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1.
Strahlenther Onkol ; 194(6): 539-551, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29340706

RESUMO

BACKGROUND: The urokinase plasminogen activator system (uPA, uPAR, PAI­1) is upregulated in cancer and high plasma levels are associated with poor prognosis. Their interaction with hypoxia-related osteopontin (OPN) which is also overexpressed in malignant tumors suggests potential clinical relevance. However, the prognostic role of the uPA system in the radiotherapy (RT) of non-small-cell lung cancer (NSCLC), particularly in combination with OPN, has not been investigated so far. METHODS: uPA, uPAR, PAI­1 and OPN plasma levels of 81 patients with locally advanced or metastasized NSCLC were prospectively analyzed by ELISA before RT and were correlated to clinical patient/tumor data and prognosis after RT. RESULTS: uPAR plasma levels were higher in M1; uPA and PAI­1 levels were higher in M0 NSCLC patients. uPAR correlated with uPA (p < 0.001) which also correlated with PAI­1 (p < 0.001). The prognostic impact of OPN plasma levels in the RT of NSCLC was previously reported by our group. PAI­I plasma levels significantly impacted overall (OS) and progression-free survival (PFS). Low PAI­1 levels were associated with a significantly reduced OS and PFS with a nearly 2­fold increased risk of death (p = 0.029) and tumor progression (p = 0.029). In multivariate analysis, PAI­1 levels remained an independent prognostic factor for OS and PFS with a 3­fold increased risk of death (p = 0.001). If PAI­1 plasma levels were combined with OPN or tumor volume, we found an additive prognostic impact on OS and PFS with a 2.5- to 3­fold increased risk of death (p = 0.01). CONCLUSION: Our results suggest that PAI-1 but not uPA and uPAR might add prognostic information in patients with advanced NSCLC undergoing RT. High pretreatment PAI-1 plasma levels were found predominantly in M0-stage patients and indicate a favorable prognosis as opposed to OPN where high plasma levels are associated with poor survival and metastasis. In combination, PAI-1 and OPN levels successfully predicted outcome and additively correlated with prognosis. These findings support the notion of an antidromic prognostic impact of OPN and PAI-1 plasma levels in the RT of advanced NSCLC.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/radioterapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Quimiorradioterapia , Terapia Combinada , Ensaio de Imunoadsorção Enzimática , Humanos , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Osteopontina/sangue , Cuidados Paliativos , Inibidor 1 de Ativador de Plasminogênio/sangue , Prognóstico , Estudos Prospectivos , Receptores de Ativador de Plasminogênio Tipo Uroquinase/sangue , Estatística como Assunto , Pesquisa Translacional Biomédica , Carga Tumoral/fisiologia , Ativador de Plasminogênio Tipo Uroquinase/sangue
2.
Phys Rev Lett ; 118(14): 143901, 2017 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-28430470

RESUMO

We show that a temporal soliton can induce resonant radiation by three-wave mixing nonlinearities. This constitutes a new class of resonant radiation whose spectral positions are parametrically tunable. The experimental verification is done in a periodically poled lithium niobate crystal, where a femtosecond near-IR soliton is excited and resonant radiation waves are observed exactly at the calculated soliton phase-matching wavelengths via the sum- and difference-frequency generation nonlinearities. This extends the supercontinuum bandwidth well into the mid IR to span 550-5000 nm, and the mid-IR edge is parametrically tunable over 1000 nm by changing the three-wave mixing phase-matching condition. The results are important for the bright and broadband supercontinuum generation and for the frequency comb generation in quadratic nonlinear microresonators.

