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1.
Food Res Int ; 186: 114337, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729718

RESUMO

A major concern for wineries is haze formation in white wines due to protein instability. Despite its prevalent use, the conventional bentonite method has shortcomings, including potential alteration of color and aroma, slow processing times, and notable wine wastage. Zirconium oxide (ZrO2) effectively removes proteins without affecting wine characteristics. However, producing cost-effective ZrO2 materials with efficient protein removal capabilities poses a significant challenge. This research aims to assess the viability of designing a porous material impregnated with zirconia to remove turbidity-causing proteins effectively. For this purpose, the support material alone (Al2O3) and the zirconia-impregnated support (ZrO2/Al2O3) were subjected to different calcination temperatures. It was observed that high-temperature treatments (750 °C) enhanced wine stability and protein adsorption capacity. The optimal adsorbent achieved a notable reduction in turbidity, decreasing the ΔNTU from 42 to 18, alongside a significant 44 % reduction in the total protein content, particularly affecting proteins in the molecular weight range of 10 to 70 kDa. This result is attributed to modifying the textural properties of ZrO2/Al2O3, characterized by the reduction of acidic sites, augmented pore diameters from 4.81 to 7.74 nm, and the emergence of zirconia clusters across the surface of the porous support. In summary, this study presents the first application of zirconia on the alumina support surface for protein stabilization in white wine. Combining ZrO2/Al2O3 and a high-temperature treatment emerges as a promising, cost-efficient, and environmentally sustainable strategy for protein removal in white wine.


Assuntos
Óxido de Alumínio , Vinho , Zircônio , Vinho/análise , Zircônio/química , Óxido de Alumínio/química , Adsorção , Estabilidade Proteica , Temperatura Alta , Manipulação de Alimentos/métodos
2.
Cell Rep ; 42(1): 112027, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36848231

RESUMO

TET2 haploinsufficiency is a driving event in myeloid cancers and is associated with a worse prognosis in patients with acute myeloid leukemia (AML). Enhancing residual TET2 activity using vitamin C increases oxidized 5-methylcytosine (mC) formation and promotes active DNA demethylation via base excision repair (BER), which slows leukemia progression. We utilize genetic and compound library screening approaches to identify rational combination treatment strategies to improve use of vitamin C as an adjuvant therapy for AML. In addition to increasing the efficacy of several US Food and Drug Administration (FDA)-approved drugs, vitamin C treatment with poly-ADP-ribosyl polymerase inhibitors (PARPis) elicits a strong synergistic effect to block AML self-renewal in murine and human AML models. Vitamin-C-mediated TET activation combined with PARPis causes enrichment of chromatin-bound PARP1 at oxidized mCs and γH2AX accumulation during mid-S phase, leading to cell cycle stalling and differentiation. Given that most AML subtypes maintain residual TET2 expression, vitamin C could elicit broad efficacy as a PARPi therapeutic adjuvant.


Assuntos
Leucemia , Inibidores de Poli(ADP-Ribose) Polimerases , Animais , Humanos , Camundongos , Ácido Ascórbico/farmacologia , Ácido Ascórbico/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Mutações Sintéticas Letais , Vitaminas
3.
Front Cell Infect Microbiol ; 12: 883759, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694548

RESUMO

The persistence of erythrocytes infected with Plasmodium falciparum gametocytes in the bloodstream is closely related to the modulation of their mechanical properties. New drugs that increase the stiffness of infected erythrocytes may thus represent a novel approach to block malaria parasite transmission. The phosphodiesterase inhibitor tadalafil has been shown to impair the ability of infected erythrocytes to circulate in an in vitro model for splenic retention. Here, we used a humanized mouse model to address in vivo the effect of tadalafil on the circulation kinetics of mature gametocyte-infected erythrocytes. We show that stiff immature gametocyte-infected erythrocytes are retained in the spleen of humanized mice at rates comparable to that of the in vitro model. Accordingly, tadalafil-induced stiffening of mature gametocyte-infected erythrocytes impairs their circulation in the bloodstream and triggers their retention by the spleen. These in vivo results validate that tadalafil is a novel drug lead potentially capable of blocking malaria parasite transmission by targeting GIE mechanical properties.


