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1.
We investigated the influence of the combined use of sizofiran, a-1,3-glucan and a recombinant interferon- (rIFN-) upon biological activities of peritoneal macrophages (M). The number of peritoneal M and the production of cytokines (interleukin-1, interferon- and tumor necrosis factor) was increased by the combined treatment. Fully activated peritoneal M based on the increased number of elongated pseudopods were observed by electromicroscope. Sizofiran seems to assure a sufficient supply of M to kill tumor cells in the peritoneal cavity and co-administered rIFN- seems to directly stimulate the accumulated M in addition to its direct cytotoxicity against tumor cells. This combination therapy may be a step to the prevention of the recurrence of gynecological malignancies including ovarian cancer, after a negative second-look laparotomy.Abbreviations rIFN- recombinant interferon- - IL-1 interleukin-1 - TNF tumor necrosis factor - SLL second look laparotomy  相似文献   

2.
    
Partial and total loss of function mutant alleles of a putative Drosophila homologue (DPhK-) of the vertebrate phosphorylase kinase -subunit gene have been isolated. DPhK- is required in early embryonic processes, such as gastrulation and mesoderm formation; however, defects in these processes are seen only when both the maternal and zygotic components of DPhK- expression are eliminated. Loss of zygotic expression alone does not appear to affect normal embryonic and larval development; some pupal lethality is observed but the majority of mutant animals eclose as adults. Many of these adults show defects in their leg musculature (e.g. missing and degenerating muscles), in addition to exhibiting melanised tumours on their leg joints. Loss of only the maternal component has no obvious phenotypic consequences. The DPhK gene has been cloned and sequenced. It has an open reading frame (ORF) of 1680 by encoding a 560 amino acid protein. The predicted amino acid sequence of DPhK- has two conserved domains, the catalytic kinase and calmodulin-binding domains, separated by a linker sequence. The amino acid sequence of DPhK- is homologous to that of mammalian PhK- proteins but differs in the length and amino acid composition of its linker sequence. The expression of DPhK- mRNA is developmentally regulated. We discuss the implications of these observations.  相似文献   

3.
Of 147 microorganisms isolated from a loamy sand, 71 showed good growth with lindane (-1,2,3,4,5,6-hexachlorocyclohexane) and produced chloride in an aqueous medium. Thirteen soil microorganisms were selected to study the utilization of lindane. Lindane was metabolized by the microbes to -2,3,4,5,6-pentachloro-1-cyclohexene (-PCCH), -3,4,5,6-tetrachloro-1-cyclohexene (-TCCH), -3,4,5,6-tetrachloro-1-cyclohexene (-TCCH), -3,4,5,6-tetrachloro-1-cyclohexene (-TCCH), and pentachlorobenzene (PCB). Cells of Pseudomonas sp. No. 62 grown on lindane simultaneously adapted to -PCCH, -TCCH, -TCCH, -TCCH, PCB, 1,2,3,4-tetrachlorobenzene (1,2,3,4-TCB) and 1,2,4,5-tetrachlorobenzene (1,2,4,5-TCB). The bacteria degraded each of these chemicals at least partially as indicated by an increased rate of oxygen consumption.Abbreviations Lindane -1,2,3,4,5,6-hexachlorocyclohexane - -PCCH -2,3,4,5,6-pentachloro-1-cyclohexene - -TCCH -3,4,5,6-tetrachloro-1-cyclohexene - -TCCH -3,4,5,6-tetrachloro-1-cyclohexene - -TCCH -3,4,5,6-tetrachloro-1-cyclohexene - PCB pentachlorobenzene - 1,2,3,4-TCB 1,2,3,4-tetrachlorobenzene - 1,2,3,5-TCB 1,2,3,5-tetrachlorobenzene - 1,2,4,5-TCB 1,2,4,5-tetrachlorobenzene - 1,2,3-tCB 1,2,3-trichlorobenzene - 1,2,4-tCB 1,2,4-trichlorobenzene - 1,3,5-tCB 1,3,5-trichlorobenzene - 1,2-DCB 1,2-dichlorobenzene - 1,3-DCB 1,3-dichlorobenzene - 1,4-DCB 1,4-dichlorobenzene - MCB monochlorobenzene Contribution No. 631, Research Institute, Agriculture Canada, University Sub Post Office, London, Ontario N6A 5B7  相似文献   

