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Ghneim M, Kufera J, Zhang A, Penaloza-Villalobos L, Swentek L, Watras J, Smith A, Hahn A, Rodriguez Mederos D, Dickhudt TJ, Laverick P, Cunningham K, Norwood S, Fernandez L, Jacobson LE, Williams JM, Lottenberg L, Azar F, Shillinglaw W, Slivinski A, Nahmias J, Donnelly M, Bala M, Egodage T, Zhu C, Udekwu PO, Norton H, Dunn JA, Baer R, McBride K, Santos AP, Shrestha K, Metzner CJ, Murphy JM, Schroeppel TJ, Stillman Z, O'Connor R, Johnson D, Berry C, Ratner M, Reynolds JK, Humphrey M, Scott M, Hickman ZL, Twelker K, Legister C, Glass NE, Siebenburgen C, Palmer B, Semon GR, Lieser M, McDonald H, Bugaev N, LeClair MJ, Stein D. Does lower extremity fracture fixation technique influence neurologic outcomes in patients with traumatic brain injury? The EAST Brain vs. Bone multicenter trial. J Trauma Acute Care Surg 2023; 95:516-523. [PMID: 37335182 DOI: 10.1097/ta.0000000000004095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2023]
Abstract
OBJECTIVE This study aimed to determine whether lower extremity fracture fixation technique and timing (≤24 vs. >24 hours) impact neurologic outcomes in TBI patients. METHODS A prospective observational study was conducted across 30 trauma centers. Inclusion criteria were age 18 years and older, head Abbreviated Injury Scale (AIS) score of >2, and a diaphyseal femur or tibia fracture requiring external fixation (Ex-Fix), intramedullary nailing (IMN), or open reduction and internal fixation (ORIF). The analysis was conducted using analysis of variamce, Kruskal-Wallis, and multivariable regression models. Neurologic outcomes were measured by discharge Ranchos Los Amigos Revised Scale (RLAS-R). RESULTS Of the 520 patients enrolled, 358 underwent Ex-Fix, IMN, or ORIF as definitive management. Head AIS was similar among cohorts. The Ex-Fix group experienced more severe lower extremity injuries (AIS score, 4-5) compared with the IMN group (16% vs. 3%, p = 0.01) but not the ORIF group (16% vs. 6%, p = 0.1). Time to operative intervention varied between the cohorts with the longest time to intervention for the IMN group (median hours: Ex-Fix, 15 [8-24] vs. ORIF, 26 [12-85] vs. IMN, 31 [12-70]; p < 0.001). The discharge RLAS-R score distribution was similar across the groups. After adjusting for confounders, neither method nor timing of lower extremity fixation influenced the discharge RLAS-R. Instead, increasing age and head AIS score were associated with a lower discharge RLAS-R score (odds ratio [OR], 1.02; 95% confidence interval [CI], 1.002-1.03 and OR, 2.37; 95% CI, 1.75-3.22), and a higher Glasgow Coma Scale motor score on admission (OR, 0.84; 95% CI, 0.73-0.97) was associated with higher RLAS-R score at discharge. CONCLUSION Neurologic outcomes in TBI are impacted by severity of the head injury and not the fracture fixation technique or timing. Therefore, the strategy of definitive fixation of lower extremity fractures should be dictated by patient physiology and the anatomy of the injured extremity and not by the concern for worsening neurologic outcomes in TBI patients. LEVEL OF EVIDENCE Prognostic and Epidemiological; Level III.
