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1.
Clin Otolaryngol ; 43(1): 192-198, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28714274

RESUMO

OBJECTIVES: Lymph node ratio (LNR) is an established predictor in different entities of carcinoma, including head and neck malignancies. In oropharyngeal squamous cell carcinoma (OPSCC), lymph node involvement differs between human papilloma virus (HPV)-positive and HPV-negative tumours. Herein, we evaluate the impact of HPV association on the concept of LNR. METHODS: 88 surgically treated patients were included in this retrospective chart review. HPV-positive and HPV-negative OPSCC were evaluated for prediction of outcome by LNR separately. The endpoints were 5-year overall survival (OS) and recurrence-free survival (RFS). RESULTS: The OS of all patients was 60.1%. In univariate analysis, LNR was a significant predictor of overall survival rate (P=.008) in OPSCC independently of the HPV status, as well as extracapsular spread (ECS). T-classification was only a significant predictor in the univariate analysis in HPV-positive OPSCC carcinoma. However, in the multivariate analysis LNR remained predictor of prognosis in all OPSCC and in HPV-negative OPSCC. In patients with HPV-positive OPSCC, only T-classification reached significance to predict OS. CONCLUSION: Prognosis of primarily operated HPV-positive patients might be more dependent on the extent of primary tumour site, whereas prognosis of HPV-negative patients is based more on cervical metastatic spread, represented by LNR.


Assuntos
Carcinoma de Células Escamosas/secundário , Linfonodos/diagnóstico por imagem , Estadiamento de Neoplasias , Neoplasias Orofaríngeas/diagnóstico , Papillomaviridae , Infecções por Papillomavirus/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Pescoço , Procedimentos Cirúrgicos Bucais , Neoplasias Orofaríngeas/epidemiologia , Neoplasias Orofaríngeas/cirurgia , Infecções por Papillomavirus/virologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Tomografia Computadorizada por Raios X
2.
Clin Otolaryngol ; 42(1): 98-103, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27185037

RESUMO

OBJECTIVE: Lymph node ratio (LNR) has been shown to be an independent predictor of recurrence risk and survival in different entities of carcinoma. METHODS: In this retrospective chart review, 128 patients with parotid gland cancer (PGC) subsequently treated by primary surgery were included. About 64% (n = 82) of these patients were additionally treated with adjuvant radiotherapy. Five-year overall survival rates were determined by subgroups based on LNR value. RESULTS: Lymph node ratio was found to be significantly associated with overall survival rate (P < 0.001). Using univariate analyses, pathological tumour-node-metastasis (TNM)-stage, UICC-stage grouping and extracapsular spread were found to be significant predictors of overall survival (P < 0.001). However, with a multivariate analyses, LNR remained the only independent predictor of overall survival (P = 0.043). CONCLUSIONS: After surgery for PGC, evaluation of the neck using LNR was found to reliably stratify the overall survival rate.


Assuntos
Carcinoma/patologia , Carcinoma/cirurgia , Excisão de Linfonodo , Linfonodos/patologia , Neoplasias Parotídeas/patologia , Neoplasias Parotídeas/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Parotídeas/mortalidade , Valor Preditivo dos Testes , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
3.
Int J Cancer ; 133(10): 2454-63, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23649428

