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Sullivan NJ, Sasser AK, Axel AE, Vesuna F, Raman V, Ramirez N, Oberyszyn TM, Hall BM. Interleukin-6 induces an epithelial-mesenchymal transition phenotype in human breast cancer cells. Oncogene 2009; 28:2940-7. [PMID: 19581928 DOI: 10.1038/onc.2009.180] [Citation(s) in RCA: 570] [Impact Index Per Article: 35.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Breast tumor interleukin-6 (IL-6) levels increase with tumor grade, and elevated serum IL-6 correlates with poor breast cancer patient survival. Epithelial-mesenchymal transition (EMT) phenotypes such as impaired E-cadherin expression or aberrant Vimentin induction are associated with enhanced metastasis and unfavorable clinical outcome in breast cancer. Despite this fact, few tumor microenvironment-derived extracellular signaling factors capable of provoking such a phenotypic transition have been identified. In this study, we showed that IL-6 promoted E-cadherin repression among a panel of estrogen receptor-alpha-positive human breast cancer cells. Furthermore, ectopic stable IL-6 expressing MCF-7 breast adenocarcinoma cells (MCF-7(IL-6)) exhibited an EMT phenotype characterized by impaired E-cadherin expression and induction of Vimentin, N-cadherin, Snail and Twist. MCF-7(IL-6) cells formed xenograft tumors that displayed loss of E-cadherin, robust Vimentin induction, increased proliferative indices, advanced tumor grade and undifferentiated histology. Finally, we showed aberrant IL-6 production and STAT3 activation in MCF-7 cells that constitutively express Twist, a metastatic regulator and direct transcriptional repressor of E-cadherin. To our knowledge, this is the first study that shows IL-6 as an inducer of an EMT phenotype in breast cancer cells and implicates its potential to promote breast cancer metastasis.
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Research Support, Non-U.S. Gov't |
16 |
570 |
2
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Raman V, Martensen SA, Reisman D, Evron E, Odenwald WF, Jaffee E, Marks J, Sukumar S. Compromised HOXA5 function can limit p53 expression in human breast tumours. Nature 2000; 405:974-8. [PMID: 10879542 DOI: 10.1038/35016125] [Citation(s) in RCA: 366] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Expression of the p53 gene protects cells against malignant transformation. Whereas control of p53 degradation has been a subject of intense scrutiny, little is known about the factors that regulate p53 synthesis. Here we show that p53 messenger RNA levels are low in a large proportion of breast tumours. Seeking potential regulators of p53 transcription, we found consensus HOX binding sites in the p53 promoterS. Transient transfection of Hox/HOXA5 activated the p53 promoter. Expression of HOXA5 in epithelial cancer cells expressing wild-type p53, but not in isogenic variants lacking the p53 gene, led to apoptotic cell death. Moreover, breast cancer cell lines and patient tumours display a coordinate loss of p53 and HOXA5 mRNA and protein expression. The HOXA5 promoter region was methylated in 16 out of 20 p53-negative breast tumour specimens. We conclude that loss of expression of p53 in human breast cancer may be primarily due to lack of expression of HOXA5.
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366 |
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Marcelino J, Carpten JD, Suwairi WM, Gutierrez OM, Schwartz S, Robbins C, Sood R, Makalowska I, Baxevanis A, Johnstone B, Laxer RM, Zemel L, Kim CA, Herd JK, Ihle J, Williams C, Johnson M, Raman V, Alonso LG, Brunoni D, Gerstein A, Papadopoulos N, Bahabri SA, Trent JM, Warman ML. CACP, encoding a secreted proteoglycan, is mutated in camptodactyly-arthropathy-coxa vara-pericarditis syndrome. Nat Genet 1999; 23:319-22. [PMID: 10545950 DOI: 10.1038/15496] [Citation(s) in RCA: 227] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Altered growth and function of synoviocytes, the intimal cells which line joint cavities and tendon sheaths, occur in a number of skeletal diseases. Hyperplasia of synoviocytes is found in both rheumatoid arthritis and osteoarthritis, despite differences in the underlying aetiologies of the two disorders. We have studied the autosomal recessive disorder camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP; MIM 208250) to identify biological pathways that lead to synoviocyte hyperplasia, the principal pathological feature of this syndrome. Using a positional-candidate approach, we identified mutations in a gene (CACP) encoding a secreted proteoglycan as the cause of CACP. The CACP protein, which has previously been identified as both 'megakaryocyte stimulating factor precursor' and 'superficial zone protein', contains domains that have homology to somatomedin B, heparin-binding proteins, mucins and haemopexins. In addition to expression in joint synovium and cartilage, CACP is expressed in non-skeletal tissues including liver and pericardium. The similarity of CACP sequence to that of other protein families and the expression of CACP in non-skeletal tissues suggest it may have diverse biological activities.