Assuntos
Malária Falciparum , Plasmodium falciparum , Animais , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Camundongos , Inibidores de Fosfodiesterase , Baço , Tadalafila/farmacologia
4.
Molecules ; 27(4)2022 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-35209041

RESUMO

The unstable proteins in white wine cause haze in bottles of white wine, degrading its quality. Thaumatins and chitinases are grape pathogenesis-related (PR) proteins that remain stable during vinification but can precipitate at high temperatures after bottling. The white wine protein stabilization process can prevent haze by removing these unstable proteins. Traditionally, bentonite is used to remove these proteins; however, it is labor-intensive, generates wine losses, affects wine quality, and harms the environment. More efficient protein stabilization technologies should be based on a better understanding of the main factors and mechanisms underlying protein precipitation. This review focuses on recent developments regarding the instability and removal of white wine proteins, which could be helpful to design more economical and environmentally friendly protein stabilization methods that better preserve the products´ quality.


Assuntos
Bentonita/química , Quitinases/química , Temperatura Alta , Proteínas de Plantas/química , Vitis , Vinho
5.
Commun Biol ; 3(1): 726, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33262483

RESUMO

To ensure the transport of nutrients necessary for their survival, Plasmodium falciparum parasites increase erythrocyte permeability to diverse solutes. These new permeation pathways (NPPs) have been extensively characterized in the pathogenic asexual parasite stages, however the existence of NPPs has never been investigated in gametocytes, the sexual stages responsible for transmission to mosquitoes. Here, we show that NPPs are still active in erythrocytes infected with immature gametocytes and that this activity declines along gametocyte maturation. Our results indicate that NPPs are regulated by cyclic AMP (cAMP) signaling cascade, and that the decrease in cAMP levels in mature stages results in a slowdown of NPP activity. We also show that NPPs facilitate the uptake of artemisinin derivatives and that phosphodiesterase (PDE) inhibitors can reactivate NPPs and increase drug uptake in mature gametocytes. These processes are predicted to play a key role in P. falciparum gametocyte biology and susceptibility to antimalarials.


Assuntos
Permeabilidade da Membrana Celular/fisiologia , Eritrócitos/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Estágios do Ciclo de Vida/fisiologia , Plasmodium falciparum/patogenicidade , Antimaláricos/farmacocinética , Artemisininas/farmacocinética , Células Cultivadas , AMP Cíclico/metabolismo , Humanos , Inibidores de Fosfodiesterase , Transdução de Sinais/fisiologia
6.
ACS Infect Dis ; 6(7): 1532-1547, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32267151

RESUMO

Three novel tracers designed as fluorescent surrogates of artemisinin-derived antimalarial drugs (i.e., dihydroartemisinin, artemether, arteether, and artemisone) were synthesized from dihydroartemisinin. One of these tracers, corresponding to a dihydroartemisinin/artemether/arteether mimic, showed a combination of excellent physicochemical and biological properties such as hydrolytic stability, high inhibitory potency against blood-stage parasites, similar ring-stage survival assay values than the clinical antimalarials, high cytopermeability and specific labeling of live P. falciparum cells, alkylation of heme, as well as specific covalent labeling of drug-sensitive and drug-resistant P. falciparum proteomes at physiological concentrations, consistent with a multitarget action of the drugs. Our study demonstrates that probes containing the complete structural core of clinical artemisinin derivatives can be stable in biochemical and cellular settings, and recapitulate the complex mechanisms of these frontline, yet threatened, antimalarial drugs.


Assuntos
Antimaláricos , Artemisininas , Antimaláricos/farmacologia , Artemeter , Artemisininas/farmacologia
7.
Sci Rep ; 8(1): 17886, 2018 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-30552367

RESUMO

Plasmodium falciparum gametocytes, the sexual stages responsible for malaria parasite transmission, develop in the human bone marrow parenchyma in proximity to the erythroblastic islands. Yet, mechanisms underlying gametocytes interactions with these islands are unknown. Here, we have investigated whether gametocyte-infected erythrocytes (GIE) adhere to erythroid precursors, and whether a putative adhesion may be mediated by a mechanism similar to the adhesion of erythrocytes infected with P. falciparum asexual stages to uninfected erythrocytes. Cell-cell adhesion assays with human primary erythroblasts or erythroid cell lines revealed that immature GIE do not specifically adhere to erythroid precursors. To determine whether adhesion may be dependent on binding of STEVOR proteins to Glycophorin C on the surface of erythroid cells, we used clonal lines and transgenic parasites that overexpress specific STEVOR proteins known to bind to Glycophorin C in asexual stages. Our results indicate that GIE overexpressing STEVOR do not specifically adhere to erythroblasts, in agreement with our observation that the STEVOR adhesive domain is not exposed at the surface of GIE.


