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2.
JAMA Otolaryngol Head Neck Surg ; 141(6): 543-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25855885

RESUMO

IMPORTANCE: The PIK3CA mutation is one of the most common mutations in head and neck squamous cell carcinoma (HNSCC). Through this research we attempt to elicit the role of oncogene dependence and effects of targeted therapy on this PIK3CA mutation. OBJECTIVES: (1) To determine the role of oncogene dependence on PIK3CA-one of the more common and targetable oncogenes in HNSCC, and (2) to evaluate the consequence of this oncogene on the effectiveness of newly developed targeted therapies. DESIGN, SETTING, AND PARTICIPANTS: This was a cell culture-based, in vitro study performed at an academic research laboratory assessing the viability of PIK3CA-mutated head and neck cell lines when treated with targeted therapy. EXPOSURES: PIK3CA-mutated head and neck cell lines were treated with 17-AAG, GDC-0941, trametinib, and BEZ-235. MAIN OUTCOMES AND MEASURES: Assessment of cell viability of HNSCC cell lines characterized for PIK3CA mutations or SCC25 cells engineered to express the PIK3CA hotspot mutations E545K or H1047R. RESULTS: Surprisingly, in engineered cell lines, the hotspot E545K and H1047R mutations conferred increased, rather than reduced, IC50 assay measurements when treated with the respective HSP90, PI3K, and MEK inhibitors, 17-AAG, GDC-0941, and trametinib, compared with the SCC25 control cell lines. When treated with BEZ-235, H1047R-expressing cell lines showed increased sensitivity to inhibition compared with control, whereas those expressing E545K showed slightly increased sensitivity of unclear significance. CONCLUSIONS AND RELEVANCE: (1) The PIK3CA mutations within our engineered cell model did not lead to enhanced oncogene-dependent cell death when treated with direct inhibition of the PI3K enzyme yet did show increased sensitivity compared with control with dual PI3K/mTOR inhibition. (2) Oncogene addiction to PIK3CA hotspot mutations, if it occurs, is likely to evolve in vivo in the context of additional molecular changes that remain to be identified. Additional study is required to develop new model systems and approaches to determine the role of targeted therapy in the treatment of PI3K-overactive HNSCC tumors.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Terapia de Alvo Molecular , Mutação , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/genética , Benzoquinonas/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Classe I de Fosfatidilinositol 3-Quinases , Humanos , Imidazóis/uso terapêutico , Indazóis/uso terapêutico , Concentração Inibidora 50 , Lactamas Macrocíclicas/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico , Quinolinas/uso terapêutico , Carcinoma de Células Escamosas de Cabeça e Pescoço , Sulfonamidas/uso terapêutico , Serina-Treonina Quinases TOR/antagonistas & inibidores , Células Tumorais Cultivadas
3.
Laryngoscope ; 124(4): 896-901, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24105798

RESUMO

OBJECTIVES/HYPOTHESIS: To better understand the causes and outcomes of lawsuits involving otolaryngologists in the past decade by analyzing malpractice litigation trends to prevent future litigation and improve physician education. STUDY DESIGN: Analysis of a national database for all US civil trials. METHODS: The Westlaw database was reviewed from 2001 to 2011. Data were compiled on the demographics of the plaintiffs, use of expert witnesses, procedures, nature of the injury, legal allegations, verdicts, and indemnities. RESULTS: One hundred ninety-eight cases met inclusion criteria. Verdicts for the defendant/otolaryngologist predominated (58%), whereas the average award when the verdict favored the plaintiff was $1,782,514. When otolaryngologists were used as expert witnesses by the defense, the verdict outcome statistically favored the defendant. Two of the most commonly cited legal allegations were improper performance and failure to diagnose and treat. Fifty-one cases involved allegations of wrongful death, with the overall outcome favoring the plaintiffs (51%). The average indemnities in these cases were significantly higher for plaintiff verdicts at $2,552,580 versus settlements at $992,896. Forty-two cases involved malignancy, with the two most common allegations being failure to diagnose and treat (79%) and delay in diagnosis (74%). CONCLUSIONS: Our study reveals that in the past decade, in significant malpractice litigations, overall outcomes favored otolaryngologists. The average awards was significantly higher when cases involved malignancy. Our analysis reveals the importance of meticulous surgical techniques and thorough preoperative evaluations. Last, when otolaryngologists are defendants in litigation, our review reiterates the value of the otolaryngologist as the defense's expert witnesses.