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227 |
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Botlagunta M, Vesuna F, Mironchik Y, Raman A, Lisok A, Winnard P, Mukadam S, Van Diest P, Chen JH, Farabaugh P, Patel AH, Raman V. Oncogenic role of DDX3 in breast cancer biogenesis. Oncogene 2008; 27:3912-22. [PMID: 18264132 DOI: 10.1038/onc.2008.33] [Citation(s) in RCA: 173] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Benzo[a]pyrene diol epoxide (BPDE), the active metabolite of benzo[a]pyrene present in tobacco smoke, is a major cancer-causing compound. To evaluate the effects of BPDE on human breast epithelial cells, we exposed an immortalized human breast cell line, MCF 10A, to BPDE and characterized the gene expression pattern. Of the differential genes expressed, we found consistent activation of DDX3, a member of the DEAD box RNA helicase family. Overexpression of DDX3 in MCF 10A cells induced an epithelial-mesenchymal-like transformation, exhibited increased motility and invasive properties, and formed colonies in soft-agar assays. Besides the altered phenotype, MCF 10A-DDX3 cells repressed E-cadherin expression as demonstrated by both immunoblots and by E-cadherin promoter-reporter assays. In addition, an in vivo association of DDX3 and the E-cadherin promoter was demonstrated by chromatin immunoprecipitation assays. Collectively, these results demonstrate that the activation of DDX3 by BPDE, can promote growth, proliferation and neoplastic transformation of breast epithelial cells.
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Research Support, Non-U.S. Gov't |
17 |
173 |
5
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Vesuna F, Lisok A, Kimble B, Domek J, Kato Y, van der Groep P, Artemov D, Kowalski J, Carraway H, van Diest P, Raman V. Twist contributes to hormone resistance in breast cancer by downregulating estrogen receptor-α. Oncogene 2012; 31:3223-34. [PMID: 22056872 PMCID: PMC3276743 DOI: 10.1038/onc.2011.483] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Revised: 09/14/2011] [Accepted: 09/15/2011] [Indexed: 11/30/2022]
Abstract
The role of estrogen receptor-α (ER) in breast cancer development, and as a primary clinical marker for breast cancer prognosis, has been well documented. In this study, we identified the oncogenic protein, TWIST1 (Twist), which is overexpressed in high-grade breast cancers, as a potential negative regulator of ER expression. Functional characterization of ER regulation by Twist was performed using Twist low (MCF-7, T-47D) and Twist high (Hs 578T, MDA-MB-231, MCF-7/Twist) expressing cell lines. All Twist high expressing cell lines exhibited low ER transcript and protein levels. By chromatin immunoprecipitation and promoter assays, we demonstrated that Twist could directly bind to E-boxes in the ER promoter and significantly downregulate ER promoter activity in vitro. Functionally, Twist overexpression caused estrogen-independent proliferation of breast cells, and promoted hormone resistance to the selective estrogen receptor modulator tamoxifen and selective estrogen receptor down-regulator fulvestrant. Importantly, this effect was reversible on downregulating Twist. In addition, orthotopic tumors generated in mice using MCF-7/Twist cells were resistant to tamoxifen. These tumors had high vascular volume and permeability surface area, as determined by magnetic resonance imaging (MRI). Mechanistically, Twist recruited DNA methyltransferase 3B (DNMT3B) to the ER promoter, leading to a significantly higher degree of ER promoter methylation compared with parental cells. Furthermore, we demonstrated by co-immunoprecipitation that Twist interacted with histone deacetylase 1 (HDAC1) at the ER promoter, causing histone deacetylation and chromatin condensation, further reducing ER transcript levels. Functional re-expression of ER was achieved using the demethylating agent, 5-azacytidine, and the HDAC inhibitor, valproic acid. Finally, an inverse relationship was observed between Twist and ER expression in human breast tumors. In summary, the regulation of ER by Twist could be an underlying mechanism for the loss of ER activity observed in breast tumors, and may contribute to the generation of hormone-resistant, ER-negative breast cancer.
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Research Support, N.I.H., Extramural |
13 |
125 |
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Gort EH, van Haaften G, Verlaan I, Groot AJ, Plasterk RHA, Shvarts A, Suijkerbuijk KPM, van Laar T, van der Wall E, Raman V, van Diest PJ, Tijsterman M, Vooijs M. The TWIST1 oncogene is a direct target of hypoxia-inducible factor-2alpha. Oncogene 2007; 27:1501-10. [PMID: 17873906 DOI: 10.1038/sj.onc.1210795] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Hypoxia-inducible factors (HIFs) are highly conserved transcription factors that play a crucial role in oxygen homeostasis. Intratumoral hypoxia and genetic alterations lead to HIF activity, which is a hallmark of solid cancer and is associated with poor clinical outcome. HIF activity is regulated by an evolutionary conserved mechanism involving oxygen-dependent HIFalpha protein degradation. To identify novel components of the HIF pathway, we performed a genome-wide RNA interference screen in Caenorhabditis elegans, to suppress HIF-dependent phenotypes, like egg-laying defects and hypoxia survival. In addition to hif-1 (HIFalpha) and aha-1 (HIFbeta), we identified hlh-8, gska-3 and spe-8. The hlh-8 gene is homologous to the human oncogene TWIST1. We show that TWIST1 expression in human cancer cells is enhanced by hypoxia in a HIF-2alpha-dependent manner. Furthermore, intronic hypoxia response elements of TWIST1 are regulated by HIF-2alpha, but not HIF-1alpha. These results identify TWIST1 as a direct target gene of HIF-2alpha, which may provide insight into the acquired metastatic capacity of hypoxic tumors.
