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71.
Targeted immunotherapy utilizing monoclonal antibodies has improved survival in both indolent and aggressive lymphoma significantly. Since malignant lymphomas are also responsive to radiation, the combination of targeted immunotherapy and radiation with radionuclide coupled to monoclonal antibodies is an attractive option to further improve treatment results. Zevalin is a commercially available variation of the murine anti-CD20 antibody ibritumomab coupled to Yttrium 90 via the tiuxetan chelator. The development of this novel drug as well as the results of the pivotal studies and clinical strategies to implement this treatment into the routine practice of lymphoma oncology are presented in this review. 相似文献
72.
Forest health status in Europe is assessed by the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests). Established by the Convention on Long-Range Transboundary Air Pollution (CLRTAP) under the United Nations Economic Commission for Europe (UNECE), the ICP Forests has been monitoring forest condition in close cooperation with the European Commission (EC) for 20 years. The present paper describes the latest results of the deposition measurements on permanent monitoring plots and of the extensive defoliation sample survey. The findings reveal marked spatial patterns in bulk and throughfall depositions of nitrate (N-NO3(-)), ammonium (N-NH4(+)), and sulfate (S-SO4(2-)), as well as an obvious decrease in bulk and throughfall deposition of sulfate. Latest analyses of defoliation data confirm previous results, indicating a high correlation with weather extremes. 相似文献
73.
Michal Lorenz Brygida Bisikirska Beata Hanus-Lorenz Kazimierz Strzalka Aleksander F. Sikorski 《Cell biology international》1995,19(7):625-632
It was found either in Western-blot analysis or in indirect immunofluorescence microscopy that cells of the alga Chlamydomonas reinhardtii contain polypeptides cross-reacting with antibodies directed against red blood cell spectrin. The protein could also be detected by immunoprecipitation with anti-spectrin antibodies. C. reinhardtii cells contain distinct polypeptide chains reacting with antibodies directed against either α- or β-spectrin subunits. This protein was extracted from the cells with low ionic strength solution but was not with nonionic detergent. 相似文献
74.
Lorenz Gygax 《Ethology : formerly Zeitschrift fur Tierpsychologie》2000,106(5):441-451
In an observational study on captive long-tailed macaques ( Macaca fascicularis ), the ability to hide was investigated in the social context of aggression. The use of five different types of hiding place during highly aggressive interactions was recorded and the choices of six different rank-sex classes were compared using an index of attractiveness of the different types of hiding place during highly aggressive interactions. There was no significant difference between the rank-sex classes in selection of the hiding places that could be connected with visibility: no specific location or type was preferred, either by the group as a whole or by any specific rank-sex class. Thus long-tailed macaques do not seem to hide shortly after aggressive interactions. 相似文献
75.
Wissinger B Gamer D Jägle H Giorda R Marx T Mayer S Tippmann S Broghammer M Jurklies B Rosenberg T Jacobson SG Sener EC Tatlipinar S Hoyng CB Castellan C Bitoun P Andreasson S Rudolph G Kellner U Lorenz B Wolff G Verellen-Dumoulin C Schwartz M Cremers FP Apfelstedt-Sylla E Zrenner E Salati R Sharpe LT Kohl S 《American journal of human genetics》2001,69(4):722-737
We recently showed that mutations in the CNGA3 gene encoding the alpha-subunit of the cone photoreceptor cGMP-gated channel cause autosomal recessive complete achromatopsia linked to chromosome 2q11. We now report the results of a first comprehensive screening for CNGA3 mutations in a cohort of 258 additional independent families with hereditary cone photoreceptor disorders. CNGA3 mutations were detected not only in patients with the complete form of achromatopsia but also in incomplete achromats with residual cone photoreceptor function and (rarely) in patients with evidence for severe progressive cone dystrophy. In total, mutations were identified in 53 independent families comprising 38 new CNGA3 mutations, in addition to the 8 mutations reported elsewhere. Apparently, both mutant alleles were identified in 47 families, including 16 families with presumed homozygous mutations and 31 families with two heterozygous mutations. Single heterozygous mutations were identified in six additional families. The majority of all known CNGA3 mutations (39/46) are amino acid substitutions compared with only four stop-codon mutations, two 1-bp insertions and one 3-bp in-frame deletion. The missense mutations mostly affect amino acids conserved among the members of the cyclic nucleotide gated (CNG) channel family and cluster at the cytoplasmic face of transmembrane domains (TM) S1 and S2, in TM S4, and in the cGMP-binding domain. Several mutations were identified recurrently (e.g., R277C, R283W, R436W, and F547L). These four mutations account for 41.8% of all detected mutant CNGA3 alleles. Haplotype analysis suggests that the R436W and F547L mutant alleles have multiple origins, whereas we found evidence that the R283W alleles, which are particularly frequent among patients from Scandinavia and northern Italy, have a common origin. 相似文献
76.