Assuntos
Adesão Celular , Eritroblastos/fisiologia , Eritrócitos/fisiologia , Eritrócitos/parasitologia , Malária Falciparum/patologia , Plasmodium falciparum/crescimento & desenvolvimento , Antígenos de Protozoários/genética , Antígenos de Protozoários/metabolismo , Células Cultivadas , Humanos , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo
8.
J Exp Med ; 215(5): 1463-1480, 2018 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-29615469

RESUMO

Maintenance of genomic integrity is crucial for the preservation of hematopoietic stem cell (HSC) potential. Retrotransposons, spreading in the genome through an RNA intermediate, have been associated with loss of self-renewal, aging, and DNA damage. However, their role in HSCs has not been addressed. Here, we show that mouse HSCs express various retroelements (REs), including long interspersed element-1 (L1) recent family members that further increase upon irradiation. Using mice expressing an engineered human L1 retrotransposition reporter cassette and reverse transcription inhibitors, we demonstrate that L1 retransposition occurs in vivo and is involved in irradiation-induced persistent γH2AX foci and HSC loss of function. Thus, RE represents an important intrinsic HSC threat. Furthermore, we show that RE activity is restrained by thrombopoietin, a critical HSC maintenance factor, through its ability to promote a potent interferon-like, antiviral gene response in HSCs. This uncovers a novel mechanism allowing HSCs to minimize irradiation-induced injury and reinforces the links between DNA damage, REs, and antiviral immunity.


Assuntos
Antivirais/farmacologia , Citoproteção/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Retroelementos/genética , Trombopoetina/farmacologia , Animais , Citoproteção/efeitos da radiação , Dano ao DNA , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/efeitos da radiação , Humanos , Interferons/genética , Interferons/metabolismo , Elementos Nucleotídeos Longos e Dispersos/genética , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Radiação Ionizante , Fatores de Transcrição STAT/metabolismo
10.
Diagn Microbiol Infect Dis ; 86(3): 270-272, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27601381

RESUMO

Two-thirds of 152 patients treated for high-grade cervical disease, free of persistence/recurrence, and followed-up both with human papillomavirus (HPV) DNA testing and HPV genotyping cleared their high-risk HPV infection within 1year. Viral clearance continued at diminishing rates during the second and the third year, at the end of which it was virtually complete.


Assuntos
Carcinoma/tratamento farmacológico , Carcinoma/virologia , Papillomaviridae/isolamento & purificação , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/virologia , Adulto , Tratamento Conservador/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
11.
BMC Cancer ; 16: 680, 2016 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-27558259

RESUMO

BACKGROUND: Galectin-7 (Gal-7) is negatively regulated in cervical cancer, and appears to be a link between the apoptotic response triggered by cancer and the anti-tumoral activity of the immune system. Our understanding of how cervical cancer cells and their molecular networks adapt in response to the expression of Gal-7 remains limited. METHODS: Meta-analysis of Gal-7 expression was conducted in three cervical cancer cohort studies and TCGA. In silico prediction and bisulfite sequencing were performed to inquire epigenetic alterations. To study the effect of Gal-7 on cervical cancer, we ectopically re-expressed it in the HeLa and SiHa cervical cancer cell lines, and analyzed their transcriptome and SILAC-based proteome. We also examined the tumor and microenvironment host cell transcriptomes after xenotransplantation into immunocompromised mice. Differences between samples were assessed with the Kruskall-Wallis, Dunn's Multiple Comparison and T tests. Kaplan-Meier and log-rank tests were used to determine overall survival. RESULTS: Gal-7 was constantly downregulated in our meta-analysis (p < 0.0001). Tumors with combined high Gal-7 and low galectin-1 expression (p = 0.0001) presented significantly better prognoses (p = 0.005). In silico and bisulfite sequencing assays showed de novo methylation in the Gal-7 promoter and first intron. Cells re-expressing Gal-7 showed a high apoptosis ratio (p < 0.05) and their xenografts displayed strong growth retardation (p < 0.001). Multiple gene modules and transcriptional regulators were modulated in response to Gal-7 reconstitution, both in cervical cancer cells and their microenvironments (FDR < 0.05 %). Most of these genes and modules were associated with tissue morphogenesis, metabolism, transport, chemokine activity, and immune response. These functional modules could exert the same effects in vitro and in vivo, even despite different compositions between HeLa and SiHa samples. CONCLUSIONS: Gal-7 re-expression affects the regulation of molecular networks in cervical cancer that are involved in diverse cancer hallmarks, such as metabolism, growth control, invasion and evasion of apoptosis. The effect of Gal-7 extends to the microenvironment, where networks involved in its configuration and in immune surveillance are particularly affected.