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Research Support, Non-U.S. Gov't |
18 |
114 |
7
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Karthega M, Raman V, Rajendran N. Influence of potential on the electrochemical behaviour of beta titanium alloys in Hank's solution. Acta Biomater 2007; 3:1019-23. [PMID: 17478134 DOI: 10.1016/j.actbio.2007.02.009] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2006] [Revised: 02/12/2007] [Accepted: 02/14/2007] [Indexed: 11/21/2022]
Abstract
The electrochemical behaviour of beta titanium alloys, namely Ti-15Mo (TiMo) and Ti-29Nb-13Ta-4.6Zr (TNTZ), were studied under physiological conditions using open circuit potential (OCP), potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) measurements. The OCP data for TNTZ alloy indicated a noble behaviour compared to TiMo alloy. The current density value for TNTZ alloy calculated from polarization measurement was found to be comparable to that of TiMo. The EIS technique was applied to study the nature of the passive film formed on binary TiMo alloy at various impressed potentials and the results were compared with that of the quaternary TNTZ alloy. The EIS spectra obtained for TiMo alloy exhibited a single time constant for all potentials, indicating a highly compact passive layer over the surface. The TNTZ alloy, however, exhibited a single time constant at lower potentials and two time constants at higher potentials, indicating a bilayer structure at higher potentials.
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102 |
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Matava CT, Kovatsis PG, Summers JL, Castro P, Denning S, Yu J, Lockman JL, Von Ungern-Sternberg B, Sabato S, Lee LK, Ayad I, Mireles S, Lardner D, Whyte S, Szolnoki J, Jagannathan N, Thompson N, Stein ML, Dalesio N, Greenberg R, McCloskey J, Peyton J, Evans F, Haydar B, Reynolds P, Chiao F, Taicher B, Templeton T, Bhalla T, Raman VT, Garcia-Marcinkiewicz A, Gálvez J, Tan J, Rehman M, Crockett C, Olomu P, Szmuk P, Glover C, Matuszczak M, Galvez I, Hunyady A, Polaner D, Gooden C, Hsu G, Gumaney H, Pérez-Pradilla C, Kiss EE, Theroux MC, Lau J, Asaf S, Ingelmo P, Engelhardt T, Hervías M, Greenwood E, Javia L, Disma N, Yaster M, Fiadjoe JE. Pediatric Airway Management in COVID-19 Patients: Consensus Guidelines From the Society for Pediatric Anesthesia's Pediatric Difficult Intubation Collaborative and the Canadian Pediatric Anesthesia Society. Anesth Analg 2020; 131:61-73. [PMID: 32287142 PMCID: PMC7173403 DOI: 10.1213/ane.0000000000004872] [Citation(s) in RCA: 98] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/10/2020] [Indexed: 12/14/2022]
Abstract
The severe acute respiratory syndrome coronavirus 2 (coronavirus disease 2019 [COVID-19]) pandemic has challenged medical systems and clinicians globally to unforeseen levels. Rapid spread of COVID-19 has forced clinicians to care for patients with a highly contagious disease without evidence-based guidelines. Using a virtual modified nominal group technique, the Pediatric Difficult Intubation Collaborative (PeDI-C), which currently includes 35 hospitals from 6 countries, generated consensus guidelines on airway management in pediatric anesthesia based on expert opinion and early data about the disease. PeDI-C identified overarching goals during care, including minimizing aerosolized respiratory secretions, minimizing the number of clinicians in contact with a patient, and recognizing that undiagnosed asymptomatic patients may shed the virus and infect health care workers. Recommendations include administering anxiolytic medications, intravenous anesthetic inductions, tracheal intubation using video laryngoscopes and cuffed tracheal tubes, use of in-line suction catheters, and modifying workflow to recover patients from anesthesia in the operating room. Importantly, PeDI-C recommends that anesthesiologists consider using appropriate personal protective equipment when performing aerosol-generating medical procedures in asymptomatic children, in addition to known or suspected children with COVID-19. Airway procedures should be done in negative pressure rooms when available. Adequate time should be allowed for operating room cleaning and air filtration between surgical cases. Research using rigorous study designs is urgently needed to inform safe practices during the COVID-19 pandemic. Until further information is available, PeDI-C advises that clinicians consider these guidelines to enhance the safety of health care workers during airway management when performing aerosol-generating medical procedures. These guidelines have been endorsed by the Society for Pediatric Anesthesia and the Canadian Pediatric Anesthesia Society.
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Guideline |
5 |
98 |
9
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Raman V, Tamori A, Vali M, Zeller K, Korz D, Sukumar S. HOXA5 regulates expression of the progesterone receptor. J Biol Chem 2000; 275:26551-26555. [PMID: 10875927 DOI: 10.1074/jbc.c000324200] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The majority of breast carcinomas show reduced or no expression of the transcription factor, HOXA5. Recently, we have shown that HOXA5 is a potent transactivator of p53 in breast cells and thus may affect the response of breast cancer cells to DNA damage. To determine whether HOXA5 played a role in growth and homeostasis in breast cells, we studied its interaction with the progesterone receptor. The progesterone receptor (PR) belongs to the superfamily of nuclear receptors whose members co-ordinate morphogenesis of the mammary gland in response to binding to their cognate ligands. An increased expression of the endogenous PR gene was seen in MCF-7 cells following induced expression of an exogenously transfected HOXA5 gene. HOXA5, but not HOXB4, -B5, or -B7 activated the PR promoter in two breast cancer cell lines, MCF-7 and Hs578T. Deletion and mutation analysis of the promoter identified a single HOXA5-binding site required for transactivation of the PR gene by HOXA5. HOXA5 binds directly to this site in the PR promoter. Thus, HOXA5 may behave as a transcriptional regulator of multiple target genes, two among which are p53 and the progesterone receptor.
