896 resultados para Post-convertibility accumulation model
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Kosrae is the most remote island of the Federated States of Micronesia (FSM), with a population of less than 7,000 inhabitants, located in the Pacific Ocean between Hawaii and Guam. FSM is an independent sovereign nation consisting of four states in total: Pohnpei, Chuuk, Yap, and Kosrae. Having passed through the hands of Spain, Germany and Japan, the United States gained administrative control of FSM after WWII, as commissioned by the UN. The FSM became an independent nation in 1986 while still retaining affiliation with the US under a ‘Compact of Free Association’. Now both Kosraean and English are considered to be the two official languages and the variety of Kosraean English which has arisen proves for an interesting comparative study. In order to obtain the relevant data, I spent three months on the island of Kosrae, interviewing 90 local speakers, ranging in age (16-70), occupation, sex and time spent off island. The 45 minute long interviews were informal but supported by participant information to capture relevant data and conversations were guided in a way that aimed to reveal language and cultural attitudes. With reference to these samples, I examine the effects of American English on the language use in Kosrae. This paper aims to present a broad analysis of phonological, morphosyntactic and pragmatic features, such as pro-dropping, discourse markers and other practices in order to demonstrate the similarities and differences between the two varieties, which are coming to shape the variety developing on Kosrae. Having transcribed conversations using the tool Elan, I will put particular focus on [h] deletion and insertion, a rare occurrence found in a variety of post-colonial American English which I believe is of particular interest. I assess the presence of English in Kosrae with reference to sociological influences, past and present. First, I discuss the extralinguistic factors which have shaped the English that is currently used on Kosrae, including migration between US and FSM, and English as a language of administration, social media usage and visual media presence. Secondly, I assess the use of English in this community in light of Schneider’s (2007) ‘Dynamic Model’, with reference to America’s contribution as an ‘exploitation colony’ as defined by Mufwene (2001). Finally, an overview of the salient linguistic characteristics of Kosraean English, based on the data collected will be presented and compared to features associated with standard American English in view of examining overlap and divergence. The overall objective is to present a cross-linguistic description of a hitherto unexamined English emerging in a postcolonial environment with a juxtaposed contact variety. Mufwene, Salikoko S. 2001. The ecology of language evolution. Cambridge: Cambridge University Press. Schneider, E. (2007). Postcolonial Englishes. Cambridge: Cambridge University Press. Segal, H.G. (1989) Kosrae, The Sleeping Lady Awakens. Kosrae: Kosrae Tourist Division, Dept. Of Conservation and Development. Keywords: American English, Global English, Pacific English, Morphosyntactic, Phonological, Variation, Discourse
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Domestic dog rabies is an endemic disease in large parts of the developing world and also epidemic in previously free regions. For example, it continues to spread in eastern Indonesia and currently threatens adjacent rabies-free regions with high densities of free-roaming dogs, including remote northern Australia. Mathematical and simulation disease models are useful tools to provide insights on the most effective control strategies and to inform policy decisions. Existing rabies models typically focus on long-term control programs in endemic countries. However, simulation models describing the dog rabies incursion scenario in regions where rabies is still exotic are lacking. We here describe such a stochastic, spatially explicit rabies simulation model that is based on individual dog information collected in two remote regions in northern Australia. Illustrative simulations produced plausible results with epidemic characteristics expected for rabies outbreaks in disease free regions (mean R0 1.7, epidemic peak 97 days post-incursion, vaccination as the most effective response strategy). Systematic sensitivity analysis identified that model outcomes were most sensitive to seven of the 30 model parameters tested. This model is suitable for exploring rabies spread and control before an incursion in populations of largely free-roaming dogs that live close together with their owners. It can be used for ad-hoc contingency or response planning prior to and shortly after incursion of dog rabies in previously free regions. One challenge that remains is model parameterisation, particularly how dogs' roaming and contacts and biting behaviours change following a rabies incursion in a previously rabies free population.
