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71.
Sacred sites lie at the core of indigenous peoples' land claims and negotiations with the state. These sites are often subject to accusations of inauthenticity by state actors, which potentially lead to the delegitimization of claims over ancestral land. This article argues that misunderstandings in Mapuche land negotiations in Chile do not originate as strategic refusals to understand, but rather in a form of understanding which aims to make radical differences commensurable within the logics of statecraft and national society. In the process of cultural translation, the ontological principles that make certain places sacred in the Mapuche lived world are not recognized, resulting in the transformation of these sites into symbols of identity strategically employed for political ends.  相似文献   
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Skeletal muscle has the ability to regenerate new muscle fibers after injury. The process of new muscle formation requires that quiescent mononuclear muscle precursor cells (myoblasts) become activated, proliferate, differentiate, and fuse into multinucleated myotubes which, in turn, undergo further differentiation and mature to form functional muscle fibers. Previous data demonstrated the crucial role played by 3-hydroxy 3-methylglutaryl coenzyme A reductase (HMGR), the rate-limiting enzyme of cholesterol biosynthetic pathway, in fetal rat myoblast (L6) differentiation. This finding, along with epidemiological studies assessing the myotoxic effect of statins, HMGR inhibitors, allowed us to speculate that HMGR could be strongly involved in skeletal muscle repair. Thus, our research was aimed at evaluating such involvement: in vitro and in vivo experiments were performed on both mouse adult satellite cell derived myoblasts (SCDM) and mouse muscles injured with cardiotoxin. Results demonstrate that HMGR inhibition by the statin Simvastatin reduces SCDM fusion index, fast MHC protein levels by 60% and slow MHC by 40%. Most importantly, HMGR inhibition delays skeletal muscle regeneration in vivo. Thus, besides complaining of myopathies, patients given Simvastatin could also undergo an impairment in muscle repair.  相似文献   
74.
AHSP inhibits cellular production of the reactive oxygen species. Reduced AHSP indicates reduced protection against oxidative stressors. Our objective was to investigate AHSP levels in recurrent miscarriage (RM). Trophoblast was collected from women of 10 weeks gestation: voluntary abortion controls (VA, n = 10); spontaneous first miscarriage with subsequent normal pregnancy (SMSN, n = 15) or with subsequent miscarriage (SMSM, n = 5); RM previously investigated (RMPS, n = 5) or not previously investigated (RM, n = 5). AHSP mRNA and protein were determined using real-time quantitative polymerase chain reaction (PCR) and Western blot, respectively. One-way ANOVA was performed to assess statistical significance (p < 0.05). ahsp mRNA levels were maximally reduced in RM and RMPS (8.0 × 10−6 ± 1.3 and 8.1 × 10−6 ± 0.7, respectively) compared with SMSN and VA (16.1 × 10−6 ± 2.3 and 26.1 × 10−6 ± 2.7, respectively). SMSM showed levels significantly reduced as well (9.0 × 10−6 ± 2.3). In RM, a reduced defense from oxidative stressors is evident at first miscarriage, identifying women at high risk for subsequent eventful pregnancy. Reduced AHSP may identify women at risk of experiencing further miscarriages. Monica Emanuelli and Monia Cecati contributed equally to this paper.  相似文献   
75.
With an ever-increasing understanding of the brain mechanisms associated with core human attributes and values, there is an increasing public interest in the results of neuroscience research and the ways in which that new knowledge will be used. Here, we present perspectives on engaging the public on these issues on an international scale, the role of the media, and prospects for the new field of neuroethics as both a focus and a driver of these efforts.  相似文献   
76.
Pre-mRNP complexes were isolated from rat liver nuclei as 40S hnRNP particles, and actin-binding proteins were collected by DNase I affinity chromatography. The bound proteins were analyzed by 2D gel electrophoresis, and the following five hnRNP A/B-type proteins were identified by tandem mass spectrometry: DBP40/CBF-A (CArG binding factor A), a minor hnRNP A2 variant and three minor hnRNP A3 (mBx) variants. DBP40 was chosen for further analysis of the association of actin with the pre-mRNP complex. It was shown in vitro that purified actin binds to recombinant DBP40 suggesting that the interaction between actin and DBP40 is direct in the pre-mRNP particles. The association of actin with DBP40 was further explored in vivo. It was shown in a transfection study that DBP40 appears both in the nucleus and cytoplasm. Microinjection experiments revealed that DBP40 is exported from the nucleus to the cytoplasm. Finally, RNA–protein and protein–protein cross-linking experiments showed that DBP40 interacts with poly(A)+ RNA as well as actin, both in the nucleus and cytoplasm. We propose that actin associated with DBP40, and perhaps with additional hnRNP A/B-type proteins, is transferred from nucleus to cytoplasm bound to mRNA.  相似文献   
77.