RESUMO

To identify possible predictive markers, our study aimed to characterize microRNA (miRNA) profiles of responder and nonresponder in the multimodality therapy of locally advanced esophageal cancer. Initially, a microarray-based approach was performed including eight patients with esophageal cancer. Patients received neoadjuvant chemoradiation followed by surgical resection. Major histopathological response was defined if resected specimens contained less than 10% vital tumor cells (major/minor response: 4/4 patients). Intratumoral RNA was isolated from both, pretherapeutic tissue biopsies in addition to corresponding surgical specimens. The profile of 768 miRNAs was analyzed in 16 specimens (preneoadjuvant and postneoadjuvant therapy). Selected miRNAs were than analyzed on pretherapeutic and post-therapeutic biopsies of 80 patients with esophageal cancer, who underwent multimodality therapy (major/minor response: 30/50 patients). Comprehensive miRNA profiling identified miRNAs in pretherapeutic biopsies that were significantly different between major/minor responders. Based on the microarray results, miR-192, miR-194 and miR-622 were selected and the dysregulated miRNAs were studied on an extended series of esophageal cancer patients. The expression of miR-192, miR-194 and miR-622 was significantly reduced after neoadjuvant therapy confirming the array profiling data. Importantly, the pretherapeutic intratumoral expression of miR-192 and miR-194 was significantly associated with the histopathologic response of esophageal squamous cell carcinoma to multimodal therapeutic treatment. Therefore, in patients with locally advanced esophageal cancer undergoing neoadjuvant chemoradiation followed by esophagectomy, miR-192 and miR-194 in pretherapeutic biopsies are considered as indicators of major histopathologic regression.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/terapia , MicroRNAs/genética , Biópsia/métodos , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Terapia Combinada/métodos , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Resultado do Tratamento
4.
Pathologe ; 34(1): 16-24, 2013 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-23389825

RESUMO

Lung cancer is one of the most frequent malignancies in the western world. Its frequent association with a wide spectrum of mutations in genes encoding various signal transducers that are often linked to therapy response, emphasizes the obvious need for improved, fast and highly efficient approaches in molecular pathology. Comprehensive analyses of the mutation status of progression and therapy relevant genes can be performed by the novel sequencing forms named next generation sequencing (NGS) providing extremely high capacities for ultra-deep sequence analyses. The 454 pyrosequencing method, the sequencing by synthesis and the semiconductor sequencing platform are now available for parallel sequencing approaches of multitudinous target genes linked to multiple tumor DNA applications. The "one molecule, one clone, one read" principle by the NGS approaches supplies not only information on allele frequencies and mutation rates but also has the advantage of a very sensitive detection of low frequency variants.


Assuntos
Marcadores Genéticos/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Sequenciamento de Nucleotídeos em Larga Escala/tendências , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Patologia Molecular/educação , Patologia Molecular/tendências , Adenocarcinoma/genética , Adenocarcinoma/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Análise Mutacional de DNA/métodos , Análise Mutacional de DNA/tendências , Progressão da Doença , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica/genética , Frequência do Gene/genética , Humanos , Pulmão/patologia , Neoplasias Pulmonares/terapia , Medicina de Precisão/métodos , Medicina de Precisão/tendências , Prognóstico , Transdução de Sinais/genética
5.
Pathologe ; 32(5): 418-27, 2011 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-21792604

RESUMO

Human cytomegalovirus, a double-stranded DNA virus, is a member of the Herpesviridae family with high rates of transmission. Primary infection is often asymptomatic and leads to life-long latency. Reactivation may induce different organ manifestations, particularly in the setting of immunosuppression. Histopathologically, the virus can be detected by light microscopy. Different cell populations in different organs are transformed into"owl's eye" cells, which are pathognomonic. Immunohistochemistry and electron microscopy can be applied as complementary methods. Various PCR approaches in molecular pathology including nested PCR, capture probe ELISA-PCR and real time PCR confer HCMV tests high sensitivity and specificity. The present article discusses the methods of pathological diagnostic approaches and describes organ manifestations of HCMV.


Assuntos
Infecções por Citomegalovirus/patologia , Biópsia , Citomegalovirus/genética , Infecções por Citomegalovirus/congênito , Ensaio de Imunoadsorção Enzimática , Feminino , Genes Virais/genética , Humanos , Imuno-Histoquímica , Hibridização In Situ , Corpos de Inclusão Viral/patologia , Recém-Nascido , Microscopia Eletrônica , Infecções Oportunistas/patologia , Transplante de Órgãos , Reação em Cadeia da Polimerase , Complicações Pós-Operatórias/patologia , Gravidez , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Ativação Viral/fisiologia
6.
J Exp Med ; 185(4): 755-66, 1997 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-9034153

