple, sensitive and reliable assay for serotonin and 5-HIAA in brain tissue using liquid chromatography with electrochemical detection 总被引:11,自引:0,他引:11
An extremely sensitive and simple method for simultaneously measuring both serotonin and 5-hydroxyindoleacetic acid (5-HIAA) has been developed using liquid chromatography (LC) and electrochemical detection. Assay conditions are described which resolve and measure as little as 22 picograms of serotonin and its deaminated metabolite in deproteinated brain samples. 相似文献
4.
Ribonuclease III: new sense from nuisance. 总被引:6,自引:0,他引:6
Christian Conrad Reinhard Rauhut 《The international journal of biochemistry & cell biology》2002,34(2):116-129
RNases play an important role in the processing of precursor RNAs, creating the mature, functional RNAs. The ribonuclease III family currently is one of the most interesting families of endoribonucleases. Surprisingly, RNase III is involved in the maturation of almost every class of prokaryotic and eukaryotic RNA. We present an overview of the various substrates and their processing. RNase III contains one of the most prominent protein domains used in RNA-protein recognition, the double-stranded RNA binding domain (dsRBD). Progress in the understanding of this domain is summarized. Furthermore, RNase III only recently emerged as a key player in the new exciting biological field of RNA silencing, or RNA interference. The eukaryotic RNase III homologues which are likely involved in this process are compared with the other members of the RNase III family. 相似文献
5.
The cyclic pyrimidine nucleotide, cCMP, is an endogenous substance in mammalian cells but little is known on its functional role. We studied the effects of cCMP, its cell-permeant analogue, N4,2'-O-dibutyryl cytidine 3':5'-cyclic monophosphate (Bt2cCMP), and of butyrate on superoxide (O2-) formation and cytosolic Ca2+ [( Ca2+]i) in human neutrophils. Bt2cCMP inhibited O2- formation and the rise in [Ca2+]i induced by a chemotactic peptide at submaximally effective concentrations. O2- formation induced by platelet-activating factor was potentiated by Bt2cCMP, whereas the cyclic nucleotide had no effect on the rise in [Ca2+]i induced by this agonist. Bt2cCMP enhanced O2- formation induced by tau-hexachlorocyclohexane at a submaximally effective concentration. O2- formation stimulated by complement C5a, concanavalin A, NaF, A 23187, phorbol myristate acetate and arachidonic acid was not affected by Bt2cCMP. cCMP was less effective than Bt2cCMP to inhibit fMet-Leu-Phe-induced O2- formation, and butyrate was without effect on any of the functional parameters studied. Our data show that a cell-permeant analogue of cCMP differentially inhibits and potentiates activation of human neutrophils. 相似文献
6.
A retrospective study of disease and mortality in zebra finches 总被引:1,自引:0,他引:1
Few published reports exist describing morbidity and mortality in domestic zebra finch colonies maintained in a laboratory animal setting. A retrospective study of clinical disease and mortality in quarantined adult zebra finches was performed. Animals were observed during the 2 week quarantine period and for at least 1 month afterwards (42 days). Signs of disease, including feather and beak abnormalities, oculonasal discharge, increased respiratory rate or stridor, abdominal enlargement, pasty vent, diarrhea, lameness and pectoral muscle loss, were evaluated in our colony during this time. History, physical examination, laboratory testing and postmortem evaluation were used to determine causes of clinical disease. Common clinical findings in sick finches included sudden death, ruffled feathers, increased respiratory rate or gape mouthed breathing, pasty vent or frank diarrhea, and beak discoloration. Organisms frequently isolated were Staphylococcus spp., E. coli, Enterobacter spp., and Coccidia spp. Of the finches that died while in the colony (29.5%), 23.0% died in the first week after arrival. Pathogens frequently isolated from tissues cultured at necropsy included: E. coli, Staphylococcus aureus, Enterobacter spp., and Candida albicans. When observed, pathological lesions consisted of air sacculitis, fibrinopurulent polyserositis and ventriculitis. 相似文献
7.