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25 |
65 |
10
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Raman V, Clary R, Siegrist KL, Zehnbauer B, Chatila TA. Increased prevalence of mutations in the cystic fibrosis transmembrane conductance regulator in children with chronic rhinosinusitis. Pediatrics 2002; 109:E13. [PMID: 11773581 DOI: 10.1542/peds.109.1.e13] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Chronic rhinosinusitis results in significant morbidity in the pediatric population; however, no predisposing factor is found in many cases. Cystic fibrosis (CF) is a recognized cause of chronic rhinosinusitis. Although the carrier frequency for CF ranges from 3% to 4% in the general white population, the prevalence of mutations in the CF transmembrane conductance regulator (CFTR) among children with chronic rhinosinusitis is unknown. Our objective was to study the frequency of CFTR mutations among children with chronic rhinosinusitis. METHODS Fifty-eight white children who were from the St Louis metropolitan area and had chronic rhinosinusitis, none of whom satisfied diagnostic criteria for CF, underwent sweat testing and genotyping for CFTR mutations using an assay that detects 90% of mutations seen in this ethnic group. RESULTS Seven of the 58 patients (12.1%) tested harbored CFTR mutations as compared with the expected rate of 3% to 4% in this ethnic group. Five patients had the DeltaF508, 1 had the R117H, and 1 had the I148T mutation. Only 1 of the 7 children had a borderline abnormal sweat test. Two of the 58 patients experienced recurrent Pseudomonas aeruginosa rhinosinusitis, and both were DeltaF508 heterozygotes. Three other children with no detectable CFTR mutation had borderline elevated sweat-test results. The CFTR intron 8 5T polymorphism was found at a frequency comparable to that reported for the general population. CONCLUSION There is an increased occurrence of CFTR mutations in children who have chronic rhinosinusitis and do not meet diagnostic criteria for CF, usually in the setting of a normal sweat chloride. These results suggest a role for CFTR mutations in predisposition to chronic rhinosinusitis.
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Ramlogan S, Raman V, Sweet J. A comparison of two forms of teaching instruction: video vs. live lecture for education in clinical periodontology. EUROPEAN JOURNAL OF DENTAL EDUCATION : OFFICIAL JOURNAL OF THE ASSOCIATION FOR DENTAL EDUCATION IN EUROPE 2014; 18:31-8. [PMID: 24423173 DOI: 10.1111/eje.12053] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/22/2013] [Indexed: 05/12/2023]
Abstract
INTRODUCTION This crossover controlled study aimed to compare the knowledge and skill attained by third-year dental students in three clinical exercises in the discipline of periodontology through video and live lecture instruction. METHODS Students (n = 35) segregated into two group either viewed a video or attended a live lecture repeated over three clinical teaching sessions. Pre-test and post-test written assessments were completed and comparisons between video and live lecture done (analysis of variance, P < 0.05). Students were assessed on clinic by a simple checklist. A questionnaire was administered after all three sessions to determine preferences and opinions on video and live lecture. RESULTS For the combined three sessions, both video (n = 48) and live lecture (n = 47) groups attained similar mean pre-test scores. The mean post-test score was statistically significantly greater (P = 0.049) for the live lecture (74.9%, SD 14.9) compared to the video group (68.6%, SD 16.3). All students attained clinical proficiency via the simple checklist. In adding to their clinical skill, more students favoured video (97%) vs. live lecture (78.8%). Most students (97%) favoured a future combination of video and lecture. DISCUSSION While students were deemed clinically competent via a simple checklist, the live lecture group performed better than the video group via the in-depth post-test assessment. Students had a preference for video and would like it integrated in the lecture rather than act as a substitute for the lecture. CONCLUSION The use of video alone in clinical periodontology training may have limitations unless supplemented by appropriate learning activities.
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Comparative Study |
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Raman V, Kim J, Sharkey A, Chatila T. Response of refractory Kawasaki disease to pulse steroid and cyclosporin A therapy. Pediatr Infect Dis J 2001; 20:635-7. [PMID: 11419513 DOI: 10.1097/00006454-200106000-00022] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We describe a child with aggressive and protracted Kawasaki disease with coronary aneurysms, myocarditis, pericarditis and valvular insufficiency, despite repeated administration of intravenous immunoglobulin. After a transient response to pulse corticosteroids, his disease ultimately subsided with combination therapy with pulse and high dosage corticosteroids and cyclosporin A. Aggressive immunosuppressive therapy with high dosage corticosteroids and cyclosporin A may be beneficial in patients with refractory Kawasaki disease.