RESUMO

Soluble cytokine receptors modulate the activity of their cognate ligands. Interleukin (IL)-6 in association with the soluble IL-6 receptor (sIL-6R) can activate cells expressing the gp130 signal transducer lacking the specific IL-6R. To investigate the function of the IL-6-sIL-6R complex in vivo and to discriminate the function of the IL-6-sIL-6R complex from the function of IL-6 alone, we have established a transgenic mouse model. Double-transgenic mice coexpressing IL-6 and sIL-6R were generated and compared with IL-6 and sIL-6R single-transgenic mice. The main phenotype found in IL-6-sIL-6R mice was a dramatic increase of extramedullary hematopoietic progenitor cells in liver and spleen but not in the bone marrow. In IL-6 single-transgenic mice and sIL-6R single-transgenic mice no such effects were observed. The high numbers of hematopoietic progenitor cells were reflected by a strong increase of peripheral blood cell numbers. Therefore, activators of the gp130 signal transducer like the IL-6-IL-6R complex may represent most powerful stimulators for extramedullary hematopoietic progenitor cells. gp130 activators may become important for the expansion of hematopoietic progenitor cells in vivo and in vitro.


Assuntos
Células-Tronco Hematopoéticas/citologia , Interleucina-6/genética , Animais , Antígenos CD/metabolismo , Peso Corporal , Diferenciação Celular , Divisão Celular , Separação Celular , Receptor gp130 de Citocina , Citometria de Fluxo , Células-Tronco Hematopoéticas/metabolismo , Humanos , Imuno-Histoquímica , Fígado/patologia , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Tamanho do Órgão , Transdução de Sinais , Baço/patologia
7.
Br J Cancer ; 103(9): 1407-14, 2010 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-20924372

RESUMO

BACKGROUND: The combination of chemotherapy with the vascular endothelial growth factor (VEGF) antibody bevacizumab is a standard of care in advanced colorectal cancer (CRC). However, biomarkers predicting outcome of bevacizumab-containing treatment are lacking. As angiopoietin-2 (Ang-2) is a key regulator of vascular remodelling in concert with VEGF, we investigated its role as a biomarker in metastatic CRC. METHODS: Serum Ang-2 levels were measured in 33 healthy volunteers and 90 patients with CRC. Of these, 34 had metastatic disease and received bevacizumab-containing therapy. To determine the tissue of origin of Ang-2, quantitative real-time PCR was performed on microdissected cryosections of human CRC and in a murine xenograft model of CRC using species-specific amplification. RESULTS: Ang-2 originated from the stromal compartment of CRC tissues. Serum Ang-2 levels were significantly elevated in patients with metastatic CRC compared with healthy controls. Amongst patients receiving bevacizumab-containing treatment, low pre-therapeutic serum Ang-2 levels were associated with a significant better response rate (82 vs 31%; P<0.01), a prolonged median progression-free survival (14.1 vs 8.5 months; P<0.01) and a reduction of 91% in the hazard of death (P<0.05). CONCLUSION: Serum Ang-2 is a candidate biomarker for outcome of patients with metastatic CRC treated with bevacizumab-containing therapy, and it should be further validated to customise combined chemotherapeutic and anti-angiogenic treatment.


Assuntos
Angiopoietina-2/sangue , Anticorpos Monoclonais/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab , Biomarcadores Tumorais/sangue , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Cell Biol ; 126(2): 485-94, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8034747

RESUMO

Hepatocyte growth factor-scatter factor (HGF-SF) is a pleiotropic cytokine with mito-, morpho-, and motogenic effects on a variety of epithelial and endothelial cells. HGF-SF activity is mediated by the c-met protooncogene, a membrane-bound tyrosine kinase. Here, we demonstrate that both genes are expressed in developing and adult mammalian brains. HGF-SF mRNA is localized in neurons, primarily in the hippocampus, the cortex, and the granule cell layer of the cerebellum, and it is also present at high levels in ependymal cells, the chorioid plexus, and the pineal body. c-met is expressed in neurons, preferentially in the CA-1 area of the hippocampus, the cortex, and the septum, as well as in the pons. In the embryonic mouse, brain HGF-SF and c-met are expressed as early as days 12 and 13, respectively. Neuronal expression of HGF-SF is evolutionary highly conserved and detectable beyond the mammalian class. Incubation of septal neurons in culture with HGF-SF leads to a rapid increase of c-fos mRNA levels. The results demonstrate the presence of a novel growth factor-tyrosine kinase signaling system in the brain, and they suggest that HGF-SF induces a functional response in a neuronal subpopulation of developing and adult CNS.