3.
Strahlenther Onkol ; 190(3): 276-82, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24322994

RESUMO

BACKGROUND: Hypoxic radioresistance plays a critical role in the radiotherapy of cancer and adversely impacts prognosis and treatment response. This prospective study investigated the interrelationship and the prognostic significance of several hypoxia-related proteins in non-small cell lung cancer (NSCLC) patients treated by radiotherapy ± chemotherapy. MATERIAL AND METHODS: Pretreatment osteopontin (OPN), vascular endothelial growth factor (VEGF) and carbonic anhydrase IX (CA IX) plasma levels were determined by ELISA in 55 NSCLC (M0) patients receiving 66 Gy curative-intent radiotherapy or chemoradiation. Marker correlation, association with clinicopathological parameters and the prognostic value of a biomarker combination was evaluated. RESULTS: All biomarkers were linearly correlated and linked to different clinical parameters including lung function, weight loss (OPN), gross tumor volume (VEGF) and T stage (CA IX). High OPN (p = 0.03), VEGF (p = 0.02) and CA IX (p = 0.04) values were significantly associated with poor survival. Double marker combination additively increased the risk of death by a factor of 2 and high plasma levels of the triple combination OPN/VEGF/CA IX yielded a 5.9-fold risk of death (p = 0.009). The combined assessment of OPN/VEGF/CA IX correlated independently with prognosis (p = 0.03) in a multivariate Cox regression model including N stage, T stage and GTV. CONCLUSION: This pilot study suggests that a co-detection augments the prognostic value of single markers and that the integration of OPN, VEGF and CA IX into a hypoxic biomarker profile for the identification of patients with largely hypoxic and radioresistant tumors should be further evaluated.


Assuntos
Antígenos de Neoplasias/sangue , Biomarcadores Tumorais/sangue , Anidrases Carbônicas/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Hipóxia/sangue , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/radioterapia , Osteopontina/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Idoso , Idoso de 80 Anos ou mais , Anidrase Carbônica IX , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Fracionamento da Dose de Radiação , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/mortalidade , Projetos Piloto , Prognóstico , Tolerância a Radiação , Estatística como Assunto , Taxa de Sobrevida , Resultado do Tratamento
4.
Sens Actuators A Phys ; 195: 154-159, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24672146

RESUMO

A plug-and-play CD-like platform is used to perform a statistical detection of platelet derived growth factor (PDGF) proteins through aptamer-based surface functionalization of multiple microcantilever arrays. When PDGF proteins bind to aptamer coatings, the cantilevers deflect. The deflection response is monitored by optical read-out units from a commercial DVD-ROM device. We report on the use of an improved sensing platform which facilitates measurements under continuous liquid flow and with temperature control. Also, the mechanical wobbling of the DVD-ROM platform has been minimized and the scanning system has been optimized in order to detect cantilever deflections in liquid with nanometer scale resolution. The capability of the sensing platform is demonstrated by detection of clinically relevant concentrations of PDGF proteins. We present statistical measurements on 100 microcantilevers at different concentrations of PDGF, ranging from 10 nM to 400 nM. Hereby it is possible to reliably characterize the averaged mechanical response of cantilevers as a function of protein concentration.

5.
Phys Rev Lett ; 109(4): 043902, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-23006089

RESUMO

Cascaded nonlinearities have attracted much interest, but ultrafast applications have been seriously hampered by the simultaneous requirements of being near phase matching and having ultrafast femtosecond response times. Here we show that in strongly phase-mismatched nonlinear frequency conversion crystals the pump pulse can experience a large and extremely broadband self-defocusing cascaded Kerr-like nonlinearity. The large cascaded nonlinearity is ensured through interaction with the largest quadratic tensor element in the crystal, and the strong phase mismatch ensures an ultrafast nonlinear response with an octave-spanning bandwidth. We verify this experimentally by showing few-cycle soliton compression with noncritical cascaded second-harmonic generation: Energetic 47 fs infrared pulses are compressed in a just 1-mm long bulk lithium niobate crystal to 17 fs (under 4 optical cycles) with 80% efficiency, and upon further propagation an octave-spanning supercontinuum is observed. Such ultrafast cascading is expected to occur for a broad range of pump wavelengths spanning the near- and mid-IR using standard nonlinear crystals.

