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1.
Proc Natl Acad Sci U S A ; 120(23): e2215572120, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37252958

RESUMO

Does competition affect moral behavior? This fundamental question has been debated among leading scholars for centuries, and more recently, it has been tested in experimental studies yielding a body of rather inconclusive empirical evidence. A potential source of ambivalent empirical results on the same hypothesis is design heterogeneity-variation in true effect sizes across various reasonable experimental research protocols. To provide further evidence on whether competition affects moral behavior and to examine whether the generalizability of a single experimental study is jeopardized by design heterogeneity, we invited independent research teams to contribute experimental designs to a crowd-sourced project. In a large-scale online data collection, 18,123 experimental participants were randomly allocated to 45 randomly selected experimental designs out of 95 submitted designs. We find a small adverse effect of competition on moral behavior in a meta-analysis of the pooled data. The crowd-sourced design of our study allows for a clean identification and estimation of the variation in effect sizes above and beyond what could be expected due to sampling variance. We find substantial design heterogeneity-estimated to be about 1.6 times as large as the average standard error of effect size estimates of the 45 research designs-indicating that the informativeness and generalizability of results based on a single experimental design are limited. Drawing strong conclusions about the underlying hypotheses in the presence of substantive design heterogeneity requires moving toward much larger data collections on various experimental designs testing the same hypothesis.

2.
Proc Natl Acad Sci U S A ; 119(41): e2205779119, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36194633

RESUMO

Peer review is a well-established cornerstone of the scientific process, yet it is not immune to biases like status bias, which we explore in this paper. Merton described this bias as prominent researchers getting disproportionately great credit for their contribution, while relatively unknown researchers get disproportionately little credit [R. K. Merton, Science 159, 56-63 (1968)]. We measured the extent of this bias in the peer-review process through a preregistered field experiment. We invited more than 3,300 researchers to review a finance research paper jointly written by a prominent author (a Nobel laureate) and by a relatively unknown author (an early career research associate), varying whether reviewers saw the prominent author's name, an anonymized version of the paper, or the less-well-known author's name. We found strong evidence for the status bias: More of the invited researchers accepted to review the paper when the prominent name was shown, and while only 23% recommended "reject" when the prominent researcher was the only author shown, 48% did so when the paper was anonymized, and 65% did when the little-known author was the only author shown. Our findings complement and extend earlier results on double-anonymized vs. single-anonymized review [R. Blank, Am. Econ. Rev. 81, 1041-1067 (1991); M. A. Ucci, F. D'Antonio, V. Berghella, Am. J. Obstet. Gynecol. MFM 4, 100645 (2022)].


Assuntos
Revisão por Pares , Redação , Humanos , Revisão da Pesquisa por Pares/métodos , Pesquisadores
3.
SN Bus Econ ; 2(11): 179, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312214

RESUMO

We study decisions on welcoming or opposing welfare migration in a laboratory setting with two societies in which one subject can migrate from the poorer to the richer society, provided a majority in the richer society votes to allow that. In each society, subjects indicate their preference for a percentage contribution to a public pool. The median of these rates sets the contributions paid by everybody; a feature that results in high contribution rates with an average of 90%. Varying the multiplier with which contributions are magnified before redistribution to society members, and thus the expected gain/loss associated with migration, we find that subjects overwhelmingly welcome migrants if they expect an economic benefit, while most participants oppose migration if they would be negatively affected by it. Regarding participants' attitudes, we find that more altruistic people are more in favor of migration than more selfish people and that center right-wing oriented subjects propose lower contribution levels than center left-wing oriented subjects. We conclude that economic motives are a crucial factor for accepting or rejecting welfare migration. Therefore, a key to promoting acceptance of new migrants is to ensure and then communicate that their net effect on growth, society, and the public purse is positive. Supplementary Information: The online version contains supplementary material available at 10.1007/s43546-022-00356-6.

4.
J Bank Financ ; 133: 106247, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34785859

RESUMO

We investigate how the experience of extreme events, such as the COVID-19 market crash, influence risk-taking behavior. To isolate changes in risk-taking from other factors, we ran controlled experiments with finance professionals in December 2019 and March 2020. We observe that their investments in the experiment were 12 percent lower in March 2020 than in December 2019, although their price expectations had not changed, and although they considered the experimental asset less risky during the crash than before. This lower perceived risk is likely due to adaptive normalization, as volatility during the shock is compared to volatility experienced in real markets (which was low in December 2019, but very high in March 2020). Lower investments during the crash can be supported by higher risk aversion, not by changes in beliefs.

