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1.
BJOG ; 128(8): 1353-1362, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33326680

RESUMO

OBJECTIVE: To evaluate partial HPV16/18 genotyping as a possible biomarker to select women attending HPV-based cervical cancer screening at higher risk to be referred to colposcopy. DESIGN: Population-based cohort study. SETTING: Organised cervical cancer screening programmes (Italy). POPULATION: Women with high-risk HPV infection (period: 2015-2019). METHODS: We analysed the association between partial HPV16/18 genotyping, cytology triage and histologically confirmed diagnosis of high-grade cervical intraepithelial neoplasia (CIN3+ ) lesions. MAIN OUTCOME MEASURES: Detection rate (DR) and positive predictive value (PPV) for histologically confirmed CIN3+ (any episode in the 2 years after baseline); sensitivity for CIN3+ and number of colposcopies needed for lesion detection. RESULTS: The study included 145 437 women screened with HPV testing by the clinically validated COBAS 4800 HPV assay (Roche). Overall, 9601 (6.6%) women were HPV+ at baseline; HPV16 and HPV18 were present in 1865 and 594 samples, respectively. The cumulative (baseline plus 1-year repeat) cytology positivity was 42.8% and high-grade cytology was significantly higher (P < 0.0001) among women with HPV16 infection at baseline (15.2%). The cumulative CIN3+ DR for women with HPV16, HPV18 and other HPV-type infections was 9.8%, 3.4% and 1.8%, respectively. CONCLUSIONS: Partial HPV16 genotyping may play a role in triage, whereas HPV18 seems to behave much more similarly to the other HPV types and does not provide additional stratification. HPV16 genotyping combined with high-grade cytology can be envisaged as a triage biomarker in cervical screening to maximise CIN3+ detection while minimising colposcopy at baseline or 1-year repeat. TWEETABLE ABSTRACT: HPV16 genotyping combined with high-grade cytology can be used as triage biomarker for CIN3+ in HPV-positive women.


Assuntos
Genótipo , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/virologia , Adulto , Idade de Início , Biomarcadores Tumorais , Colposcopia , Detecção Precoce de Câncer , Feminino , Técnicas Histológicas , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Humanos , Itália/epidemiologia , Programas de Rastreamento , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Gravidez , Fatores de Risco , Esfregaço Vaginal , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
2.
Redox Biol ; 13: 581-587, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28783588

RESUMO

Oxysterols are bioactive lipids that act as regulators of lipid metabolism, inflammation, cell viability and are involved in several diseases, including atherosclerosis. Mounting evidence linked the atherosclerosis to endothelium dysfunction; in fact, the endothelium regulates the vascular system with roles in processes such as hemostasis, cell cholesterol, hormone trafficking, signal transduction and inflammation. Several papers shed light the ability of oxysterols to induce apoptosis in different cell lines including endothelial cells. Apoptotic endothelial cell and endothelial denudation may constitute a critical step in the transition to plaque erosion and vessel thrombosis, so preventing the endothelial damaged has garnered considerable attention as a novel means of treating atherosclerosis. Endoplasmic reticulum (ER) is the site where the proteins are synthetized and folded and is necessary for most cellular activity; perturbations of ER homeostasis leads to a condition known as endoplasmic reticulum stress. This condition evokes the unfolded protein response (UPR) an adaptive pathway that aims to restore ER homeostasis. Mounting evidence suggests that chronic activation of UPR leads to cell dysfunction and death and recently has been implicated in pathogenesis of endothelial dysfunction. Autophagy is an essential catabolic mechanism that delivers misfolded proteins and damaged organelles to the lysosome for degradation, maintaining basal levels of autophagic activity it is critical for cell survival. Several evidence suggests that persistent ER stress often results in stimulation of autophagic activities, likely as a compensatory mechanism to relieve ER stress and consequently cell death. In this review, we summarize evidence for the effect of oxysterols on endothelial cells, especially focusing on oxysterols-mediated induction of endoplasmic reticulum stress.