Assuntos
Encéfalo/metabolismo , Fator de Crescimento de Hepatócito/biossíntese , Neurônios/metabolismo , RNA Mensageiro/análise , Receptores Proteína Tirosina Quinases/biossíntese , Animais , Sequência de Bases , Encéfalo/embriologia , Células Cultivadas , Desenvolvimento Embrionário e Fetal , Regulação da Expressão Gênica/efeitos dos fármacos , Fator de Crescimento de Hepatócito/análise , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/farmacologia , Humanos , Camundongos , Dados de Sequência Molecular , Fatores de Crescimento Neural/farmacologia , Neurônios/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met , RNA Mensageiro/genética , Ratos , Ratos Wistar , Receptores Proteína Tirosina Quinases/análise , Receptores Proteína Tirosina Quinases/genética , Proteínas Recombinantes/farmacologia , Transcrição Gênica
9.
Hum Gene Ther ; 30(10): 1284-1296, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31407607

RESUMO

Endothelial cells (EC) are targets in gene therapy and regenerative medicine, but they are inefficiently transduced with adeno-associated virus (AAV) vectors of various serotypes. To identify barriers hampering efficient transduction and to develop an optimized AAV variant for EC transduction, we screened an AAV serotype 2-based peptide display library on primary human macrovascular EC. Using a new high-throughput selection and monitoring protocol, we identified a capsid variant, AAV-VEC, which outperformed the parental serotype as well as first-generation targeting vectors in EC transduction. AAV vector uptake was improved, resulting in significantly higher transgene expression levels from single-stranded vector genomes detectable within a few hours post-transduction. Notably, AAV-VEC transduced not only proliferating EC but also quiescent EC, although higher particle-per-cell ratios had to be applied. Also, induced pluripotent stem cell-derived endothelial progenitor cells, a novel tool in regenerative medicine and gene therapy, were highly susceptible toward AAV-VEC transduction. Thus, overcoming barriers by capsid engineering significantly expands the AAV tool kit for a wide range of applications targeting EC.


Assuntos
Capsídeo/química , Dependovirus/genética , Engenharia Genética/métodos , Vetores Genéticos/química , Células Endoteliais da Veia Umbilical Humana/metabolismo , Transdução Genética/métodos , Sequência de Aminoácidos , Capsídeo/metabolismo , Diferenciação Celular , Dependovirus/metabolismo , Genes Reporter , Terapia Genética/métodos , Vetores Genéticos/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Células HeLa , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Biblioteca de Peptídeos
10.
Gene Ther ; 15(6): 443-51, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18004401

RESUMO

Targeted delivery of biological agents to atherosclerotic plaques may provide a novel treatment and/or useful tool for imaging of atherosclerosis in vivo. However, there are no known viral vectors that possess the desired tropism. Two plaque-targeting peptides, CAPGPSKSC (CAP) and CNHRYMQMC (CNH) were inserted into the capsid of adeno-associated virus 2 (AAV2) to assess vector retargeting. AAV2-CNH produced significantly higher levels of transduction than unmodified AAV2 in human, murine and rat endothelial cells, whereas transduction of nontarget HeLa cells was unaltered. Transduction studies and surface plasmon resonance suggest that AAV2-CNH uses membrane type 1 matrix metalloproteinase as a surface receptor. AAV2-CAP only produced higher levels of transduction in rat endothelial cells, possibly because the virus was found to be affected by proteasomal degradation. In vivo substantially higher levels of both peptide-modified AAV2 vectors was detected in the brachiocephalic artery (site of advanced atherosclerotic plaques) and aorta, whereas reduced levels were detected in all other organs examined. These results suggest that in the AAV2 platform the peptides are exposed on the capsid surface in a way that enables efficient receptor binding and so creates effective atherosclerotic plaque targeted vectors.


