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961.
Loïc Wacquant 《Dialectical Anthropology》2010,34(4):605-620
The carceral boom in post-Civil Rights America results not from profit-seeking but from state-crafting. Accordingly, we must slay the chimera of the “Prison Industrial Complex” and forsake its derived tale of the “Prisoner Reentry Industry.” This murky economic metaphor is doubly misleading: first, most released convicts experience not reentry but ongoing circulation between the prison and their dispossessed neighborhoods; second, the institutions entrusted with supervising them are not market operators but elements of the bureaucratic field as characterized by Pierre Bourdieu. Post-custodial supervision is a ceremonial component of “prisonfare,” which complements “workfare” through organizational isomorphism, and partakes of the neoliberal reengineering of the state. Reentry outfits are not an antidote to but an extension of punitive containment as government technique for managing problem categories and territories in the dualizing city. To capture the glaring economic irrationality and bureaucratic absurdities of the oversight of felons behind as well as beyond bars, our theoretical inspiration should come not from the radical critique of capitalism but from the neo-Durkheimian sociology of organization and the neo-Weberian theory of the state as a classifying and stratifying agency. 相似文献
962.
Eberhard Schneider Galyna Pliushch Nady El Hajj Danuta Galetzka Alexander Puhl Martin Schorsch Katrin Frauenknecht Thomas Riepert Achim Tresch Annette M. Müller Wiltrud Coerdt Ulrich Zechner Thomas Haaf 《Nucleic acids research》2010,38(12):3880-3890
DNA methylation is an epigenetic modification that plays an important role in gene regulation. It can be influenced by stochastic events, environmental factors and developmental programs. However, little is known about the natural variation of gene-specific methylation patterns. In this study, we performed quantitative methylation analyses of six differentially methylated imprinted genes (H19, MEG3, LIT1, NESP55, PEG3 and SNRPN), one hypermethylated pluripotency gene (OCT4) and one hypomethylated tumor suppressor gene (APC) in chorionic villus, fetal and adult cortex, and adult blood samples. Both average methylation level and range of methylation variation depended on the gene locus, tissue type and/or developmental stage. We found considerable variability of functionally important methylation patterns among unrelated healthy individuals and a trend toward more similar methylation levels in monozygotic twins than in dizygotic twins. Imprinted genes showed relatively little methylation changes associated with aging in individuals who are >25 years. The relative differences in methylation among neighboring CpGs in the generally hypomethylated APC promoter may not only reflect stochastic fluctuations but also depend on the tissue type. Our results are consistent with the view that most methylation variation may arise after fertilization, leading to epigenetic mosaicism. 相似文献
963.
Fran?ois Roudier Lionel Gissot Frédéric Beaudoin Richard Haslam Louise Michaelson Jessica Marion Diana Molino Amparo Lima Liên Bach Halima Morin Frédérique Tellier Jean-Christophe Palauqui Yannick Bellec Charlotte Renne Martine Miquel Marco DaCosta Julien Vignard Christine Rochat Jonathan E. Markham Patrick Moreau Johnathan Napier Jean-Denis Faure 《The Plant cell》2010,22(2):364-375
Very-long-chain fatty acids (VLCFAs) are essential for many aspects of plant development and necessary for the synthesis of seed storage triacylglycerols, epicuticular waxes, and sphingolipids. Identification of the acetyl-CoA carboxylase PASTICCINO3 and the 3-hydroxy acyl-CoA dehydratase PASTICCINO2 revealed that VLCFAs are important for cell proliferation and tissue patterning. Here, we show that the immunophilin PASTICCINO1 (PAS1) is also required for VLCFA synthesis. Impairment of PAS1 function results in reduction of VLCFA levels that particularly affects the composition of sphingolipids, known to be important for cell polarity in animals. Moreover, PAS1 associates with several enzymes of the VLCFA elongase complex in the endoplasmic reticulum. The pas1 mutants are deficient in lateral root formation and are characterized by an abnormal patterning of the embryo apex, which leads to defective cotyledon organogenesis. Our data indicate that in both tissues, defective organogenesis is associated with the mistargeting of the auxin efflux carrier PIN FORMED1 in specific cells, resulting in local alteration of polar auxin distribution. Furthermore, we show that exogenous VLCFAs rescue lateral root organogenesis and polar auxin distribution, indicating their direct involvement in these processes. Based on these data, we propose that PAS1 acts as a molecular scaffold for the fatty acid elongase complex in the endoplasmic reticulum and that the resulting VLCFAs are required for polar auxin transport and tissue patterning during plant development. 相似文献
964.
