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1.
Surgery ; 165(1): 17-24, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30360906

RESUMO

BACKGROUND: The ThyroSeq v2 next-generation sequencing assay estimates the probability of malignancy in indeterminate thyroid nodules. Its diagnostic accuracy in different practice settings and patient populations is not well understood. METHODS: We analyzed 273 Bethesda III/IV indeterminate thyroid nodules evaluated with ThyroSeq at 4 institutions: 2 comprehensive cancer centers (n = 98 and 102), a multicenter health care system (n = 60), and an academic medical center (n = 13). The positive and negative predictive values of ThyroSeq and distribution of final pathologic diagnoses were analyzed and compared with values predicted by Bayes theorem. RESULTS: Across 4 institutions, the positive predictive value was 35% (22%-43%) and negative predictive value was 93% (88%-100%). Predictive values correlated closely with Bayes theorem estimates (r2 = 0.84), although positive predictive values were lower than expected. RAS mutations were the most common molecular alteration. Among 84 RAS-mutated nodules, malignancy risk was variable (25%, range 10%-37%) and distribution of benign diagnoses differed across institutions (adenoma/hyperplasia 12%-85%, noninvasive follicular thyroid neoplasm with papillary-like nuclear features 5%-46%). CONCLUSION: In a multi-institutional analysis, ThyroSeq positive predictive values were variable and lower than expected. This is attributable to differences in the prevalence of malignancy and variability in pathologist interpretations of noninvasive tumors. It is important that clinicians understand ThyroSeq performance in their practice setting when evaluating these results.


Assuntos
Testes Genéticos/instrumentação , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Neoplasias da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/genética , Nódulo da Glândula Tireoide/patologia , Adenocarcinoma Folicular/genética , Adenocarcinoma Folicular/patologia , Adulto , Teorema de Bayes , Biópsia por Agulha Fina , Feminino , Frequência do Gene , Fusão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Análise de Sequência de DNA , Análise de Sequência de RNA , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia
2.
Oral Oncol ; 78: 171-176, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29496047

RESUMO

OBJECTIVES: Describe the influence of pretreatment tracheotomy and treatment modality (surgical versus non-surgical) on oncologic and functional outcomes. MATERIALS AND METHODS: Retrospective study of previously untreated advanced-stage laryngeal squamous cell carcinoma patients at two academic tertiary care institutions from 1995 to 2014. RESULTS: Primary outcomes evaluated were disease-free survival, disease-specific survival, and overall survival of pretreatment tracheotomy versus no pretreatment tracheotomy cohorts. Functional status, measured by tracheotomy decannulation and gastrostomy tube placement/removal, was assessed. Of the 226 patients, 31.4% underwent pretreatment tracheotomy. Five-year disease-specific survival was 72.9%, and overall survival was 48.8% for entire cohort. There was a statistically significant decrease in overall survival (p = .03) and disease-free survival (p = .02) for the pretreatment tracheotomy group compared to no pretreatment tracheotomy, which was largely explained by primary tumor stage. Pretreatment tracheotomy was associated with gastrostomy tube placement and was an independent predictor of worse odds of gastrostomy tube removal. Disease stage, distant metastasis, and age independently conferred worse odds of gastrostomy tube removal. CONCLUSION: Patients undergoing pretreatment tracheotomy for primary T4 laryngeal cancer had decreased overall survival compared to patients without pretreatment tracheotomy. There was no difference in local recurrence rates based on tracheotomy status. Organ preservation with chemotherapy and radiation did not result in better functional outcomes than surgery in the pretreatment tracheotomy group as nearly half of patients treated with organ preservation remained tracheotomy dependent. Based on this data, pretreatment tracheotomy may impact oncologic and functional outcomes in advanced disease, and it should be a consideration in an informed decision-making process.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Neoplasias Laríngeas/cirurgia , Traqueotomia , Adulto , Idoso , Carcinoma de Células Escamosas/fisiopatologia , Feminino , Humanos , Neoplasias Laríngeas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento
3.
Oper Tech Otolayngol Head Neck Surg ; 29(3): 157-161, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30853770

RESUMO

Salivary gland carcinomas are diverse, and their biological behavior and surgical management are also variable and somewhat controversial. Cervical lymph node status is an important prognostic variable for salivary gland malignancies. Neck dissection should be undertaken if there is clinical or radiographic evidence of associated nodal metastasis in the neck. However, indications for elective neck dissections in a clinically N0 neck remains a controversial topic. This article describes indications for elective neck dissection in salivary gland malignancies, provides a detailed review of the neck dissection technique, and discusses postoperative management of these patients.

