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21.
Summary Intra-ocular deposition of horseradish peroxidase was used to visualize optic tract projections in normal and congenitally monophthalmic catfish and Xenopus. In neither species was evidence for an increased ipsilateral visual component found in congenitally one-eyed specimens. This indicates that competition between axons from both eyes is not an important mechanism for fiber distribution in the chiasm during ontogeny. Furthermore, it suggests that enhanced ipsilateral components, previously noted in unilaterally enucleated fish and anurans, are caused by debris of degenerated axons. 相似文献
22.
A. J. J. Dietrich 《Genetica》1986,71(3):161-165
The copy number of the mdg-1 mobile element was determined by biotinylated-DNA hybridization, in salivary gland chromosomes of inbred Drosophila melanogaster larvae from sib progenies. It appears that the lower the egg-to-adult survival (viability), the higher the mdg-1 copy number in the surviving larvae. This suggests a common regulation of the mdg-1 copy number and the viability under inbreeding. 相似文献
23.
Wolfgang Hagmann Claudio Denzlinger Stephan Rapp Gisbert Weckbecker Dietrich Keppler 《Prostaglandins & other lipid mediators》1986,31(2)
Mercapturic acid formation, an established pathway in the detoxication of xenobiotics, is demonstrated for cysteinyl leukotrienes generated in rats
after endotoxin treatment. The mercapturate N-acetyl-leukotriene E4 (N-acetyl-LTE4) represented a major metabolite eliminated into bile after injection of [3H]LTC4 as shown by cochromatography with synthetic N-acetyl-LTE4 in four different HPLC solvent systems. The identity of endogenoud N-acetyl-LTE4 elicited by endotoxin
was additionally verified by enzymatic deacetylation followed by chemical N-acetylation. The deacetylation was catalyzed by penicillin amidase. Endogenous cysteinyl leukotrienes were quantified by radioimmunoassay after HPLC separation. A N-acetyl-LTE4 concentration of 80 nmol/l was determined in bile collected between 30 and 60 min after endotoxin injection. Under this condition, other cysteinyl leukotrienes detected in bile by radioimmunoassay amounted to less than 5% of N-acetyl-LTE4. The mercapturic acid pathway, leading from the glutathione conjugate LTC4 to N-acetyl-LTE4, thus plays an important role in the deactivation and elimination of these potent endogenous mediators. 相似文献
24.
Haemostatic alterations in malaria correlate to parasitaemia 总被引:2,自引:0,他引:2
Fibrin(ogen) degradation products, platelet counts, antithrombin III, and the components of the Factor VIII complex were studied in a total of 80 patients with Plasmodium falciparum, Plasmodium vivax or Plasmodium ovale infections. The haemostatic findings were correlated to the numbers of parasitized erythrocytes and to each other. The results indicate that haemostatic changes in malaria correlate with the degree of parasitaemia. Evidence for moderate hyperfibrinolysis was found in patients with high P. falciparum parasitaemias only. Thrombocytopenia closely corresponded to parasitaemia and to von Willebrand factor levels, but appeared not to be linked to a consumption of coagulation factors. It was concluded that thrombocytopenia in malaria is not indicative of disseminated intravascular coagulation (DIC) but may relate to endothelial damage. 相似文献
25.
Preliminary clinical observations with recombinant interleukin-2 in patients with AIDS or LAS 总被引:2,自引:0,他引:2
The toxicity of recombinant Interleukin-2 (IL-2) was studied in patients with acquired immunodeficiency syndrome (AIDS) or persistent lymphadenopathy syndrome (LAS). Increasing doses of the drug from 10(3) Units/m2 to 10(6) U/m2 were given as an intravenous bolus injection. At the high-dose levels some minor effects, such as fever up to 39.5 degrees C, chills, malaise or vomiting, were observed. The administration of 10(6) U/m2 as a 4-hour infusion showed identical results. No particular alterations of laboratory parameters were found. At the high-dose level the serum concentration of neopterin, which is released from macrophages after interferon gamma stimulation, was significantly (p less than 0.001) elevated above pretreatment levels. The clinical observation of daily infusions of 10(6)/m2 for 14 days revealed the same side effects. All patients developed lymphocytosis and eosinophilia. Two patients had suffered from severe diarrhoea for several weeks presumably due to cryptosporidiosis. In both cases diarrhoea ceased under the treatment with IL-2 and did not occur in the following two months. 相似文献
26.