Assuntos
Aterosclerose/terapia , Dependovirus/genética , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Animais , Apolipoproteínas E/genética , Linhagem Celular , Dependovirus/metabolismo , Marcação de Genes , Engenharia Genética , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Heparina/metabolismo , Humanos , Metaloproteinase 1 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fragmentos de Peptídeos/genética , Ligação Proteica , Ratos , Ressonância de Plasmônio de Superfície , Transdução Genética/métodos , Transgenes
11.
Cancer Res ; 57(10): 2048-54, 1997 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-9158004

RESUMO

Previous investigations have supported or indicated a stimulatory role of the insulin-like growth factor II gene (IGF2) in hepatocarcinogenesis. We have studied the transcript levels, promoter usage, and imprinting status of the ICF2 gene and its relationship to H19 in human hepatocellular carcinomas (HCCs) and liver tumor cell lines. The activity of the IGF2 promoter P1 was lost in about 70% of the cases (18 of 25). This is the most prominent abnormality regarding the IGF2 regulation in this study. Total IGF2 as well as promoter P3 transcription were up-regulated in a small group of the tumors. Twenty genetically informative cases were obtained from 26 cases, thus excluding the probability of loss of heterozygosity of the IGF2 gene. Among these, nine showed abnormal monoallelic expression of IGF2. One HCC and one HCC cell line proved loss of functional imprinting of IGF2. H19 and IGF2 were regulated in parallel, and expression levels were variable. Taken together, the disruption of the IGF2 promoter regulation, particularly the loss of P1 activity, is a common feature of human HCCs. The loss of P1 activity explains the frequent loss of biallelic IGF2 expression and may potentially be used as a diagnostic or monitoring marker for human HCC.


Assuntos
Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento Insulin-Like II/genética , Neoplasias Hepáticas/genética , Regiões Promotoras Genéticas , RNA não Traduzido , Alelos , Carcinoma Hepatocelular/metabolismo , Éxons , Deleção de Genes , Expressão Gênica , Heterozigoto , Humanos , Fator de Crescimento Insulin-Like II/biossíntese , Neoplasias Hepáticas/metabolismo , Proteínas Musculares/biossíntese , Proteínas Musculares/genética , RNA Longo não Codificante , RNA Mensageiro/metabolismo
12.
Biochim Biophys Acta ; 1181(3): 266-72, 1993 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-8318551

RESUMO

In an attempt to investigate cellular fibronectin synthesis and deposition during acute liver damage and fibrogenesis, we used the presence of the additional type III-related ED-A domain of cellular fibronectin as a characteristic for distinguishing it from the plasma form. Using site-specific antibodies, we localized cellular fibronectin deposition in the necrotic pericentral areas of acutely damaged liver tissue after a single CCl4-gavage, whereas in control liver only trace amounts of cellular fibronectin were detectable along the sinusoids. Upon several CCl4-administrations leading to liver fibrosis, cellular fibronectin deposits were accumulated in the fibrotic septa. Northern blot hybridization using a cDNA representing part of the ED-A domain revealed that in liver tissue, in response to an acute intoxication, cellular fibronectin synthesis was initiated within the first 48 h after CCl4-gavage. By in situ hybridisation transcripts for cellular fibronectin were identified in the necrotic areas of acutely damaged tissue restricted to single, pericentrally located cells, whereas no cellular fibronectin mRNA was detectable in control liver. During fibrogenesis cellular fibronectin transcripts were shown to be synthesized in the immediate vicinity of septa. We conclude that upon acute or chronic intoxication, cellular fibronectin is a member of the accumulating biomatrix and is produced locally by mesenchymal liver cells.


Assuntos
Tetracloreto de Carbono/toxicidade , Fibronectinas/biossíntese , Cirrose Hepática Experimental/metabolismo , Fígado/efeitos dos fármacos , RNA Mensageiro/análise , Animais , Feminino , Fibronectinas/análise , Fígado/metabolismo , Fígado/patologia , Ratos , Ratos Wistar
13.
Cornea ; 24(1): 32-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15604864