5.
Exp Econ ; 23(3): 788-814, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33132745

RESUMO

When the information of many individuals is pooled, the resulting aggregate often is a good predictor of unknown quantities or facts. This aggregate predictor frequently outperforms the forecasts of experts or even the best individual forecast included in the aggregation process ("wisdom of crowds"). However, an appropriate aggregation mechanism is considered crucial to reaping the benefits of a "wise crowd". Of the many possible ways to aggregate individual forecasts, we compare (uncensored and censored) arithmetic and geometric mean and median, continuous double auction market prices and sealed bid-offer call market prices in a controlled experiment. We use an asymmetric information structure, where participants know different sub-sets of the total information needed to exactly calculate the asset value to be estimated. We find that prices from continuous double auction markets clearly outperform all alternative approaches for aggregating dispersed information and that information lets only the best-informed participants generate excess returns.

6.
Arch Orthop Trauma Surg ; 140(10): 1465-1474, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32504178

RESUMO

INTRODUCTION: The use of quadriceps tendon-patellar bone (QTB) autograft for anterior cruciate ligament (ACL) reconstruction is gaining momentum. Yet, long-term results that compare this procedure with established methods are lacking. The aim of this study was to report and compare long-term results of ACL reconstruction using QTB autografts versus bone-patellar tendon-bone (BPTB) autografts, both anchored using a hardware-free press-fit fixation technique. MATERIALS AND METHODS: 60 athletes (Tegner score ≥6) with primary ACL rupture were prospectively randomized into two groups. 56 patients were evaluated after a mean duration of 12.2 ± 1.9 months (range 10-14) and 43 patients after 10.3 ± 0.2 years (range 10-11). RESULTS: On final follow-up, 90% of patients scored very good and good results in the functional Lysholm score (mean 99 ± 7.1, range 74-100 points). Normal or almost normal IKDC score was reported by 84% of the patients (mean 97 ± 9.5, range 60-100 points). The activity level decreased in the Tegner score from median of 7 before injury to 6 after 10 years. The KT-1000 arthrometer showed a difference in the anterior translation of less than 3 mm (mean 1.0 ± 1.2, range - 1 to 5 mm) in 91% of the patients. Significant degeneration was radiologically detected in one patient per group. No tunnel widening was seen in any patient. Up to 97% of all patients were satisfied with the operative procedure. No significant differences were found in the mentioned parameters between the two groups and also in comparison with the 1-year results. The only significant difference was in the donor site morbidity. Significantly more patients in the BPTB group had complaints during kneeling both at 1 (p < 0.001) and 10 years (p = 0.019). Squatting was also subjectively more problematic in the BPTB group than in the QTB group both after 1 (p = 0.003) and 10 years (p = 0.046). CONCLUSIONS: This study shows equally good functional, clinical and radiological long-term results for both hardware-free methods of ACL reconstruction. These results clinically confirm the safety of press-fit anchoring after 10 years. The failure rate in this study was very low, with only one re-rupture in 10 years. The increased donor site morbidity when using the BPTB autograft compared to the QTB autograft supports already reported data. It was also seen in this study for the implant-free press-fit techniques. STUDY DESIGN: Prospective and randomized, level of evidence 2.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior , Ligamento Patelar/transplante , Transplante Autólogo , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Reconstrução do Ligamento Cruzado Anterior/métodos , Reconstrução do Ligamento Cruzado Anterior/estatística & dados numéricos , Humanos , Articulação do Joelho/cirurgia , Complicações Pós-Operatórias , Estudos Prospectivos , Músculo Quadríceps/cirurgia , Volta ao Esporte/estatística & dados numéricos , Tendões/transplante , Transplante Autólogo/efeitos adversos , Transplante Autólogo/métodos , Transplante Autólogo/estatística & dados numéricos
7.
Exp Econ ; 23(1): 30-52, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32055232

RESUMO

There is a heated debate on whether markets erode social responsibility and moral behavior. However, it is a challenging task to identify and measure moral behavior in markets. Based on a theoretical model, we examine in an experiment the relation between trading volume, prices and moral behavior by setting up markets that either impose a negative externality on third parties or not. We find that moral behavior reveals itself in lower trading volume in markets with a negative externality, while prices mostly depend on the market structure. We further investigate individual characteristics that explain trading behavior in markets with negative externalities.

