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1.
Avian Dis ; 65(1): 198-204, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34339140

RESUMO

A series of studies was undertaken in specific-pathogen-free white leghorn chickens for the development of a chicken model of avian pathogenic Escherichia coli (APEC) peritonitis. Once established, this model was then used to measure the effectiveness of a siderophore receptor and porin proteins (SRP®) APEC vaccine. Initially, five pilot studies were performed to compare the E. coli serotype, challenge route, and dose of inoculum that resulted in pathologies characteristic of the peritonitis observed in commercial layer facilities, such as widespread organ infection, atrophy, discoloration, corrugation of yolk sacs, and the presence of caseous exudate. Isolates of serotypes O1, O2, and O78 were tested by intravenous, intravaginal, intratracheal, and intraperitoneal routes and were compared at various levels of challenge inoculum. Daily observations of mortality and morbidity were made, and at necropsy, gross lesion scores were collected and bacterial colonization of internal organs determined. Outcomes varied from a complete lack of mortality or detectable pathology and low, or no, organ colonization in the case of intravaginal and intratracheal routes with each E. coli serotype to moderate to high levels of mortality, pathology, and colonization after challenge via the intravenous and intraperitoneal routes with O2 and O78 serotypes, respectively. The O78 serotype was found to result in pathologies consistent with field observations of peritonitis, and therefore, subsequent studies were performed only with O78. In addition to the relative failure with both the intratracheal and intravaginal routes of challenge, the intravenous route was found to be inconsistent and often resulted in lameness not observed with the intraperitoneal route. A final pilot study confirmed that the dose (∼ 8 log 10 CFU) administered by the intraperitoneal route replicated peritonitis, and therefore, all vaccination/challenge studies were conducted in this manner. Five vaccination/challenge studies are reported here in which variables of chicken age, vaccination interval, and vaccination to challenge interval were examined. In all studies, vaccine effectiveness was dramatic and was shown to completely protect against mortality and substantially against tissue colonization and pathology typical of APEC infections. The vaccine elicited a rapid onset of immunity with both narrow and broad vaccination intervals and in both young and mature chickens. Additionally, the vaccine was demonstrated to sustain robust effectiveness against mortality over 3 months. The SRP APEC vaccine should provide effective protection of young and mature chickens from E. coli under broadly flexible conditions of use in commercial operations.


Artíclo regular­Vacuna para prevenir la peritonitis de gallina de postura. Se llevó a cabo una serie de estudios en aves tipo Leghorn blancas libres de patógenos específicos para el desarrollo de un modelo en pollo para la peritonitis causada por Escherichia coli patógena aviar (APEC). Una vez establecido, este modelo se utilizó para medir la eficacia de una vacuna con proteínas del receptor de sideróforo y de porina (SRP®) de E. coli patógena aviar. Inicialmente, se realizaron cinco estudios piloto para comparar el serotipo de E. coli, la ruta de desafío y la dosis de inóculo que resultaron en patologías características de las peritonitis observadas en instalaciones comerciales de ponedoras, como la infección generalizada de órganos, atrofia, decoloración, ondulación de saco vitelino y la presencia de exudado caseoso. Los aislamientos de los serotipos O1, O2 y O78 se analizaron por vías intravenosa, intravaginal, intratraqueal e intraperitoneal y se compararon a varios niveles de inóculo de desafío. Se realizaron observaciones diarias de mortalidad y morbilidad, en la necropsia, se registraron puntuaciones de lesiones macroscópicas y se determinó la colonización bacteriana de los órganos internos. Los resultados variaron desde una ausencia total de mortalidad o patología detectable y una colonización de órganos baja o nula en el caso de las rutas intravaginal e intratraqueal con cada serotipo de E. coli hasta niveles de mortalidad, patología y colonización de moderados a altos después del desafío por vía intravenosa e intraperitoneal con los serotipos O2 y O78, respectivamente. Se encontró que el serotipo O78 dio como resultado patologías consistentes con las observaciones de campo de la peritonitis y por lo tanto, los estudios posteriores se realizaron solo con el serotipo O78. Además del fracaso relativo con las rutas de desafío intratraqueal e intravaginal, se descubrió que la vía intravenosa era inconsistente y a menudo, provocaba cojera que no se observaba con la vía intraperitoneal. Un estudio piloto final confirmó que la dosis (∼8 log10 UFC) administrada por vía intraperitoneal reproducía la peritonitis y por lo tanto, todos los estudios de vacunación/desafío se realizaron de esta manera. En este estudio se reportan cinco estudios de vacunación/desafío en los que se examinaron las variables de edad del pollo, intervalo de vacunación e intervalo de vacunación al desafío. En todos los estudios, la eficacia de la vacuna fue muy evidente y se demostró que protege completamente contra la mortalidad y sustancialmente contra la colonización de tejidos y la patología típica de las infecciones por E. coli patógena aviar. La vacuna provocó un rápido inicio de la inmunidad con intervalos de vacunación tanto estrechos como amplios y tanto en aves jóvenes como maduras. Además, se demostró que la vacuna mantiene una sólida eficacia contra la mortalidad durante tres meses. La vacuna con proteínas del receptor de sideróforo y de porina de E. coli patógena aviar debería proporcionar una protección eficaz de las aves jóvenes y maduras contra E. coli en condiciones de uso ampliamente flexibles en operaciones comerciales.