4.
Oral Oncol ; 68: 5-8, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28438292

RESUMO

OBJECTIVE: Mucoepidermoid carcinoma (MEC) is the most common malignant tumor of the salivary glands. Tumor stage and grade have historically been important predictors of survival. An oncogenic CRTC1- or CRTC3-MAML2 gene fusion has been identified in a number of MECs. Historically, these gene fusions have been associated with lower grade tumors and better survival. However, reported gene fusion rates and prognosis varies widely across studies, and have not controlled for tumor grade. We sought to identify gene fusion rates and outcomes in our cohort of MEC patients. MATERIALS AND METHODS: An IRB-approved retrospective cohort of patients with MEC was identified at the University of Michigan. Clinical, histologic, and outcome data was collected from medical records. RNA was isolated from formalin fixed paraffin-embedded tumor sections, and qRT-PCR was performed to identify CRTC1/3-MAML2 gene fusions. Sanger sequencing of qRT-PCR products was used to confirm gene fusions. RESULTS: Overall, 90 patient MEC tumors were collected (58 low-grade, 25 intermediate-grade, and 7 high-grade). Gene fusions were identified in 59% (53/90) of tumors. On univariate and bivariate analysis, fusion status did not significantly associate with grade or survival. CONCLUSION: We have identified a high rate of CRTC1/3-MAML2 gene fusions in a large cohort of MEC. We do not identify any correlation between fusion status with tumor grade or survival. These findings suggest further characterization of MECs is needed before considering the CRTC1/3-MAML2 gene fusion as a prognostic biomarker. Additional genetic drivers may account for survival and grade in MECs.


Assuntos
Carcinoma Mucoepidermoide/patologia , Proteínas de Ligação a DNA/genética , Fusão Gênica , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Carcinoma Mucoepidermoide/genética , Estudos de Coortes , Feminino , Humanos , Masculino , Mutação , Estudos Retrospectivos , Análise de Sobrevida , Transativadores
5.
Case Rep Otolaryngol ; 2017: 4935123, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28286685

RESUMO

A 41-year-old female with a history of uterine cancer and Celiac and Raynaud's Disease presented to our institution with frequent migraines and nasal congestion. She underwent functional endoscopic sinus surgery (FESS) and experienced acute unilateral vision loss postoperatively. Rapid recognition of the etiology and effective treatment are paramount given the permanent and irreversible vision loss that can result. Arterial vasospasm following FESS is rare. Patients with autoimmune diseases have perhaps an increased risk for vasospasm secondary to an increased vasoreactive profile. We present the first documented case of nitroglycerin sublingual therapy to successfully treat ophthalmic artery vasospasm following FESS. Nitroglycerin sublingual therapy is a promising treatment for ophthalmic vasospasm secondary to its ability to cross the blood-ocular barrier, its rapid onset of action, and its ability to promote relaxation of vascular smooth muscle.

6.
Oral Oncol ; 50(5): 513-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24565983

RESUMO

BACKGROUND: To determine whether the addition of molecular and imaging biomarkers to established clinical risk factors could help predict locoregional failure (LRF) after chemoradiation in human papillomavirus (HPV)-related (+) oropharyngeal cancer (OPC) and improve patient selection for locoregional treatment de-intensification. METHODS: HPV status was determined for 198 consecutive patients with stage III/IV OPC treated with definitive chemoradiation from 5/2003 to 10/2010. The impact of pre-therapy epidermal growth factor receptor (EGFR) overexpression; imaging biomarkers including primary tumor and nodal maximum standardized uptake values on FDG-PET, gross tumor volumes, and matted nodes; and clinical factors on LRF (including residual disease at adjuvant neck dissection) was assessed. RESULTS: Primary tumors were HPV+ in 184 patients and HPV-negative in 14. EGFR overexpression was related to HPV-negative status and was univariately associated with LRF in the overall population, but was neither retained in the multivariate model after adjustment for HPV status, nor associated with LRF in HPV+ patients. Similarly, imaging biomarkers were univariately associated with LRF, but correlated with T-stage and/or N-stage and did not remain predictive in HPV+ patients after adjustment for T4- and N3-stages, which were the only significant predictors of LRF on multivariate analysis. Among HPV+ patients with non-T4- or N3-stages, only minimal smoking was associated with decreased LRF. CONCLUSIONS: The prognostic impact of EGFR overexpression and imaging biomarkers on LRF was predominantly related to their association with HPV-negative status and T- or N-stage, respectively. Among HPV+ OPC patients treated with uniform chemoradiation, only T4-stage, N3-stage, and smoking contributed to risk-stratification for LRF.