Abdeslem El Idrissi Xin Yan Francoise Sidime William L’Amoreaux 《Journal of biomedical science》2010,17(Z1):S8
Background
The fragile X mouse model shows an increase in seizure susceptibility, indicating an involvement of the GABAergic system via an alteration in cellular excitability. In the brain, we have previously described a reduction in GABAA receptor expression as a likely basis for this susceptibility. In the brains of fragile X mice, this reduction in receptor expression culminates with a concomitant increase in the expression of glutamic acid decarboxylase (GAD), the enzyme responsible for GABA synthesis. Further, voltage-sensitive calcium channel expression is reduced in the pancreas of the fragile X mouse. Since there are considerable similarities in the GABAergic system in the brain and pancreas, we evaluated the protective role of taurine in pancreatic islet development in both wild type (WT) and fragile X mice (KO).Methods
One-month-old FVB/NJ males or age-matched fmr1-knockout (KO) mice were supplemented with taurine in drinking water (0.05% w/v) for four weeks. Age-matched controls were fed water only for the same duration. At four weeks, mice were sacrificed and pancreases processed for histology and immunohistochemical studies on changes of insulin, glucagon and somatostatin expression. Additional mice were subjected to a glucose tolerance test.Results
Taurine treatment resulted in a significant increase in the number and size of islets. WT taurine-fed mice, slightly hypoglycemic prior to glucose injection, showed significantly reduced plasma glucose at 30 min post-injection when compared to control mice. KO mice had normal baseline plasma glucose concentration; however, following glucose injection they had higher plasma glucose levels at 30 min when compared to controls. Supplementation of taurine to KO mice resulted in reduced baseline levels of plasma glucose. After glucose injection, the taurine-fed KO mice had reduced plasma glucose at 30 min compared to KO. Concomitant with the increased islets size and glucose tolerance observed in taurine-fed mice there was an increase in insulin, glucagon and somatostatin immunoreactivity in the islets of WT mice. In the KO mice however, insulin levels were not affected whereas glucagon and somatostatin levels were reduced. Exocytosis of these hormones is calcium-dependent, therefore any exacerbation of calcium homeostasis could affect hormone release. We found the expression of the voltage sensitive calcium channels (VSCC) is drastically reduced in the pancreas of fragile X mice.Conclusions
During early development, the VSCC play an important role in calcium-dependent gene expression. Since these channels are also involved in depolarization and calcium-mediated vesicular release of neurotransmitters and pancreatic hormones, alterations in the expression of VSCC not only will affect calcium-mediated gene expression but also hormonal and neurotransmitter release creating therefore a neuroendocrine perturbation in the fragile X that may potentially affect other organ systems. We find that in the fragile X mouse, taurine treatment may partially restore functionality of the neuro-endocrine pancreas.965.
Blood screening by NAT for major transfusion transmitted viral infections (TTIs) was originally intended to complement serology for detection of infected donations. Reports from developed countries showed limited marginal value to NAT blood screening in improving blood safety. Reports on NAT results from Europe indicated yield of 1:0.6 million donations for HBV, <1:M for HCV and HIV-1-related to low prevalence of TTI. In contrast, prevalence of TTI in resource-limited countries is almost always high. As a result, more incident cases can be expected among first-time blood donors. Most reports of NAT blood donation screening in these countries showed NAT confirmed yield as high as 1/2800 for HBV and 1/3100 blood donations for HCV as reported from Thailand and Egypt, respectively. The issues for low resource countries are mostly the high cost of NAT but also the requirements of staff qualification, adequate facilities, reagent procurement and maintenance of delicate equipment. Alternatives to commercial NAT are the use of combos antigen-antibody for HIV and HCV, anti-HBc for HBV and in-house NAT. Most of these alternatives have been reported but very few comparisons are available. Once yield data is available, models for estimation of feasibility and cost-effectiveness are proposed to help decision-making. 相似文献
966.