Assuntos
Galectinas/metabolismo , Microambiente Tumoral/fisiologia , Neoplasias do Colo do Útero/metabolismo , Feminino , Humanos , Neoplasias do Colo do Útero/patologia
12.
Stem Cell Reports ; 6(6): 970-984, 2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27304919

RESUMO

The capacity of hematopoietic stem cells (HSC) to generate B lymphocytes declines with age, contributing to impaired immune function in the elderly. Here we show that the histone methyltransferase SUV39H1 plays an important role in human B lymphoid differentiation and that expression of SUV39H1 decreases with age in both human and mouse HSC, leading to a global reduction in H3K9 trimethylation and perturbed heterochromatin function. Further, we demonstrate that SUV39H1 is a target of microRNA miR-125b, a known regulator of HSC function, and that expression of miR-125b increases with age in human HSC. Overexpression of miR-125b and inhibition of SUV39H1 in young HSC induced loss of B cell potential. Conversely, both inhibition of miR-125 and enforced expression of SUV39H1 improved the capacity of HSC from elderly individuals to generate B cells. Our findings highlight the importance of heterochromatin regulation in HSC aging and B lymphopoiesis.


Assuntos
Envelhecimento/imunologia , Linfócitos B/citologia , Células-Tronco Hematopoéticas/citologia , Linfopoese/imunologia , Metiltransferases/genética , MicroRNAs/genética , Proteínas Repressoras/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Animais , Antagomirs/genética , Antagomirs/metabolismo , Linfócitos B/imunologia , Sequência de Bases , Diferenciação Celular , Feminino , Regulação da Expressão Gênica , Células-Tronco Hematopoéticas/imunologia , Heterocromatina/química , Heterocromatina/metabolismo , Humanos , Linfopoese/genética , Masculino , Metiltransferases/imunologia , Camundongos , MicroRNAs/antagonistas & inibidores , MicroRNAs/imunologia , Cultura Primária de Células , Proteínas Repressoras/imunologia , Transdução de Sinais
13.
J Lab Autom ; 21(3): 432-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25673634

RESUMO

Cervical specimens collected in liquid-based cytology (LBC) media are the most common sample type used for high-risk human papillomavirus (HPV) testing. Since preanalytic steps such as vortexing and decapping vials, liquid transfer to a sample input tube with matching unique identifier, and recapping the original vials are required for processing LBC samples prior to running the Abbott RealTime High Risk HPV assay (Abbott, Wiesbaden, Germany), a full manual execution can be complicated, especially in high-throughput diagnostic contexts. Here, a custom-configured worktable setup for the Tecan Freedom EVO (Tecan, Männedorf, Switzerland) designed to automate and control preanalytic steps for ThinPrep (Hologic, Marlborough, MA) samples was used to evaluate the impact of automated versus manual preanalytics. Archival results for manual processing of 226 samples were compared with those obtained with the Tecan protocol, observing a very good overall concordance for final assay interpretation (95.6%). High overall agreement (100%) resulted also from retesting 99 samples by both the preanalytical protocols. High reproducibility was observed analyzing 23 randomly selected samples by automated preprocessing in triplicate. Hence, the new configuration of the Tecan platform translates the manual steps required to process ThinPrep specimens into automated operations, controls sample identification, and allows for saving hands-on time, while maintaining assay reproducibility and ensuring reliability of results, making it suitable for screening settings.


