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1.
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   

2.
We have isolated an unusual T cell receptor chain cDNA clone (7.1) from a library made from RNA derived from adult thymus of C57BL/Ka mice. This cDNA clone corresponds to the appropriately processed C1 constant region exons preceded by 1.5 kb of J-C1 intron. The 7.1 coding region is extremely homologous to the C1 gene of BALB/c mice, differing at the protein level by a single deletion (alanine 139) and a single substitution. This latter change eliminates the sole N-linked sugar attachment site, providing a basis for strain-specific glycosylation patterns. The J-C1 intronic region contains two DNA segments (termed J1 and J2) that are highly reminiscent of joining (J) segments; both have potentially functional recombination and donor splice sequences flanking an open reading frame. Northern analysis suggests that 7.1 may be derived from a large, variable region-containing precursor.  相似文献   

3.
Summary Human blood monocytes were isolated by counter-flow centrifugal elutriation from healthy donors and these noncytotoxic monocytes were rendered tumoricidal to allogeneic melanoma (A375) cells by activation with a synthetic acyltripeptide (FK-565), as assessed by measuring release of [125I]iododeoxyuridine in 72 h. When monocytes were treated with FK-565 for 16 h, and then fixed with paraformaldehyde, they showed cytotoxicity to A375 melanoma cells. The fixed-monocyte-mediated cytotoxicity to A375 cells was induced by the synergistic actions of FK-565 and recombinant interferon- (rIFN-), but not other cytokines [rIFN-A, rIFN-, tumor necrosis factor (TNF), interleukin (IL)-2, -3 and -6]. For synergistic activation of monocytes with induction of a membrane-associated antitumor monokine, the monocytes had to be incubated first with rIFN- and then with FK-565. FK-565 also acted synergistically with rIFN- to stimulate monocytes to produce membrane-associated IL-1 activity, which induced C3H/HeJ thymocyte blastogenesis in response to phytohemagglutinin P. The tumoricidal and thymocytestimulating activities of the fixed monocytes were almost completely inhibited by a specific anti-(IL-1) antiserum, but not by a specific anti-(IL-1) antiserum or monoclonal anti-TNF antibody. These results suggest that membrane-associated IL-1 of human blood monocytes can be induced by two activation signals (rIFN- then FK-565) at their suboptimal concentrations.Abbreviations IL interleukin - IFN interferon - TNF tumor necrosis factor  相似文献   

4.
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   

5.
Summary The 7S nerve growth factor molecule, found in the mouse submandibular gland, is comprised of three distinct protein subunits named , and -NGF. In this paper, radioimmunoassays specific for each subunit were used to measure the concentrations of these subunits in homogenates of mouse submandibular gland. It was determined that there were excess concentrations of both the and subunits, more than enough to bind all of the -NGF in the gland to form 7S-NGF. The radioimmunoassay data was confirmed by gel filtration experiments. In the gel filtration experiments, the excess and subunits eluted at positions which would indicate that these excess subunits were free and not bound in the 7S-NGF complex. The identity of the excess and subunits was substantiated by ion exchange chromatography, isoelectric focusing polyacrylamide gels and immunoblotting experiments. In conclusion, there are considerable quantities of and subunits present in the submandibular gland which are not bound to -NGE The functional significance of these excess concentrations of the and subunits is not known.  相似文献   

6.
Screening studies with strict and facultative anaerobic bacteria showed that Clostridium app. and several other representatives of Bacillaceae and Enterobacteriaceae actively degraded -hexachlorocyclohexane (-HCH) under anaerobic conditions. Representatives of Lactobacillaceae and Propronibacterium were inactive. With 36Cl-labelled -HCH a nearly complete dechlorination was shown to occur in 4–6 days by Clostridium butyricum, C. pasteurianum and Citrobacter freundii, while other facultative anaerobic species were less active.Aerobically grown facultative anaerobes also dechlorinated actively -HCH during subsequent anaerobic incubation with glucose, pyruvate or formate as substrates. The -, - and -HCH isomers were also, but more slowly, dechlorinated (>>-HCH). All species active in anaerobic degradation of -HCH formed -tetrachlorocyclohexene (TCH) as the main intermediate metabolite and no -pentachlorocyclohexene (PCH) or other isomers of TCH or PCH have been found. Small amounts of tri- and tetrachlorinated benzenes have been found too. The mechanism of dechlorination is discussed.Non-Common Abbreviations Used -HCH -hexachlorocyclohexane - -TCH -2,3,4,5-tetrachlorocyclohexene - -PCH -1,2,3,4,5-pentachlorocyclohexene - GLC gas liquid chromatography  相似文献   