4.
Clostridium rectum strain S-17 converts -1,2,3,4,5,6-hexachlorocyclohexane (HCH) related compounds to chlorobenzenes. The metabolites from -1,2,3,4,5,6-hexachlorocyclohexene and -1,3,4,5,6-pentachlorocyclohexene are identified as 1,2,4-trichlorobenzene and 1,4-dichlorobenzene, respectively. ATP synthesis, converting these chlorinated compounds, is observed in the cell suspension of C. rectum as indicated by luciferase-luciferin reaction and phosphorylation of 32P-labeled phosphate. These observation lead to the conclusion that HCH and related compounds serve as artificial electron acceptors of the Stickland reaction, and therefore, the reductive dechlorination is associated with ATP synthesis.Abbreviations HCH -1,2,3,4,5,6-hexachlorocyclohexane - HCCH -1,2,3,4,5,6-hexachlorocyclohexene - PCCH -1,3,4,5,6-pentachlorocyclohexene - TCCH -3,4,5,6-tetrachlorocyclohexene - 1,2,4-TCB 1,2,4-trichlorobenzene - 1,4-DCB 1,4-dichlorobenzene - MCB monochlorobenzene - DTT 1,4-dithiothreitol - IAA monoiodoacetic acid  相似文献   

5.
For lindane degradation, a cell suspension of Clostridium rectum strain S-17 demands the addition of substrates such as leucine, alanine, pyruvate, a leucine-proline mixture, and molecular hydrogen. In the presence of leucine-proline mixture, lindane decomposed in parallel with isovaleric acid formation, and both lindane degradation and isovaleric acid formation were inhibited by monoiodoacetic acid, suggesting a close relation between lindane degradation and the Stickland reaction. Lindane was degraded by cell-free extracts of C. rectum in the presence of dithiothreitol (DTT). Radiogaschromatograms of n-hexane soluble metabolites from [14C] lindane showed the presence of monochlorobenzene and -3,4,5,6-tetrachlorocyclohexene, Leucine, NADH, and NADPH were somewhat less active than DTT for lindane degradation in cell-free extracts. Reductive dechlorination seemed the major route of lindane degradation in cell-free extracts as well as in the intact cells of C. rectum.Abbreviations Lindane (-HCH) -1,2,3,4,5,6-hexachlorocyclohexane - -HCH -1,2,3,4,5,6-hexachlorocyclohexane - -TCH -3,4,5,6-tetrachlorocyclohexene - -PCH -1,3,4,5,6-pentachlorocyclohexene - DTT 1,4-dithiothreitol  相似文献   

6.
Cytokines have great potential in the treatment of primary immunodeficiencies, which is just beginning to be realized. We discuss some general considerations in the use of cytokines in this setting, and review the clinical use of a number of cytokines. The best proven example to date is the use of interferon- in chronic granulomatous disease, which significantly reduces infectious complications of this disease. We also discuss the potential use of interferon- in the hyperimmunoglobulin E syndrome and in newborns. Granulocyte-colony stimulating factor usage in congenital neutropenias is reviewed. The use of IL-2, thymic hormones, and interferon- are briefly discussed. Strategies for the design of clinical trials of cytokines in these uncommon illnesses are proposed.Abbreviations ANC absolute neutrophil count - CGD chronic granulomatous disease - CSF colony-stimulating factor - CVID common variable immune deficiency - G-CSF granulocyte colony-stimulating factor - GM-CSF granulocyte-macrophage colony-stimulating factor - HIE hyperimmunoglobulinemia E - IL interleukin - NBT nitroblue tetrazolium - SCID severe combined immune deficiency - Th1, Th2 T helper type 1 and type 2  相似文献   