Assuntos
Automação Laboratorial/métodos , Técnicas de Genotipagem/métodos , Papillomaviridae/classificação , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Manejo de Espécimes/métodos , Colo do Útero/virologia , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Papillomaviridae/isolamento & purificação , Reprodutibilidade dos Testes
14.
Biointerphases ; 10(2): 029519, 2015 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-25956181

RESUMO

Low power atmospheric pressure inductively coupled thermal plasma sources integrated with a quenching device (cold ICP) for the efficient production of biologically active agents have been recently developed for potential biomedical applications. In the present work, in vitro experiments aimed at assessing the decontamination potential of a cold ICP source were carried out on bacteria typically associated with chronic wounds and designed to represent a realistic wound environment; further in vitro experiments were performed to investigate the effects of plasma-irradiated physiological saline solution on eukaryotic cells viability. A thorough characterization of the plasma source and process, for what concerns ultraviolet (UV) radiation and nitric oxide production as well as the variation of pH and the generation of nitrates and nitrites in the treated liquid media, was carried out to garner fundamental insights that could help the interpretation of biological experiments. Direct plasma treatment of bacterial cells, performed at safe level of UV radiation, induces a relevant decontamination, both on agar plate and in physiological saline solution, after just 2 min of treatment. Furthermore, the indirect treatment of eukaryotic cells, carried out by covering them with physiological saline solution irradiated by plasma, in the same conditions selected for the direct treatment of bacterial cells does not show any noticeable adverse effect to their viability. Some considerations regarding the role of the UV radiation on the decontamination potential of bacterial cells and the viability of the eukaryotic ones will be presented. Moreover, the effects of pH variation, nitrate and nitrite concentrations of the plasma-irradiated physiological saline solution on the decontamination of bacterial suspension and on the viability of eukaryotic cells subjected to the indirect treatment will be discussed. The obtained results will be used to optimize the design of the ICP source for an effective production of reactive species, while keeping effluent temperature and UV radiation at values compatible with biomedical treatments.


Assuntos
Pressão Atmosférica , Desinfecção/métodos , Viabilidade Microbiana/efeitos da radiação , Gases em Plasma , Cloreto de Sódio/efeitos da radiação , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Eucarióticas/efeitos dos fármacos , Células Eucarióticas/fisiologia , Humanos , Cloreto de Sódio/química , Cloreto de Sódio/toxicidade , Raios Ultravioleta
15.
J Clin Virol ; 60(3): 243-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24845262

RESUMO

BACKGROUND: HPV16 is the most prevalent genotype in oropharyngeal squamous cell carcinomas (OPSCCs), but there are few information about intratype variants prevalence and their clinical relevance in these tumors. Moreover, since HPV DNA detection alone is not sufficient to determine a favorable prognosis for OPSCCs, additional diagnostic/prognostic biomarkers are necessary. OBJECTIVES: To assess the prevalence of HPV intratype variants and evaluate the role of HPV16 DNA methylation as prognostic marker in OPSCCs. STUDY DESIGN: We analyzed 81 biopsies of OPSCCs for HPV detection and genotyping with a pyrosequencing-based HPV DNA-test. We also quantified viral DNA methylation frequency in the LCR by pyrosequencing in patients with transcriptionally-active HPV16-infection, analyzing it in function of available clinical/virological data. RESULTS: The overall HPV prevalence was 74.1% and HPV16 was confirmed the most prevalent genotype (51/60, 85.0%). Interestingly, we detected, for the first time, HPV16 African variants in 10/51 cases (19.6%), pointing out their clinical relevance also out of the anogenital district. Regarding viral DNA methylation, the E2BS1 showed a significantly higher mean methylation frequency compared to E2BS3/4, as previously observed in high-grade precancerous lesions of the uterine cervix. On the other hand, patient with a mean methylation frequency in the early promoter >10% showed only a tendency to have a worse prognosis. CONCLUSIONS: Our results highlight both the involvement of HPV16 African variants in OPSCCs development and the necessity of further studies to deepen the role of viral methylation in these tumors, in order to better define similarities/differences compared to cervical cancer.