Assuntos
Estresse do Retículo Endoplasmático , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Oxisteróis/metabolismo , Animais , Apoptose , Autofagia , Endotélio Vascular/citologia , Humanos , Resposta a Proteínas não Dobradas
3.
Eur J Neurol ; 24(10): 1283-1289, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28796376

RESUMO

BACKGROUND AND PURPOSE: We assessed the prevalence and magnitude of neuropsychiatric adverse events (NPAEs) associated with antiepileptic drugs (AEDs) among patients with brain tumour-related epilepsy (BTRE). METHODS: This observational, prospective, multicentre study enrolled 259 patients with BTRE after neurosurgery. All patients received AED monotherapy. Efficacy was assessed through clinical diaries, whereas NPAEs were collected using the Neuropsychiatric Inventory Test-12 questionnaire at baseline and after 5 months. RESULTS: Tumour localization in the frontal lobe was associated with a higher prevalence of NPAEs (odds ratio, 7.73; P < 0.001). Independent of tumour localization, levetiracetam (LVT) treatment was associated with higher prevalence and magnitude of NPAEs (odds ratio, 7.94; P < 0.01) compared with other AEDs. Patients with oligodendroglioma reported more NPAEs than patients with other tumour types. NPAEs were not influenced by chemotherapy, radiotherapy or steroid treatment. Evaluating non-neurobehavioural adverse events of AEDs, no significant differences were found among AEDs, although patients treated with old AEDs had a higher prevalence of adverse events than those treated with new AEDs. CONCLUSIONS: Both tumour localization in the frontal lobe and LVT treatment are associated with a higher risk of NPAEs in patients with BTRE. LVT is regarded as a first-line option in patients with BTRE because of easy titration and few significant drug-to-drug interactions. Thus, as NPAEs lead to poor compliance and a high dropout rate, clinicians need to accurately monitor NPAEs after AED prescription, especially in patients with frontal lobe tumours receiving LVT.


Assuntos
Anticonvulsivantes/efeitos adversos , Neoplasias Encefálicas/complicações , Epilepsia/tratamento farmacológico , Piracetam/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticonvulsivantes/uso terapêutico , Epilepsia/etiologia , Feminino , Humanos , Itália , Levetiracetam , Masculino , Pessoa de Meia-Idade , Piracetam/efeitos adversos , Piracetam/uso terapêutico , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
4.
Nucleus ; 7(2): 103-11, 2016 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-26930442

RESUMO

Nuclear lamins are the main components of the nuclear lamina at the nuclear periphery, providing mechanical support to the nucleus. However, recent findings suggest that lamins also reside in the nuclear interior, as a distinct and dynamic pool with critical roles in transcriptional regulation. In our work we found a functional and evolutionary conserved crosstalk between Lamin A/C and the Polycomb group (PcG) of proteins, this being required for the maintenance of the PcG repressive functions. Indeed, Lamin A/C knock-down causes PcG foci dispersion and defects in PcG-mediated higher order structures, thereby leading to impaired PcG mediated transcriptional repression. By using ad-hoc algorithms for image analysis and PLA approaches we hereby show that PcG proteins are preferentially located in the nuclear interior where they interact with nucleoplasmic Lamin A/C. Taken together, our findings suggest that nuclear components, such as Lamin A/C, functionally interact with epigenetic factors to ensure the correct transcriptional program maintenance.


Assuntos
Evolução Molecular , Lamina Tipo A/metabolismo , Proteínas do Grupo Polycomb/metabolismo , Transporte Ativo do Núcleo Celular , Diferenciação Celular , Núcleo Celular/metabolismo , Células HEK293 , Humanos , Mioblastos/citologia , Ligação Proteica
5.
Apoptosis ; 19(8): 1225-42, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24880782