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Case Reports |
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48 |
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Wilky BA, Kim C, McCarty G, Montgomery EA, Kammers K, DeVine LR, Cole RN, Raman V, Loeb DM. RNA helicase DDX3: a novel therapeutic target in Ewing sarcoma. Oncogene 2015; 35:2574-83. [PMID: 26364611 DOI: 10.1038/onc.2015.336] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 06/29/2015] [Accepted: 08/03/2015] [Indexed: 02/08/2023]
Abstract
RNA helicase DDX3 has oncogenic activity in breast and lung cancers and is required for translation of complex mRNA transcripts, including those encoding key cell-cycle regulatory proteins. We sought to determine the expression and function of DDX3 in sarcoma cells, and to investigate the antitumor activity of a novel small molecule DDX3 inhibitor, RK-33. Utilizing various sarcoma cell lines, xenografts and human tissue microarrays, we measured DDX3 expression at the mRNA and protein levels, and evaluated cytotoxicity of RK-33 in sarcoma cell lines. To study the role of DDX3 in Ewing sarcoma, we generated stable DDX3-knockdown Ewing sarcoma cell lines using DDX3-specific small hairpin RNA (shRNA), and assessed oncogenic activity. DDX3-knockdown and RK-33-treated Ewing sarcoma cells were compared with wild-type cells using an isobaric mass-tag quantitative proteomics approach to identify target proteins impacted by DDX3 inhibition. Overall, we found high expression of DDX3 in numerous human sarcoma subtypes compared with non-malignant mesenchymal cells, and knockdown of DDX3 by RNA interference inhibited oncogenic activity in Ewing sarcoma cells. Treatment with RK-33 was preferentially cytotoxic to sarcoma cells, including chemotherapy-resistant Ewing sarcoma stem cells, while sparing non-malignant cells. Sensitivity to RK-33 correlated with DDX3 protein expression. Growth of human Ewing sarcoma xenografts expressing high DDX3 was inhibited by RK-33 treatment in mice, without overt toxicity. DDX3 inhibition altered the Ewing sarcoma cellular proteome, especially proteins involved in DNA replication, mRNA translation and proteasome function. These data support further investigation of the role of DDX3 in sarcomas, advancement of RK-33 to Ewing sarcoma clinical trials and development of RNA helicase inhibition as a novel anti-neoplastic strategy.
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Research Support, N.I.H., Extramural |
10 |
44 |
14
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Blaeser F, Bryce PJ, Ho N, Raman V, Dedeoglu F, Donaldson DD, Geha RS, Oettgen HC, Chatila TA. Targeted inactivation of the IL-4 receptor alpha chain I4R motif promotes allergic airway inflammation. ACTA ACUST UNITED AC 2003; 198:1189-200. [PMID: 14557412 PMCID: PMC2194235 DOI: 10.1084/jem.20030471] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The insulin/interleukin-4 (IL-4) receptor (I4R) motif mediates the association of insulin receptor substrate (IRS)-2 with the interleukin-4 (IL-4)Ralpha chain and transduces mitogenic signals in response to IL-4. Its physiological functions were analyzed in mice with a germline point mutation that changed the motif's effector tyrosine residue into phenylalanine (Y500F). The Y500F mutation abrogated IRS-2 phosphorylation and impaired IL-4-induced CD4+ T lymphocyte proliferation but left unperturbed Stat6 activation, up-regulation of IL-4-responsive gene products, and Th cell differentiation under Th2 polarizing conditions. However, in vivo the Y500F mutation was associated with increased allergen-induced IgE production, airway responsiveness, tissue eosinophilia, and mucus production. These results define an important role for the I4R motif in regulating allergic inflammation.
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Research Support, U.S. Gov't, P.H.S. |
22 |
41 |
15
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Darr JA, Guo ZX, Raman V, Bououdina M, Rehman IU. Metal organic chemical vapour deposition (MOCVD) of bone mineral like carbonated hydroxyapatite coatingsElectronic supplementary information (ESI) available: experimental data. See http://www.rsc.org/suppdata/cc/b3/b312855p/. Chem Commun (Camb) 2004:696-7. [PMID: 15010786 DOI: 10.1039/b312855p] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
For the first time, the MOCVD technique has been used to deposit carbonated hydroxyapatite onto Ti6AL4V substrates using volatile monomeric (liquid) complexes [Ca(beta-diketonate)(2)(L)] and P(OEt)(3).
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Abstract
Homeobox-containing genes play a major role in the control of segmental identity during embryonic development in Drosophila. Abnormalities of these genes have been shown to produce a wide variety of congenital anomalies in invertebrates and in vertebrates. Many transgenic mice, which are mutant for homeobox genes, show a specific skeletal abnormality, similar to the human cervical rib. In humans, a relationship exists between malformations and tumours. Human cervical rib has been shown to be associated with an increased incidence of malignancy. Recent evidence indicates that homeobox genes might also play a role in carcinogenesis. In this article, we explore the possibility that alterations of homeobox genes might be the basic underlying aetiology for the association between congenital malformations and tumours, at least in a proportion of cases. We provide evidence in support of this argument and suggest areas of further research which would confirm this concept.
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Abstract
BACKGROUND What is the molecular basis of the osteotrophic action of prostatic metastases? Demineralized bone matrix has the potential to induce new bone formation. The identification of bone morphogenetic proteins (BMPs) as the primary inducers of new bone formation in demineralized bone matrix has set the stage for studying prostate cancer-bone interrelationships. We have hypothesized that BMPs may be expressed in prostate and may be involved in the osteotrophic actions of metastatic prostate cancer cells. METHODS Using polymerase chain reaction (PCR)-based quantitation, this study examined the presence of BMPs in mouse prostate and their potential regulation by orchidectomy and androgen replacement. RESULTS BMP-7 and BMP-4 genes were expressed in mouse prostate. Quantitative PCR analysis showed that the BMP-7 mRNA level was significantly decreased following orchidectomy and increased by testosterone and dihydrotestosterone. Therefore, the BMP-7 mRNA level is androgen-dependent. On the other hand, BMP-4 was expressed constitutively in the prostate. CONCLUSIONS The regulated expression of BMP-7 mRNA in the prostate suggests that BMP-7 may explain in part the stimulation of bone formation and osteosclerosis by metastatic prostate adenocarcinoma.
