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1.
Arch Gynecol Obstet ; 309(1): 211-218, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37789207

RESUMO

OBJECTIVES: Aim of this study is to estimate interobserver agreement in classifying adnexal tumors using IOTA terms, simple rules and subjective assessment. In addition, we related observers' accuracy with their experience in gynecological ultrasonography and the year of IOTA certification. METHODS: Eleven observers with three different levels of experience evaluated videoclips of 70 adnexal masses, defining tumor type according to IOTA terms and definitions, classifying the mass using IOTA Simple rules and Subjective assessment as well as providing Color Score evaluation. Sensitivity, specificity and area under the ROC curve were calculated and the year of IOTA certification was related with operators' accuracy through Pearson correlation coefficient. Interobserver agreement was estimated calculating percentage of agreement, Fleiss kappa and Cohen's kappa. RESULTS: We found a positive correlation between the year of IOTA certification and operators' accuracy (Pearson coefficient 0.694), especially among the observers with the least experience, the residents (p = 0.003). For tumor type classification, identification of papillary projections and classification of tumors using subjective assessment, agreement among all observers was moderate (Fleiss kappa 0.455, 0.552, and 0.476, respectively) and increased with the years of experience. Agreement in the application of Simple Rules was moderate in all examiners with IOTA certification, with Fleiss kappa in the range of (0.403, 0.498). For Color Score assignment interobserver agreement among all observers was fair (Cohen's kappa 0.380). CONCLUSIONS: Even among expert examiners, the results of adnexal lesion assessment can be inconsistent. Experience impacts on accuracy and agreement in subjective assessment, while the application of Simple Rules can mitigate the role of experience in interobserver agreement. The knowledge of IOTA models among residents seams to improve their diagnostic accuracy, showing the benefits of IOTA terminology for in training sonographers.


Assuntos
Doenças dos Anexos , Neoplasias , Neoplasias Ovarianas , Feminino , Humanos , Diagnóstico Diferencial , Variações Dependentes do Observador , Ultrassonografia , Curva ROC , Doenças dos Anexos/diagnóstico , Sensibilidade e Especificidade , Neoplasias Ovarianas/patologia
2.
J Physiol ; 595(16): 5525-5544, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28627017

RESUMO

KEY POINTS: The proton sensing ovarian cancer G protein coupled receptor 1 (OGR1, aka GPR68) promotes expression of the canonical transient receptor potential channel subunit TRPC4 in normal and transformed cerebellar granule precursor (DAOY) cells. OGR1 and TRPC4 are prominently expressed in healthy cerebellar tissue throughout postnatal development and in primary cerebellar medulloblastoma tissues. Activation of TRPC4-containing channels in DAOY cells, but not non-transformed granule precursor cells, results in prominent increases in [Ca2+ ]i and promotes cell motility in wound healing and transwell migration assays. Medulloblastoma cells not arising from granule precursor cells show neither prominent rises in [Ca2+ ]i nor enhanced motility in response to TRPC4 activation unless they overexpressTRPC4. Our results suggest that OGR1 enhances expression of TRPC4-containing channels that contribute to enhanced invasion and metastasis of granule precursor-derived human medulloblastoma. ABSTRACT: Aberrant intracellular Ca2+ signalling contributes to the formation and progression of a range of distinct pathologies including cancers. Rises in intracellular Ca2+ concentration occur in response to Ca2+ influx through plasma membrane channels and Ca2+ release from intracellular Ca2+ stores, which can be mobilized in response to activation of cell surface receptors. Ovarian cancer G protein coupled receptor 1 (OGR1, aka GPR68) is a proton-sensing Gq -coupled receptor that is most highly expressed in cerebellum. Medulloblastoma (MB) is the most common paediatric brain tumour that arises from cerebellar precursor cells. We found that nine distinct human MB samples all expressed OGR1. In both normal granule cells and the transformed human cerebellar granule cell line DAOY, OGR1 promoted expression of the proton-potentiated member of the canonical transient receptor potential (TRPC) channel family, TRPC4. Consistent with a role for TRPC4 in MB, we found that all MB samples also expressed TRPC4. In DAOY cells, activation of TRPC4-containing channels resulted in large Ca2+ influx and enhanced migration, while in normal cerebellar granule (precursor) cells and MB cells not derived from granule precursors, only small levels of Ca2+ influx and no enhanced migration were observed. Our results suggest that OGR1-dependent increases in TRPC4 expression may favour formation of highly Ca2+ -permeable TRPC4-containing channels that promote transformed granule cell migration. Increased motility of cancer cells is a prerequisite for cancer invasion and metastasis, and our findings may point towards a key role for TRPC4 in progression of certain types of MB.