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BACKGROUND The noble gas xenon is considered as a neuroprotective agent, but availability of the gas is limited. Studies on neuroprotection with the abundant noble gases helium and argon demonstrated mixed results, and data regarding neuroprotection after cardiac arrest are scant. We tested the hypothesis that administration of 50% helium or 50% argon for 24 h after resuscitation from cardiac arrest improves clinical and histological outcome in our 8 min rat cardiac arrest model. METHODS Forty animals had cardiac arrest induced with intravenous potassium/esmolol and were randomized to post-resuscitation ventilation with either helium/oxygen, argon/oxygen or air/oxygen for 24 h. Eight additional animals without cardiac arrest served as reference, these animals were not randomized and not included into the statistical analysis. Primary outcome was assessment of neuronal damage in histology of the region I of hippocampus proper (CA1) from those animals surviving until day 5. Secondary outcome was evaluation of neurobehavior by daily testing of a Neurodeficit Score (NDS), the Tape Removal Test (TRT), a simple vertical pole test (VPT) and the Open Field Test (OFT). Because of the non-parametric distribution of the data, the histological assessments were compared with the Kruskal-Wallis test. Treatment effect in repeated measured assessments was estimated with a linear regression with clustered robust standard errors (SE), where normality is less important. RESULTS Twenty-nine out of 40 rats survived until day 5 with significant initial deficits in neurobehavioral, but rapid improvement within all groups randomized to cardiac arrest. There were no statistical significant differences between groups neither in the histological nor in neurobehavioral assessment. CONCLUSIONS The replacement of air with either helium or argon in a 50:50 air/oxygen mixture for 24 h did not improve histological or clinical outcome in rats subjected to 8 min of cardiac arrest.
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Gut was studied as a prototypical mucosal membrane in the murine BDF-1 syngeneic bone marrow transplant model. Measures of jejunal intraepithelial lymphocytes (IELs) and crypt cells were obtained by standard techniques and a method of quantifying gut lamina propria plasma cells (PCs) was developed. The degree of ablation of gut PCs and IELs after 900 rads total body irradiation with ('60)Co, and their repopulation effected by transplantation with 2.0 x 10('5) or 1.0 x 10('6) bone marrow cells demonstrated a prolonged period of profound depression in population levels of these cells which was not reflected by the extent of damage sustained to the epithelium. Differences in the depopulation and recovery of gut PCs and IELs revealed a tendency towards initial differentiation of effector cells. A positive dose response to high bone marrow cell innocula was obtained. Subsequent studies determined that gut IEL and PC repopulation was potentiated by the addition of IELs or buffy coat cells (BCs) to the bone marrow transplant. A method of isolating 1.4 - 4.0 x 10('7) viable IELs per gram of murine small bowel was devised employing intralumenal hyaluronidase digestion of the epithelial layer and centrifugation of the resulting suspension through discontinuous Percoll gradients. Irradiated mice received 2.0 x 10('5) bone marrow cells along with an equal number of IELs or BCs. The extent and duration of depression of numbers of IELs and PCs was markedly reduced by the addition of the IEL isolate to the transplantation innocula, and to a lesser degree by the addition of BCs. The augmentation of repopuation far exceeded that expected by simple lodging of cells suggesting that the additionally transplanted cells contained a subpopulation of mucosal membrane lymphoid stem cells or helper cells. Correlation analysis of PC versus IEL levels suggests a possible feedback mechanism governing the relative size of their populations. Normal ratios of IgA, IgM, and IgG bearing PCs was maintained post transplantation with all of the regimens. ^
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miRNAs function to regulate gene expression through post-transcriptional mechanisms to potentially regulate multiple aspects of physiology and development. Whole transcriptome analysis has been conducted on the citron kinase mutant rat, a mutant that shows decreases in brain growth and development. The resulting differences in RNA between mutant and wild-type controls can be used to identify genetic pathways that may be regulated differentially in normal compared to abnormal neurogenesis. The goal of this thesis was to verify, with quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), changes in miRNA expression in Cit-k mutants and wild types. In addition to confirming miRNA expression changes, bio-informatics software TargetScan 5.1 was used to identify potential mRNA targets of the differentially expressed miRNAs. The miRNAs that were confirmed to change include: rno-miR-466c, mmu-miR-493, mmu-miR-297a, hsa-miR-765, and hsa-miR-1270. The TargetScan analysis revealed 347 potential targets which have known roles in development. A subset of these potential targets include genes involved in the Wnt signaling pathway which is known to be an important regulator of stem cell development.