Assuntos
Galinhas , Infecções por Escherichia coli/veterinária , Vacinas contra Escherichia coli/administração & dosagem , Escherichia coli/imunologia , Peritonite/veterinária , Doenças das Aves Domésticas/prevenção & controle , Animais , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/prevenção & controle , Feminino , Masculino , Peritonite/microbiologia , Peritonite/prevenção & controle , Projetos Piloto , Doenças das Aves Domésticas/microbiologia
2.
Cancer Res ; 67(7): 3441-9, 2007 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-17409455

RESUMO

Affymetrix U133plus2 GeneChips were used to profile 59 head and neck squamous cell cancers. A hypoxia metagene was obtained by analysis of genes whose in vivo expression clustered with the expression of 10 well-known hypoxia-regulated genes (e.g., CA9, GLUT1, and VEGF). To minimize random aggregation, strongly correlated up-regulated genes appearing in >50% of clusters defined a signature comprising 99 genes, of which 27% were previously known to be hypoxia associated. The median RNA expression of the 99 genes in the signature was an independent prognostic factor for recurrence-free survival in a publicly available head and neck cancer data set, outdoing the original intrinsic classifier. In a published breast cancer series, the hypoxia signature was a significant prognostic factor for overall survival independent of clinicopathologic risk factors and a trained profile. The work highlights the validity and potential of using data from analysis of in vitro stress pathways for deriving a biological metagene/gene signature in vivo.


Assuntos
Carcinoma de Células Escamosas/genética , Hipóxia Celular/genética , Neoplasias de Cabeça e Pescoço/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Família Multigênica , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Regulação para Cima
3.
Clin Cancer Res ; 11(21): 7614-20, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16278379

RESUMO

PURPOSE: The use of erythropoietin in head and neck squamous cell carcinoma (HNSCC) has been associated with poor survival. This study examines the protein and mRNA expression of erythropoietin and erythropoietin receptor in HNSCC and their relation to hypoxia, hemoglobin (Hb), and clinical outcome. EXPERIMENTAL DESIGN: The immunohistochemical expression of erythropoietin and erythropoietin receptor was assessed in 151 cases of HNSCC. Expression was compared with the hypoxia-dependent proteins hypoxia-inducible factor-1alpha (HIF-1alpha) and carbonic anhydrase-9 (CA-9) and correlated with clinical outcome. The mRNA expression of erythropoietin and erythropoietin receptor was measured in paired samples of HNSCC. RESULTS: Erythropoietin and erythropoietin receptor were expressed in 95% and 99% of tumors, respectively. Using a weighed expression score, there was a positive correlation between erythropoietin and erythropoietin receptor expression (r = 0.18, P = 0.03). HIF-1alpha (r = 0.38, P < 0.01) and CA-9 (r = 0.26, P = 0.002) correlated with erythropoietin expression, but there was no correlation with erythropoietin receptor. No correlation was found between Hb and erythropoietin (r = 0.07, P = 0.36) or erythropoietin receptor (r = -0.02, P = 0.8), and no survival difference between high and low erythropoietin or erythropoietin receptor expression (P = 0.59 and P = 0.98, respectively). The mRNA expression of erythropoietin (P = 0.03) but not erythropoietin receptor (P = 0.62) was significantly increased in 11 paired samples of HNSCC. CONCLUSION: In vivo, the HIF pathway regulates erythropoietin at the mRNA level but not erythropoietin receptor expression in HNSCC. Anemia does not seem to influence the hypoxic microenvironment of tumors sufficiently to alter the expression of erythropoietin. The effects of exogenous erythropoietin may be acting via receptors expressed on tumor cells in vivo, or on vascular cells, which also express the pathway.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Eritropoetina/biossíntese , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/metabolismo , Hipóxia , Receptores da Eritropoetina/biossíntese , Anemia , Antígenos de Neoplasias/biossíntese , Anidrase Carbônica IX , Anidrases Carbônicas/biossíntese , Citoplasma/metabolismo , DNA Complementar/metabolismo , Intervalo Livre de Doença , Feminino , Seguimentos , Hemoglobinas/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Análise Serial de Proteínas , RNA/química , RNA/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica , Resultado do Tratamento
4.
Cancer Res ; 62(9): 2493-7, 2002 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11980639