Assuntos
Competência Clínica , Imperícia/estatística & dados numéricos , Otolaringologia/legislação & jurisprudência , Médicos/legislação & jurisprudência , Humanos , Imperícia/legislação & jurisprudência , Otorrinolaringopatias/diagnóstico , Otorrinolaringopatias/terapia , Médicos/normas , Estudos Retrospectivos , Estados Unidos
5.
Otolaryngol Head Neck Surg ; 145(3): 476-81, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21572080

RESUMO

OBJECTIVE: Transforming growth factor-ß2 (TGF-ß2) is a principal cytokine of interest in the pathogenesis of scar formation and is a potential target for future molecular-based adjunctive therapies. The authors hypothesize that interfering RNA (RNAi) can be used to modulate TGF-ß2 production in cultured human respiratory fibroblasts. STUDY DESIGN: Basic science. Setting. Laboratory. SUBJECTS AND METHODS: RNAi constructs targeted to the TGF-ß2 transcript were complexed with microsomal lipids and applied to human fibroblasts in cell culture. Transfection efficiency and cell viability were measured by fluorescence microscopy. Messenger RNA (mRNA) for TGF-ß2 was measured 48 hours posttransfection using real-time quantitative PCR. The quantity of TGF-ß2 protein produced with increasing concentrations of RNAi was measured using enzyme-linked immunosorbent assay. The function of RNAi-treated fibroblasts was tested using a wound-healing assay. RESULTS: Transfection efficiency of more than 80% was achieved with minimal induced cell death. Treated cells showed selective knockdown of 80% of TGF-ß2 mRNA, which was confirmed with negative controls. As the concentration of RNAi was increased, an incremental decrease in TGF-ß2 protein was measured. CONCLUSION: RNAi technology is an effective means of localized and transient gene silencing in cultured human fibroblasts. Transfection can be achieved using microsome complexed RNAi with minimal induced cell death. This preliminary result shows promise for future in vitro studies.


Assuntos
Fibroblastos/metabolismo , Interferência de RNA , Transfecção , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Morte Celular/fisiologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Fibroblastos/citologia , Humanos , RNA Mensageiro/metabolismo , Padrões de Referência , Sistema Respiratório/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade
6.
Otolaryngol Head Neck Surg ; 142(3): 306-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20172371

RESUMO

OBJECTIVE: To evaluate the clinical efficacy of surgeon-performed, office-based head and neck ultrasound in facilitating diagnostic fine needle aspiration (FNA) of lesions in the head and neck. STUDY DESIGN: A randomized controlled trial of ultrasound-guided FNA versus traditional palpation-guided technique for palpable masses in the head and neck. SETTING: An office-based study performed in a military academic medical center. SUBJECTS AND METHODS: Eighty-one adults older than 18 years of age with a palpable head and neck mass (less than 3 cm in largest diameter) were randomized to ultrasound-guided or traditional palpation-guided FNA of a head and neck mass. Measured variables and outcomes for the study included tissue adequacy rates, tissue type, and operator variability. RESULTS: Following three passes using either palpation or ultrasound guidance, a comparative tissue adequacy rate of 84 percent for ultrasound guidance versus 58 percent for standard palpation was established (P < 0.014). With regard to tissue type, a statistically significant comparative diagnostic advantage for ultrasound guidance was observed in thyroid tissue while remaining statistically insignificant for lymphatic and salivary tissues. No statistical significance was found when comparing the ability of otolaryngology residents versus attending otolaryngologists to obtain ultrasound-guided diagnostic samples. CONCLUSION: Office-based surgeon-performed ultrasound-guided FNA of palpable lesions in the head and neck yields a statistically significant higher diagnostic rate compared to standard palpation technique. Our institutional experience supports the utility of surgeon-performed ultrasound as a core competency in clinical practice.