8.
Sci Data ; 6(1): 106, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31263104

RESUMO

There is an ongoing debate about the replicability of neuroimaging research. It was suggested that one of the main reasons for the high rate of false positive results is the many degrees of freedom researchers have during data analysis. In the Neuroimaging Analysis Replication and Prediction Study (NARPS), we aim to provide the first scientific evidence on the variability of results across analysis teams in neuroscience. We collected fMRI data from 108 participants during two versions of the mixed gambles task, which is often used to study decision-making under risk. For each participant, the dataset includes an anatomical (T1 weighted) scan and fMRI as well as behavioral data from four runs of the task. The dataset is shared through OpenNeuro and is formatted according to the Brain Imaging Data Structure (BIDS) standard. Data pre-processed with fMRIprep and quality control reports are also publicly shared. This dataset can be used to study decision-making under risk and to test replicability and interpretability of previous results in the field.


Assuntos
Encéfalo/diagnóstico por imagem , Neuroimagem , Encéfalo/fisiologia , Mapeamento Encefálico , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Valor Preditivo dos Testes
9.
Exp Econ ; 22(1): 76-100, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30828259

RESUMO

With a novel experimental design we investigate whether risk perception, return expectations, and investment propensity are influenced by the scale of the vertical axis in charts. We explore this for two presentation formats, namely return charts and price charts, where we depict low- and high-volatility assets with distinct trends. We find that varying the scale strongly affects people's risk perception, as a narrower scale of the vertical axis leads to significantly higher perceived riskiness of an asset even if the underlying volatility is the same. Furthermore, past returns predict future return expectations almost perfectly. In our setting perceived profitability was considered more important than perceived riskiness when making investment choices. Overall we show that adapting the scale of a chart makes it easier to recognize yearly return variations within a single security, but at the same time makes it harder to identify differences between dissimilar securities. This is something regulators should be aware of and take into account in the rules they set.

10.
Knee Surg Sports Traumatol Arthrosc ; 27(11): 3527-3535, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30820606

RESUMO

PURPOSE: Due to the increased importance of revision ACL reconstruction, this study aims to evaluate the outcome 4 years after the surgery, compare two revision strategies and identify factors that influence the results. METHODS: Seventy-nine patients who received a revision ACL reconstruction were retrospectively evaluated. All patients were assessed with an average follow-up of 4.4 years (range 3.3-5.5 years). The results of patients treated with a quadriceps autograft were compared with those treated with a hamstring autograft. RESULTS: Ninety-seven percent of patients had a KT-1000 side-to-side difference of ≤ 5 mm (mean 1.7 ± 2.0 mm). Pivot-shift test was absent or minor in 95%. In the SLTH-test, 70% of patients reached 90% of the contralateral side. The mean Lysholm score on follow-up was 83 ± 12 (56% excellent/good). The mean IKDC 2000 subjective evaluation score was 81 ± 14 (58% normal/almost normal). The median Tegner activity score was 6 (range 3-10), a median of 2 levels worse than before the first injury. Return to sport rate was 89% but only 34% of patients reached their pre-injury sport level. Most common cause for this reduction was fear of another injury. Three patients suffered a re-rupture. Patients with a hamstring autograft performed pivoting sports more often, but had worse pivot-shift results compared to those with a quadriceps autograft. No significant influence was seen for other parameters. Young, male patients with a high activity level and no chondral damage had the best results. CONCLUSION: Through revision ACL reconstruction, the goal of stabilizing the knee can be achieved in the majority of patients. However, a good function and a high activity level are significantly less common in these patients. The main reason for this is fear of a renewed ACL-injury. Both quadriceps and hamstring autografts were able to achieve a good outcome. Young, male, patients with a normal BMI, a high activity level and without cartilage damage seem to benefit the most from revision ACL surgery. The discrepancy between the good laxity restoration and the lower activity rate should therefore be a main point in clinical counseling when deciding for or against revision ACL-Reconstruction. LEVEL OF EVIDENCE: III.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Traumatismos em Atletas/cirurgia , Músculos Isquiossurais/transplante , Músculo Quadríceps/transplante , Volta ao Esporte , Adulto , Feminino , Humanos , Escore de Lysholm para Joelho , Masculino , Reoperação , Estudos Retrospectivos , Transplante Autólogo
11.
BMC Musculoskelet Disord ; 19(1): 368, 2018 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-30314478