RESUMO

Campylobacter jejuni is the most common cause of bacterial gastroenteritis in humans. The synthesis of cytolethal distending toxin appears essential in the infection process. In this work we evaluated the sequence of lethal events in HeLa cells exposed to cell lysates of two distinct strains, C. jejuni ATCC 33291 and C. jejuni ISS3. C. jejuni cell lysates (CCLys) were added to HeLa cell monolayers which were analysed to detect DNA content, death features, bcl-2 and p53 status, mitochondria/lysosomes network and finally, CD54 and CD59 alterations, compared to cell lysates of C. jejuni 11168H cdtA mutant. We found mitochondria and lysosomes differently targeted by these bacterial lysates. Death, consistent with apoptosis for C. jejuni ATCC 33291 lysate, occurred in a slow way (>48 h); concomitantly HeLa cells increase their endolysosomal compartment, as a consequence of toxin internalization besides a simultaneous and partial lysosomal destabilization. C. jejuni CCLys induces death in HeLa cells mainly via a caspase-dependent mechanism although a p53 lysosomal pathway (also caspase-independent) seems to appear in addition. In C. jejuni ISS3-treated cells, the p53-mediated oxidative degradation of mitochondrial components seems to be lost, inducing the deepest lysosomal alterations. Furthermore, CD59 considerably decreases, suggesting both a degradation or internalisation pathway. CCLys-treated HeLa cells increase CD54 expression on their surface, because of the action of lysate as its double feature of toxin and bacterial peptide. In conclusion, we revealed that C. jejuni CCLys-treated HeLa cells displayed different features, depending on the particular strain.


Assuntos
Campylobacter jejuni/metabolismo , Lisossomos/metabolismo , Mitocôndrias/metabolismo , Apoptose , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Cardiolipinas/metabolismo , Caspases/metabolismo , Citosol/metabolismo , Endocitose , Células HeLa , Humanos , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Lisossomos/ultraestrutura , Mitocôndrias/ultraestrutura , Mutação , Tetraspanina 30/metabolismo , Proteína Supressora de Tumor p53/metabolismo
6.
Rev Sci Instrum ; 84(3): 033904, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23556827

RESUMO

Great effort is currently being put into the development and construction of the second generation, advanced gravitational wave detectors, Advanced Virgo and Advanced LIGO. The development of new low thermal noise suspensions of mirrors, based on the experience gained in the previous experiments, is part of this task. Quasi-monolithic suspensions with fused silica wires avoid the problem of rubbing friction introduced by steel cradle arrangements by directly welding the wires to silica blocks bonded to the mirror. Moreover, the mechanical loss level introduced by silica (φfs ∼ 10(-7) in thin fused silica wires) is by far less than the one associated with steel. The low frequency dynamical behaviour of the suspension can be computed and optimized, provided that the wire bending shape under pendulum motion is known. Due to the production process, fused silica wires are thicker near the two ends (necks), so that analytical bending computations are very complicated. We developed a tool to directly measure the low frequency bending parameters of fused silica wires, and we tested it on the wires produced for the Virgo+ monolithic suspensions. The working principle and a set of test measurements are presented and explained.

7.
Rev Sci Instrum ; 82(9): 094502, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21974605

RESUMO

We report an application of Kalman filtering to the inverted pendulum (IP) of the Virgo gravitational wave interferometer. Using subspace method system identification techniques, we calculated a linear mechanical model of Virgo IP from experimental transfer functions. We then developed a Kalman filter, based on the obtained state space representation, that estimates from open loop time domain data, the state variables of the system. This allows the observation (and eventually control) of every resonance mode of the IP mechanical structure independently.

8.
Appl Opt ; 49(25): 4780-90, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20842804

RESUMO

In-vacuum Faraday isolators (FIs) are used in gravitational wave interferometers to prevent the disturbance caused by light reflected back to the input port from the interferometer itself. The efficiency of the optical isolation is becoming more critical with the increase of laser input power. An in-vacuum FI, used in a gravitational wave experiment (Virgo), has a 20 mm clear aperture and is illuminated by an almost 20 W incoming beam, having a diameter of about 5 mm. When going in vacuum at 10(-6) mbar, a degradation of the isolation exceeding 10 dB was observed. A remotely controlled system using a motorized lambda=2 waveplate inserted between the first polarizer and the Faraday rotator has proven its capability to restore the optical isolation to a value close to the one set up in air.