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Affiliation(s)
- Mira Ghneim
- From the R Adams Cowley Shock Trauma Center (M.G., D.S.), Program in Trauma, Department of Surgery, University of Maryland School of Medicine; National Study Center for Trauma and Emergency Medical Systems, Program in Trauma, Center for Shock, Trauma and Anesthesiology Research (J.K.), University of Maryland School of Medicine; University of Maryland School of Medicine (A.Z.); Department of Surgery (L.P.-V., L.S.), Loma Linda University Medical Center; Inova Fairfax Hospital (J.W.); LSUHCS (A.S.); Ochsner Medical Center (A.H.); Broward Health Medical Center (D.R.M., T.J.D.); Atrium Health Carolinas Medical Center (P.L., K.C.); University of Texas Health Science Center (S.N., L.F.); Ascension St. Vincent Hospital (L.E.J., J.M.W.); St. Mary's Medical Center (L.L., F.A.), Florida Atlantic University, Schmidt College of Medicine; Mission Hospital (W.S., A.S.); University of California, Irvine (J.N., M.D.); Hadassah Medical Center and Faculty of Medicine (M.B.), Hebrew University of Jerusalem; Cooper University Health Care (T.E.); Cooper University Health Care (C.Z.); WakeMed Health and Hospitals (P.O.U., H.N.); Medical Center of the Rockies (J.A.D.), University of Colorado Health North; Orthopedic Center of the Rockies (R.B.); Memorial University Medical Center (K.M.); Texas Tech University Health Sciences Center (A.P.S., K.S.); Spartanburg Regional Medical Center (C.J.M., J.M.M.); Memorial Hospital Central (T.J.S., Z.S.); Yale School of Medicine (R.O., D.J.); NYU Grossman School of Medicine (C.B., M.R.,); University of Kentucky (J.K.R., M.H.); St. Mary's Medical Center (M.S.), Essentia Health; NYC Health + Hospitals/Elmhurst (Z.L.H., K.T.), Icahn School of Medicine at Mount Sinai; Rutgers New Jersey Medical School (C.L., N.E.G.); Kettering Health Main Campus (C.S., B.P.); Wright State University Boonshoft School of Medicine (G.R.S.); Research Medical Center (M.L., H.M.); Tufts Medical Center (N.B.), Tuft University School of Medicine; and Tufts Medical Center (M.J.L.)
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Milling TJ, Middeldorp S, Xu L, Koch B, Demchuk A, Eikelboom JW, Verhamme P, Cohen AT, Beyer-Westendorf J, Michael Gibson C, Lopez-Sendon J, Crowther M, Shoamanesh A, Coppens M, Schmidt J, Albaladejo P, Connolly SJ, Bastani A, Clark C, Concha M, Cornell J, Dombrowski K, Fermann G, Fulmer J, Goldstein J, Kereiakes D, Milling T, Pallin D, Patel N, Refaai M, Rehman M, Schmaier A, Schwarz E, Shillinglaw W, Spohn M, Takata T, Venkat A, Welker J, Welsby I, Wilson J, Van Keer L, Verschuren F, Blostein M, Eikelboom J, Althaus K, Berrouschot J, Braun G, Doeppner T, Dziewas R, Genth-Zotz S, Greinacher P, Hamann F, Hanses F, Heide W, Kallmuenzer B, Kermer P, Poli S, Royl G, Schellong S, Schnupp S, Schwarze J, Spies C, Thomalla G, von Mering M, Weissenborn K, Wollenweber F, Gumbinger C, Jaschinski U, Maschke M, Mochmann HC, Pfeilschifter W, Pohlmann C, Zahn R, Bouzat P, Schmidt J, Vallejo C, Floccard B, Coppens M, van Wissen S, Arellano-Rodrigo E, Valles E, Alikhan R, Breen K, Hall R, Crowther M, Albaladejo P, Cohen A, Demchuk A, Schmidt J, Wyse D, Garcia D, Prins M, Nakamya J, Büller H, Mahaffey KW, Alexander JH, Cairns J, Hart R, Joyner C, Raskob G, Schulman S, Veltkamp R, Meeks B, Zotova E, Ahmad S, Pinto T, Baker K, Dykstra A, Holadyk-Gris I, Malvaso A, Demchuk A. Final Study Report of Andexanet Alfa for Major Bleeding With Factor Xa Inhibitors. Circulation 2023; 147:1026-1038. [PMID: 36802876 DOI: 10.1161/circulationaha.121.057844] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