Newberry RD McDonough JS Stenson WF Lorenz RG 《Journal of immunology (Baltimore, Md. : 1950)》2001,166(7):4465-4472
77.
The question whether different organisms are able to compete for the same resource is of fundamental importance to evolutionary biology. Sympatric co-existence of similar species on a single resource has long been claimed to be unstable. However, indirect evidence suggests that parasitic wasps exhibit evolutionarily stable mixtures of life-history strategies. Here we describe genetically distinct strains of a parthenogenetic wasp Venturia canescens, with different ovarian phenotypes that affect egg numbers in oviducts. Wasp females with large egg load search for caterpillars and deposit eggs immediately after host encounter, whereas females with fewer eggs delay parasitism. Since the outcome of interlarval competition within super-parasitized caterpillars depends on the age distribution of competing larvae, the two egg deposition strategies may co-exist under conditions that favor super-parasitism. 相似文献
78.
Koutsovelkidis I Neopikhanov V Söderman C Lorenz A Uribe A 《Preparative biochemistry & biotechnology》1999,29(2):121-138
Bacterial constituents and products of the bacterial metabolism pass from the gut lumen to the portal vein and may influence the homeostasis of the liver. Our aim is to examine whether DNA synthesis of human hepatocyte cell lines is affected by constituents of Escherichia coli species as well as by intracolonic products of bacterial fermentation that reach the liver via the portal vein. Supernatant solutions and bacterial cell fractions (containing either whole dead bacteria, cell walls, cytosol or non-soluble intracellular components) of E. coli K12 and of E. coli species from rat fecal flora were separated by multi-step centrifugation, French press, and microfiltration. The supernatant solution and the cell fractions were incubated with a human hepatoma cell line (Hep-G2) and with a cell line derived from non-malignant human liver cells (Chang cells) for 24 h. The cells were labeled with tritiated thymidine before processing to autoradiography. DNA synthesis was estimated by the labeling index (LI%). DNA synthesis was also estimated following incubation of Hep-G2 cells with short chain fatty acids (acetic, propionic, butyric and succinic acid), acetaldehyde, and ammonium chloride. Epidermal growth factor and a water extract of Helicobacter pylori were used as references. The fractions of E. coli from rat fecal flora containing cytosol and non-soluble intracellular components significantly increased the labeling index in both Hep-G2 and Chang cells (p < 0.05). In addition, the supernatant solution significantly increased the LI in Chang cells (p < 0.05). Epidermal growth factor increased the LI of Hep-G2 cells dose-dependently (p < 0.05). Butyric acid reduced DNA synthesis at 10(-4) M (p < 0.05). The highest doses of acetaldehyde were cytotoxic and reduced the LI. Escherichia coli species contain mitogenic factors to human hepatocytes. The mitogen(s) are present in the supernatant solution, in the cytosol and in non-soluble intracellular components. Butyrate, which is a product of bacterial fermentation of colonic substrates inhibit DNA synthesis in the hepatocyte cell lines. Our findings suggest that soluble mitogen(s) that diffuse from the microorganism to the outer environment, intracellular bacterial constituents, and products of the bacterial metabolism that reach the liver via the portal vein may influence the cell kinetic steady-state of hepatic cells. 相似文献
79.
80.
Protein kinase CK2 is a pleiotropic Ser/Thr kinase occurring as alpha2beta2, alpha'2beta2, or alphaalpha'beta2 tetramers. A requirement in serum-stimulated cell cycle entry in both the cytoplasm and the nucleus of human fibroblasts for phosphorylation(s) by CK2 has been concluded from stimulation inhibition by microinjected antibodies against the regulatory subunit (beta). We have now examined this idea more directly by microinjection-mediated perturbation of phosphorylation and non-phosphorylation interactions of the catalytic subunits (alpha and alpha'), and by verifying the supposed matching of the cellular partition of CK2 subunits in the fibroblasts employed. While immunostaining and cell fractionation indicate that the partitions of subunits indeed match each other (with their predominant location in the nucleus in both quiescent and serum-stimulated cells), microinjection of substrate or pseudosubstrate peptides competing for the CK2-mediated phosphorylation in vitro resulted in significant inhibition of serum stimulation when placed into the nucleus but not when placed into the cytoplasm. Also inhibitory were nuclear but not cytoplasmic injections of antibodies against alpha and alpha' that affect neither their kinase activity in vitro nor their complexing to beta. The data indicate that the role played by CK2 in serum-stimulated cell cycle entry is predominantly nuclear and more complex than previously assumed, involving not only phosphorylation but also experimentally separable non-phosphorylation interactions by the catalytic subunits. 相似文献