Assuntos
Neoplasias Orofaríngeas/tratamento farmacológico , Neoplasias Orofaríngeas/radioterapia , Papillomaviridae/isolamento & purificação , Adulto , Idoso , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/virologia , Medição de Risco , Resultado do Tratamento
7.
Head Neck ; 36(5): 617-23, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23596055

RESUMO

BACKGROUND: Optimal treatment for locally advanced squamous cell carcinoma of the oropharynx (SCCOP) is not well defined. Here we retrospectively compare survival and toxicities from 2 different organ preservation protocols. METHODS: The matched dataset consisted of 35 patients from each trial matched for age, stage, smoking, and tumor human papillomavirus (HPV) status. Patients in the University of Michigan Cancer Center (UMCC) trial 9921 were treated with induction chemotherapy (IC) followed by high-dose cisplatin and radiation in responders or surgery in nonresponders. Patients in the UMCC trial 0221 were treated with weekly carboplatin and paclitaxel and radiation. RESULTS: Survival was comparable for both studies and did not differ significantly across each trial after stratifying by HPV status. Grade 3 and 4 toxicities were more frequent in UMCC 9921. At 6 months posttreatment, gastrostomy tube (G-tube) dependence was not statistically different. CONCLUSION: These data suggest that survival outcomes in patients with locally advanced SCCOP are not compromised with weekly chemotherapy and radiation therapy, and such treatment is generally more tolerable.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Cisplatino/administração & dosagem , Papillomavirus Humano 6/isolamento & purificação , Neoplasias Orofaríngeas/tratamento farmacológico , Neoplasias Orofaríngeas/radioterapia , Idoso , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/uso terapêutico , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Terapia Combinada , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Preservação de Órgãos , Neoplasias Orofaríngeas/mortalidade , Neoplasias Orofaríngeas/patologia , Paclitaxel/uso terapêutico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Pulsoterapia/métodos , Radioterapia de Alta Energia/métodos , Medição de Risco , Testes Sorológicos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
8.
Head Neck ; 36(9): 1233-40, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23913653

RESUMO

BACKGROUND: The current American Joint Committee on Cancer (AJCC) staging system may not accurately reflect survival in patients with human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (SCC). The purpose of this study was to develop a system that more precisely predicts survival. METHODS: CT scans from 156 patients who underwent chemoradiation for advanced-stage oropharyngeal SCC with >2 years follow-up were reviewed. We modeled patterns of nodal metastasis associated with different survival rates. We defined HPV+ N1 as a single node <6 cm, ipsilaterally, contralaterally, or bilaterally. HPV+ N2 was defined as a single node ≥6 cm or ≥2 nodes ipsilaterally/contralaterally or ≥3 nodes bilaterally. HPV+ N3 was defined as matted nodes. RESULTS: There was no significant difference in disease-specific survival (DSS; p = .14) or overall survival (OS; p = .16) by AJCC classification. In patients grouped by HPV+ N1, HPV+ N2, and HPV+ N3 nodal classification, significant differences in DSS (100%, 92%, and 55%, respectively; p = .0001) and OS (100%, 96%, and 55%, respectively; p = .0001) were found. CONCLUSION: A staging system with reclassification of size, bilaterality, and matted nodes more accurately reflects survival differences in this cohort of patients. Review of the AJCC staging system with these criteria should be considered for HPV-positive oropharyngeal SCC.


Assuntos
Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/secundário , Linfonodos/patologia , Neoplasias Orofaríngeas/mortalidade , Neoplasias Orofaríngeas/patologia , Infecções por Papillomavirus/mortalidade , Infecções por Papillomavirus/patologia , Carcinoma de Células Escamosas/virologia , Estudos de Coortes , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Neoplasias Orofaríngeas/virologia , Prognóstico , Taxa de Sobrevida
9.
JAMA Otolaryngol Head Neck Surg ; 139(12): 1320-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24177760