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Raman VT, Splaingard M, Tumin D, Rice J, Jatana KR, Tobias JD. Utility of screening questionnaire, obesity, neck circumference, and sleep polysomnography to predict sleep-disordered breathing in children and adolescents. Paediatr Anaesth 2016; 26:655-64. [PMID: 27111886 DOI: 10.1111/pan.12911] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/23/2016] [Indexed: 11/26/2022]
Abstract
BACKGROUND Polysomnography (PSG) remains the gold standard for diagnosing obstructive sleep apnea (OSA) and sleep-disordered breathing in children. Yet, simple screening tools are needed as it is not feasible to perform PSG in all patients with possible OSA. AIM The study adapted questions from the Pediatric Sleep Questionnaire-Sleep-Related Breathing Disorder (SRBD) Questionnaire to develop a predictive scale for OSA identified on PSG. We also tested whether adding anthropometric measurements (body mass index and neck circumference) improved prediction of OSA. METHODS After IRB approval, OSA questionnaires and anthropometric measurements were collected on 948 consecutive patients scheduled for PSG, aged 4 months to 24.5 years (median = 8.5 years). The sample was reduced to 636 patients in the age range (6-18 years old) where normative values for neck circumference are defined. OSA was characterized using the obstructive apnea-hypopnea index (AHI). After identifying questions related to OSA in univariate logistic regression, multivariable models were fitted to select questions for a short scale, and points for exceeding body mass or neck circumference cutoffs were added to assess improvement in predictive value. RESULTS A long scale of 16 questionnaire items was constructed using univariate models, while six items were selected for the short scale by multivariable regression. The short scale was associated with greater odds of moderate/severe OSA (OR = 1.964; 95% CI = 1.620, 2.381; P < 0.001) and attained good predictive value (area under receiver operating characteristics curve [AUC] = 0.74), which was not significantly improved by addition of BMI and neck circumference data (AUC = 0.75). CONCLUSIONS We developed a six-question scale with good predictive utility for OSA. These findings may contribute to developing a preoperative clinical tool to help clinicians identify children with OSA for determining risk stratification and postoperative disposition.
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Leonce J, Brockton N, Robinson S, Venkatesan S, Bannister P, Raman V, Murphy K, Parker K, Pavitt D, Teoh TG, Regan L, Burchell A, Steer P, Johnston DG. Glucose Production in the Human Placenta. Placenta 2006; 27 Suppl A:S103-8. [PMID: 16618444 DOI: 10.1016/j.placenta.2006.02.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Revised: 02/04/2006] [Accepted: 02/07/2006] [Indexed: 11/26/2022]
Abstract
Glucose transfer from mother to fetus by placental facilitated diffusion is the dominant mechanism by which the fetus acquires glucose. In small for gestational age pregnancies, fetal glucose concentrations tend to be lower than normal and this persists following delivery. GLUT1 is the major glucose transporter in human placenta but there is no evidence of GLUT1 deficiency as a cause of the lower fetal glucose concentration in small for gestational age pregnancy. The physiological and pathological roles of the other glucose transporters (and there are 14 currently described) are unknown. In recent years, the possibility has been raised that the placenta is itself capable of supplying glucose for fetal needs. This hypothesis derived from glucose isotope studies in normal pregnancy, where dilution of glucose isotope was demonstrated in blood samples taken from the fetal circulation during intravenous infusion of glucose isotope in the mother. Although other gluconeogenic enzymes were known to be present, the placenta was previously considered incapable of glucose secretion because it lacked functional glucose-6-phosphatase. Recent studies, however, have suggested that specific glucose-6-phosphatase may be present in placenta but it may be the product of a different gene from conventional hepatic glucose-6-phosphatase. The presence of the specific transporters necessary for glucose-6-phosphatase activity is currently being investigated. The role of placental glucose secretion in normal and growth-restricted pregnancies is an area of current study.
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Raman V, Blaeser F, Ho N, Engle DL, Williams CB, Chatila TA. Requirement for Ca2+/calmodulin-dependent kinase type IV/Gr in setting the thymocyte selection threshold. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:6270-8. [PMID: 11714790 DOI: 10.4049/jimmunol.167.11.6270] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The outcome of thymocyte selection is influenced by the nature of Ca2+ signals transduced by the TCR. Robust Ca2+ responses characterize high-affinity, negatively selecting peptide/TCR interactions, while modest responses typify lower-affinity, positively selecting interactions. To elucidate mechanisms by which thymocytes decode distinct Ca2+ signals, we examined selection events in mice lacking Ca2+/calmodulin-dependent protein kinase type IV/Gr (CaMKIV/Gr), which is enriched in thymocytes. CaMKIV/Gr-deficient thymocytes exhibited impaired positive selection and defective Ca2+-dependent gene transcription. Significantly, CaMKIV/Gr deficiency raised the selection threshold of peptide/TCR interactions such that a peptide that normally induced weak negative selection instead promoted positive selection. These results demonstrate an important role for CaMKIV/Gr in sensitizing thymocytes to selection by low-affinity peptides.