6.
Int J Cancer ; 130(5): 1230-5, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21455991

RESUMO

Expression of microRNAs can affect age of tumor onset and prognosis of cancer patients. However, nothing is known about the effects of microRNAs on altered age of cancer onset and disease-specific survival of soft-tissue sarcoma (STS) patients. The levels of miR-210, also known as hypoxia-regulated microRNA, were analyzed by quantitative real-time (RT)-PCR in the tumors of 78 STS patients. The patients were stratified according to their microRNA levels with low, intermediate and high expression levels and the association of microRNA expression and patients' survival was analyzed using multivariate Cox's regression hazard analyses. A significant correlation between an intermediate miR-210 expression and disease-specific death of STS patients [relative risk (RR) = 3.19; p = 0.018] was observed compared with patients with high expression levels in their tumors. Interestingly, the association between an intermediate expression of miR-210 and a poor prognosis was only significant in female STS patients (RR = 11.28; p = 0.010), but not observed in male individuals. Furthermore, the expression of miR-210 showed a significant association with the age of tumor onset in a gender-specific manner. Specifically, male patients with an intermediate expression of miR-210 associated with a 9.6-year later age of tumor onset (p = 0.017) compared with males with a low expression of miR-210 in their tumors. However, no significant differences in the female patients were observed. This study provides the first evidence of a correlation of expression levels of a single microRNA (miR-210) with the prognosis and age of tumor onset in a gender-specific manner in STS patients.


Assuntos
Idade de Início , MicroRNAs/metabolismo , Sarcoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Sarcoma/mortalidade
7.
Opt Express ; 19(23): 22557-62, 2011 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-22109134

RESUMO

When ultrafast noncritical cascaded second-harmonic generation of energetic femtosecond pulses occur in a bulk lithium niobate crystal optical Cherenkov waves are formed in the near- to mid-IR. Numerical simulations show that the few-cycle solitons radiate Cherenkov (dispersive) waves in the λ = 2.2 - 4.5 µm range when pumping at λ1 = 1.2 - 1.8 µm. The exact phase-matching point depends on the soliton wavelength, and we show that a simple longpass filter can separate the Cherenkov waves from the solitons. The Cherenkov waves are born few-cycle with an excellent Gaussian pulse shape, and the conversion efficiency is up to 25%. Thus, optical Cherenkov waves formed with cascaded nonlinearities could become an efficient source of energetic near- to mid-IR few-cycle pulses.

8.
Br J Cancer ; 102(4): 731-7, 2010 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-20051950

RESUMO

BACKGROUND: The urokinase plasminogen activator (uPA) system is one of the best-investigated protease systems, both under physiological and pathological conditions, including various types of cancer. However, effects of co-expression of members of the uPA system in soft-tissue sarcoma (STS) patients at the protein level in both tumour tissue and serum have not been investigated yet. METHODS: We examined 82 STS patients for protein levels of uPA, PAI-1and uPAR in tumour tissue and serum by ELISA. RESULTS: A significant correlation between high antigen levels of uPA, PAI-1 or uPAR in tumour tissue, and of uPAR in serum, with poor outcome of STS patients was found for the first time. Most strikingly, we observed an additive effect of combined uPA, PAI-1 or uPAR levels in tumour tissue extracts with uPAR levels in serum on patients' prognosis. High uPA/uPAR, PAI-1/uPAR and uPAR/uPAR antigen levels in tumour tissue/serum were associated with a 5.9-fold, 5.8-fold and 6.2-fold increased risk of tumour-related death (P=0.003, 0.001 and 0.002, respectively) compared with those patients who displayed low levels of the respective marker combination. CONCLUSION: As expression of members of the uPA system in tumour tissue and serum is additively correlated with prognosis of STS patients, our results suggest that combinations of these biomarkers can identify STS patients with a higher risk of tumour-related death.