7.
180 rainbow trouts (Salmo gairdneriRich.), aged from 1 to 3 years, were examined for fluctuations, caused by age and season, by means of colour index (CI), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC).CI and MCH behave similarly. Both are increasing until the 2nd year and stay relatively constant thereafter. If the gender is not considered — there are no significant differences in the values of males and females — the CI increases from 1,4 in the first year over 1,6 to 1,7 in the age of 3 years, and the MCH increases from 44,4 over 52,6 , 56,8 , 58,1 to 55,5 .A seasonal periodicity of both indices could not be indicated on not-matured animals (F2) which were two summers of age. Only, the january values appeared increased — CI: 2, MCH: 68,3 — otherwise the CI varies between 1,8 and 1,7 and the MCH between 53,3 and 59,1 .The MCHC-values of the age groups examined vary between 24,4% and 27,3%. The values of the yearlings form an exception (19,8%). These values certainly are inexact and too low because of the small number of individuals checked (3).

Mit finanzieller Unterstützung durch die DFG.Institut für Siedlungswasserbau und Wassergütewirtschaft der Universitat Stuttgart Fischtoxikologische Arbeitsgruppe  相似文献   

8.
T-cell clones expressing the T-cell receptor (Tcr) were generated from peripheral blood lymphocytes (PBLs) and from a thymus sample. In the panel of ten thymus-derived clones, four Tcr phenotypes [as defined by the reaction of monoclonal antibodies (mAbs) directed against known V and V regions] were identified. All the clones lacked expression of the V3 V region, while seven clones were V1+ . V1 was found in combination with V9 or with undefined VVregions. In addition, two other Tcr phenotypes were identified on these clones: V9+ V1 V3 and V9 V1 V3 One of the clones expressed CD4 and another was CD8positive. The remaining clones were CD4 CD8. In the panel of 76 PBL-derived, Tcr-bearing clones, five Tcr phenotypes could be identified. In contrast to the thymus-derived clones, 30% of the clones were V3+ whereas V1 was expressed by a minority of the clones only. One clone was CD4-positive and approximately 30% of the clones were CD8-positive. Four of the five mAb-defined Tcr phenotypes could be identified on both thymus and PBL-derived T-cell clones. However, biochemical analysis of the Tcrs demonstrates differences in the usage of Ct- and C2-encoded y chains by T cells derived from the thymus and PBLs. The results therefore indicate that, at the clonal level, similarities and differences exist between the Tcr repertoires expressed in the thymus and by PBLs. Furthermore, they indicate that combinatorial Tcr heterogeneity is larger than has so far been described. The receptor diversity, combined with the potential of Tcr+ cells to express CD4 or CD8, indicates that these cells are a heterogeneous population that might mediate a number of immune functions.  相似文献   

9.
Microsomal vesicles prepared from etiolated hypocotyl tissue of zucchini (Cucurbita pepo L. cv. All Green Bush) exhibited saturable N-1-naphthylphthalamic acid ([3H]NPA) binding, NPA-stimulated association of indol-3yl-acetic acid ([3H]IAA), and saturable binding of guanosine 5-O-[3-thiotriphosphate] (GTP--[35S]). These vesicles were used to test the possibility that NPA receptors might interact with IAA-anion efflux carriers by coupling through a GTP-binding protein (G-protein). Unlabelled GTP--S or guanosine 5-O-[2-thiodiphosphate] (GDP--S) had no effect on saturable NPA binding or on the NPA-stimulated association of IAA with microsomes. NPA did not affect saturable binding of GTP--[35S] to microsomes, either in the presence or absence of saturating concentrations of unlabelled GTP--S or GDP. It is concluded that the occupancy of phytotropin receptors is not transduced to auxin efflux carriers by a GTP-binding protein.  相似文献   