BACKGROUND Andexanet alfa is a modified recombinant inactive factor Xa (FXa) designed to reverse FXa inhibitors. ANNEXA-4 (Andexanet Alfa, a Novel Antidote to the Anticoagulation Effects of Factor Xa Inhibitors) was a multicenter, prospective, phase-3b/4, single-group cohort study that evaluated andexanet alfa in patients with acute major bleeding. The results of the final analyses are presented. METHODS Patients with acute major bleeding within 18 hours of FXa inhibitor administration were enrolled. Co-primary end points were anti-FXa activity change from baseline during andexanet alfa treatment and excellent or good hemostatic efficacy, defined by a scale used in previous reversal studies, at 12 hours. The efficacy population included patients with baseline anti-FXa activity levels above predefined thresholds (≥75 ng/mL for apixaban and rivaroxaban, ≥40 ng/mL for edoxaban, and ≥0.25 IU/mL for enoxaparin; reported in the same units used for calibrators) who were adjudicated as meeting major bleeding criteria (modified International Society of Thrombosis and Haemostasis definition). The safety population included all patients. Major bleeding criteria, hemostatic efficacy, thrombotic events (stratified by occurring before or after restart of either prophylactic [ie, a lower dose, for prevention rather than treatment] or full-dose oral anticoagulation), and deaths were assessed by an independent adjudication committee. Median endogenous thrombin potential at baseline and across the follow-up period was a secondary outcome. RESULTS There were 479 patients enrolled (mean age, 78 years; 54% male, 86% White; 81% anticoagulated for atrial fibrillation at a median time of 11.4 hours since last dose, with 245 (51%) on apixaban, 176 (37%) on rivaroxaban, 36 (8%) on edoxaban, and 22 (5%) on enoxaparin. Bleeding was predominantly intracranial (n=331 [69%]) or gastrointestinal (n=109 [23%]). In evaluable apixaban patients (n=172), median anti-FXa activity decreased from 146.9 ng/mL to 10.0 ng/mL (reduction, 93% [95% CI, 94-93]); in rivaroxaban patients (n=132), it decreased from 214.6 ng/mL to 10.8 ng/mL (94% [95% CI, 95-93]); in edoxaban patients (n=28), it decreased from 121.1 ng/mL to 24.4 ng/mL (71% [95% CI, 82-65); and in enoxaparin patients (n=17), it decreased from 0.48 IU/mL to 0.11 IU/mL (75% [95% CI, 79-67]). Excellent or good hemostasis occurred in 274 of 342 evaluable patients (80% [95% CI, 75-84]). In the safety population, thrombotic events occurred in 50 patients (10%); in 16 patients, this occurred during treatment with prophylactic anticoagulation that began after the bleeding event. No thrombotic episodes occurred after oral anticoagulation restart. Specific to certain populations, reduction of anti-FXa activity from baseline to nadir significantly predicted hemostatic efficacy in patients with intracranial hemorrhage (area under the receiver operating characteristic curve, 0.62 [95% CI, 0.54-0.70]) and correlated with lower mortality in patients <75 years of age (adjusted P=0.022; unadjusted P=0.003). Median endogenous thrombin potential was within the normal range by the end of andexanet alfa bolus through 24 hours for all FXa inhibitors. CONCLUSIONS In patients with major bleeding associated with the use of FXa inhibitors, treatment with andexanet alfa reduced anti-FXa activity and was associated with good or excellent hemostatic efficacy in 80% of patients. REGISTRATION URL: https://www. CLINICALTRIALS gov; Unique identifier: NCT02329327.
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Affiliation(s)
- Truman J Milling
- Seton Dell Medical School Stroke Institute, Dell Medical School, University of Texas at Austin (T.J.M.)
| | - Saskia Middeldorp
- Department of Internal Medicine and Radboud Institute of Health Sciences, Nijmegenthe Netherlands (S.M.)
| | - Lizhen Xu
- Population Health Research Institute, McMaster University, HamiltonOntario Canada. (L.X., A.S., S.J.C.)
| | - Bruce Koch
- Alexion, AstraZeneca Rare Disease, BostonMA (B.K.)
| | - Andrew Demchuk
- Departments of Clinical Neurosciences and Radiology, Cumming School of Medicine, University of Calgary, AlbertaCanada (A.D.)