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Credit markets with asymmetric information often prefer credit rationing as a profit maximizing device. This paper asks whether the presence of informal credit markets reduces the cost of credit rationing, that is, whether it can alleviate the impact of asymmetric information based on the available information. We used a dynamic general equilibrium model with heterogenous agents to assess this. Using Indian credit market data our study shows that the presence of informal credit market can reduce the cost of credit rationing by separating high risk firms from the low risk firms in the informal market. But even after this improvement, the steady state capital accumulation is still much lower as compared to incentive based market clearing rates. Through self revelation of each firm's type, based on the incentive mechanism, banks can diversify their risk by achieving a separating equilibrium in the loan market. The incentive mechanism helps banks to increase capital accumulation in the long run by charging lower rates and lending relatively higher amount to the less risky firms. Another important finding of this study is that self-revelation leads to very significant welfare improvement, as measured by consumptiuon equivalence.
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Though E2F1 is deregulated in most human cancers by mutations of the p16-cyclin D-Rb pathway, it also exhibits tumor suppressive activity. A transgenic mouse model overexpressing E2F1 under the control of the bovine keratin 5 (K5) promoter exhibits epidermal hyperplasia and spontaneously develops tumors in the skin and other epithelial tissues after one year of age. In a p53-deficient background, aberrant apoptosis in K5 E2F1 transgenic epidermis is reduced and tumorigenesis is accelerated. In sharp contrast, K5 E2F1 transgenic mice are resistant to papilloma formation in the DMBA/TPA two-stage carcinogenesis protocol. K5 E2F4 and K5 DP1 transgenic mice were also characterized and both display epidermal hyperplasia but do not develop spontaneous tumors even in cooperation with p53 deficiency. These transgenic mice do not have increased levels of apoptosis in their skin and are more susceptible to papilloma formation in the two-stage carcinogenesis model. These studies show that deregulated proliferation does not necessarily lead to tumor formation and that the ability to suppress skin carcinogenesis is unique to E2F1. E2F1 can also suppress skin carcinogenesis when okadaic acid is used as the tumor promoter and when a pre-initiated mouse model is used, demonstrating that E2F1's tumor suppressive activity is not specific for TPA and occurs at the promotion stage. E2F1 was thought to induce p53-dependent apoptosis through upregulation of p19ARF tumor suppressor, which inhibits mdm2-mediated p53 degradation. Consistent with in vitro studies, the overexpression of E2F1 in mouse skin results in the transcriptional activation of the p19ARF and the accumulation of p53. Inactivation of either p19ARF or p53 restores the sensitivity of K5 E2F1 transgenic mice to DMBA/TPA carcinogenesis, demonstrating that an intact p19ARF-p53 pathway is necessary for E2F1 to suppress carcinogenesis. Surprisingly, while p53 is required for E2F1 to induce apoptosis in mouse skin, p19ARF is not, and inactivation of p19ARF actually enhances E2F1-induced apoptosis and proliferation in transgenic epidermis. This indicates that ARF is important for E2F1-induced tumor suppression but not apoptosis. Senescence is another potential mechanism of tumor suppression that involves p53 and p19ARF. K5 E2F1 transgenic mice initiated with DMBA and treated with TPA show an increased number of senescence cells in their epidermis. These experiments demonstrate that E2F1's unique tumor suppressive activity in two-stage skin carcinogenesis can be genetically separated from E2F1-induced apoptosis and suggest that senescence utilizing the p19ARF-p53 pathway plays a role in tumor suppression by E2F1. ^