(6S)-Hydroxy-3-oxo-alpha-ionol glucosides from Capparis spinosa fruits   总被引:1,自引:0,他引:1  
Two new (6S)-hydroxy-3-oxo-alpha-ionol glucosides, together with corchoionoside C ((6S,9S)-roseoside) and a prenyl glucoside, were isolated from mature fruits of Capparis spinosa. The structures were established on the basis of spectroscopic, chiroptic and chemical evidence. In addition, the 13C-resonance of C-9 was found to be of particular diagnostic value in assigning the absolute configuration at that center in ionol glycosides. The alpha-ionol derivatives are metabolites of (+)-(S)-abscisic acid.  相似文献   
78.
During spermatogenesis, mRNA localization and translation are believed to be regulated in a stage-specific manner. We report here that the Protamine2 (Prm2) mRNA transits through chromatoid bodies of round spermatids and localizes to cytosol of elongating spermatids for translation. The transacting factor CBF-A, also termed Hnrnpab, contributes to temporal regulation of Prm2 translation. We found that CBF-A co-localizes with the Prm2 mRNA during spermatogenesis, directly binding to the A2RE/RTS element in the 3′ UTR. Although both p37 and p42 CBF-A isoforms interacted with RTS, they associated with translationally repressed and de-repressed Prm2 mRNA, respectively. Only p42 was found to interact with the 5′cap complex, and to co-sediment with the Prm2 mRNA in polysomes. In CBF-A knockout mice, expression of protamine 2 (PRM2) was reduced and the Prm2 mRNA was prematurely translated in a subset of elongating spermatids. Moreover, a high percentage of sperm from the CBF-A knockout mouse showed abnormal DNA morphology. We suggest that CBF-A plays an important role in spermatogenesis by regulating stage-specific translation of testicular mRNAs.  相似文献   
79.
Crohn’s disease (CD) is notably characterized by the expansion of visceral fat with small adipocytes expressing a high proportion of anti-inflammatory genes. Conversely, visceral fat depots in ulcerative colitis (UC) patients have never been characterized. Our study aims were a) to compare adipocyte morphology and gene expression profile and bacterial translocation in omental (OM) and mesenteric (MES) adipose tissue of patients with UC and CD, and b) to investigate the effect of bacterial infection on adipocyte proliferation in vitro. Specimens of OM and MES were collected from 11 UC and 11 CD patients, processed and examined by light microscopy. Gene expression profiles were evaluated in adipocytes isolated from visceral adipose tissue using microarray and RTqPCR validations. Bacteria within adipose tissue were immuno-detected by confocal scanning laser microscopy. Adipocytes were incubated with Enterococcus faecalis and cells counted after 24h. Morphology and molecular profile of OM and MES revealed that UC adipose tissue is less inflamed than CD adipose tissue. Genes linked to inflammation, bacterial response, chemotaxis and angiogenesis were down-regulated in adipocytes from UC compared to CD, whereas genes related to metallothioneins, apoptosis pathways and growth factor binding were up-regulated. A dense perinuclear positivity for Enterococcus faecalis was detected in visceral adipocytes from CD, whereas positivity was weak in UC. In vitro bacterial infection was associated with a five-fold increase in the proliferation rate of OM preadipocytes. Compared to UC, visceral adipose tissue from CD is more inflamed and more colonized by intestinal bacteria, which increase adipocyte proliferation. The influence of bacteria stored within adipocytes on the clinical course of IBD warrants further investigations.  相似文献   
80.
The need for osteocyte cultures is well known to the community of bone researchers; isolation of primary osteocytes is difficult and produces low cell numbers. Therefore, the most widely used cellular system is the osteocyte-like MLO-Y4 cell line.The method here described refers to the use of retinoic acid to generate a homogeneous population of ramified cells with morphological and molecular osteocyte features.After isolation of osteoblasts from mouse calvaria, all-trans retinoic acid (ATRA) is added to cell medium, and cell monitoring is conducted daily under an inverted microscope. First morphological changes are detectable after 2 days of treatment and differentiation is generally complete in 5 days, with progressive development of dendrites, loss of the ability to produce extracellular matrix, down-regulation of osteoblast markers and up-regulation of osteocyte-specific molecules.Daily cell monitoring is needed because of the inherent variability of primary cells, and the protocol can be adapted with minimal variation to cells obtained from different mouse strains and applied to transgenic models. The method is easy to perform and does not require special instrumentation, it is highly reproducible, and rapidly generates a mature osteocyte population in complete absence of extracellular matrix, allowing the use of these cells for unlimited biological applications.  相似文献   
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