Assuntos
Carcinoma de Células Escamosas/virologia , Metilação de DNA , DNA Viral , Variação Genética , Papillomavirus Humano 16/genética , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Orofaríngeas/epidemiologia , Neoplasias Orofaríngeas/patologia , Infecções por Papillomavirus/complicações , Prevalência , Regiões Promotoras Genéticas , Fatores de Risco , Análise de Sobrevida
16.
Diagn Microbiol Infect Dis ; 79(2): 178-82, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24666707

RESUMO

Persistent infection with human papillomavirus (HPV) induces cervical cancer. Here, we describe a sensitive, specific, and rapid assay for high-risk HPV16 and 18 detection by isothermal helicase-dependent amplification. This method can be used as cost-effective diagnostic method for low-income countries, where highest incidences worldwide of cervical cancer are registered.


Assuntos
Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/virologia , Feminino , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Programas de Rastreamento/métodos , Sensibilidade e Especificidade , Temperatura
17.
Blood ; 123(4): 509-19, 2014 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-24184684

RESUMO

Loss of hematopoietic stem cell (HSC) function and increased risk of developing hematopoietic malignancies are severe and concerning complications of anticancer radiotherapy and chemotherapy. We have previously shown that thrombopoietin (TPO), a critical HSC regulator, ensures HSC chromosomal integrity and function in response to γ-irradiation by regulating their DNA-damage response. TPO directly affects the double-strand break (DSB) repair machinery through increased DNA-protein kinase (DNA-PK) phosphorylation and nonhomologous end-joining (NHEJ) repair efficiency and fidelity. This effect is not shared by other HSC growth factors, suggesting that TPO triggers a specific signal in HSCs facilitating DNA-PK activation upon DNA damage. The discovery of these unique signaling pathways will provide a means of enhancing TPO-desirable effects on HSCs and improving the safety of anticancer DNA agents. We show here that TPO specifically triggers Erk and nuclear factor κB (NF-κB) pathways in mouse hematopoietic stem and progenitor cells (HSPCs). Both of these pathways are required for a TPO-mediated increase in DSB repair. They cooperate to induce and activate the early stress-response gene, Iex-1 (ier3), upon DNA damage. Iex-1 forms a complex with pERK and the catalytic subunit of DNA-PK, which is necessary and sufficient to promote TPO-increased DNA-PK activation and NHEJ DSB repair in both mouse and human HSPCs.


Assuntos
Reparo do DNA , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Enzimológica da Expressão Gênica , Células-Tronco Hematopoéticas/citologia , Proteínas Imediatamente Precoces/metabolismo , NF-kappa B/metabolismo , Trombopoetina/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Antineoplásicos/química , Domínio Catalítico , Quebras de DNA de Cadeia Dupla , Dano ao DNA , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosforilação , Transdução de Sinais , Células-Tronco/citologia
18.
Diagn Microbiol Infect Dis ; 74(1): 43-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22717156

RESUMO

An accurate tool for viral typing is important for management of patients with human papillomavirus (HPV) infection and to monitor HPV vaccine efficacy. This study evaluated the performance of the HPV sign® Genotyping Test by analyzing 87 archival cervical specimens and compared results with historical data by INNO-LiPA HPV Genotyping Extra assay. There was a substantial concordance for HPV detection in clinical samples (k 0.66), with an overall agreement rate of 85.1%. The genotyping overall agreement, considering one by one the HPV infection detected, was 95.7%. The HPV sign test showed, however, lower sensitivity than INNO-LiPA for HPV 31, 53, and 66. On the other hand, The HPV16 sensitivity was higher for HPV sign (90.0%, confidence interval [CI] 0.79-1.01) than for INNO-LiPA (83.3%, CI 0.70-0.97). Furthermore, HPV sign allowed identifying the presence of HPV16 intratype variants. In conclusion, HPV sign is a promising method for HPV genotyping and has revealed advantages in detecting a broad spectrum of HPV types and variants.