10.
Replacement of unlabeled -butyrobetaine with -[2,3,4-2H6]butyrobetaine has a profound effect on the stoichiometry between decarboxylation of 2-oxoglutarate and hydroxylation in the reaction catalyzed by human -butyrobetaine hydroxylase. The ratios between decarboxylation and hydroxylation are 1.16 with Unlabeled and 7.48 with deuterated -butyrobetaine as substrate. From these ratios an internal isotope effect of 41 has been calculated. DV in the overall reaction measured as 2- oxoglutarate decarboxylation is 2.5 and DV/K is 1.0. For -butyrobetaine hydroxylase fromPseudomonas sp. AK 1, 2-oxoglutarate decarboxylation exceeds hydroxylation with 10% when deuterated -butyrobetaine is used. No excess was found with unlabeled substrate and no internal isotope effect could be calculated. DV for the bacterial enzyme is 6.  相似文献   

11.
Zeins from Zea mays L cv. Maya and coixins from Coix lacryma-jobi L. cv. Adlay were fractionated to obtain -, -, and -zein and -, -, and -coixin. The -coixins were composed of 4 polypeptide classes of 27 kDa (C1), 25 kDa (C2), 17 kDa (C4) and 15 kDa (C5) with solubility properties very similar to those of the 22 kDa and 19 kDa -zeins. Like the -zeins, the C1 and C2 -coixins corresponded to 80% of total Coix prolamins. The fraction corresponding to -coixin contained only one protein band of 22 kDa (C3). This coixin fraction has solubility properties similar to those of -zein and represents 15% of the total coixin. The -zein fraction was composed of a major 17 kDa protein band, while the -coixin fraction consisted of a mixture of - and -coixins.Polyclonal antibodies raised against C1 recognized C1 and C2 and cross-reacted strongly with the 22 kDa -zein, as did C4 and C5 antisera. The antiserum against -coixin showed strong cross-reaction with -zein. The homology between coixins and zeins was further investigated by using Southern hybridization analyses. The genomic DNA of maize and Coix were digested with several restriction enzymes and probed with cDNA clones representing 19 and 22 kDa -zeins as well as the 28 and 16 kDa -zeins. The Coix genome showed complex cross-hybridization sequences with the 22 kDa -zein cDNA, while no cross-hybridization was observed with the 19 kDa cDNA clone. The cDNA clone representing the 28 kDa -zein cross-hybridized with only one band of Coix genomic DNA, in contrast to the three bands observed in maize. This same Coix sequence also cross-hybridized with the cDNA clone representing the 16 kDa -zein. The relevance of these findings are discussed in the context of the origin of zein and coixin genes.  相似文献   

12.
Summary The regulation of the expression of indoleamine 2,3-dioxygenase (IDO) was studied in cloned murine macrophages (MT2) and microglial (N11) cells. Both cell lines express IDO and inducible nitric oxide synthase activity after interferon- (IFN-) stimulation. The regulation of IDO expression appears to differ in the two cell lines. Nitric oxide (NO) production negatively modulates the expression of IDO activity in IFN--primed macrophages, thereby indicating a cross-talk between the kynurenine and nitridergic pathways in these cells. Conversely, this down-regulation of IDO activity by NO does not occour in microglial cells. A differential regulation of IDO expression in the two cell lines was also observed with LPS and picolinic acid. Together with previous findings, these results indicate the existence of marked differences in the regulation of the expression of the kynurenine pathway enzymes between macrophages and microglial cells.Abbreviation used IFN- interferon- - IDO indoleamine 2,3-dioxygenase - NO nitric oxide - iNOS inducible nitric oxide synthase - NAME N-())-nitro-L-arginine methyl ester - SMTC S-methyl-L-thiocitrulline - BNI 3-bromo-7-nitroindazole - PIC picolinic acid - IL interleukin  相似文献   