RESUMO

IMPORTANCE: Human papillomaviruses are now recognized as an etiologic factor in a growing subset of head and neck cancers and have critical prognostic importance that affects therapeutic decision making. There is no universally accepted gold standard for high-risk HPV (hrHPV) assessment in formalin-fixed, paraffin-embedded (FFPE) tissue specimens, nor is there a clear understanding of the frequency or role of hrHPV in sites other than oropharynx. OBJECTIVE: To determine the optimal assessment of hrHPV in FFPE head and neck tumor tissue specimens. DESIGN, SETTING, PARTICIPANTS: In the setting of a large Midwestern referral center, assessment of hrHPV by p16 immunohistochemical staining, in situ hybridization, and polymerase chain reaction (PCR)-MassArray (PCR-MA), with L1 PGMY-PCR and sequencing to resolve method discordance, was conducted for 338 FFPE oropharyngeal, nasopharyngeal, and oral cavity tumor tissue specimens. Relative sensitivity and specificity were compared to develop a standard optimal test protocol. Tissue specimens were collected from 338 patients with head and neck cancer treated during the period 2001 through 2011 in the departments of Otolaryngology, Radiation Oncology, and Medical Oncology. INTERVENTION: Patients received standard therapy. MAIN OUTCOMES AND MEASURES: Optimal hrHPV identification, detection, and activity in head and neck cancers. RESULTS: Using combined PCR-MA with L1 PGMY-PCR and sequencing for conclusive results, we found PCR-MA to have 99.5% sensitivity and 100% specificity, p16 to have 94.2% sensitivity and 85.5% specificity, and in situ hybridization to have 82.9% sensitivity and 81.0% specificity. Among HPV-positive tumors, HPV16 was most frequently detected, but 10 non-HPV16 types accounted for 6% to 50% of tumors, depending on the site. Overall, 86% of oropharynx, 50% of nasopharynx, and 26% of oral cavity tumors were positive for hrHPV. CONCLUSIONS AND RELEVANCE: PCR-MA has a low DNA (5 ng) requirement effective for testing small tissue samples; high throughput; and rapid identification of HPV types, with high sensitivity and specificity. PCR-MA together with p16INK4a provided accurate assessment of HPV presence, type, and activity and was determined to be the best approach for HPV testing in FFPE head and neck tumor tissue specimens.


Assuntos
Neoplasias Bucais/virologia , Neoplasias Nasofaríngeas/virologia , Neoplasias Orofaríngeas/virologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/diagnóstico , Infecções Tumorais por Vírus/diagnóstico , Adulto , Idoso , Biópsia por Agulha , Bases de Dados Factuais , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Hibridização In Situ/métodos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Neoplasias Nasofaríngeas/patologia , Neoplasias Orofaríngeas/patologia , Papillomaviridae/patogenicidade , Inclusão em Parafina , Reação em Cadeia da Polimerase/métodos , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medição de Risco , Sensibilidade e Especificidade
10.
Otolaryngol Head Neck Surg ; 149(3): 402-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23695589

RESUMO

OBJECTIVE: To describe the epidemiology and determine the clinicopathologic predictors of recurrence and survival in patients with head and neck mucoepidermoid carcinoma (MEC). STUDY DESIGN: Case series with chart review. SETTING: Tertiary care hospital. SUBJECTS AND METHODS: The medical records of 101 patients who underwent surgical treatment at the University of Michigan for head and neck MEC between 1985 and 2010 were reviewed. Main outcome measures were disease-free survival (DFS), disease-specific survival (DSS), and overall survival. Clinicopathologic parameters evaluated were age, sex, subsite, histological grade, adjuvant therapy, T stage, nodal status with/without extracapsular spread, and margin status. RESULTS: Of the 101 patients, 38 parotid, 33 palate, 17 oral, 8 submandibular/sublingual, 4 orbital, and 1 parapharyngeal carcinomas were identified. All patients underwent surgical resection, 23 had postoperative radiation, and 2 had postoperative chemoradiation. The 5-year OS and DSS was 79% and 95% with a median follow-up of 72 and 45 months, respectively. Five-year DFS was 76%. On univariate analysis, histological grade was a statistically significant predictor of disease-free survival (P = .001) and overall survival (P = .04). Positive nodal status was a significant predictor of DSS (P = .004). There was no statistically significant difference in DFS, DSS, or OS based on sex, age, anatomic subsite, T stage, adjuvant therapy, and margin status. CONCLUSION: Advanced histological grade and positive nodal status are the strongest independent predictors of prognosis in head and neck MEC patients. Further studies into the molecular biology of MEC that may account for such clinicopathological features are currently underway.