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This thesis explores how LGBT marriage activists and lawyers have employed a racial interpretation of due process and equal protection in recent same-sex marriage litigation. Special attention is paid to the Supreme Court's opinion in Loving v. Virginia, the landmark case that declared anti-miscegenation laws unconstitutional. By exploring the use of racial precedent in same-sex marriage litigation and its treatment in state court cases, this thesis critiques the racial interpretation of due process and equal protection that became the basis for LGBT marriage briefs and litigation, and attempts to answer the question of whether a racial interpretation of due process and equal protection is an appropriate model for same-sex marriage litigation both constitutionally and strategically. The existing scholarly literature fails to explore how this issue has been treated in case briefs, which are very important elements in any legal proceeding. I will argue that through an analysis of recent state court briefs in Massachusetts and Connecticut, Loving acts as logical precedent for the legalization of same-sex marriage. I also find, more significantly, that although this racial interpretation of due process and equal protection represented by Loving can be seen as an appropriate model for same-sex marriage litigation constitutionally, questions remain about its strategic effectiveness, as LGBT lawyers have moved away from race in some arguments in these briefs. Indeed, a racial interpretation of Due Process and Equal Protection doctrine imposes certain limits on same-sex marriage litigation, of which we are warned by some Critical Race theorists, Latino Critical Legal theorists, and other scholars. In order to fully incorporate a discussion of race into the argument for legalizing same-sex marriage, the dangers posed by the black/white binary of race relations must first be overcome.
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This table accompanies the manuscript entitled "Religion/Spirituality and Change in Meaning after Bereavement: Qualitative Evidence for the Meaning Making Model" by Wortmann & Park (2009). The table summarizes the sample characteristics for published, qualitative studies that describe the involvement of religion/spirituality in adjustment after bereavement. Fields include author(s)'s last name, publication year, population characteristics and sample size, study design, age of the bereaved, type or cause of death, and time post-loss.
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We develop a portfolio balance model with real capital accumulation. The introduction of real capital as an asset as well as a good produced and demanded by firms enriches extant portfolio balance models of exchange rate determination. We show that expansionary monetary policy causes exchange rate overshooting, not once, but twice; the secondary repercussion comes through the reaction of firms to changed asset prices and the firms' decisions to invest in real capital. The model sheds further light on the volatility of real and nominal exchange rates, and it suggests that changes in corporate sector profitability may affect exchange rates through portfolio diversification in corporate securities.
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Numerous animal models have been used to study diet effects on cholesterol and lipoprotein metabolism. However, most of those models differ from humans in the plasma distribution of cholesterol and in the processing of lipoproteins in the plasma compartment. Although transgenic or knock-out mice have been used to study a specific pathway involved in cholesterol metabolism, these data are of limited use because other metabolic pathways and responses to interventions may differ from the human condition.Carbohydrate restricted diets have been shown to reduce plasma triglycerides, increase HDL cholesterol and promote the formation of larger, less atherogenic LDL. However, the mechanisms behind these responses and the relation to atherosclerotic events in the aorta have not been explored in detail due to the lack of an appropriate animal model. Guinea pigs carry the majority of the cholesterol in LDL and possess cholesterol ester transfer protein and lipoprotein lipase activities, which results in reverse cholesterol transport and delipidation cascades equivalent to the human situation. Further, carbohydrate restriction has been shown to alter the distribution of LDL subfractions, to decrease cholesterol accumulation in aortas and to decrease aortic cytokine expression. It is the purpose of this review to discuss the use of guinea pigs as useful models to evaluate diet effects on lipoprotein metabolism, atherosclerosis and inflammation with an emphasis on carbohydrate restricted diets.