7.
Summary Southern blotting and DNA sequencing after polymerase chain reaction (PCR) amplification provide evidence for the frequent occurrence (in 7 out of 24 chromosomes) of a short conversion GA in the 3 end of the human fetal A globin gene. This short conversion is characterized by the presence, 3 nucleotides downstream from the termination codon of the A gene, of the TCAC sequence that is normally present at the equivalent position at the 3 end of the G gene; it is therefore identical to a conversion already described. Interestingly, we have found that this conversion is associated with the presence of theHindIII polymorphic restriction site in the A IVS2, occuppying an equivalent position in both the G and A genes. Our observations strengthen the hypothesis that the presence of the HindIII polymorphic restriction site in A IVS2 and the presence of the sequence TCAC at the 3 end of the A gene might be the result of a single conversion event.  相似文献   

8.
A simple and rapid method, using only two chromatographic steps, is described for the purification and preparation of enolase isoenzymes from human and beef brain extracts. In the first step, a crude enolase was obtained by chromatography on Q-Sepharose Fast Flow column. The crude fraction was then purified by high performance anion exchange chromatography on a Mono-Q column. enolase obtained in this manner was shown to be homogeneous by two dimensional polyacrylamide gel electrophoresis and by high performance gel permeation chromatography. The yield of enolase by this method was 7–8 mg of pure enzyme per 100 g of brain.  相似文献   

9.
Molecular and Functional Studies of the Gamma Subunit of the Sodium Pump   总被引:6,自引:0,他引:6  
This article reviews our studies of the subunit of the sodium pump. is a member of the FXYD family of small, single transmembrane proteins and is expressed predominantly in the kidney tubule. There are two major variants of which function similarly to bring about two distinct effects, one on KATP and the other, on K K, the affinity of the pump for K + acting as a competitor of cytoplasmic Na+. In this way, is believed to provide a self-regulatory mechanism for maintaining the steady-state activity of the pump in the kidney. Our studies also suggest that K+ antagonism of cytoplasmic Na+ activation of the pump is relevant not only to the presence of in the kidney, but probably some hitherto undefined factor(s) in other tissues, most notably heart. The interesting possibility that not only but other members of the FXYD family regulate ion transport in a tissue-specific manner is discussed.  相似文献   

10.
Summary The -glucuronidase staining characteristics of isolated T cell populations and the T and T enriched fractions derived of them were studied. T lymphocytes were obtained from purified T lymphocytes by ox-IgG rosette sedimentation. The rosette-forming cells in the pellet were referred to as T lymphocytes, whereas the lymphocytes in the interface were referred to as T depleted or T lymphocytes. B cells were studied on rosetted mononuclear cells with either mouse erythrocytes or with Staphylococcus Aureus (Cowan I) bacteria, after a preceeding polyvalent anti-human Ig treatment of the cells. While B cells showed mostly no reactivity, T and T cells were respectively characterised by a dot-like and granular pattern of reactivity. These findings are in agreement with those observed by others after -naphthyl-acetate esterase or acid phosphatase staining. Within the T lymphocyte fraction, the T non-, non lymphocytes seemed to have a granular pattern of reactivity. The same staining pattern was found in non-B, non-T lymphocytes.  相似文献   

11.
Summary The occurrence of the AT chain (i.e. A75 Ile Thr) in different populations was evaluated through a study of 4250 cord blood samples and blood samples from more than 350 SS1 patients. High frequencies were observed in Italy, Yugoslavia, Turkey, Holland, but also in Japan, Vietnam, and India. The chain is (nearly) absent in the Black population of Ghana and Kenya, and low frequencies were observed in China and Australian aborigines. Only a few adult SS patients (18 out of 357) were AT heterozygotes. The chromosomes with the AT globin gene were mapped through an evaluation of the presence of 10 different restriction sites. The AT chromosomes from different populations were closely related and had the same subhaplotypes of [--++-+] (Hinc II 5 to ; Xmn I 5 to G; Hind III in G and A; Hinc II in and 3 to ), quite different from the subhaplotypes seen for AT negative chromosomes.2 This suggests a common ancestor which may have originated in Southern Europe. An evaluation of the chain production by both chromosomes in SS patients and -thalassemia heterozygotes was possible for subjects with an AT heterozygosity. It was concluded that in -thalassemia trait, the chain synthesis is directed for about two-thirds by the thalassemic chromosome and for about onethird by the normal chromosome; the contribution by the normal chromosome decreases with a decrease in total chain production.This is contribution #0890 of the Department of Cell and Molecular Biology, Medical College of Georgia, Augusta, GA 30912, USA  相似文献   

12.
    