RESUMO

BACKGROUND: The use of a quadriceps tendon-patellar bone (QTPB) autograft provides an alternative procedure in primary reconstruction of the anterior cruciate ligament (ACL). Using the press-fit technique for femoral fixation and knotting over a bone bridge as well as additional spongiosa filling for tibial fixation can completely eliminate the need for fixation implants. The objective of this study was to evaluate the long-term clinical, functional and radiological results of this operating method. METHODS: Sixty-nine patients (27 female-42 male) were included in this study. Fifty-seven patients (83%) received a comprehensive follow-up review after an average period of 7.5 years (range: 7-8.7). All other patients were surveyed by telephone. Six patients (9%) suffered a re-rupture of the ACL graft caused by a new related trauma and were therefore excluded from the statistical analysis. RESULTS: Of all patients, 98% were satisfied with the operation. Normal or almost normal results were recorded in the subjective IKDC scores form by 88% of the patients. The Lysholm score demonstrated very good and good results in 83% of the patients. Only 1 patient reported minor complaints in the donor area. Seven (12%) patients developed Cyclops syndrome with limited knee extension. This complication was treated arthroscopically within the first year postoperatively. Their results on follow-up were not worse than the results of the patients without Cyclops syndrome. Regarding the 57 patients who received a comprehensive evaluation, the stability test with the KT-1000 Arthrometer yielded a difference of less than 3 mm in the contralateral comparison for 89% of the operated knees. The pivot-shift test was normal in 79% and almost normal in 21%. In the Single-leg Triple Hop Test, patients achieved an average of 98% of the hopping distance attained with the contralateral leg. The radiological examination revealed a slight deterioration in the Kellgren-Lawrence Score in 2 patients. CONCLUSION: The ACL reconstruction using the QTPB autograft performed with the press-fit technique leads to good results in comparison with published results of established procedures for primary ACL surgery using other autografts. Further investigations should involve comparative studies with the objective of providing evidence-based, individually adapted therapy for ACL rupture.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Instabilidade Articular/epidemiologia , Patela/transplante , Ligamento Patelar/transplante , Adolescente , Adulto , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Autoenxertos , Feminino , Seguimentos , Humanos , Instabilidade Articular/etiologia , Instabilidade Articular/fisiopatologia , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Masculino , Amplitude de Movimento Articular , Estudos Retrospectivos , Transplante Autólogo/efeitos adversos , Transplante Autólogo/métodos , Resultado do Tratamento , Adulto Jovem
12.
Nat Hum Behav ; 2(9): 637-644, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-31346273

RESUMO

Being able to replicate scientific findings is crucial for scientific progress1-15. We replicate 21 systematically selected experimental studies in the social sciences published in Nature and Science between 2010 and 201516-36. The replications follow analysis plans reviewed by the original authors and pre-registered prior to the replications. The replications are high powered, with sample sizes on average about five times higher than in the original studies. We find a significant effect in the same direction as the original study for 13 (62%) studies, and the effect size of the replications is on average about 50% of the original effect size. Replicability varies between 12 (57%) and 14 (67%) studies for complementary replicability indicators. Consistent with these results, the estimated true-positive rate is 67% in a Bayesian analysis. The relative effect size of true positives is estimated to be 71%, suggesting that both false positives and inflated effect sizes of true positives contribute to imperfect reproducibility. Furthermore, we find that peer beliefs of replicability are strongly related to replicability, suggesting that the research community could predict which results would replicate and that failures to replicate were not the result of chance alone.


Assuntos
Reprodutibilidade dos Testes , Pesquisa/estatística & dados numéricos , Ciências Sociais/estatística & dados numéricos , Teorema de Bayes , Humanos , Publicações Periódicas como Assunto/estatística & dados numéricos , Tamanho da Amostra , Ciências Sociais/métodos
13.
Econ J (London) ; 127(605): F610-F631, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29200470

RESUMO

The effects of a financial transaction tax (FTT) are scientifically disputed, as seemingly small details of its implementation may matter a lot. In this article, we provide experimental evidence on the different effects of an FTT, depending on whether it is implemented as a tax on markets, on residents, or a combination of both. We find that a tax on markets has negative effects on volatility and trading volume, whereas a tax on residents shows none of these undesired effects. Additionally, we observe that individual risk attitude is not related to traders' reaction to the different forms of an FTT.

14.
Science ; 351(6280): 1433-6, 2016 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-26940865

RESUMO

The replicability of some scientific findings has recently been called into question. To contribute data about replicability in economics, we replicated 18 studies published in the American Economic Review and the Quarterly Journal of Economics between 2011 and 2014. All of these replications followed predefined analysis plans that were made publicly available beforehand, and they all have a statistical power of at least 90% to detect the original effect size at the 5% significance level. We found a significant effect in the same direction as in the original study for 11 replications (61%); on average, the replicated effect size is 66% of the original. The replicability rate varies between 67% and 78% for four additional replicability indicators, including a prediction market measure of peer beliefs.