RESUMO

Hypoxia within head and neck squamous cell carcinoma (HNSCC) predicts a poor response to radiotherapy and poor prognosis. Hypoxia-inducible factor (HIF)-1 and HIF-2 are nuclear transcription factors that regulate the cellular response to hypoxia and are important for solid tumor growth and survival. Overexpression of HIF-1alpha and HIF-2alpha was demonstrated in three HNSCC cell lines under hypoxia and tumor tissue versus normal tissue (n = 20, HIF-1alpha, P = 0.023; HIF-2alpha, P = 0.013). On immunostaining, HIF-1alpha and HIF-2alpha expression were localized to tumor nuclei; HIF-2alpha expression was also seen in tumor-associated macrophages. Expression of HIF-1alpha in surgically treated patients with HNSCC (n = 79) was associated with improved disease-free survival (P = 0.016) and overall survival (P = 0.027).


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Transativadores/biossíntese , Fatores de Transcrição/biossíntese , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Intervalo Livre de Doença , Células HeLa , Neoplasias de Cabeça e Pescoço/irrigação sanguínea , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Imuno-Histoquímica , L-Lactato Desidrogenase/metabolismo , Pessoa de Meia-Idade , Necrose , Taxa de Sobrevida , Resultado do Tratamento
5.
J Laryngol Otol ; 116(9): 744-5, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12437817

RESUMO

Epithelioid sarcoma (ES) is a rare tumour that seldom presents to the otolaryngologist. It typically occurs in the extremities of young adolescents; however, it has the capability of metastasizing, often to the lungs or skin. The diagnosis is by histopathological examination and immunohistochemistry. We present a case of metastatic ES occuring in the tongue, a tumour not reported previously in the English literature.


Assuntos
Sarcoma/secundário , Neoplasias Cutâneas/patologia , Neoplasias da Língua/secundário , Transtornos de Deglutição/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sarcoma/cirurgia , Neoplasias da Língua/cirurgia
7.
Ann R Coll Surg Engl ; 89(7): 703-8, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17959009

RESUMO

INTRODUCTION: Treatment of advanced neck disease (N2c/N3) in head and neck squamous cell carcinoma is contentious. The aim of this study was to review the survival outcome following surgical excision of neck disease and the complications of this surgery. PATIENTS AND METHODS: A retrospective review of the case notes of 39 patients treated at the Oxford Radcliffe Infirmary Head and Neck Unit with squamous cell carcinoma and advanced neck metastases confirmed as either pN2c or pN3 on histological examination was performed. Patients were treated with surgery and, in some cases, with adjunctive postoperative radiotherapy at the centre between August 1996 and November 2004. The study sought to establish the demographics, UICC staging/pathology, method of treatment, complications, recurrence and survival. Kaplan-Meier curves were used for statistical analysis of survival. Comparisons were then made between the cohort and historical control groups. RESULTS: All patients were UICC stage IV disease. The 2- and 5-year overall survival in patients with resectable disease was 63% and 52%, respectively. DISCUSSION: Patients with advanced neck disease have traditionally been thought to have terrible prognosis and, therefore, treatment is controversial. In treating advanced head and neck cancer, there has been a recent trend away from surgery towards chemotherapy and/or radiotherapy. CONCLUSIONS: Comparing this study group to historical controls that include chemotherapy and/or radiotherapy, the outcomes appear favourable. The use of a combination of radiotherapy and surgery is advocated; it is suggested that advanced neck disease can have an acceptable prognosis and morbidity and that local disease control may be achieved.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Neoplasias de Cabeça e Pescoço/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical , Cuidados Pós-Operatórios/métodos , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
8.
Cancer ; 107(4): 757-66, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16826581