A genomic clone encoding the -kafirin gene from sorghum was isolated and sequenced. A 2938 bp sequenced fragment includes an intronless open reading frame of 636 nucleotides encoding a putative polypeptide of 212 amino acids. Comparison of the deduced amino acid sequence of -kafirin with the published sequences of -prolamins of maize, and Coix revealed highly conserved domains. The N-terminal region of these proteins contains the conserved hexapeptide PPPVHL, which is repeated eight times in -zein, four times in -kafirin and three times in -coixin. The number of PPPVHL repeats accounts predominantly for the differences in the molecular weights of -prolamins. Several putative regulatory sequences common to the -kafirin and -zein genes were identified in both the 5 and the 3 flanking regions. Putative GCN4-like regulatory sequences were found at positions –192 and –476 in the 5 flanking region of -kafirin. In the 3 noncoding region, three putative polyadenylation signals, two AATAAT and one AATGAA, were found at positions + 658, + 716, and + 785, respectively. In order to investigate the role of the putative GCN4-like motifs and other possible cis-acting element(s) of the -kafirin promoter, a series of deleted and chimeric promoter constructs were introduced into maize, Coix and sorghum tissues by particle bombardment. Histochemical analysis of -glucuronidase (GUS) activity in different tissues indicated that the element(s) responsible for tissue specificity is probably located in the 285-bp proximal region of the promoter, while the remaining promoter sequence seems to carry the element(s) responsible for the quantitative response.The nucleotide sequence data reported in this paper appear in the EMBL/GenBank/DDBJ Nucleotide Sequence Databases under the accession number X62480  相似文献   

13.
The lineage to which normal large granular lymphocytes/natural killer (LGL/NK) cells belong is controversial; in fact they share some surface markers and functional activities with monocytes, but also with T lymphocytes. The relationship of LGL to the T cell lineage by analysis with the T cell receptor (T-rec) gene has been investigated. Pure preparations of human LGL and their CD11+ CD8- and CD11- CD8+ subsets had the T gene in its unrearranged germline configuration. Expression of T and T genes was not detectable. The organization of T gene, which is of particular importance because it occurs early in T cell ontogeny, was also found in its germline configuration.A rare type of lymphoproliferative disorder, termed T-LPD, is characterized by expansion of cells very similar to LGL for morphology, phenotype, and functional activity. Of 17 patients with T-LPD studied for T-rec rearrangement, 15 displayed rearrangement of T and T loci and were CD3+ (14/15 had monoclonal rearrangement), while 2 cases were in germline configuration and were CD3–. Similarly to very small subsets of CD3+ LGL recently described, most T-LPD cases are CD3+ and have T-rec genes rearranged. These data suggest that either a subset of LGL or a particular step of differentiation may be related to the T cell lineage; they also demonstrate that, in contrast to previous views, most TLPD are monoclonal, presumably neoplastic, lymphoproliferative disorders.Abbreviations LGL large granular lymphocytes - NK natural killer - T-rec T-cell receptor - TLPD T lymphoproliferative disease  相似文献   

14.
Interferon- (IFN-) and tumor growth inhibitory factor (TGIF) were inducedin vitro in the supernatant from mixed culture of human peripheral blood mononuclear cells (PBMC) and OK-432. TGIF activity was determined by growth inhibition of a human gastric adenocarcinoma cell line, MK-1 cells, and IFN- activity was measured by radioimmunoassay. The production of TGIF and IFN- was time-dependent, reaching its maximum around 48 hrs. Although there was no significant correlation between TGIF production and IFN- production, combination of a subthreshold concentration of recombinant IFN- (rIFN-) and TGIF induced significant growth inhibition of MK-1 cells. This fact indicates that the effects of rIFN- and TGIF are synergistic. The antiproliferative effect of these cytokines are highly species-specific, and their synergistic effects were also species-specific. rIFN--sensitive and -resistant clones were successfully established from the original MK-1 cell line; those clones are both sensitive to TGIF. Synergistic antiproliferative effects were found when the rIFN--sensitive clone, but not the resistant clone, was used as a target, suggesting that the synergistic effects require the target cells' sensitivity to IFN-. These results indicate that the synergistic effects of TGIF and IFN- may produce a clinical antitumor action in cancer patients receiving OK-432 administration.  相似文献   