Assuntos
Carcinoma Mucoepidermoide/patologia , Neoplasias de Cabeça e Pescoço/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Mucoepidermoide/epidemiologia , Carcinoma Mucoepidermoide/cirurgia , Criança , Feminino , Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Taxa de Sobrevida
11.
Laryngoscope ; 121(8): 1800-4, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21792972

RESUMO

OBJECTIVE: To explore the ethics of parental refusal of auditory-oral hearing rehabilitation. STUDY DESIGN: Case study with medical ethical discussion and review. METHODS: Two young brothers present with severe-to-profound congenital sensorineural hearing loss. The parents, both of whom have normal hearing and work as sign language interpreters, have decided to raise their children with American Sign Language as their only form of communication. They have chosen not to pursue cochlear implantation nor support the use of hearing aids. DISCUSSION: This case raises significant questions concerning whether hearing rehabilitation should be mandated, and if there are circumstances in which parental preferences should be questioned or overridden with regard to this issue. In addition, legal concerns may be raised regarding the possible need to file a report with Child Protective Services. Although similar cases involving the Deaf community have historically favored parental rights to forego hearing rehabilitation with either cochlear implantation or hearing aids, we explore whether conclusions should be different because the parents in this case are not hearing impaired. CONCLUSIONS: The ethics of parental rights to refuse hearing rehabilitation are complex and strikingly context-dependent. A comprehensive appreciation of the medical, practical, and legal issues is crucial prior to intervening in such challenging situations.


Assuntos
Implante Coclear/ética , Perda Auditiva Neurossensorial/cirurgia , Pais/psicologia , Recusa do Paciente ao Tratamento/ética , Pré-Escolar , Perda Auditiva Neurossensorial/congênito , Humanos , Lactente , Masculino , Consentimento dos Pais/ética , Pessoas com Deficiência Auditiva/psicologia
12.
J Virol ; 82(18): 9086-93, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18614642

RESUMO

Assembly of adenovirus particles is thought to be similar to that of bacteriophages, in which the double-stranded DNA genome is inserted into a preformed empty capsid. Previous studies from our and other laboratories have implicated the viral IVa2 protein as a key component of the encapsidation process. IVa2 binds to the packaging sequence on the viral chromosome in a sequence-specific manner, alone and in conjunction with the viral L4 22K protein. In addition, it interacts with the viral L1 52/55-kDa protein, which is required for DNA packaging. Finally, a mutant virus that does not produce IVa2 is unable to produce any capsids. Therefore, it has been proposed that IVa2 nucleates capsid assembly. A prediction of such a model is that the IVa2 protein would be found at a unique vertex of the mature virion. In this study, the location of IVa2 in the virion has been analyzed using immunogold staining and electron microscopy, and the copy number of IVa2 in virions was determined using three independent methods, quantitative mass spectrometry, metabolic labeling, and Western blotting. The results indicate that it resides at a unique vertex and that there are approximately six to eight IVa2 molecules in each particle. These findings support the hypothesis that the IVa2 protein plays multiple roles in the viral assembly process.


Assuntos
Adenovírus Humanos/metabolismo , Proteínas Virais/metabolismo , Vírion/metabolismo , Vírion/ultraestrutura , Montagem de Vírus , Adenovírus Humanos/patogenicidade , Western Blotting , Capsídeo/metabolismo , Linhagem Celular , Dosagem de Genes , Células HeLa , Humanos , Imuno-Histoquímica , Espectrometria de Massas , Microscopia Eletrônica , Proteínas Virais/genética
13.
J Virol ; 81(22): 12450-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17804492

RESUMO

Assembly of infectious adenovirus particles requires seven functionally redundant elements at the left end of the genome, termed A repeats, that direct packaging of the DNA. Previous studies revealed that the viral IVa2 protein alone interacts with specific sequences in the A repeats but that additional IVa2-containing complexes observed during infection require the viral L4 22-kDa protein. In this report, we purified a recombinant form of the 22-kDa protein to characterize its DNA binding properties. In electrophoretic mobility shift assay analyses, the 22-kDa protein alone did not interact with the A repeats but it did form complexes on them in the presence of the IVa2 protein. These complexes were identical to those seen in extracts from infected cells and had the same DNA sequence dependence. Furthermore, we provide data that the 22-kDa protein enhances binding of the IVa2 protein to the A repeats and that multiple binding sites in the packaging sequence augment this activity. These data support a cooperative role of the IVa2 and 22-kDa proteins in packaging and assembly.


Assuntos
Adenoviridae/fisiologia , DNA Viral/metabolismo , Proteínas Virais/metabolismo , Montagem de Vírus , Animais , Sequência de Bases , DNA Viral/química , Ensaio de Desvio de Mobilidade Eletroforética , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Virais/química , Proteínas Virais/isolamento & purificação
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