9.
Pathologica ; 102(1): 6-11, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20731248

RESUMO

The aim of this study was to assess the validity of protein p16 expression as an indicator of progression in lesions as ASC-US and L-SIL. For this purpose, we examined 246 cytological samples (91 ASC-US, 60 L-SIL, 36 ASC-H, 59 H-SIL) of which 151 were conventional Pap-tests (CC) and 95 in liquid based cytology (LBC) with colposcopic and histology follow-up. The results showed that in the positive p16 Pap-tests a 59% PPV vs CIN2+ in all cytologic diagnoses compared to 43% in cytologic reading alone. 96% of HG cytologic lesions were positive for p16, and the data showed good correlation between positivity for p16 in the cytologic preparations and the presence of CIN2+ lesions in the histologic test (chi-square for trend p < 0.0001). The sensitivity, specificity and NPV were 93%, 52% and 91%, respectively, in all cytologic diagnostic categories. P16 was positive in 46% of ASC-US and 53% of L-SIL. The PPV vs expressed CIN2+ was higher than that observed in cytologic reading (48% vs 26%, and 31% vs 20%, respectively). The sensitivity was 83%, the specificity 67% and 54%, respectively, and the VNP was 92% and 93%. It is possible to design algorithms for colposcopic follow-up that can reduce the need to obtain a follow-up. The future application of this test may allow the creation of a bio-molecular automated pap test.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Biomarcadores/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , Progressão da Doença , Feminino , Humanos , Gravidez , Reprodutibilidade dos Testes , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Esfregaço Vaginal , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/metabolismo , Displasia do Colo do Útero/patologia
10.
Rev Sci Instrum ; 80(5): 053904, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19485517

RESUMO

Loss angle measurements in ultralow mechanical loss materials is normally affected by a large systematic error due to the excess losses introduced by the suspension system used to hold the samples. Crystals such as sapphire and silicon or amorphous materials such as fused silica can have loss angles in the range of 10(-10)-10(-7); such materials are of extreme interest in the detection of small displacements as it is required in quantum measurements, frequency stabilization, Micro Electro-Mechanical Systems (MEMS), and gravitational wave research. In the system proposed here the sample is suspended in equilibrium on top of a sphere, touching on one of the nodal points of vibration. The advantage of this system, as compared to others used so far, is twofold: (i) one surface only of the sample is touched and the contact surface is minimized because of the absence of applied forces; (ii) some relevant parameters of the suspension can be measured and eventually varied, giving the experimentalist the possibility to identify whether the measured loss is limited by the suspension system in use or it is an intrinsic property of the sample under investigation. The measurements of a 75 mm diameter and 3 mm thickness disk of Suprasil 311 gave a loss angle phi of 5x10(-8).

11.
Appl Opt ; 47(31): 5853-61, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19122727

RESUMO

We describe a model evaluating changes in the optical isolation of a Faraday isolator when passing from air to vacuum in terms of different thermal effects in the crystal. The changes are particularly significant in the crystal thermal lensing (refraction index and thermal expansion) and in its Verdet constant and can be ascribed to the less efficient convection cooling of the magneto-optic crystal of the Faraday isolator. An isolation decrease by a factor of 10 is experimentally observed in a Faraday isolator that is used in a gravitational wave experiment (Virgo) with a 10 W input laser when going from air to vacuum. A finite element model simulation reproduces with a great accuracy the experimental data measured on Virgo and on a test bench. A first set of measurements of the thermal lensing has been used to characterize the losses of the crystal, which depend on the sample. The isolation factor measured on Virgo confirms the simulation model and the absorption losses of 0.0016 +/- 0.0002/cm for the TGG magneto-optic crystal used in the Faraday isolator.

13.
Experientia ; 39(9): 1030-1, 1983 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-6884491

RESUMO

Lead levels in the nervous system of rats intoxicated for 8 months by lead acetate (0.2% in drinking water) varied according to the region: the lowest levels were observed in sciatic nerve and the highest in hippocampus and cerebral neocortex, while intermediate levels were observed in pons medulla, cerebellum, midbrain, hypothalamus and striatum.


Assuntos
Chumbo/metabolismo , Sistema Nervoso/metabolismo , Animais , Peso Corporal , Eletroencefalografia , Feminino , Masculino , Ratos , Ratos Endogâmicos , Nervo Isquiático/metabolismo , Distribuição Tecidual
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