13.
Summary Plasma membranes were prepared from soybean hypocotyls and roots by aqueous two-phase partitioning and subsequent free-flow electrophoresis. The highly purified plasma membranes bound [35S]GTPS with a relatively high affinity (Kd10nM). The binding was saturable and specific as it was indicated by the displacement of bound [35S]GTPS by unlabeled GTPS and GTP, but not by ATPS, ATP, UTP or CTP. ITP was intermediate in its ability to displace [35S]GTPS. When soybean plasma membrane proteins were separated by SDS-PAGE and displayed by autoradiography, two major [35S]GTPS binding proteins were revealed with apparent molecular weights of 24 and 28 kDa. Results with plasma membranes from soybean hypocotyls and roots were similar but differed from those with plasma membranes prepared from rat liver and adipocytes where only a single major [35S]GTPS binding activity with a molecular weight of 28 kDa was observed.Abbreviations 2,4-D 2,4-dichlorophenoxyacetic acid - G protein hetero-trimeric GTP binding protein with , , subunits - Gn protein GTP binding protein detected on nitrocellulose blots - GTPS guanosine 5-[-thio]triphosphate - IAA 3-indoleacetic acid - SDS-PAGE sodium dodecylsulfate-polyacrylamide gel electrophoresis  相似文献   

14.
Summary The storage proteins of the endosperm of wheat grain which are known to be controlled by genes on the short arms of the homoeologous group 1 chromosomes are (1) the -gliadins, (2) most of the -gliadins, (3) a few -gliadins and (4) the major lowmolecular-weight subunits of glutenin. Several crosses were made between varieties or genetic lines which had contrasting allelic variants for some of these proteins and which were coded by genes on chromosomes 1A or 1B. The progeny were analysed by one or more of several electrophoretic procedures. The results of all the analyses are consistent with the hypothesis that chromosomes 1A and 1B each contain just one, complex locus, named Gli-A 1 and Gli-B 1 respectively, which contain the genes for the -, - and -gliadins and the low-molecular-weight subunits of glutenin.  相似文献   

15.
The degradation of the phenylcoumaran substructure model compound methyl dehydrodiconiferyl alcohol by the white-rot wood decay fungus Phanerochaete chrysosporium was investigated using culture conditions optimized for lignin oxidation. Initial attack was in the cinnamyl alcohol side chain, which was oxidized to a glycerol structure. This was subsequently converted by loss of the two terminal carbon atoms, C and C, to yield a C-aldehyde structure, which was further oxidized to the C-acid compound. The next detected intermediate, a phenylcoumarone, was produced by double bond formation between C and C, and oxidation of the C-alcohol to an aldehyde group. Further oxidation of C to an acid yielded the next intermediate. The final identified degradation product was veratric acid. No products from the 5-substituted aromatic ring, and no phenolic products, were found. The initial glycerol-containing intermediate was a mixture of the threo and erythro forms, and no optical activity could be found, suggesting that its formation might have involved nonstereospecific C-C epoxidation followed by non-enzymatic hydrolysis of the epoxide.Abbreviations TLC thin layer chromatography - LDA lithium diisopropyl amide - DDQ 2,3-dichloro-5,6-dicyanobenzoquinone - MS mass spectrometry - UV ultraviolet spectroscopy  相似文献   

16.
Three -glutamyltranspeptidase (enzymes I, II and III) were partially purified from the cell free extracts of the cultured mycelia of Morchella esculenta Fr. The molecular masses of enzymes were 155,000 (I), 219,000 (II) and 102,000 (III). All of them catalyzed both hydrolysis and transpeptidation of various -glutamyl compounds. -l-Glutamyl-cis-3-amino-l-proline occurring in the cultured mycelia of this fungus was a good substrate for both reactions. K m values for hydrolysis were in the order of 10-4 to 10-5 M, and those for transpeptidation were in the order of 10-2 to 10-4 M. The enzymes were inhibited by a -glutamyltranspeptidase inhibitor, l-serine plus borate.Abbreviations -GTP -glutamyltranspeptidase - HPLC High-performance liquid chromatography  相似文献   