Assuntos
Inibidor 1 de Ativador de Plasminogênio/análise , Receptores de Ativador de Plasminogênio Tipo Uroquinase/análise , Sarcoma/diagnóstico , Ativador de Plasminogênio Tipo Uroquinase/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/metabolismo , Técnicas e Procedimentos Diagnósticos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Inibidor 1 de Ativador de Plasminogênio/sangue , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Prognóstico , Receptores de Ativador de Plasminogênio Tipo Uroquinase/sangue , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Sarcoma/sangue , Sarcoma/metabolismo , Sarcoma/mortalidade , Análise de Sobrevida , Ativador de Plasminogênio Tipo Uroquinase/sangue , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Adulto Jovem
9.
J Oral Pathol Med ; 39(4): 313-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19780905

RESUMO

BACKGROUND: This study investigates the prognostic impact of the expression of hypoxia-inducible factor 1alpha (Hif1alpha) and carbonic anhydrase IX (CAIX) detected by immunohistochemistry in oral squamous cell carcinoma (OSCC). METHODS: Statistical analysis of immunohistochemical results with clinical parameters including survival outcomes was performed for 80 OSCC patients. RESULTS: Patients with a low expression of both proteins survived on average 54.8 months, whereas those with an increased expression of Hif1alpha in their tumors combined with a low expression of CAIX survived on average only 37.6 months (P = 0.026). In multivariate Cox's regression hazard analysis, again patients with a low expression of Hif1alpha/CAIX had the best prognosis, whereas patients with increased Hif1alpha and low CAIX expression carried a 4.97-fold increased risk of tumor-related death (P = 0.042). CONCLUSION: A co-detection of low Hif1alpha/CAIX expression is significantly correlated with a better prognosis for OSCC patients, which may have implications for therapy options for these patients.


Assuntos
Antígenos de Neoplasias/análise , Anidrases Carbônicas/análise , Carcinoma de Células Escamosas/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Neoplasias Bucais/patologia , Anidrase Carbônica IX , Carcinoma de Células Escamosas/secundário , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Fatores Sexuais , Taxa de Sobrevida
10.
Diabetologia ; 52(2): 199-207, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19037628

RESUMO

OBJECTIVE: The incretin effect is attenuated in patients with type 2 diabetes mellitus, partly as a result of impaired beta cell responsiveness to glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1). The aim of the present study was to investigate whether 4 weeks of near-normalisation of the blood glucose level could improve insulin responses to GIP and GLP-1 in patients with type 2 diabetes. METHODS: Eight obese patients with type 2 diabetes with poor glycaemic control (HbA(1c) 8.6 +/- 1.3%), were investigated before and after 4 weeks of near-normalisation of blood glucose (mean blood glucose 7.4 +/- 1.2 mmol/l) using insulin treatment. Before and after insulin treatment the participants underwent three hyperglycaemic clamps (15 mmol/l) with infusion of GLP-1, GIP or saline. Insulin responses were evaluated as the incremental area under the plasma C-peptide curve. RESULTS: Before and after near-normalisation of blood glucose, the C-peptide responses did not differ during the early phase of insulin secretion (0-10 min). The late phase C-peptide response (10-120 min) increased during GIP infusion from 33.0 +/- 8.5 to 103.9 +/- 24.2 (nmol/l) x (110 min)(-1) (p < 0.05) and during GLP-1 infusion from 48.7 +/- 11.8 to 126.6 +/- 32.5 (nmol/l) x (110 min)(-1) (p < 0.05), whereas during saline infusion the late-phase response did not differ before vs after near-normalisation of blood glucose (40.2 +/- 11.2 vs 46.5 +/- 12.7 [nmol/l] x [110 min](-1)). CONCLUSIONS: Near-normalisation of blood glucose for 4 weeks improves beta cell responsiveness to both GLP-1 and GIP by a factor of three to four. No effect was found on beta cell responsiveness to glucose alone. CLINICALTRIALS.GOV ID NO.: NCT 00612950. FUNDING: This study was supported by The Novo Nordisk Foundation, The Medical Science Research Foundation for Copenhagen.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Polipeptídeo Inibidor Gástrico/farmacologia , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Adulto , Glicemia/efeitos dos fármacos , Peptídeo C/sangue , Jejum , Frutosamina/sangue , Polipeptídeo Inibidor Gástrico/administração & dosagem , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Hemoglobinas Glicadas/efeitos dos fármacos , Hemoglobinas Glicadas/metabolismo , Humanos , Infusões Intravenosas , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Valores de Referência
11.
Opt Express ; 16(5): 3273-87, 2008 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-18542415