Assuntos
Biópsia por Agulha Fina/métodos , Neoplasias de Cabeça e Pescoço/patologia , Cirurgia Assistida por Computador , Adulto , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Ultrassonografia
7.
Laryngoscope ; 120(2): 259-60, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20013844

RESUMO

Struma ovarii, a rare germ cell tumor of the ovary composed of >50% thyroid tissue, is traditionally managed by gynecologic surgeons. Although struma ovarii is typically cured by simple excision, otolaryngology-head and neck surgeons may play a critical role in caring for these patients. In this article, we present two cases of struma ovarii and discuss the role of the otolaryngologist.


Assuntos
Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias Ovarianas/diagnóstico , Estruma Ovariano/diagnóstico , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Otolaringologia , Neoplasias Ovarianas/secundário , Neoplasias Ovarianas/cirurgia , Estruma Ovariano/cirurgia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia
8.
Blood Cells Mol Dis ; 43(2): 141-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19409822

RESUMO

One of the most commonly inherited anemias in man is Hereditary Spherocytosis (HS) with an incidence of 1 in 2000 for persons of Northern European descent. Mouse models of HS include spontaneous inherited hemolytic anemias and those generated by gene targeting. The Neonatal anemia (Nan) mouse is a novel model of HS generated by N-ethyl-N-nitrosurea mutagenesis and suffers from a severe neonatal anemia. Adult Nan mice have a lifelong hemolytic anemia with decreased red blood cell numbers, hematocrit, and hemoglobin, but elevated zinc protoporphyrin levels. Blood smears taken from Nan mice show a hypochromic anemia characterized by poikilocytosis, anisocytosis and polychromasia. The Nan phenotype can be transferred by bone marrow transplantation indicating that the defect is intrinsic to bone marrow. The hemolytic anemia in adult Nan mice can be identified by osmotic fragility testing. Examination of the erythrocyte membrane skeleton proteins (EMS) reveals a global deficiency of these proteins with protein 4.1a being completely absent. The Nan locus maps to mouse Chromosome 8 and does not co-localize with any known EMS genes. The identification of the Nan gene will likely uncover a novel protein that contributes to the stability of the EMS and may identify a new mutation for HS.


Assuntos
Anemia Hemolítica/metabolismo , Cromossomos de Mamíferos/genética , Membrana Eritrocítica/metabolismo , Eritrócitos/metabolismo , Proteínas de Membrana/metabolismo , Anemia Hemolítica/genética , Anemia Hemolítica/patologia , Animais , Transplante de Medula Óssea , Mapeamento Cromossômico , Modelos Animais de Doenças , Membrana Eritrocítica/patologia , Eritrócitos/patologia , Eritrócitos/ultraestrutura , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Varredura
9.
J Antimicrob Chemother ; 63(2): 357-60, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19060292

RESUMO

OBJECTIVES: Staphylococcus aureus is the most common pathogen isolated in osteomyelitis. This study evaluated the efficacies of telavancin (an investigational, rapidly bactericidal lipoglycopeptide with a multifunctional mechanism of action against Gram-positive bacteria), vancomycin and linezolid in a rabbit methicillin-resistant S. aureus (MRSA) osteomyelitis model. METHODS: Localized osteomyelitis was induced in New Zealand White rabbits by percutaneous injection of 10(6) cfu of MRSA clinical isolate 168-1 into the intramedullary cavity. Two weeks post-infection, rabbits with radiographically confirmed, localized proximal tibial osteomyelitis were randomized into four groups (n = 15 per group): untreated controls; vancomycin 30 mg/kg subcutaneously every 12 h; linezolid 60 mg/kg orally every 8 h; and telavancin 30 mg/kg subcutaneously every 12 h. After 4 weeks of antibiotic treatment, animals were left untreated for 2 weeks. Rabbits were then euthanized and the tibias harvested. Bone matrix and marrow from each tibia were cultured and bacterial counts determined. RESULTS: For MRSA isolate 168-1, the MIC was 0.25 mg/L for telavancin, 0.5 mg/L for vancomycin and 0.5 mg/L for linezolid. Tibial cultures were positive for MRSA in 9 of 15 (60%) untreated controls, and 3 of 15 (20%) telavancin-treated, 3 of 15 (20%) vancomycin-treated and 4 of 14 (29%) linezolid-treated rabbits. CONCLUSIONS: Telavancin has comparable efficacy to vancomycin and linezolid in a rabbit model of MRSA osteomyelitis.