RESUMO

PURPOSE: Low gas-permeable contact lens wear of polymethyl methacrylate or hydroxyethyl methacrylate material is known to cause morphologic abnormalities in the corneal endothelial cell layer. These lenses were widely prescribed and successfully worn until their use was actively discouraged in the late 1980s and early 1990s. This study was designed to investigate whether discontinuation of low gas-permeable contact lens wear leads to an improvement of corneal endothelial cell morphology. METHODS: At the time of discontinuation and at least 5 years after discontinuation of low gas-permeable contact lens wear, noncontact specular photographs of the central corneal endothelium were made in 66 patients (14 male and 52 female, mean age 37.7 +/- 8.4, range 24.6-69.0). By computer analysis of endothelial photographs, parameters for polymegethism and pleomorphism were calculated, as well as cell density. RESULTS: Mean follow-up time between photographs was 6.8 years (SD 1.1). Sixty-one patients were refitted with rigid high gas-permeable contact lenses or high-water-content soft lenses, and 5 patients switched to spectacle wear. A small but significant recovery of the corneal endothelial cell morphology was found for the mean coefficient of variation of cell area, from 37.5 to 35.7 (P = 0.022), and for the coefficient of variation of the number of sides, from 13.1 to 12.4 (P = 0.004). The mean percentage of hexagonal cells increased from 54.2 to 56.2 (P = 0.013). Although the corneal endothelial cell morphology improved significantly on cessation of LGP contact lens wear, the values did not return to levels observed in normal, non-contact lens wearing individuals. During follow-up, the mean endothelial cell density decreased significantly (P = 0.001) from 2994 to 2890 (a 3.5% cell loss in 6.8 years), which is similar to the known normal age-related cell loss of 0.6% per year in non-contact lens wearing healthy individuals. CONCLUSION: Endothelial polymegethism and pleomorphism caused by PMMA or HEMA contact lens wear is partly reversible.


Assuntos
Tamanho Celular , Lentes de Contato/estatística & dados numéricos , Endotélio Corneano/patologia , Adulto , Idoso , Contagem de Células , Feminino , Humanos , Masculino , Metacrilatos , Pessoa de Meia-Idade , Polimetil Metacrilato , Ajuste de Prótese , Estudos Retrospectivos , Suspensão de Tratamento
14.
Invest Ophthalmol Vis Sci ; 40(2): 312-9, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9950588

RESUMO

PURPOSE: To introduce a new model describing human in vivo corneal deswelling after hypoxic contact lens wear, based on a damped harmonic oscillator, which can describe an overshoot in corneal deswelling, to compare this new model with the currently used exponential model, and also to test whether a diurnal variation in baseline corneal thickness exists that would have to be taken into consideration when calculating corneal deswelling curves. METHODS: In nine healthy young adults, corneal thickness was measured every 30 minutes for 11.5 hours on average using modified optical pachometry (natural test). On another day, corneal deswelling was monitored for 11.1 hours on average after 2 hours of hypoxic contact lens wear (stress test). The damped harmonic oscillator model and the exponential model were used to calculate best-fitting deswelling curves. Natural test data were analyzed for the presence of a trend. Goodness of fit of the curves to the experimental data was analyzed using the F test. RESULTS: In 82% of the deswelling curves the new damped harmonic oscillator model provided a better fit to the data than the exponential model (P < 0.05). An average overshoot in corneal thickness recovery of 5 microm (range, 0-11 microm) was found. In 50% of the natural tests significant trends were found, without any consistent similarities. The overshoot could not be explained by these trends. CONCLUSIONS: The new damped harmonic oscillator model describes corneal deswelling after hypoxic contact lens wear more accurately than the exponential model. No consistent diurnal variation could be demonstrated.


Assuntos
Água Corporal/metabolismo , Córnea/metabolismo , Adulto , Ritmo Circadiano/fisiologia , Lentes de Contato , Córnea/anatomia & histologia , Feminino , Humanos , Umidade , Hipóxia/metabolismo , Masculino , Modelos Biológicos , Testes Visuais/instrumentação
15.
Invest Ophthalmol Vis Sci ; 35(7): 3071-7, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8206725