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Saadat H, Bissonnette B, Tumin D, Raman V, Rice J, Barry N, Tobias J. Effects of partial sleep deprivation on reaction time in anesthesiologists. Paediatr Anaesth 2017; 27:358-362. [PMID: 27900800 DOI: 10.1111/pan.13035] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/11/2016] [Indexed: 12/21/2022]
Abstract
BACKGROUND Fatigue in anesthesiologists may have implications that extend beyond individual well-being. AIM The aim of the present study was to evaluate the impact of sleep deprivation on the reaction time in anesthesiologists either after an overnight call or regular working hours. Moderation of this effect by coping strategies was observed. METHODS Psychomotor vigilance test was used to assess reaction time in 23 anesthesiologists at two time-points: (i) on a regular non-call day and (ii) after a 17-h in-house call. Student's paired t-test was used to compare Psychomotor Vigilance Task data at these two moments. Change score regression was performed to determine the association between coping strategies, assessed using the Coping Strategy Indicator instrument, and decline in reaction time after night call. RESULTS Twenty-one colleagues completed the psychomotor vigilance test measurements after two decided to end their participation for personal reasons. Post-call psychomotor vigilance test mean reaction time decreased by an average of 31.2 ms (95% CI: 0.5, 61.9; P = 0.047) when compared to regular day. Reliance on specific coping mechanisms, indicated by Coping Strategy Indicator scale scores, included problem-solving (28 ± 4), followed by seeking social support (23 ± 5) and avoidance (19 ± 4). The change score regression model (r2 = 0.48) found that greater reliance on avoidance was associated with greater increase in reaction time after night call. CONCLUSION Reaction time increased considerably in anesthesiologists after a night call duty. Greater subjective reliance on avoidance as a coping strategy was associated with greater deterioration in performance.
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Miller R, Tumin D, Hayes D, Uffman JC, Raman VT, Tobias JD. Unmet Need for Care Coordination Among Children with Special Health Care Needs. Popul Health Manag 2018; 22:255-261. [PMID: 30272532 DOI: 10.1089/pop.2018.0094] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Socioeconomic disparities in access to care coordination have been noted among children with special health care needs (CSHCN). Following recent policy developments and technological innovation, care coordination has become more widespread, possibly leading to reduced disparity in care coordination access. This study investigates whether child and household characteristics remain associated with unmet need for care coordination among CSHCN. CSHCN (aged <18 years) requiring ≥2 types of health services in the past year were identified in the 2016 National Survey of Children's Health (NSCH). Care coordination was defined as help with arranging the child's care among different doctors or services. Children were classified as not needing care coordination, receiving sufficient care coordination (met need), or needing but not receiving care coordination (unmet need). Weighted multinomial logistic regression examined the association of child characteristics with this outcome. The analysis included 5622 children with no need for care coordination, 1466 with a met need, and 980 with unmet needs. Children with mental health conditions were more likely to have unmet rather than met needs for care coordination (odds ratio = 4.1; 95% confidence interval: 2.7, 6.1; P < 0.001). After multivariable adjustment, race/ethnicity, income, family structure, insurance coverage, place of birth, and use of English in the home were not associated with having unmet rather than met needs for care coordination. Among CSHCN, the latest data from NSCH reveal no evidence of previously described socioeconomic disparities in access to care coordination. Nevertheless, unmet needs for care coordination remain prevalent, especially among children with mental health conditions.
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Raman V, Tobias JD, Bryant J, Rice J, Jatana K, Merz M, Elmaraghy C, Kang DR. Effect of cuffed and uncuffed endotracheal tubes on the oropharyngeal oxygen and volatile anesthetic agent concentration in children. Int J Pediatr Otorhinolaryngol 2012; 76:842-4. [PMID: 22444738 DOI: 10.1016/j.ijporl.2012.02.055] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 02/15/2012] [Accepted: 02/17/2012] [Indexed: 12/30/2022]
Abstract
BACKGROUND Over the past 5 years, there has been a change in the clinical practice of pediatric anesthesiology with a transition to the use of cuffed instead of uncuffed endotracheal tubes (ETTs) in infants and children. As the trachea is sealed, one advantage is to eliminate the contamination of the oropharynx with oxygen which should be advantageous during adenotonsillectomy where there is a risk of airway fire. The current study prospectively assesses the oropharyngeal oxygen and volatile anesthetic agent concentration during adenotonsillectomy in infants and children. METHODS Following the induction of general anesthesia in patients scheduled for adenoidectomy, tonsillectomy or adenotonsillectomy, the trachea was intubated. The use of a cuffed or uncuffed ETT and the use of spontaneous (SV) or positive pressure ventilation (PPV) were at the discretion of the anesthesia team. The oxygen concentration was kept at 100% oxygen until the study was completed. Following placement of the mouth gag, the otolaryngolist placed into the oropharynx a small bore catheter, which was attached to a standard anesthesia gas monitoring device which sampled the gas at 150mL/min. The concentration of the oxygen and the concentration of the anesthetic agent in the oropharynx were measured for 5 breaths. RESULTS The cohort for the study included 200 patients ranging in age from 1 to 18 years. With the use of a cuffed ETT and either SV or PPV, the oxygen concentration in the oropharynx was 20-21% and the volatile agent concentration was 0% in all 118 patients. With the use of an uncuffed ETT and the administration of 100% oxygen, there was significant contamination of the oropharynx noted during both PPV and SV. The mean oxygen concentration was 71% during PPV with an uncuffed ETT and 65% during SV with an uncuffed ETT. In these patients, the oropharyngeal oxygenation concentration exceeded 30% in 73 of the 82 patients (89%). The oropharyngeal oxygen and agent concentration was greater when the leak around the uncuffed ETT was ≥10cmH(2)O versus less than 10cmH(2)O and when the leak around the uncuffed ETT was ≥15cmH(2)O versus less than 15cmH(2)O. CONCLUSIONS With the use of an uncuffed ETT and the administration of 100% oxygen, there was significant contamination of the oropharynx noted during both PPV and SV. The oropharyngeal concentration of oxygen is high enough to support combustion in the majority of patients. The use of a cuffed ETT eliminates oropharyngeal contamination with oxygen during the administration of anesthesia and may be useful in limiting the incidence of an airway fire.