967.
Yves‐Marie Coïc Charlotte Le Lan Jean‐Michel Neumann Nadège Jamin Françoise Baleux 《Journal of peptide science》2010,16(2):98-104
This work contributes to highlight the benefits of pseudoproline dipeptides introduction in difficult SPPS. We show how a slight modification in the positioning choice conditioned the synthesis achievement of a 54 amino acid long caveolin‐1 peptide encompassing the intramembrane domain. Furthermore, we report a side reaction correlated with the coupling steps and generating truncated fragments with a mass deviation of + 42 Da. Considering the need of structural data for membrane proteins, most of which are considered as prevalent therapeutic targets, chemical synthesis provides an interesting alternative pathway to obtain hydrophobic domains by pushing back the frontiers of conventional RP methods of purification. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
968.
Cytotoxicity and genotoxicity induced by aflatoxin B1, ochratoxin A,and their combination in cultured Vero cells 总被引:1,自引:0,他引:1
Emna El Golli‐Bennour Bochra Kouidhi Amel Bouslimi Salwa Abid‐Essefi Wafa Hassen Hassen Bacha 《Journal of biochemical and molecular toxicology》2010,24(1):42-50
Aflatoxin B1 (AFB1) and ochratoxin A (OTA) are important food‐borne mycotoxins that have been implicated in human health. In this study, independent and combinative toxicities of AFB1 and OTA were tested in cultured monkey kidney Vero cells. The experiments reported here were conducted to evaluate the effect of these toxins on cell viability followed by the determination of cell death pathways, using the quantification of DNA fragmentation and the expression of p53 and bcl‐2 protein levels. Our results showed that AFB1 and OTA caused a marked decrease of cell viability in a dose‐dependent manner. Under the same conditions, these mycotoxins increased fragmented DNA levels. In addition, p53 was activated in response to DNA damage and the expression of the antiapoptotic factor bcl‐2 decreased significantly. According to these data, AFB1 and OTA seemed to be involved in an apoptotic process. Moreover, combined AFB1 and OTA induced all the toxicities observed with the mycotoxins separately. Therefore, this combination was classified as an additive response of the two mycotoxins. © 2010 Wiley Periodicals, Inc. J Biochem Mol Toxicol 24:42–50, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20310 相似文献
969.
970.
Loïc Lesobre Frédéric Lacroix Eric Le Nuz Yves Hingrat Toni Chalah Michel Saint Jaime 《Journal of avian biology》2010,41(2):117-127
Behavioural studies have led to the perception that lekking species experience a high male reproductive skew as a consequence of females’ selective mate choice. In addition, observations suggest that females copulate only once and therefore polyandry seems unlikely as females are supposed to choose the best male available. In order to analyse the mating strategy of the Houbara bustard, an endangered lekking species under reinforcement in eastern Morocco, we used microsatellite data to perform paternity analyses. None of our observations followed common expectations under a lek mating system: we found no male reproductive skew suggesting no apparent selective female mate choice and no apparent male benefit from lekking. In contrast, a high level of polyandry (60 % of the nests) was recorded suggesting that sperm competition may operate. In addition, we present another case of conspecific brood parasitism in a lekking species and this was an unexpected alternative strategy for a species presenting high parental cost and low fecundity. The increasing number of studies contradicting common assumptions on lekking species suggests that alternative breeding strategies such as males pursuing an off‐lek mating strategy, female polyandry and even conspecific brood parasitism might be more widespread in lekking species than previously thought. 相似文献