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1.
Sally Engle Merry 《American anthropologist》2001,103(1):16-29
The new urban social order depends on a complex combination of systems of punishment, discipline, and security. Scholars drawing on Foucault's analysis of the art and rationality of governance, or govemmentality, have explored how urban social orders are increasingly based on the governance of space rather than on the discipline of offenders or the punishment of offenses. The new urban social order is characterized by privatized security systems and consumer-policed spaces such as malls. Gender violence interventions represent another deployment of spatial forms of govemmentality. Over the last two decades, punishment of batterers has been augmented by disciplinary systems that teach batterers new forms of masculinity and by security systems for women based on spatial separation. In the postmodern city, spatial govemmentality is integrally connected with punishment and discipline. These new forms of governance circulate globally along with neoliberal ideas of the diminished state, [gender violence, govemmentality, urban society, globalization, law] 相似文献
2.
Hybridoma cells containing intracellular anti-ricin antibodies show ricin meets secretory antibody before entering the cytosol 总被引:6,自引:0,他引:6
Hybridoma cells which synthesize monoclonal antibodies (mAb) that block ricin toxicity were 50-300-fold resistant to ricin compared with other hybridomas. Two of the mAb blocked two isozymes of ricin, D and E, to different and opposite extents, and the hybridoma cell resistance to the two forms of ricin closely corresponded with the mAb reactivity. The hybridoma cell resistance to ricin was therefore due to the binding activity of the mAb produced by the cells. Neither rabbit polyclonal antibodies, which neutralized extracellular anti-ricin mAb, nor quantitative removal of hybridoma cell surface IgG with papain affected the cellular resistance to ricin. Therefore, neither extracellular or cell surface antibodies contributed to the resistance of the hybridoma cells. In contrast, inhibition of protein synthesis by cycloheximide or puromycin, which selectively decreased levels of intracellular secretory IgG, decreased the hybridoma cell resistance to ricin. We conclude that intracellular mAb, synthesized de novo for subsequent secretion, block ricin toxicity. Ricin therefore must meet intracellular secretory antibodies before reaching the cytosol. The monoclonal antibodies can also be used to study toxin function within intracellular compartments. An antibody specific for the galactose-binding site of ricin blocks ricin intracellularly, showing that the ricin galactose-binding activity is required in an intracellular compartment for transport of ricin A chain to the cytosol. 相似文献
3.
Antitubulin immunofluorescent staining was used to examine the relationship among crystal formation, mitotic arrest, and recovery potential in vinblastine-treated Chinese hamster cells. Although vinblastine caused a mitotic block at concentrations as low as 5 x 10(-9) M, it induced tubulin crystal formation only at concentrations higher than 10(-6) M. At these higher concentrations, cells took 48-72 h to recover after return to normal medium. This extended period of time was apparently needed for breakdown of the crystals and regeneration of normal cytoplasmic microtubules. At concentrations less than 10(-6) M, although the mitotic block was still effective, no crystals were present. Possibly because of this lack of crystal formation, the cells recovered rapidly, generating cytoplasmic microtubules within 30 min, and beginning to undergo mitosis within 60 min. These findings tend to support biochemical evidence that tubulin binds to vinblastine at two types of binding site: a high affinity, low capacity site, responsible for tubulin disaggregation; and a low affinity site, responsible for protofilament splaying. 相似文献
4.
Application of a modified immunofluorescence technique using an anti-kinetochore serum enables cytogeneticists to obtain quality metaphase spreads and to localize kinetochores. In a patient with a 45, XX, -9, -11, tdic (9p;11p) constitution, we found that the dicentric marker chromosome has an intensely fluorescent kinetochore (no. 11), the functional centromere, and a less intensely fluorescent kinetochore (no. 9), the inactive centromere. The data suggest that in the process of tandem fusion (telomere-telomere between 11p and 9p), the centromere of chromosome 9 was not deleted, but, rather, inactivated. 相似文献
5.