| | - John W Eikelboom
- Department of Medicine, McMaster University, HamiltonOntario Canada. (J.W.E., M. Crowther)
| | - Peter Verhamme
- Center for Molecular and Vascular Biology, University of Leuven, Belgium (P.V.)
| | | | - Jan Beyer-Westendorf
- Department of Medicine I, Division of Hematology and Hemostasis, University Hospital Dresden, Germany (J.B-W.)
| | | | - Jose Lopez-Sendon
- Instituto de Investigación Hospital Universitario, La PazMadridSpain (J. L-S.)
| | - Mark Crowther
- Department of Medicine, McMaster University, HamiltonOntario Canada. (J.W.E., M. Crowther)
| | - Ashkan Shoamanesh
- Population Health Research Institute, McMaster University, HamiltonOntario Canada. (L.X., A.S., S.J.C.)
| | - Michiel Coppens
- Department of Vascular Medicine, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, University of Amsterdam, the Netherlands (M. Coppens)
| | - Jeannot Schmidt
- Centre Hospitalier Universitaire de Clermont-Ferrand, France (J.S.)
| | | | - Stuart J Connolly
- Population Health Research Institute, McMaster University, HamiltonOntario Canada. (L.X., A.S., S.J.C.)
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Yamashita H, Takenoshita M, Sakurai M, Bruick RK, Henzel WJ, Shillinglaw W, Arnot D, Uyeda K. A glucose-responsive transcription factor that regulates carbohydrate metabolism in the liver. Proc Natl Acad Sci U S A 2001; 98:9116-21. [PMID: 11470916 PMCID: PMC55382 DOI: 10.1073/pnas.161284298] [Citation(s) in RCA: 492] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Carbohydrates mediate their conversion to triglycerides in the liver by promoting both rapid posttranslational activation of rate-limiting glycolytic and lipogenic enzymes and transcriptional induction of the genes encoding many of these same enzymes. The mechanism by which elevated carbohydrate levels affect transcription of these genes remains unknown. Here we report the purification and identification of a transcription factor that recognizes the carbohydrate response element (ChRE) within the promoter of the L-type pyruvate kinase (LPK) gene. The DNA-binding activity of this ChRE-binding protein (ChREBP) in rat livers is specifically induced by a high carbohydrate diet. ChREBP's DNA-binding specificity in vitro precisely correlates with promoter activity in vivo. Furthermore, forced ChREBP overexpression in primary hepatocytes activates transcription from the L-type Pyruvate kinase promoter in response to high glucose levels. The DNA-binding activity of ChREBP can be modulated in vitro by means of changes in its phosphorylation state, suggesting a possible mode of glucose-responsive regulation. ChREBP is likely critical for the optimal long-term storage of excess carbohydrates as fats, and may contribute to the imbalance between nutrient utilization and storage characteristic of obesity.
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Affiliation(s)
- H Yamashita
- Dallas Veterans Affairs Medical Center and Department of Biochemistry, University of Texas Southwestern Medical Center, 4500 South Lancaster Road, Dallas, TX 75216, USA
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Mancebo R, Zhou X, Shillinglaw W, Henzel W, Macdonald PM. BSF binds specifically to the bicoid mRNA 3' untranslated region and contributes to stabilization of bicoid mRNA. Mol Cell Biol 2001; 21:3462-71. [PMID: 11313472 PMCID: PMC100268 DOI: 10.1128/mcb.21.10.3462-3471.2001] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The early stages of Drosophila melanogaster development rely extensively on posttranscriptional forms of gene regulation. Deployment of the anterior body patterning morphogen, the Bicoid protein, requires both localization and translational regulation of the maternal bicoid mRNA. Here we provide evidence that the bicoid mRNA is also selectively stabilized during oogenesis. We identify and isolate a protein, BSF, that binds specifically to IV/V RNA, a minimal form of the bicoid mRNA 3' untranslated region that supports a normal program of mRNA localization during oogenesis. Mutations that disrupt the BSF binding site in IV/V RNA or substantially reduce the level of BSF protein lead to reduction in IV/V RNA levels, indicating a role for BSF in RNA stabilization. The BSF protein is novel and lacks all of the characterized RNA binding motifs. However, BSF does include multiple copies of the PPR motif, whose function is unknown but appears in other proteins with roles in RNA metabolism.