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Heerma van Voss MR, van Kempen PMW, Noorlag R, van Diest PJ, Willems SM, Raman V. DDX3 has divergent roles in head and neck squamous cell carcinomas in smoking versus non-smoking patients. Oral Dis 2015; 21:270-1. [PMID: 25406365 DOI: 10.1111/odi.12299] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Raman VT, Tumin D, Uffman J, Thung AK, Burrier C, Jatana KR, Elmaraghy C, Tobias JD. Implementation of a perioperative surgical home protocol for pediatric patients presenting for adenoidectomy. Int J Pediatr Otorhinolaryngol 2017; 101:215-222. [PMID: 28964298 DOI: 10.1016/j.ijporl.2017.08.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 08/16/2017] [Accepted: 08/17/2017] [Indexed: 10/19/2022]
Abstract
INTRODUCTION The perioperative surgical home (PSH) is a patient-centered model designed to improve health, streamline the delivery of health care, and reduce the cost of care. Following the national introduction of PSH in 2014 by the ASA, adult hospitals have reported success with this model, with studies validating the benefits of PSH including reducing length of stay, lowering costs, and improving patient satisfaction. METHODS Eligible patients, ranging in age from 16-35 months of age, were identified by the pre-admission testing (PAT) registered nurses (RNs) and faculty anesthesiologists upon review of the patient history. Participation in Pediatric PSH (PPSH) was introduced to the families by the pediatric otolaryngologists. Either the patient's family or physician team could elect to decline participation in the PPSH model. On the day of surgery, the PPSH protocol included a paper checklist to ensure that all patients met eligibility standards. A standardized order-set was implemented in the electronic medical record (EMR) for pre-operative and post-operative nursing instructions and eligible medications. Patients received at least 3 hours of postoperative monitoring prior to discharge home to address postoperative issues. Prior to discharge, caregivers watched a standard teaching video, available on YouTube, which was developed in conjunction with the hospital educational and technical support staff. An attending anesthesiologist made a postoperative followup phone call on the evening of surgery to ensure no untoward events were experienced by the patient as well as elicit caregiver feedback concerning the discharge process. The protocol was discontinued if at any time family members, physicians, or nurses were uncomfortable with completing the protocol or felt that the patient did not meet discharge criteria. RESULTS One hundred sixty-six patients were evaluated for PPSH inclusion. Forty patients were excluded (23 did not meet inclusion criteria, 5 had viral upper respiratory infections, and 10 for other non specified reasons such as tonsillectomy added, sibling with surgery, and incorrect documentation). Therefore, a total of 126 were eligible for PPSH (male/female = 69/57; age 22 ± 4 months). The comparison group included 1,029 children (male/female = 645/384; age 22 ± 7 months of age) undergoing adenoidectomy who were not evaluated for PPSH inclusion. Of the 126 PPSH participants included in the analysis, 27 were excluded at some point during the pathway. Nine cases experienced oxygen desaturation, laryngospasm, or required supplemental oxygen. Noncompliance with the protocol was noted in 5 cases, parental concerns were noted in 17 cases, and there were concerns from the pediatric anesthesiologist or otolaryngologist in 5 cases. In the comparison group, hospital length of stay was significantly longer than in the PSH group (p<0.001), with 524 (51%) patients discharged on the day of service compared to 99 (79%) in the PSH group. No major morbidity or mortality occurred. There was no difference between the two groups in return to the emergency department (ED) visits within 30 days (PSH: 7/126, 6%; control: 59/1,029, 6%; p=0.935). Within 14 days of the procedure, 4 PPSH patients visited urgent care or a primary care physician; 4 visited the ED; and 1 was readmitted to the hospital. Twenty families contacted the otorhinolaryngology triage phone line primarily related to pain and fever. CONCLUSION We present our experience and success in developing a PPSH for patients, ranging in age from 16 to 35 months of age, undergoing adenoidectomy either alone or with tympanostomy tube insertion by protocolizing care, collaborating among care providers, and educating families. With this process in place, a significant percentage of these patients who were previously admitted were discharged home the same day of surgery.
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