RESUMO

We study cascaded quadratic soliton compressors and address the physical mechanisms that limit the compression. A nonlocal model is derived, and the nonlocal response is shown to have an additional oscillatory component in the nonstationary regime when the group-velocity mismatch (GVM) is strong. This inhibits efficient compression. Raman-like perturbations from the cascaded nonlinearity, competing cubic nonlinearities, higher-order dispersion, and soliton energy may also limit compression, and through realistic numerical simulations we point out when each factor becomes important. We find that it is theoretically possible to reach the single-cycle regime by compressing high-energy fs pulses for wavelengths lambda = 1.0-1.3 microm in a beta -barium-borate crystal, and it requires that the system is in the stationary regime, where the phase mismatch is large enough to overcome the detrimental GVM effects. however, the simulations show that reaching single-cycle duration is ultimately inhibited by competing cubic nonlinearities as well as dispersive waves, that only show up when taking higher-order dispersion into account.


Assuntos
Desenho Assistido por Computador , Compressão de Dados/métodos , Tecnologia de Fibra Óptica/instrumentação , Modelos Teóricos , Óptica e Fotônica/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Transdutores , Simulação por Computador
12.
Curr Med Chem ; 15(4): 322-38, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18288988

RESUMO

Poor oxygenation of solid tumors is a major indicator of adverse prognosis after standard treatment, e.g. radiotherapy. This observation founded on intratumoral pO(2) electrode measurements has been supported more recently by studies of injected hypoxia markers (pimonidazole, EF5) or hypoxia-related proteins (hypoxia-inducible factor-1alpha, carbonic anhydrase IX) detected immunohistochemically. Alternative approaches include imaging of tumor hypoxia by nuclear medicine studies and the measurement of hypoxia-related proteins (osteopontin) in patient plasma. Low oxygen levels as found in tumors are rarely observed in normal tissues. The presence of hypoxic tumor cells is therefore regarded not only as an adverse prognostic factor but as an opportunity for tumor-specific treatment. Classic approaches to normalize tumor oxygenation involve the breathing of modified gas mixtures and pharmacologic modification of blood flow as in the "accelerated radiotherapy, carbogen, nicotinamide" (ARCON) scheme. Specific killing of hypoxic tumor cells can potentially be achieved by hypoxia-selective cytotoxins (model substance tirapazamine), which has shown promise in head and neck cancer. Direct targeting of hypoxia-related molecules such as hypoxia-inducible factor-1alpha, the central regulator of the hypoxic response in tumor cells, is an attractive approach currently tested in preclinical models. For clinical applications, the appropriate combination of hypoxia detection for patient selection with a hypoxia-specific treatment is essential. A therapeutic benefit has been suggested for the selection of patients by plasma osteopontin level and treatment with the hypoxic radiosensitizer nimorazole in addition to radiotherapy, for selection by F-misonidazole positron-emission tomography (PET) and treatment with tirapazamine in addition to chemoradiation and for selection by pimonidazole immunohistochemistry and ARCON treatment, all in head and neck cancer.


Assuntos
Hipóxia/diagnóstico , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/radioterapia , Animais , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais , Eletrodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Hipóxia/diagnóstico por imagem , Hipóxia/genética , Hipóxia/metabolismo , Fator 1 Induzível por Hipóxia/efeitos dos fármacos , Neoplasias/diagnóstico por imagem , Neoplasias/genética , Osteopontina/biossíntese , Osteopontina/genética , Oxigênio/química , Tomografia por Emissão de Pósitrons , Radiossensibilizantes/farmacologia , Radiossensibilizantes/uso terapêutico
13.
Cancer Gene Ther ; 14(12): 994-1001, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17885676