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Affiliation(s)
- R Mancebo
- Department of Biological Sciences, Stanford University, Stanford, California 94305, USA
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Li M, Shillinglaw W, Henzel WJ, Beg AA. The Rela(p65) subunit of NF-kappaB is essential for inhibiting double-stranded RNA-induced cytotoxicity. J Biol Chem 2001; 276:1185-94. [PMID: 11035014 DOI: 10.1074/jbc.m006647200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Double-stranded RNA (dsRNA) molecules generated during virus infection can initiate a host antiviral response to limit further infection. Such a response involves induction of antiviral gene expression by the dsRNA-activated protein kinase (PKR) and the NF-kappaB transcription factor. In addition, dsRNA can also induce apoptosis by an incompletely understood mechanism that may serve to further limit viral replication. Here we demonstrate a novel role for the RelA subunit of NF-kappaB in inhibiting dsRNA-induced cell death. dsRNA treatment resulted in caspase 3 activation and apoptotic morphological transformations in mouse embryonic fibroblasts (MEFs) derived from RelA-/- mice but not from RelA+/+ mice. Such dsRNA-induced killing could be inhibited by expression of either a dominant-negative mutant of PKR or wild-type RelA. Interestingly, caspase 3 activated following dsRNA treatment of RelA-/- MEFs was essential for apoptotic nuclear changes but dispensable for cytotoxicity. A broader specificity caspase inhibitor was also unable to inhibit dsRNA-induced cytotoxicity, suggesting that caspase activation is not essential for the induction of cell death by dsRNA in MEFs. However, combined inhibition of caspase 3 and reactive oxygen species production resulted in complete inhibition of dsRNA-induced cytotoxicity. These results demonstrate an essential role for NF-kappaB in protecting cells from dsRNA-induced apoptosis and suggest that NF-kappaB may inhibit both caspase-dependent and reactive oxygen species-dependent cytotoxic pathways.
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Affiliation(s)
- M Li
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
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Bonnard M, Mirtsos C, Suzuki S, Graham K, Huang J, Ng M, Itié A, Wakeham A, Shahinian A, Henzel WJ, Elia AJ, Shillinglaw W, Mak TW, Cao Z, Yeh WC. Deficiency of T2K leads to apoptotic liver degeneration and impaired NF-kappaB-dependent gene transcription. EMBO J 2000; 19:4976-85. [PMID: 10990461 PMCID: PMC314216 DOI: 10.1093/emboj/19.18.4976] [Citation(s) in RCA: 294] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Induction of NF-kappaB-dependent transcription requires phosphorylation and subsequent degradation of I-kappaB, an inhibitor of NF-kappaB, followed by nuclear translocation and DNA binding of NF-kappaB. Tumor necrosis factor receptor-associated factor 2 (TRAF2) plays a role in NF-kappaB activation in response to cytokines such as tumor necrosis factor alpha (TNFalpha). In this study, we purified and characterized a novel kinase (T2K, also known as TBK1 or NAK), which associates with TRAF2 and exhibits kinase activity towards I-kappaBalpha in vitro. The physiological function of T2K was investigated using T2K-deficient mice. Heterozygotes appear normal, but t2k(-/-) animals die at approximately E14.5 of massive liver degeneration and apoptosis. Never theless, hematopoietic progenitors from T2K-deficient fetal liver support normal lymphocyte development. Furthermore, t2k(-/-) embryonic fibroblasts and thymocytes do not display increased sensitivity to TNFalpha-induced apoptosis. In response to either TNFalpha or IL-1 induction, t2k(-/-) embryonic fibroblasts exhibit normal degradation of I-kappaB and kappaB-binding activity. However, NF-kappaB-directed transcription is dramatically reduced. These results demonstrate that, like I-kappaB kinase beta and the RelA subunit of NF-kappaB, T2K is critical in protecting embryonic liver from apoptosis. However, T2K has a unique role in the activation of NF-kappaB-directed transcription, apparently independent of I-kappaB degradation and NF-kappaB DNA binding.