F M Uckun R C Stong R J Youle D A Vallera 《Journal of immunology (Baltimore, Md. : 1950)》1985,134(5):3504-3515
We evaluated a novel ex vivo "purging" protocol for selective elimination of neoplastic T cells from human marrow by using a sensitive clonogenic assay. Immunotoxins (IT) were synthesized by conjugating ricin (R) to four different monoclonal antibodies (MoAb) directed against distinct markers of T cell lineage. Treatment with anti-p67-R produced effective elimination of leukemic T cells from human marrow. The cyclophosphamide congener mafosfamid (ASTA Z 7577) markedly enhanced the target cell cytotoxicity of IT and extended the final level of clonogenic kill 2 to 3 logs. Our data show that anti-p67-R in combination with mafosfamid resulted in a maximum elimination of 6.2 logs of neoplastic T cells with minimal toxicity to normal bone marrow progenitors. The efficiency of this protocol was not reduced in the presence of excess normal bone marrow cells. Similar findings were obtained by using a cocktail of four different anti-T cell IT. This approach is unique in combining both immunologic (IT) and chemical (mafosfamid) strategies for more effective ex vivo bone marrow purging in autologous bone marrow transplantation for T cell acute lymphoblastic leukemia/lymphoblastic lymphoma. 相似文献
6.
The effect of chronic and acute dietary restriction on the growth and protein turnover of fast and slow types of rat skeletal muscle 总被引:2,自引:0,他引:2
A J el Haj S E Lewis D F Goldspink B J Merry A M Holehan 《Comparative biochemistry and physiology. A, Comparative physiology》1986,85(2):281-287
Changes in the growth and protein turnover of the anterior tibialis and soleus muscles were studied in response to acute and chronic dietary restriction (50% of ad libitum intake) between 3 and 149 weeks post partum. The effect of long-term dietary restriction from weaning to senescence was to retard the growth and normal developmental of the two types of skeletal muscle. This was evident from measurements of various parameters of growth, i.e. total protein, RNA and DNA and protein/DNA-P, which were reduced by approximately 50% when compared with age-matched controls. These decreases, however, were not accompanied by a decline in the fractional rate of synthesis (%/day) or ribosomal activity (mg protein/day per mg RNAP). The slowing down of the age-related decline in muscle growth has been attributed to a reduction in RNA capacity (RNA/protein), with similar responses in the fast- and slow-twitch skeletal muscles. The initial effects of piecemeal feeding of this restricted diet on the two types of muscle were also monitored. Short term starvation effects, i.e. 24 hr after feeding a reduced ration, were measured on the protein content and RNA/protein of both the anterior tibialis and soleus muscles; both parameters were unchanged within 24 hr. In contrast, a rapid and significant decline in the ribosomal synthetic activity (mg/d per mg RNAP), and a corresponding fall in the fractional rate of synthesis, occurred within 24 hr of feeding. 相似文献
7.
Induction of apoptosis by La Crosse virus infection and role of neuronal differentiation and human bcl-2 expression in its prevention. 总被引:7,自引:6,他引:1
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La Crosse virus causes a highly cytopathic infection in cultured cells and in the murine central nervous system (CNS), with widespread neuronal destruction. In some viral infections of the CNS, apoptosis, or programmed cell death, has been proposed as a mechanism for cytopathology (Y. Shen and T. E. Shenk, Curr. Opin. Genet. Dev. 5:105-111, 1995). To determine whether apoptosis plays a role in La Crosse virus-induced cell death, we performed experiments with newborn mice and two neural tissue culture models. Newborn mice infected with La Crosse virus showed evidence of apoptosis with the terminal deoxynucleotidyl transferase-mediated nicked-end labeling (TUNEL) assay and, concomitantly, histopathological suggestion of neuronal dropout. Infection of tissue culture cells also resulted in DNA fragmentation, TUNEL reactivity, and morphological changes in the nuclei characteristic of apoptotic cells. As in one other system (S. Ubol, P. C. Tucker, D. E. Griffin, and J. M. Hardwick, Proc. Natl. Acad. Sci. USA 91:5202-5206, 1994), expression of the human proto-oncogene bcl-2 was able to protect one neuronal cell line, N18-RE-105, from undergoing apoptosis after La Crosse virus infection and prolonged the survival of infected cells. Nevertheless, expression of bcl-2 did not prevent eventual cytopathicity. However, a human neuronal cell line, NT2N, was resistant to both apoptosis and other types of cytopathicity after infection with La Crosse virus, reaffirming the complexity of cell death. Our results show that apoptosis is an important consequence of La Crosse virus infection in vivo and in vitro. 相似文献
8.