15.
J Int Money Finance ; 31(5): 1279-1298, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26523081

RESUMO

In this paper we explore the influence of the possibility to short stocks and/or borrow money in laboratory markets. A key innovation of our study is that subjects can simultaneously trade two risky assets on two double-auction markets, allowing us to differentiate between assets with relatively high versus low capitalization. Divergence of opinions is created by providing each trader with noisy information on the intrinsic values of both assets. We find that when borrowing money or shorting stocks is restricted prices are systematically distorted. Specifically, stocks with high (low) capitalization are traded at lower (higher) prices than their fundamental value. Lifting the restrictions leads to more efficient prices and more liquidity, thereby also lowering volatility and bid-ask spreads.

16.
J Econ Dyn Control ; 36(8): 1248-1266, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23565012

RESUMO

As the introduction of financial transaction taxes is increasingly discussed by political leaders we explore possible consequences such taxes could have on markets. Here we examine how "stylized facts", namely fat tails and volatility clustering, are affected by different tax regimes in laboratory experiments. We find that leptokurtosis of price returns is highest and clustered volatility is weakest in unilaterally taxed markets (where tax havens exist). Instead, tails are slimmest and volatility clustering is strongest in tax havens. When an encompassing financial transaction tax is levied, stylized facts hardly change compared to a scenario with no tax on all markets.

17.
World J Surg ; 35(10): 2306-14, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21850602

RESUMO

BACKGROUND: The purpose of the study was to determine the incidence of any unplanned reoperation or reintervention procedure after pancreatic resection and to identify the underlying risk factors. METHODS: A total of 189 consecutive pancreatic resections performed from 2001-2008 were searched for any unplanned reoperation, percutaneous drainage, or angiographic reintervention. A retrospective analysis of a prospectively maintained database, including patient characteristics, comorbidities, details of surgery, specific complications, incidence of reoperation/reintervention, and mortality was performed. RESULTS: Overall rates of reoperation, reintervention, and mortality were 6.3% (12/189), 7.9% (15/189), and 1.6% (3/189), respectively. Four patients underwent reintervention and reoperation, so the combined reoperation/reintervention rate was 12.2% (23/189). Reoperation (P < 0.001) and reintervention (P = 0.002) correlated with mortality. Hemorrhage (relative risk [RR], 58; P = 0.0017) and the combination of hemorrhage and pancreatic fistula (RR, 117; P < 0.0001) were identified as risk factors for unplanned reoperation, hemorrhage (RR, 82; P = 0.005), pancreatic fistula (RR, 42; P < 0.001), and the combination of both complications (RR, 246; P < 0.001) for reoperation and/or reintervention. Other patient- or procedure-related factors did not influence the reoperation and/or reintervention rates significantly. CONCLUSIONS: Pancreatic fistula and hemorrhage are the predominant factors that afford unplanned reoperation/reintervention. Although reporting the incidence of unplanned reoperation will include the most severe postoperative complications, a considerable number of reinterventions are missed. Therefore, in outcome analyses of pancreatic surgery, not only reoperations but also any interventional therapies should be included.


Assuntos
Pancreatectomia/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatectomia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Reoperação , Estudos Retrospectivos , Fatores de Risco
18.
J Econ Behav Organ ; 80(3): 586-602, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22210970

RESUMO

TRADING IN FX MARKETS IS DOMINATED BY TWO MICROSTRUCTURES: exchanges with market makers and OTC-markets without market makers. Using laboratory experiments we test whether the impact of a Tobin tax is different in these two market microstructures. We find that (i) in markets without market makers an unilaterally imposed Tobin tax (i.e. a tax haven exists) increases volatility. (ii) In contrast, in markets with market makers we observe a decrease in volatility in unilaterally taxed markets. (iii) An encompassing Tobin tax has no impact on volatility in either setting. Efficiency does not vary significantly across tax regimes.