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Affiliation(s)
- M Bonnard
- Amgen Institute, Ontario Cancer Institute and the Department of Medical Biophysics, University of Toronto, 620 University Avenue, Toronto, Ontario, Canada
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Smibert CA, Lie YS, Shillinglaw W, Henzel WJ, Macdonald PM. Smaug, a novel and conserved protein, contributes to repression of nanos mRNA translation in vitro. RNA 1999; 5:1535-1547. [PMID: 10606265 PMCID: PMC1369876 DOI: 10.1017/s1355838299991392] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Proper deployment of Nanos protein at the posterior of the Drosophila embryo, where it directs posterior development, requires a combination of RNA localization and translational controls. These controls ensure that only the posteriorly-localized nanos mRNA is translated, whereas unlocalized nanos mRNA is translationally repressed. Here we describe cloning of the gene encoding Smaug, an RNA-binding protein that interacts with the sequences, SREs, in the nanos mRNA that mediate translational repression. Using an in vitro translation assay, we demonstrate that SRE-dependent repression occurs in extracts from early stage embryos. Immunodepletion of Smaug from the extracts eliminates repression, consistent with the notion that Smaug is involved. Smaug is a novel gene and the existence of potential mammalian Smaug homologs raises the possibility that Smaug represents a new class of conserved translational repressor.
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Affiliation(s)
- C A Smibert
- Department of Biological Sciences, Stanford University, California 94305-5020, USA
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Abstract
Reaper is a central regulator of apoptosis in Drosophila melanogaster. With no obvious catalytic activity or homology to other known apoptotic regulators, reaper's mechanism of action has been obscure. We recently reported that recombinant Drosophila reaper protein induced rapid mitochondrial cytochrome c release, caspase activation and apoptotic nuclear fragmentation in extracts of Xenopus eggs. We now report the purification of a 150 kDa reaper-interacting protein from Xenopus egg extracts, which we have named Scythe. Scythe is highly conserved among vertebrates and contains a ubiquitin-like domain near its N-terminus. Immunodepletion of Scythe from extracts completely prevented reaper-induced apoptosis without affecting apoptosis triggered by activated caspases. Moreover, a truncated variant of Scythe lacking the N-terminal domain induced apoptosis even in the absence of reaper. These data suggest that Scythe is a novel apoptotic regulator that is an essential component in the pathway of reaper-induced apoptosis.
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Affiliation(s)
- K Thress
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, C366 LSRC, Research Drive, Durham, NC 27710, USA
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Elliott DC, Rodriguez A, Moncure M, Myers RA, Shillinglaw W, Davis F, Goldberg A, Mitchell K, McRitchie D. The accuracy of diagnostic laparoscopy in trauma patients: a prospective, controlled study. Int Surg 1998; 83:294-8. [PMID: 10096745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
BACKGROUND Numerous studies advocate the use of diagnostic laparoscopy (DL) for abdominal trauma, but none have documented its ability to diagnose specific injuries. This study tests the hypothesis that DL can accurately identify all significant intra-abdominal injuries in trauma patients. METHODS Of trauma patients requiring laparotomy for presumed injuries, 47 underwent DL followed by laparotomy. Injuries noted at laparoscopy were compared with those found at laparotomy. RESULTS Of these, 14 patients had no significant injuries necessitating operative intervention noted at laparoscopy and celiotomy. The remaining 33 patients harbored 93 significant injuries at laparotomy, of which only 57.0% were found by DL. DL possessed poor sensitivity (<50%) for injuries to hollow viscera. Despite DL's poor performance in finding specific injuries, it possessed excellent sensitivity (96.2%), and specificity (100%) for determining the need for therapeutic celiotomy. CONCLUSIONS DL offers no clear advantage over diagnostic peritoneal lavage and computed tomography in blunt trauma. Its utility lies in assessment of the need for laparotomy in patients with penetrating wounds. Currently, DL cannot consistently identify all abdominal injuries, disqualifying it as a therapeutic tool in abdominal trauma.