RESUMO

The inhibitor of apoptosis wild-type survivin is a multifunctional protein that suppresses apoptosis and regulates cell cycle progression. An association between wild-type survivin expression and radiosensitivity has been described in different tumor cells. The effects of siRNA-induced knockdown of wild-type survivin and survivin-splice variants survivin-2B and survivin-Delta3 were investigated under normoxic and hypoxic conditions in the human sarcoma cell line US 8-93 (mutant p53). Inhibition of the survivin isoforms by siRNA resulted in a decrease of target mRNA down to 14-70% compared to cells treated with control siRNA independent of the oxygen level. The mRNA expression of survivin isoforms was decreased by the factor of 1-12 when the cells were cultivated under hypoxic conditions. Moreover, the knockdown of wild-type survivin reduced colony formation independent of oxygen concentration down to 70% and induced formation of polyploid cells. Less reduction of plating efficiency was observed after specific knockdown of survivin-2B and survivin-Delta3 under hypoxic or normoxic conditions. A knockdown of wild-type survivin, survivin-Delta3 and survivin-2B isoforms in combination with irradiation caused no radiosensitization in cell line US 8-93, neither under hypoxic nor under normoxic conditions tested in the colony-forming assay. However, knockdown of wild-type survivin caused radiosensitization in the megacolony assay.


Assuntos
Ciclo Celular/genética , Ciclo Celular/efeitos da radiação , Raios gama , Proteínas Associadas aos Microtúbulos/genética , Proteínas de Neoplasias/genética , Oxigênio/metabolismo , RNA Interferente Pequeno/genética , Tolerância a Radiação/genética , Sarcoma/genética , Hipóxia Celular/genética , Hipóxia Celular/efeitos da radiação , Linhagem Celular Tumoral , Humanos , Proteínas Inibidoras de Apoptose , Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/biossíntese , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/biossíntese , Sarcoma/metabolismo , Sarcoma/radioterapia , Survivina
14.
Opt Lett ; 32(17): 2490-2, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17767281

RESUMO

We study soliton pulse compression in materials with cascaded quadratic nonlinearities and show that the group-velocity mismatch creates two different temporally nonlocal regimes. They correspond to what is known as the stationary and nonstationary regimes. The theory accurately predicts the transition to the stationary regime, where highly efficient pulse compression is possible.

15.
Oncogene ; 26(50): 7170-4, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17525744

RESUMO

Cancer stem cells can play an important role in tumorigenesis and tumor progression. However, it is still difficult to detect and isolate cancer stem cells. An alternative approach is to analyse stem cell-associated gene expression. We investigated the coexpression of three stem cell-associated genes, Hiwi, hTERT and survivin, by quantitative real-time-PCR in 104 primary soft-tissue sarcomas (STS). Multivariate Cox's proportional hazards regression analyses allowed correlating gene expression with overall survival for STS patients. Coexpression of all three stem cell-associated genes resulted in a significantly increased risk of tumor-related death. Importantly, tumors of patients with the poorest prognosis were of all four tumor stages, suggesting that their risk is based upon coexpression of stem cell-associated genes rather than on tumor stage.


Assuntos
Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Sarcoma/genética , Sarcoma/patologia , Proteínas Argonautas , Feminino , Humanos , Proteínas Inibidoras de Apoptose , Masculino , Proteínas Associadas aos Microtúbulos/genética , Proteínas de Neoplasias/genética , Prognóstico , Proteínas/genética , Sarcoma/etiologia , Survivina , Telomerase/genética
16.
Oncogene ; 26(7): 1098-100, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-16953229

RESUMO

Self-renewal is considered as a common property of stem cells. Dysregulation of stem cell self-renewal is likely a requirement for the development of cancer. Hiwi, the human Piwi gene, encodes a protein responsible for stem cell self-renewal. In this study, we investigated the expression of Hiwi at the RNA level by real-time quantitative PCR in 65 primary soft-tissue sarcomas (STS) and ascertained its impact on prognosis for STS patients. In a multivariate Cox's proportional hazards regression model, we found that an increased expression of Hiwi mRNA is a significant negative prognostic factor for patients with STS (P=0.017; relative risk 4.6, 95% confidence interval (CI) 1.3-16.1) compared to medium expression of Hiwi transcript. However, a low expression of Hiwi transcript is correlated with a 2.4-fold (CI 0.7-8.0) increased risk, but this effect was not significant (P=0.17). Altogether, high-level expression of Hiwi mRNA identifies STS patients at high risk of tumour-related death. This is the first report showing a correlation between expression of a gene involved in stem cell self-renewal and prognosis of cancer patients.