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With substance abuse treatment expanding in prisons and jails, understanding how behavior change interacts with a restricted setting becomes more essential. The Transtheoretical Model (TTM) has been used to understand intentional behavior change in unrestricted settings, however, evidence indicates restrictive settings can affect the measurement and structure of the TTM constructs. The present study examined data from problem drinkers at baseline and end-of-treatment from three studies: (1) Project CARE (n = 187) recruited inmates from a large county jail; (2) Project Check-In (n = 116) recruited inmates from a state prison; (3) Project MATCH, a large multi-site alcohol study had two recruitment arms, aftercare (n = 724 pre-treatment and 650 post-treatment) and outpatient (n = 912 pre-treatment and 844 post-treatment). The analyses were conducted using cross-sectional data to test for non-invariance of measures of the TTM constructs: readiness, confidence, temptation, and processes of change (Structural Equation Modeling, SEM) across restricted and unrestricted settings. Two restricted (jail and aftercare) and one unrestricted group (outpatient) entering treatment and one restricted (prison) and two unrestricted groups (aftercare and outpatient) at end-of-treatment were contrasted. In addition TTM end-of-treatment profiles were tested as predictors of 12 month drinking outcomes (Profile Analysis). Although SEM did not indicate structural differences in the overall TTM construct model across setting types, there were factor structure differences on the confidence and temptation constructs at pre-treatment and in the factor structure of the behavioral processes at the end-of-treatment. For pre-treatment temptation and confidence, differences were found in the social situations factor loadings and in the variance for the confidence and temptation latent factors. For the end-of-treatment behavioral processes, differences across the restricted and unrestricted settings were identified in the counter-conditioning and stimulus control factor loadings. The TTM end-of-treatment profiles were not predictive of drinking outcomes in the prison sample. Both pre and post-treatment differences in structure across setting types involved constructs operationalized with behaviors that are limited for those in restricted settings. These studies suggest the TTM is a viable model for explicating addictive behavior change in restricted settings but calls for modification of subscale items that refer to specific behaviors and caution in interpreting the mean differences across setting types for problem drinkers. ^
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Plasma low-density lipoprotein (LDL) levels are positively correlated with the incidence of coronary artery disease. In the circulation, the plasma LDL clearance is mainly achieved by the uptake via LDL receptor (LDLR). Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a newly discovered gene, playing an important role in LDL metabolism. Gain-of-function mutations of PCSK9 lead to hypercholesterolemia and loss-of-function mutations of PCSK9 are associated with decrease of LDL cholesterol. The effects of PCSK9 on cholesterol levels are the consequence of a strong interaction between the catalytic domain of PCSK9 and epidermal growth factor-like repeat A (EGF-A) domain of LDLR on the cell surface of hepatocytes. This PCSK9/LDLR complex enters the cell via endocytosis, where both PCSK9 and LDLR are removed via the lysosome pathway, resulting in decreased levels of LDLR and accumulation of LDL in the plasma. However, whether this is the exclusive function of PCSK9 on LDL metabolism was challenged by us; we observed PCSK9 interacted with apolipoprotein B (apoB) and increased apoB production, irrespective of the LDLR. ApoB is the primary structure protein of LDL particle and it also serves as the ligand for the LDL receptor. There is ample evidence showing that the levels of apoB are a better indicator for heart disease than either total cholesterol or LDL cholesterol levels. We used a second-generation adenoviral vector to overexpress PCSK9 (Ad-PCSK9) in wild-type C57BL/6 and LDLR deficient mice (Ldlr-/- and Ldlr-/-Apobec1-/-). Our study revealed that overexpression of PCSK9 promoted the production and secretion of apoB in the form of very-low density lipoprotein (VLDL), which is the precursor of LDL, in the 3 mouse models studied (C57BL/6J, Ldlr-/-, and Ldlr-/-Apobec1-/-). The increased apoB production in mice was regulated at post-transcriptional levels, since there was no difference in apoB mRNA levels between mice treated with Ad-PCSK9 and control vector Ad-Null. By using pulse-chase experiment on primary hepatocytes, we showed that overexpression of PCSK9 increased the secretion of apoB, independent of LDLR. In the circulation, we showed that PCSK9 was associated with LDL particles. By using 3 different protein–protein interaction assays of co-immunoprecipitation, mammalian two-hybrid system, and in situ proximity ligation assay, we demonstrated a direct protein–protein interaction between PCSK9 and apoB. The impact of this interaction inhibited the physiological removal process of apoB via autophagosome/lysosome pathway in an LDLR-independent fashion, resulting in increased production and secretion of apoB-containing lipoproteins. The significance of this process was shown in the Pcsk9 knockout mice in the background of Ldlr-/-Apobec1-/- mice (triple knockout mice); in the absence of Pcsk9 (triple knockout mice) the levels of cholesterol, triacylglycerol, and apoB decreased significantly in comparison to that of Ldlr-/-Apobec1-/- mice. Taken together, our study demonstrated a direct intracellular interaction of PCSK9 with apoB, resulting in the inhibition of apoB degradation via the autophagosome/lysosome pathway independent of LDLR. This discovery provides a new concept of the importance of PCSK9 and suggests new approaches for the therapeutic intervention of hyperlipidemia.