RESUMO

BACKGROUND: Hypoxia promotes tumorigenesis through the hypoxia-inducible factor (HIF) pathway. There are 2 main homologues of the regulatory proteins, HIF-1alpha and HIF-2alpha, which have different effects in genetic knock-out experiments. Anemia may contribute to hypoxia by reducing oxygen delivery, but it is not known whether this influences HIF-alpha expression in tumors. METHODS: The expression of HIF-1alpha, HIF-2alpha, carbonic anhydrase-9 (CA-9), and peripheral hemoglobin (Hb) levels in 151 patients who underwent surgery for head and neck squamous cell carcinoma (HNSCC) were analyzed and related to outcome. RESULTS: High HIF-1alpha was expressed in 45 of 140 tumors (30%), HIF-2alpha was expressed in 21 of 139 tumors (14%), and CA-9 was expressed in 56 of 149 tumors (62%). There was a positive correlation between HIF-1alpha expression and HIF-2alpha expression (P =.0001). HIF-1alpha alone was associated with a worse disease-specific survival (DSS) (P =.05) and disease-free survival (DFS) (P = .03) in multivariate analyses. Nine percent of tumors expressed both high HIF-1alpha and high HIF-2alpha. High HIF-1alpha/high HIF-2alpha expression was an independent prognostic factors in DSS (P = .04) and DFS (P =.005) in multivariate analyses. There was no correlation noted between Hb and HIF-1alpha, HIF-2alpha, or CA-9. CONCLUSIONS: HIF-1alpha alone was correlated with DSS and DFS. The additive effect of HIF-2alpha on poor prognosis suggested that different pathways may be regulated by HIF-2alph. Anemia that was not related to HIF-alpha expression suggests that tumor intrinsic factors regulate HIF-alpha therefore, anemia may be a surrogate marker for other factors that affect outcome.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Anidrase Carbônica IX , Anidrases Carbônicas/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Estudos de Coortes , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/cirurgia , Hemoglobinas/metabolismo , Humanos , Hipóxia , Masculino , Prognóstico , Taxa de Sobrevida , Fatores de Tempo , Regulação para Cima
9.
J Otolaryngol ; 32(2): 107-9, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12866595

RESUMO

OBJECTIVE: To evaluate the role of chest radiography versus chest computed tomography (CT) in screening for pulmonary malignancy in advanced head and neck squamous cell carcinoma (HNSCC). DESIGN: Retrospective review of imaging. SETTING: Head and neck cancer unit. METHOD: Over a period of 1 year, 26 patients with advanced HNSCC (T3/T4) were screened for pulmonary malignancy with both chest radiography and chest CT prior to definitive therapy. OUTCOME MEASURES: Radiologic evidence of malignancy. RESULTS: Twenty patients had a normal chest radiograph and a normal CT scan. Four patients had a normal chest radiograph but an abnormal CT scan. Three of these patients had a pulmonary malignancy and one had a suspicious lesion that resolved following surgery to the index tumour. Two patients had both an abnormal chest radiograph and CT scan. One of these had a pulmonary malignancy and one had a CT-guided biopsy of the chest lesion 4 weeks postoperatively, which was normal. Chest CT scanning therefore identified three chest malignancies that would have been missed by chest radiography alone. CONCLUSIONS: Chest CT is an effective tool in screening for malignant pulmonary disease in patients with advanced head and neck cancer and should be used instead of chest radiography to avoid false-negative results.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/secundário , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/secundário , Segunda Neoplasia Primária/diagnóstico por imagem , Segunda Neoplasia Primária/patologia , Radiografia Torácica , Tomografia Computadorizada por Raios X , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reprodutibilidade dos Testes , Estudos Retrospectivos
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