Assuntos
Colo do Útero/virologia , Técnicas de Diagnóstico Molecular/métodos , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/diagnóstico , Virologia/métodos , Feminino , Genótipo , Humanos , Papillomaviridae/classificação , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Sensibilidade e Especificidade
19.
J Clin Virol ; 53(2): 121-4, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22115872

RESUMO

BACKGROUND: The Abbott RealTime High Risk HPV assay (ART) is an automated multiplex real-time PCR test for detection of DNA from 14 high risk (HR) HPV types in cervical specimens and simultaneous distinction of HPV16 and HPV18 from other HR-HPV. OBJECTIVES: To evaluate the performance of the ART assay in specimens referred for HPV testing to our laboratory (referral population) by comparison with historical data from HC2 and INNO-LiPA as well as histological status, if available. STUDY DESIGN: 412 cervical specimens were collected from women between 18 and 70 years of age: 301 previously tested by HC2 without clinical data and 111 previously tested by HC2 and INNO-LiPA with histological diagnosis of CIN3+. RESULTS: Our study demonstrated good overall agreement between ART, HC2 and INNO-LiPA. In the group of the CIN3+ specimens HR-HPV was detected by ART in 93.07% (95% CI: 88.12-98.02), while HR-HPV detection rates with HC2 and INNO-LiPA were 91.09% (95% CI: 85.53-96.65) and 95.05% (95% CI: 90.82-99.28), respectively. The typing capability of ART for HPV16, HPV18 and a pool of twelve other HR-HPV types was investigated by comparison with INNO-LiPA demonstrating high overall assay concordance (89.81%; k 0.87). CONCLUSIONS: The Abbott RealTime assay showed similar clinical performance for detection of CIN3+ compared with HC2. The high level of automation and ability to identify HPV16, HPV18 and other HR-HPV make this assay a very attractive option for HR-HPV testing, potentially improving patient management by risk stratification of cytological abnormal populations.


Assuntos
DNA Viral/análise , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Infecções por Papillomavirus/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/virologia , Adolescente , Adulto , Idoso , Colo do Útero/patologia , Colo do Útero/virologia , DNA Viral/genética , Feminino , Papillomavirus Humano 16/classificação , Papillomavirus Humano 18/classificação , Humanos , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular/métodos , Infecções por Papillomavirus/virologia , Kit de Reagentes para Diagnóstico , Encaminhamento e Consulta/estatística & dados numéricos , Reprodutibilidade dos Testes , Risco , Neoplasias do Colo do Útero/patologia , Adulto Jovem , Displasia do Colo do Útero/patologia
20.
Gynecol Oncol ; 124(3): 490-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22188786

RESUMO

OBJECTIVE: The present study assessed the clinical outcome of patients conservatively treated for cervical adenocarcinoma in situ (AIS) and their predictive factors using univariate and multivariate population averaged (PA) generalized estimating equation (GEE) model in a longitudinal setting. METHODS: A series of 166 consecutive women (mean age 39.8 yrs; range 23-63 yrs) underwent conservative treatment of AIS as the primary treatment and were followed-up (mean 40.9 mo) using colposcopy, PAP-smear, biopsy and HPV-testing with Hybrid Capture 2. RESULTS: Hysterectomy was performed as part of the primary management in 47 patients, who were excluded from the follow-up (FU) analysis. Out of 119 women closely followed-up, additional therapeutic procedures were performed in 69. At study conclusion, 7 patients (5.9%) showed persistent disease, while 8 (6.7%) had progressed to invasive adenocarcinoma (AC). Positive HR-HPV test was the only independent predictor of disease recurrence (adjusted OR=2.72; 95%CI 1.08-6.87), and together with free cone margins (OR=0.20; 95%CI 0.04-0.92), HR-HPV positivity was also the single most powerful predictor of disease progression to AC, with OR=3.74; 95%CI 1.84-7.61 (p=0.0001) in multivariate PA-GEE. CONCLUSIONS: These results suggest that testing HR-HPV positive at any time point during FU is the most significant independent predictor of progressive disease, while showing free margins in cone has a significant protective effect against progression to AC. Furthermore, because 4.3% women with persistent, recurrent or progressive disease experienced a late (5th and 6th FU) diagnosis of HG-CGIN or microinvasive AC, a close surveillance should be scheduled for at least three years in conservatively treated AIS patients.


Assuntos
Adenocarcinoma/cirurgia , Displasia do Colo do Útero/cirurgia , Neoplasias do Colo do Útero/cirurgia , Adenocarcinoma/patologia , Adulto , Conização , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Prognóstico , Resultado do Tratamento , Neoplasias do Colo do Útero/patologia , Adulto Jovem , Displasia do Colo do Útero/patologia
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