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Objective. Weight gain after cancer treatment is associated with breast cancer recurrence. In order to prolong cancer-free survivorship, interventions to manage post-diagnosis weight are sometimes conducted. However, little is known about what factors are associated with weight management behaviors among cancer survivors. In this study, we examined associations of demographic, clinical, and psychosocial variables with weight management behaviors in female breast cancer survivors. We also examined whether knowledge about post-diagnosis weight gain and its risk is associated with weight management behaviors. ^ Methods. 251 female breast cancer survivors completed an internet survey. They reported current performance of three weight management behaviors (general weight management, physical activity, and healthy diet). We also measured attitude, elf-efficacy, knowledge and social support regarding these behaviors along with demographic and clinical characteristics. ^ Results. Multiple regression models for the weight management behaviors explained 17% of the variance in general weight management, 45% in physical activity and 34% in healthy dieting. The models had 9–14 predictor variables which differed in each model. The variables associated with all three behaviors were social support and self-efficacy. Self-efficacy showed the strongest contribution in all models. The knowledge about weight gain and its risks was not associated with any weight management behaviors. However, women who obtained the knowledge during cancer treatment were more likely to engage in physical activity and healthy dieting. ^ Conclusions. The findings suggest that an intervention designed to increase their self-efficacy to manage weight, to be physically active, to eat healthy will effectively promote survivors to engage in these behaviors. Knowledge may motivate women to manage post-diagnosis weight about risk if information is provided during cancer treatment.^
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Tumor Suppressor Candidate 2 (TUSC2) is a novel tumor suppressor gene located in the human chromosome 3p21.3 region. TUSC2 mRNA transcripts could be detected on Northern blots in both normal lung and some lung cancer cell lines, but no endogenous TUSC2 protein could be detected in a majority of lung cancer cell lines. Mechanisms regulating TUSC2 protein expression and its inactivation in primary lung cancer cells are largely unknown. We investigated the role of the 5’- and 3’-untranslated regions (UTRs) of the TUSC2 gene in the regulation of TUSC2 protein expression. We found that two small upstream open-reading frames (uORFs) in the 5’UTR of TUSC2 could markedly inhibit the translational initiation of TUSC2 protein by interfering with the “scanning” of the ribosome initiation complexes. Site-specific stem-loop array reverse transcription-polymerase chain reaction (SLA-RT-PCR) verified several micoRNAs (miRNAs) targeted at 3’UTR and directed TUSC2 cleavage and degradation. In addition, we used the established let-7-targeted high mobility group A2 (Hmga2) mRNA as a model system to study the mechanism of regulation of target mRNA by miRNAs in mammalian cells under physiological conditions. There have been no evidence of direct link between mRNA downregulation and mRNA cleavages mediated by miRNAs. Here we showed that the endonucleolytic cleavages on mRNAs were initiated by mammalian miRNA in seed pairing style. Let-7 directed cleavage activities among the eight predicted potential target sites have varied efficiency, which are influenced by the positional and the structural contexts in the UTR. The 5’ cleaved RNA fragments were mostly oligouridylated at their 3’-termini and accumulated for delayed 5’–3’ degradation. RNA fragment oligouridylation played important roles in marking RNA fragments for delayed bulk degradation and in converting RNA degradation mode from 3’–5’ to 5’–3’ with cooperative efforts from both endonucleolytic and non-catalytic miRNA-induced silencing complex (miRISC). Our findings point to a mammalian miRNA-mediated mechanism for the regulation of mRNA that miRNA can decrease target mRNA through target mRNA cleavage and uridine addition