15.
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   

16.
In previous studies, we isolated and identified a -calpain/PKC complex from rabbit skeletal muscle. Here, we have used specific purification procedures in order to study the interactions between -calpain and PKC in mouse hippocampus, a brain structure implicated in memory processes. We observed that -calpain and conventional PKCs (, II and ) are co-eluted after anion exchange chromatography. In contrast to our previous results obtained on skeletal muscle, -calpain and PKC isoenzymes were dissociated after gel filtration chromatography. Furthermore, -calpain induced the proteolytic conversion of PKC, II, and into PKM, II, and with a preferential hydrolysis of PKC, a specific isoenzyme of the nervous system. Although the -calpain/PKC interactions in the hippocampus are quite different from skeletal muscle, our results however, point out the functional importance of these inter-relations. Moreover, as PKC has been involved in the biochemical events underlying learning and memory, the preferential relationship between -calpain and PKC promotes the importance of the role that -calpain could play in the cellular mechanisms of memory formation.  相似文献   

17.
Summary We recently reported that interleukin-2(IL-2)-activated peripheral blood lymphocytes and CD3+, lymphokine-activated killer (LAK) cell clones release tumor necrosis factor (TNF) and interferon (IFN) when stimulated with K562 erythroleukemia cells. We examined the phenotype of IL-2-activated peripheral blood leukocytes that secrete TNF and IFN when stimulated with K562 cells and demonstrated that TNF secretion is not due to the presence of contaminating mononuclear phagocytes. Further, we demonstrate that IL-2-activated natural killer (NK) cells release only IFN when stimulated with K562 cells while T lymphocytes exposed to monoclonal anti-CD3 and K562 cells secrete both TNF and IFN. However, T cells stimulated only with K562 cells did not release IFN or TNF while the admixture of these T cells with NK cells, when stimulated with K562 cells, released levels of TNF comparable to those produced by the unseparated cells. At present it is unclear whether only one or both effector cell types respond to K562 by releasing TNF or why the presence both cell types is needed.This work was supported by grants from the national Institutes of Health (CA 23074 and CA 17094) and the Arizona Disease Commission (8277-000000-1-0-YR-9301)  相似文献   

18.
Summary Callus cultures were established from Cephalotaxus harringtonia (Japanese plumyew) stem expiants cultured on Murashige and Skoog medium supplemented with 4.5 M 2,4-dichlorophenoxyacetic acid and 0.05 M 6-furfurylaminopurine. The inclusion of 4.9 M 6-(,-dimethylallylamino) purine as the sole hormone significantly increased the growth rate of the callus. Organogenesis giving rise to both shoots and roots occurred upon transfer of the callus onto a hormonefree medium. Vitrification was common on all regenerated shoots cultured on Gelrite-containing medium. Regenerated roots were excised and established in McCown's woody plant medium. Doubling the phosphate and nitrate levels in the medium increased the growth of these root cultures.Abbreviations MS Murashige and Skoog basal medium - B5 Gamborg's B5 basal salt medium - WP McCown's woody plant basal salt medium - 2,4-D 2,4-dichlorophenoxyacetic acid - Kinetin 6-furfurylamino-purine - 2iP 6-(,-dimethylallylamino) purine - IBA indole-3-butyric acid  相似文献   

19.
The effect of various concentrations of natural and chemically modified cyclodextrins on the luminescence of an Escherichia coli suspension was investigated. All cyclodextrins were found to reduce, albeit to a varying degree, the luminescence level of the bacterial cells, thus suggesting a direct interaction between the cyclodextrins and cells. The inhibitory concentrations IC20 and IC50 of the various cyclodextrins were determined and taken to represent their toxicity effects upon the bacterial cells. Among the natural cyclodextrins, - and -CD interfered minimally with the bacterial luminescence and consequently were essentially non-toxic. The following descending order of toxicity was observed: -CD -CD > -CD. Among the chemically modified cyclodextrins, Dimeb was clearly toxic while Trimeb and the hydroxylated derivatives (hydroxypropyl-ga-CD, HPACD;--CD, HPBCD;--CD, HPGCD) were essentially non-toxic. The following descending order of toxicity was observed: Dimeb HPBCD > Trimeb > HPACD > HPGCD.  相似文献   

20.
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   

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