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Affiliation(s)
- D C Elliott
- Department of Surgery, R. Adams Cowley Shock Trauma Center, University of Maryland Medical System, Baltimore, USA
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Jiang MS, Tang QQ, McLenithan J, Geiman D, Shillinglaw W, Henzel WJ, Lane MD. Derepression of the C/EBPalpha gene during adipogenesis: identification of AP-2alpha as a repressor. Proc Natl Acad Sci U S A 1998; 95:3467-71. [PMID: 9520389 PMCID: PMC19859 DOI: 10.1073/pnas.95.7.3467] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/31/1997] [Indexed: 02/06/2023] Open
Abstract
During adipogenesis, CCAAT/enhancer binding protein alpha (C/EBPalpha) serves as a pleiotropic transcriptional activator of adipocyte genes. Previously, we identified dual repressive elements in the C/EBPalpha gene and a putative transacting factor (C/EBPalpha undifferentiated protein, or CUP) expressed by preadipocytes, but not adipocytes, that bind to these elements. In the present investigation, CUP was purified 17,000-fold from nuclear extracts of 3T3-L1 preadipocytes. Amino acid sequence and mass spectral analysis of tryptic peptides derived from purifed CUP (molecular mass approximately 50 kDa) revealed that the repressor is (or contains) an isoform of the transcription factor, AP-2alpha. Electrophoretic mobility shift and Western blot analysis on purified CUP and preadipocyte nuclear extracts confirmed the identity of CUP as AP-2alpha. Both AP-2alpha protein and CUP binding activity are expressed by preadipocytes and then decrease concomitantly during differentiation of 3T3-L1 preadipocytes into adipocytes. Consistent with a repressive role of AP-2alpha/CUP, an AP-2alpha1 expression vector, cotransfected with a C/EBPalpha promoter-reporter construct into 3T3-L1 adipocytes, inhibited reporter gene transcription. Taken together with previous results, these findings suggest that in preadipocytes the C/EBPalpha gene is repressed by AP-2alpha/CUP, which, upon induction of differentiation, is down-regulated, allowing expression of the gene.
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Affiliation(s)
- M S Jiang
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Abstract
IL-1 is a proinflammatory cytokine that signals through a receptor complex of two different transmembrane chains to generate multiple cellular responses, including activation of the transcription factor NF-kappaB. Here we show that MyD88, a previously described protein of unknown function, is recruited to the IL-1 receptor complex following IL-1 stimulation. MyD88 binds to both IRAK (IL-1 receptor-associated kinase) and the heterocomplex (the signaling complex) of the two receptor chains and thereby mediates the association of IRAK with the receptor. Ectopic expression of MyD88 or its death domain-containing N-terminus activates NF-kappaB. The C-terminus of MyD88 interacts with the IL-1 receptor and blocks NF-kappaB activation induced by IL-1, but not by TNF. Thus, MyD88 plays the same role in IL-1 signaling as TRADD and Tube do in TNF and Toll pathways, respectively: it couples a serine/threonine protein kinase to the receptor complex.
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Affiliation(s)
- H Wesche
- Tularik, Incorporated, South San Francisco, California 94080, USA
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Riblet JL, Shillinglaw W, Goldberg AJ, Mitchell K, Sedani KH, Davis FE, Reynolds HN. Utility of the routine chest X-ray after "over-wire" venous catheter changes. Am Surg 1996; 62:1064-5. [PMID: 8955250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The Seldinger technique is commonly used to change central venous access catheters in the Intensive Care Unit. These catheters are routinely being changed to prevent septic complications. Some of these changes are performed by an "over-wire" technique. To assess the utility of postprocedural chest X-rays on critically ill patients after an over-wire catheter change, we followed 68 patients after they had 80 catheter changes. This study assesses catheter position by use of a postprocedural X-ray. During the study, we found no misplaced catheters and minimum symptomatology in 80 patients. The trauma/critical care fellows performing the procedures rated them as easy in 97.5 percent of the changes. The conclusion of the study is that, if the catheter change is technically easy and the patient has no symptoms, a postprocedural X-ray is not necessary.
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Affiliation(s)
- J L Riblet
- Maryland Institute for Emergency Medical Services Systems, Baltimore, USA
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