Two individuals with elliptocytic red cells apparently lack three minor erythrocyte membrane sialoglycoproteins. 总被引:9,自引:4,他引:5
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D J Anstee S F Parsons K Ridgwell M J Tanner A H Merry E E Thomson P A Judson P Johnson S Bates I D Fraser 《The Biochemical journal》1984,218(2):615-619
We have studied the erythrocytes of two individuals (P. L. and K. W.) who lack the Gerbich (Ge) blood-group antigen. The erythrocytes of P. L. and K. W. were not reactive with two monoclonal antibodies (NBTS/BRIC 4 and NBTS/BRIC 10) which reacted with normal erythrocytes. The membranes of P. L. and K. W. erythrocytes appeared to lack three minor sialoglycoproteins (beta, beta 1 and gamma). These three minor sialoglycoproteins were found to be associated with the cytoskeletons of normal erythrocytes. Approx. 10% of the erythrocytes of P. L. and K. W. were frankly elliptocytic. We suggest that one or more of the minor sialoglycoproteins may play a part in maintaining the discoid shape of the human erythrocyte. 相似文献
9.
The disulphide-bonded nature of procollagen and the role of the extension peptides in the assembly of the molecule.
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1. The molecular weights of chick tendon and cartilage procollagens, and their constituent polypeptides, were determined by gel filtration and gel electrophoresis. The values obtained are in good agreement and indicate that the mol.wts. of the secreted procollagens (types I and II) and their individual pro-alpha-chains are of the order of 405 000-445 000 and 137 000-145 000 respectively.2. Digestion of tendon procollagen with human rheumatoid synovial collagenase gave products consistent with the presence of large non-helical peptide extensions at both N-and C-termini. Electrophoretic analysis gave apparent mol.wts. of 17 500 and 36 000 for the respective N- and C-terminal extensions of pro-alpha1(I)-and pro-alpha2-chains, and inter-chain disulphide bonds were restricted to the C-terminal location. 3. During the biosynthesis of procollagen by tendon and cartilage cells a close correlation was observed between the extent of inter-chain disulphide bonding and the proportion of procollagen polypeptides having a triple-helical conformation. These processes appeared to commence in the rough endoplasmic reticulum and be completed in the smooth endoplasmic reticulum, but the rate at which they occur in cartilage cells is markedly slower than that found in tendon cells. 4. When the intracellular [14C]procollagen polypeptides present in the rough-endoplasmic-reticulum fractions of tendon and cartilage cells were analysed under non-reducing conditions on agarose/polyacrylamide composite gels, no significant pools of dimeric intermediates were detected. 5. In both cell types, inter-chain disulphide-bond formation occurred even when hydroxylation, and hence triple-helix formation, was inhibited. The presence of pro-alpha1- and pro-alpha2-components in a ratio of 2:1 in the disulphide-linked unhydroxylated procollagen isolated from tendon cells demonstrated that correct chain association occurs in the absence of hydroxylation. This observation is consistent with a model for the assembly of pro-gamma112-chains in which the recognition and selection of pro-alpha1-and pro-alpha2-chains in a 2:1 ratio are directed by the non-helical C-terminal extension peptides of tendon procollagen. 相似文献
10.
Studies on the biosynthesis, assembly and secretion of vitellogenin, an oestrogen-induced multicomponent protein. 总被引:1,自引:1,他引:0
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1. The process by which the egg-yolk protein precursor vitellogenin is biosynthesized, assembled and secreted by Xenopus laevis (South African clawed toad) liver was studied. It was previously shown in other laboratories that vitellogenin contains the two egg-yolk proteins lipovitellin (mol.wt. 140 000) and phosvitin (mol.wt. 35 000). 2. Evidence is presented which shows that Xenopus liver microsomal fractions synthesize precursors of vitellogenin. These precursors were solubilized from the membranes with detergent and analysed by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. This analysis indicated that there is only one precursor polypeptide, and this has mol.wt. approx. 200 000 +/- 20 000. This demonstrates that the egg-yolk proteins are translated as part of this larger polypeptide. 3. Experiments also demonstrate the existence of a microsomal proteinase which is able to cleave the precursor into smaller fragments. The nature of these fragments provided some indirect evidence that phosvitin and lipovitellin light chains are situated together within the precursor molecule. 4. These precursor data fit in well with structural studies on serum vitellogenin, since it has been shown that the latter protein consists of two identical subunits each with a mobility on sodium dodecyl sulphate/polyacrylamide gels identical with that shown by the microsomal precursor. This indicates that both the intracellular precursor and subunit of vitellogenin have similar (but not necessarily identical) molecular weights. 5. It was also shown that trypsin or chymotrypsin can cleave the serum vitellogenin into leucine- and serine-rich fragments which resemble lipovitellin and phosvitin respectively. Attention is, however, drawn to the fact that the serine-rich fragment is not identical with phosvitin, since it contains eight times more leucine than that expected for the authentic phosvitin molecule [Penning (1976) Ph.D. Thesis, University of Southampton]. 相似文献