17.
A catalytic fragment, 1-298, derived from limited chymotryptic digestion of phosphorylaseb kinase (Harris, W.R.et al., J. Biol. Chem., 265: 11740–11745, 1990), is reported to have about six-fold greater specific activity than does the subunit-calmodulin complex. To test whether there is an inhibitory domain located outside the catalytic core of the subunit, full-length wild-type and seven truncated forms of were expressed inE. coli. Recombinant proteins accumulate in the inclusion bodies and can be isolated, solubilized, renatured, and purified further by ammonium sulfate precipitation and Q-Sepharose column. Four out of seven truncated mutants show similar ( 1-353 and 1-341) or less ( 1-331 and 1-276) specific activity than does the full-length wild-type , 1-386. Three truncated forms, 1-316, 1-300, and 1-290 have molar specific activities approximately twice as great as those of the full-length wild-type and the nonactivated holoenzyme. All recombinant s exhibit similarK m values for both substrates, i.e., about 18M for phosphorylaseb and about 75 M for MgATP. Three truncated s, 1-316, 1-300, and 1-290, have a 1.9- to 2.5-fold greater catalytic efficiency (V max/K m) than that of the full-length wild-type and a 3.5- to 4.5-fold greater efficiency than that of the truncated 1-331. This evidence suggests that there is at least one inhibitory domain in the C-terminal region of , which is located at 301-331· 1-290, but not 1-276, which contains the highly conserved kinase domain, is the minimum sequence required for the subunit to exhibit phosphotransferase activity. Both 1-290 and 1-300 have several properties similar to full-length wild-type , including metal ion responses (activation by free Mg2+ and inhibition by free Mn2+) pH dependency, and substrate specificities.  相似文献   

18.
Summary A search of sequence databases shows that spherulin 3a, an encystment-specific protein ofPhysarum polycephalum, is probably structurally related to the - and -crystallins, vertebrate ocular lens proteins, and to Protein S, a sporulation-specific protein ofMyxococcus xanthus. The - and -crystallins have two similar domains thought to have arisen by two successive gene duplication and fusion events. Molecular modeling confirms that spherulin 3a has all the characteristics required to adopt the tertiary structure of a single -crystallin domain. The structure of spherulin 3a thus illustrates an earlier stage in the evolution of this protein superfamily. The relationship of - and -crystallins to spherulin 3a and Protein S suggests that the lens proteins were derived from an ancestor with a role in stressresponse, perhaps a response to osmotic stress.  相似文献   

19.
The effects of lipids on the glycosylation of recombinant human interferon- expressed in a Chinese Hamster Ovary cell line were investigated in batch culture. Lipids form an essential part of the N-glycosylation pathway, and have been shown to improve cell viability. In control (serum-free) medium the proportion of fully-glycosylated interferon- deteriorated reproducibly with time in batch culture, but the lipoprotein supplement ExCyte was shown to minimise this trend. Partially substituting the bovine serum albumin content of the medium with a fatty-acid free preparation also improved interferon- glycosylation, possibly indicating that oxidised lipids carried on Cohn fraction V albumin may damage the glycosylation process.Abbreviations BSA bovine serum albumin - CHO chinese hamster ovary - DHFR dihydrofolate reductase - FCS foetal calf serum - IFN- human interferon-gamma - q IFN specific interferon production rate - specific growth rate - 2N doubly-gycosylated - 1N singly-glycosylated - ON non-glycosylated  相似文献   

20.
Various Spirulina strains were assayed for their productivity of -linolenic acid (Lnn). Spirulina platensis ARM-346 was found to accumulate large amounts of Lnn. Urea as a nitrogen source was found to be most effective giving a yield of 13.5 mg Lnn/g dry cell mass. With increase in temperature the Lnn content was found to increase along with biomass. The optimum temperature for maximum Lnn and biomass production was found to be 35°C. The Lnn content was highest at 0.06% (w/v) NaCl and 0.07% (w/v) K2HPO4. Cells cultivated in the orange region of the electromagnetic spectrum as energy source showed a high content of Lnn, and there was less biomass compared to cells grown in red light. When the culture was left in the dark for various times, after 144 h it contained about 26% more Lnn than in conventionally cultivated cells.  相似文献   

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