19.
BMC Cancer ; 10: 348, 2010 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-20598117

RESUMO

BACKGROUND: Deregulated c-Myc expression is a hallmark of several human cancers where it promotes proliferation and an aggressive tumour phenotype. Myc overexpression is associated with reduced activity of Rel/NF-kappaB, transcription factors that control the immune response, cell survival, and transformation, and that are frequently altered in cancer. The Rel/NF-kappaB family member NFKB2 is altered by chromosomal translocations or deletions in lymphoid malignancies and deletion of the C-terminal ankyrin domain of NF-kappaB2 augments lymphocyte proliferation. METHODS: Precancerous Emicro-Myc-transgenic B cells, Emicro-Myc lymphomas and human Burkitt lymphoma samples were assessed for Nfkb2 expression. The contribution of Nfkb2 to Myc-driven apoptosis, proliferation, and lymphomagenesis was tested genetically in vivo. RESULTS: Here we report that the Myc oncoprotein suppresses Nfkb2 expression in vitro in primary mouse fibroblasts and B cells, and in vivo in the Emicro-Myc transgenic mouse model of human Burkitt lymphoma (BL). NFKB2 suppression by Myc was also confirmed in primary human BL. Promoter-reporter assays indicate that Myc-mediated suppression of Nfkb2 occurs at the level of transcription. The contribution of Nfkb2 to Myc-driven lymphomagenesis was tested in vivo, where Nfkb2 loss was shown to accelerate lymphoma development in Emicro-Myc transgenic mice, by impairing Myc's apoptotic response. CONCLUSIONS: Nfkb2 is suppressed by c-Myc and harnesses Myc-driven lymphomagenesis. These data thus link Myc-driven lymphomagenesis to the non-canonical NF-kappaB pathway.


Assuntos
Apoptose , Linfoma de Burkitt/metabolismo , Proliferação de Células , Subunidade p52 de NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Linfócitos B/metabolismo , Linfócitos B/patologia , Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , Células Cultivadas , Regulação para Baixo , Fibroblastos/metabolismo , Fibroblastos/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Subunidade p52 de NF-kappa B/deficiência , Subunidade p52 de NF-kappa B/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myc/genética , RNA Mensageiro/metabolismo , Fatores de Tempo , Transcrição Gênica , Transfecção
20.
Surg Infect (Larchmt) ; 7(3): 263-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16875459

RESUMO

BACKGROUND: Unplanned reoperation is perceived as a quality indicator for surgical procedures. However, there is a lack of data regarding the extent to which infections add to the reoperation rate. We studied the role of infection as an indication for unplanned reoperation. METHODS: The setting was a surgical department at an academic teaching hospital performing a spectrum of general, vascular, thoracic (lung), and transplant (kidney) procedures. Between January, 2003 and September, 2004, data on operations, unplanned reoperations, and complications were documented prospectively. Unplanned reoperation was defined as unexpected reoperation within 30 days of the primary procedure. Endpoints were the number of unplanned reoperations attributable to infection, the site of the infection, the type of the primary operation, and deaths. RESULTS: A total of 6,287 operations were performed during the study period. The rate of unplanned reoperations was 1.34% (84/6287), and 15 (17.9%) of these 84 patients had to undergo reoperation because of an infection. The primary operations in these cases were general surgical procedures in 11 patients, kidney transplant in two patients, and vascular surgery and lung resection in one patient each. Leakage of a gastrointestinal anastomosis was the predominant cause in the general surgical group (8/11). The most frequent initial procedure was colon resection (n = 4) followed by ileostomy closure (n = 2) and kidney transplant (n = 2). One unplanned reoperation had to be done after esophagectomy, pancreatoduodenectomy, pneumonectomy, incisional hernia repair, appendectomy, femoro-femoral bypass, and resection of a soft tissue tumor. The mortality rate after unplanned reoperation for infection was 20% (3/15), a significantly higher rate than in patients not having reoperation (p < 0.00001). Subgroup analysis did not show any significant difference in mortality according to whether the unplanned reoperation was indicated by infection, bleeding, or other reason (p = 0.28). Patients who required operation because of an infection stayed significantly longer in the intensive care unit (p = 0.018) and underwent more reoperations (p = 0.003) than those with other indications for reoperation. CONCLUSION: Infections add considerably to the rate of unplanned reoperation. The mortality rate is high, but not significantly different from that in patients having reoperation for other indications. A longer stay in the intensive care unit and a higher number of reoperations indicate a greater use of resources by these patients.


Assuntos
Infecções Bacterianas/cirurgia , Complicações Pós-Operatórias/cirurgia , Reoperação/estatística & dados numéricos , APACHE , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas/mortalidade , Coleta de Dados , Feminino , Hospitais Universitários , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Estudos Prospectivos , Garantia da Qualidade dos Cuidados de Saúde , Reoperação/mortalidade , Estudos Retrospectivos , Fatores Sexuais , Resultado do Tratamento
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