Assuntos
Aminoglicosídeos/uso terapêutico , Antibacterianos/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Osteomielite/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Acetamidas/uso terapêutico , Animais , Medula Óssea/microbiologia , Contagem de Colônia Microbiana , Linezolida , Lipoglicopeptídeos , Testes de Sensibilidade Microbiana , Osteomielite/microbiologia , Oxazolidinonas/uso terapêutico , Coelhos , Distribuição Aleatória , Infecções Estafilocócicas/microbiologia , Resultado do Tratamento , Vancomicina/uso terapêutico
10.
Am J Emerg Med ; 26(6): 736.e3-4, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18606347

RESUMO

We report a case of ovarian hyperstimulation syndrome (OHSS) in a 37-year-old female who had recently underwent assisted reproductive technology involving oocyte retrieval. Her emergency department (ED) presentation, clinical course, and a discussion of ovarian hyperstimulation syndrome are also presented. Ovarian hyperstimulation syndrome is a critical diagnosis in emergency medicine, and emergency physicians must consider it in the differential for any female nontrauma patient presenting with hypotension, tachycardia, and abdominal pain.


Assuntos
Síndrome de Hiperestimulação Ovariana/diagnóstico , Adulto , Diagnóstico Diferencial , Exsudatos e Transudatos , Feminino , Humanos , Hipotensão/etiologia , Recuperação de Oócitos/efeitos adversos , Síndrome de Hiperestimulação Ovariana/terapia , Taquicardia/etiologia
12.
Blood ; 104(5): 1511-8, 2004 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-15155459

RESUMO

Understanding iron metabolism has been enhanced by identification of genes for iron deficiency mouse mutants. We characterized the genetics and iron metabolism of the severe anemia mutant hea (hereditary erythroblastic anemia), which is lethal at 5 to 7 days. The hea mutation results in reduced red blood cell number, hematocrit, and hemoglobin. The hea mice also have elevated Zn protoporphyrin and serum iron. Blood smears from hea mice are abnormal with elevated numbers of smudge cells. Aspects of the hea anemia can be transferred by hematopoietic stem cell transplantation. Neonatal hea mice show a similar hematologic phenotype to the flaky skin (fsn) mutant. We mapped the hea gene near the fsn locus on mouse chromosome 17 and show that the mutants are allelic. Both tissue iron overloading and elevated serum iron are also found in hea and fsn neonates. There is a shift from iron overloading to iron deficiency as fsn mice age. The fsn anemia is cured by an iron-supplemented diet, suggesting an iron utilization defect. When this diet is removed there is reversion to anemia with concomitant loss of overloaded iron stores. We speculate that the hea/fsn gene is required for iron uptake into erythropoietic cells and for kidney iron reabsorption.


Assuntos
Ferro da Dieta/farmacocinética , Talassemia beta/genética , Talassemia beta/metabolismo , Animais , Animais Recém-Nascidos , Mapeamento Cromossômico , Cromossomos de Mamíferos , Transplante de Tecido Fetal , Transplante de Células-Tronco Hematopoéticas , Ferro da Dieta/sangue , Fígado/citologia , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Fenótipo , Talassemia beta/dietoterapia
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