C P Dietrich J F de Paiva C T Moraes H K Takahashi M A Porcionatto H B Nader 《Biochimica et biophysica acta》1985,843(1-2):1-7
The isolation, some structural features, physicochemical properties and pharmacological activities of a heparin from Anomalocardia brasiliana are reported. It is shown that the mollusc heparin is very similar to those present in mammalian tissues with regard to chemical composition, physicochemical properties, pharmacological activities and susceptibility to heparinase and heparitinase II from Flavobacterium heparinum, as well as to the types of products formed by the action of these enzymes. Three significant quantitative differences were observed for the mollusc heparin when compared with the ones from mammalian origin, namely, a higher degree of binding with antithrombin III (45%), higher molecular weight (27-43 kDa) and higher anticoagulant activity (320 I.U./mg). The possible biological role of heparin is discussed in view of the present findings. 相似文献
27.
Complete complementary DNA of rat tyrosine aminotransferase messenger RNA. Deduction of the primary structure of the enzyme 总被引:11,自引:0,他引:11
T Grange C Guénet J B Dietrich S Chasserot M Fromont N Befort J Jami G Beck R Pictet 《Journal of molecular biology》1985,184(2):347-350
The primary structure of rat tyrosine aminotransferase (L-tyrosine:2-oxoglutarate aminotransferase; EC 2.6.1.5), a liver-specific enzyme involved in gluconeogenesis, has been deduced from the nucleotide sequence of a cloned full-length cDNA. The mRNA is 2362 nucleotides long (excluding the poly(A) tail) and codes for a polypeptide of 454 amino acids with a molecular weight of 50634. Unambiguous identification was obtained by comparison of this sequence with the amino acid sequences of several peptides obtained from the purified enzyme. 相似文献
28.
The kinetic equation for the chloride transport cycle of band 3. A 35Cl and 37Cl NMR study 总被引:3,自引:0,他引:3
The nature of a transmembrane transport process depends largely on the identity of the reaction that is rate-limiting in the transport cycle. The one-for-one exchange of two chloride ions across the red cell membrane by band 3 can be decomposed into two component reactions: 1) the binding and dissociation of chloride at the transport site, and 2) the translocation of bound chloride across the membrane. The present work utilizes 35 Cl NMR and 37 Cl NMR to set lower limits on the rates of chloride binding and dissociation at the saturated inward- and outward-facing band 3 transport sites (greater than or equal to 10(5) events site-1 s-1 in all cases). At both 0-3 and 37 degrees C, the NMR data specify that chloride binding and dissociation at the saturated transport sites are not rate-limiting, indicating that translocation of bound chloride across the membrane is the slowest step in the overall transport cycle. Using these results, it is now possible to describe many features of the kinetic equation for the ping-pong transport cycle of band 3. This transport cycle can be decomposed into two half-reactions associated with the transport of two chloride ions in opposite directions across the membrane, where each half-reaction is composed of sequential binding, translocation, and dissociation events. One half-reaction contains the rate-limiting translocation event that controls the turnover of the transport cycle; in this half-reaction, translocation must be slower than binding and dissociation. The other half-reaction contains the non-rate-limiting translocation event that in principle could be faster than binding or dissociation. However, when the following sufficient (but not necessary) condition is satisfied, both translocation events are slower than binding and dissociation: if the non-rate-limiting translocation rate is within a factor of 10(2) (0-3 degrees C) or 2 (37 degrees C) of the overall turnover rate, then translocation is rate-limiting in each saturated half-reaction. Thus, even though chloride appears to migrate through a channel that leads from the transport site to solution, the results support a picture in which the binding, dissociation, and channel migration events are rapid compared to the translocation of bound chloride across the membrane. In this case, chloride binding to the transport site can be described by a simple dissociation constant (KD = kappa OFF/kappa ON) rather than by a Michaelis-Menten constant (KM = (kappa OFF + kappa TRANSLOCATION)/KAPPA ON). 相似文献
29.
A T Bankier W Dietrich R Baer B G Barrell F Colbre-Garapin B Fleckenstein W Bodemer 《Journal of virology》1985,55(1):133-139
30.
Jean Bernard Dietrich 《Bioscience reports》1985,5(2):137-142
Western blotting was used as a powerful alternative to immunoprecipitation for the detection of the simian virus 40 (SV40) large tumor (T) antigen. After resolution by electrophoresis on a SDS-polyacrylamide gel of a [15S]methionine labeled crude extract from SV40 infected monkey kidney cells, the separated proteins were transferred electrophoretically on nitrocellulose paper. T antigen was detected on nitrocellulose strips by using for the first time, specific, purified antipeptide monoclonal antibodies directed against the N- and C-terminal portions of the molecule, and125I-labeled Protein A. 相似文献