Cardiac glycoside transport was investigated on the organ and whole plant level. Uptake experiments were carried out with shoot and root cultures of Digitalis lanata. In both systems primary cardenolides, i.e., those with a terminal glucose in their oligosaccharide side chain, were taken up against their concentration gradient, whereas the glucose-free secondary cardenolides were not. Active uptake of primary cardenolides was further evidenced by KCN inhibition of uptake. Using plantlets grown in vitro the long-distance transport of primary cardenolides from the leaves to the roots was demonstrated. Cardenolides were also detected in etiolated leaves, induced on plants with green leaves, which are supposed to be unable to synthezise cardenolides de novo, providing further evidence for long-distance transport. Several primary cardenolides were detected in the honeydew excreted by aphids fed on Digitalis lanata leaves, indicating that the phloem is a transporting tissue for cardenolides. On the other hand, the xylem sap obtained by applying the pressure-chamber technique was cardenolide-free. It was concluded that in Digitalis primary cardenolides serve as both the transport and the storage form of cardenolides. After their synthesis they are either stored in the vacuoles of the source tissue or loaded into the sieve tubes, from which they are unloaded at other sites where they are trapped in the vacuoles of the respective sink tissue. 相似文献
8.
Reinhard Told Stefan Palkovits Helmuth Haslacher Sophie Frantal Doreen Schmidl Agnes Boltz Michael Lasta Semira Kaya René M. Werkmeister Gerhard Garh?fer Leopold Schmetterer 《PloS one》2013,8(4)
A common polymorphism in the complement factor H gene (rs1061170, Y402H) is associated with a high risk of age-related macular degeneration (AMD). In the present study we hypothesized that healthy young subjects homozygous for the high-risk haplotype (CC) show abnormal choroidal blood flow (ChBF) regulation decades before potentially developing the disease. A total of 100 healthy young subjects were included in the present study, of which 4 subjects were excluded due to problems with genotyping or blood flow measurements. ChBF was measured continuously using laser Doppler flowmetry while the subjects performed isometric exercise (squatting) for 6 minutes. The increase in ChBF was less pronounced than the response in ocular perfusion pressure (OPP), indicating for some degree of choroidal blood flow regulation. Eighteen subjects were homozygous for C, 47 subjects were homozygous for T and 31 subjects were heterozygous (CT). The increase in OPP during isometric exercise was not different between groups. By contrast the increase in ChBF was more pronounced in subjects homozygous for the high risk C allele (p = 0.041). This was also evident from the pressure/flow relationship, where the increase in ChBF in homozygous C carriers started at lower OPPs as compared to the other groups. Our data indicate that the regulation of ChBF is abnormal in rs1061170 CC carriers. So far this polymorphism has been linked to age related macular degeneration (AMD) mainly via inflammatory pathways associated with the complement system dysfunction. Our results indicate that it could also be related to vascular factors that have been implicated in AMD pathogenesis. 相似文献
9.
10.
Bernd Höffken Reinhard Ködding Alexander von zur Mühlen Tainer Hehrmann Rolf-Dieter Hesch 《Biochimica et Biophysica Acta (BBA)/General Subjects》1978,539(1):114-124
The nature of the conversion of thyroxine (T4) to triiodothyronine (T3) and reverse triiodothyronine (rT3) was investigated in rat liver homogenate and microsomes. A 6-fold rise of T3 and 2.5-fold rise of rT3 levels determined by specific radioimmunoassays was observed over 6 h after the addition of T4. An enzymic process is suggested that converts T4 to T3 and rT3. For T3 the optimal pH is 6 and for rT3, 9.5. The converting activity for both T3 and rT3 is temperature dependent and can be suppressed by heat, H2O2, merthiolate and by 5-propyl-2-thiouracil. rT3 and to a lesser degree iodide, were able to inhibit the production of T3 in a dose related fashion. Therefore the pH dependendy, rT3 and iodide may regulate the availability of T3 or rT3 depending on the metabolic requirements of thyroid hormones. 相似文献