RESUMO

PURPOSE: To examine whether corneal hydration control is impaired in corneas with endothelial morphologic changes (increased variation in cell size and cell angularity) due to long-term low gas-permeable contact lens wear. METHODS: Twenty-one long-term wearers of low gas-permeable contact lenses (mean age, 41 years +/- 8 SD) and 18 age-matched controls (mean age, 42 years +/- 8 SD) were studied. To assess endothelial morphology, endothelial photographs were taken, enlarged 400X, scanned into a computer, and evaluated. Hydration control was assessed by a corneal stress test. Corneal swelling was induced by applying low gas-permeable soft contact lenses for 2 hours during eye closure. After the lenses were removed, the rate of deswelling was determined using optic pachometry. RESULTS: Morphologic analysis of the endothelial photographs showed a significant increase of polymegethism (P < 0.01) and pleomorphism (P < 0.01) in the group wearing contact lenses compared with the control group. The percentage of recovery of corneal thickness per hour (PRPH) from induced swelling proved to be significantly lower (P = 0.03) and the induced swelling proved to be significantly lower (P < 0.01) in the group wearing contact lenses than in the control group. Multiple regression analysis showed that the PRPH decreased as the morphologic alterations increased. However, this trend appeared not to be significant at the 5% level. A significant relationship was found between morphologic parameters and induced swelling, indicating that induced swelling decreased as the morphologic alterations increased. CONCLUSION: The results of this study indicate that increased endothelial polymegethism and pleomorphism may be accompanied by a decreased corneal hydration control in people who wear contact lenses.


Assuntos
Lentes de Contato Hidrofílicas/efeitos adversos , Endotélio Corneano/patologia , Endotélio Corneano/fisiopatologia , Adulto , Água Corporal/metabolismo , Lentes de Contato Hidrofílicas/estatística & dados numéricos , Córnea/patologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fotografação
16.
Invest Ophthalmol Vis Sci ; 41(11): 3286-92, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11006215

RESUMO

PURPOSE: Two mutations (R555Q and R124L) in the BIGH3 gene have been described in anterior or Bowman's layer dystrophies (CDB). The clinical, molecular, and ultrastructural findings of five families with CDB was reviewed to determine whether there is a consistent genotype:phenotype correlation. METHODS: Keratoplasty tissue from each patient was examined by light and electron microscopy (LM and EM). DNA was obtained, and exons 4 and 12 of BIGH3 were analyzed by polymerase chain reaction and single-stranded conformation polymorphism/heteroduplex analysis. Abnormally migrating products were analyzed by direct sequencing. RESULTS: In two families with type I CDB (CDBI), the R124L mutation was defined. There were light and ultrastructural features of superficial granular dystrophy and atypical banding of the "rod-shaped bodies" ultrastructurally. Patients from three families with "honeycomb" dystrophy were found to carry the R555Q mutation and had characteristic features of Bowman's dystrophy type II (CDBII). CONCLUSIONS: There is a strong genotype:phenotype correlation among CBDI (R124L) and CDBII (R555Q). LM and EM findings suggest that epithelial abnormalities may underlie the pathology of both conditions. The findings clarify the confusion over classification of the Bowman's layer dystrophies.


Assuntos
Distrofias Hereditárias da Córnea/genética , Distrofias Hereditárias da Córnea/patologia , Epitélio Corneano/ultraestrutura , Proteínas da Matriz Extracelular , Mutação , Proteínas de Neoplasias/genética , Fator de Crescimento Transformador beta/genética , Adulto , Membrana Basal/ultraestrutura , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Humanos , Lactente , Ceratoplastia Penetrante/patologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Acuidade Visual
17.
Biosens Bioelectron ; 19(12): 1723-31, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15142607

RESUMO

The labelfree detection of nucleic acid sequences is one of the modern attempts to develop quick, cheap and miniaturised hand-held devices for the future genetic testing in biotechnology and medical diagnostics. We present an approach to detect the hybridisation of DNA sequences using electrolyte-oxide-semiconductor field-effect transistors (EOSFETs) with micrometer dimensions. These semiconductor devices are sensitive to electrical charge variations that occur at the surface/electrolyte interface, i.e. upon hybridisation of oligonucleotides with complementary single-stranded (ss) oligonucleotides, which are immobilised on the oxide surface of the transistor gate. This method allows direct, time-resolved and in situ detection of specific nucleic acid binding events without any labelling. We focus on the detection mechanism of our sensors by using oppositely charged polyelectrolytes (PAH and PSS) subsequently attached to the transistor structures. Our results indicate that the sensor output is charge sensitive and distance dependent from the gate surface, which pinpoints the need for very defined surface chemistry at the device surface. The hybridisation of natural 19 base-pair sequences has been successfully detected with the sensors. In combination with nano-transistors a PCR free detection system might be feasible in future.