Assuntos
Proteínas/genética , Sarcoma/mortalidade , Células-Tronco/metabolismo , Adulto , Proteínas Argonautas , Feminino , Humanos , Masculino , Prognóstico , Proteínas/metabolismo , RNA Mensageiro/biossíntese , Medição de Risco , Sarcoma/genética , Sarcoma/metabolismo , Sarcoma/patologia , Células-Tronco/patologia
17.
Phys Rev Lett ; 94(18): 183602, 2005 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15904368

RESUMO

High-resolution ghost image and ghost diffraction experiments are performed by using a single classical source of pseudothermal speckle light divided by a beam splitter. Passing from the image to the diffraction result solely relies on changing the optical setup in the reference arm, while leaving the object arm untouched. The product of spatial resolutions of the ghost image and ghost diffraction experiments is shown to overcome a limit which seemed to be achievable only with entangled photons.

18.
Phys Rev Lett ; 93(9): 093602, 2004 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-15447100

RESUMO

We consider a scheme for coherent imaging that exploits the classical correlation of two beams obtained by splitting incoherent thermal radiation. This case is analyzed in parallel with the configuration based on two entangled beams produced by parametric down-conversion, and a precise formal analogy is pointed out. This analogy opens the possibility of using classical beams from thermal radiation for ghost imaging schemes in the same way as entangled beams.

19.
Opt Express ; 12(24): 6067-81, 2004 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-19488248

RESUMO

In ghost imaging schemes information about an object is extracted by measuring the correlation between a beam that passed the object and a reference beam. We present a spatial averaging technique that substantially improves the imaging bandwidth of such schemes, which implies that information about high-frequency Fourier components can be observed in the reconstructed diffraction pattern. In the many-photon regime the averaging can be done in parallel and we show that this leads to a much faster convergence of the correlations. We also consider the reconstruction of the object image, and discuss the differences between a pixel-like detector and a bucket detector in the object arm. Finally, it is shown how to non-locally make spatial filtering of a reconstructed image. The results are presented using entangled beams created by parametric down-conversion, but they are general and can be extended also to the important case of using classically correlated thermal-like beams.

20.
Verh Dtsch Ges Pathol ; 88: 199-206, 2004.
Artigo em Alemão | MEDLINE | ID: mdl-16892553

RESUMO

The aim of this study was to determine the amplification status of the HDMX gene and the expression of the HDMX mRNA particularly that of the HDMX-S splice variant in soft tissue sarcomas (STS). We show that the HDMX gene is amplified in 27% of STSs, which was associated with a worse prognosis (RR = 2.8, p = 0.03). We have also found that the transcript of the HDMX-S variant was predominant in a subset of (14%) of tumor samples, which was correlated with a significantly decreased overall survival time (15 vs. 53 months, p < 0.0001, log-Rank-test) and with a 9-fold-increased risk of tumor-related death (p < 0.0001). There was no correlation between the HMDX gene amplification and the HDMX-S splice variant overexpression. In summary, our data indicate that both the overexpression of the HDMX-S transcript, as well as, the HDMX gene amplification are important prognostic markers for STS.


Assuntos
Amplificação de Genes , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas/genética , Sarcoma/genética , Processamento Alternativo , Proteínas de Ciclo Celular , Primers do DNA , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Marcadores Genéticos , Variação Genética , Humanos , Reação em Cadeia da Polimerase , Prognóstico , RNA Mensageiro/genética , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Sarcoma/mortalidade , Sarcoma/patologia , Análise de Sobrevida , Transcrição Gênica
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