Assuntos
Técnicas Biossensoriais/instrumentação , Sondas de DNA/química , DNA/análise , Eletroquímica/instrumentação , Análise de Sequência com Séries de Oligonucleotídeos , Transdutores , Transistores Eletrônicos , Técnicas Biossensoriais/métodos , DNA/química , DNA/ultraestrutura , Sondas de DNA/ultraestrutura , Eletroquímica/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Coloração e Rotulagem , Propriedades de Superfície
18.
J Occup Environ Med ; 37(1): 59-68, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7620944

RESUMO

Point mutations in the p53 tumor suppressor gene are the most common genetic alterations in human cancers. The nature and location of these mutations can be informative in assessing the importance of putative carcinogenic agents. Potential associations between a given carcinogen and a specific mutation pattern can be substantiated when the exposure history of the patients is known. While the past exposure to environmental risk factors is often difficult to determine, documented occupational exposure to carcinogens presents a unique situation for evaluating this approach. Analysis usually involves working with paraffin-embedded tissues, fixed under conditions suboptimal for genetic analysis and stored for many years, since frozen tissues are not available in sufficient numbers. The particular methodological problems encountered with fixed samples are discussed here, using as illustration an ongoing study of oncogene and tumor suppressor gene mutations in archived bladder tumors of workers exposed to aromatic amines and nonexposed patients.


Assuntos
Carcinógenos/toxicidade , Análise Mutacional de DNA , Genes p53/genética , Exposição Ocupacional/efeitos adversos , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/genética , Sequência de Bases , DNA de Neoplasias/análise , Humanos , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase , Fatores de Risco , Neoplasias da Bexiga Urinária/epidemiologia
19.
Cell Death Dis ; 4: e586, 2013 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-23579273

RESUMO

Neuroblastoma is an embryonal malignancy of the sympathetic nervous system. Spontaneous regression and differentiation of neuroblastoma is observed in a subset of patients, and has been suggested to represent delayed activation of physiologic molecular programs of fetal neuroblasts. Homeobox genes constitute an important family of transcription factors, which play a fundamental role in morphogenesis and cell differentiation during embryogenesis. In this study, we demonstrate that expression of the majority of the human HOX class I homeobox genes is significantly associated with clinical covariates in neuroblastoma using microarray expression data of 649 primary tumors. Moreover, a HOX gene expression-based classifier predicted neuroblastoma patient outcome independently of age, stage and MYCN amplification status. Among all HOX genes, HOXC9 expression was most prominently associated with favorable prognostic markers. Most notably, elevated HOXC9 expression was significantly associated with spontaneous regression in infant neuroblastoma. Re-expression of HOXC9 in three neuroblastoma cell lines led to a significant reduction in cell viability, and abrogated tumor growth almost completely in neuroblastoma xenografts. Neuroblastoma growth arrest was related to the induction of programmed cell death, as indicated by an increase in the sub-G1 fraction and translocation of phosphatidylserine to the outer membrane. Programmed cell death was associated with the release of cytochrome c from the mitochondria into the cytosol and activation of the intrinsic cascade of caspases, indicating that HOXC9 re-expression triggers the intrinsic apoptotic pathway. Collectively, our results show a strong prognostic impact of HOX gene expression in neuroblastoma, and may point towards a role of Hox-C9 in neuroblastoma spontaneous regression.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , Regressão Neoplásica Espontânea/genética , Neoplasias do Sistema Nervoso/genética , Neuroblastoma/genética , Apoptose/genética , Caspases/genética , Caspases/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Pré-Escolar , Citocromos c/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Lactente , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteína Proto-Oncogênica N-Myc , Estadiamento de Neoplasias , Neoplasias do Sistema Nervoso/metabolismo , Neoplasias do Sistema Nervoso/mortalidade , Neoplasias do Sistema Nervoso/patologia , Neuroblastoma/metabolismo , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Prognóstico , Transdução de Sinais , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
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