Assuntos
Cálcio/metabolismo , Meduloblastoma/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Canais de Cátion TRPC/metabolismo , Animais , Sinalização do Cálcio , Linhagem Celular Tumoral , Movimento Celular , Células Cultivadas , Cerebelo/citologia , Humanos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Permeabilidade , Canais de Cátion TRPC/genética
3.
Phys Biol ; 13(6): 065001, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27845926

RESUMO

Information transfer is an essential factor in determining the robustness of biological systems with distributed control. The most direct way to study the mechanisms ruling information transfer is to experimentally observe the propagation across the system of a signal triggered by some perturbation. However, this method may be inefficient for experiments in the field, as the possibilities to perturb the system are limited and empirical observations must rely on natural events. An alternative approach is to use spatio-temporal correlations to probe the information transfer mechanism directly from the spontaneous fluctuations of the system, without the need to have an actual propagating signal on record. Here we test this method on models of collective behaviour in their deeply ordered phase by using ground truth data provided by numerical simulations in three dimensions. We compare two models characterized by very different dynamical equations and information transfer mechanisms: the classic Vicsek model, describing an overdamped noninertial dynamics and the inertial spin model, characterized by an underdamped inertial dynamics. By using dynamic finite-size scaling, we show that spatio-temporal correlations are able to distinguish unambiguously the diffusive information transfer mechanism of the Vicsek model from the linear mechanism of the inertial spin model.


Assuntos
Comportamento Animal , Modelos Teóricos , Análise Espaço-Temporal , Animais , Anisotropia , Aves , Simulação por Computador , Disseminação de Informação
4.
Nanotechnology ; 27(48): 485208, 2016 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-27819794

RESUMO

This work investigates titanium dioxide nanotube arrays (TiO2-NTA) grown by anodic oxidation as an active material for memristive applications. In particular, metal-insulator-metal structures made of vertically oriented amorphous TiO2-NTA grown on titanium foil were exploited in Ti/TiO2-NTA/Pt devices. The deposition of a polymeric thin film between NTA and top electrodes significantly improved the stability of the devices and increased by more than double the off/on resistance ratio. The resistive switching of TiO2-NTA samples crystallised by thermal annealing was also studied. Such devices displayed nonlinear I-V curves characterised by a smooth rectifying behaviour, without any evident resistive switching (RS). Also in this case, the interposition of the polymeric layer enhanced the RS behaviour of TiO2-NTA samples, remarkably increasing the devices' off/on ratio and endurance. The rise of high resistance states can be simply related to the addition of the polymer as resistance in series, while the variation of the low resistance states is here attributed to the occurrence of surface chemical reactions between polymer functional groups and the metal oxide, which increase the charge carriers available for conduction.

5.
Acta Biomed ; 94(4): e2023148, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37539603

RESUMO

BACKGROUND AND AIM: Iloprost is recommend worldwide for the treatment of RP and the healing of DUs. The aim of this study is to report the regimens of Iloprost administered in different rheumatological centers within the same regional Health System Methods: A questionnaire exploring different items related to the use of Iloprost was developed and reviewed by three expert rheumatologists. The questionnaire was distributed as an online survey to all local SSc referral centers in Emilia-Romagna (Italy). Data are reported as percentage or median with interquartile range (IQR), as appropriate. An updated review of world literature on this topic was also carried out. RESULTS: All the invited centers completed the survey. There were both local (8) and university hospitals (4). The majority (58%) had a rheumatologist as head physician. All centers used Iloprost: a single monthly administration was the most common treatment (75%). The cycle lasted 1 [IQR 1-2] days with a 0.5-2.0 ng/Kg/min dose according to the drug tolerance of the patients. There were overall 68 spots (beds, reclining armchair, or simple armchair); 2.0 [1.5-4.0] patients were able to receive Iloprost at the same time. University Hospitals had more physicians at their disposal than local hospitals but less paramedic personnel (respectively: 1.8 vs 1.2 physicians, 1.5 vs 2.1 nurses). CONCLUSIONS: These observations were in line with the majority of previous studies reporting different regimens, comparing similar (but not identical) dose and schedule administration, however, despite differences being at times substantial, no standard infusion method is yet available.


Assuntos
Iloprosta , Escleroderma Sistêmico , Humanos , Iloprosta/uso terapêutico , Iloprosta/efeitos adversos , Epoprostenol/uso terapêutico , Prostaglandinas I , Cicatrização , Inquéritos e Questionários , Escleroderma Sistêmico/tratamento farmacológico , Escleroderma Sistêmico/induzido quimicamente
6.
J Cell Physiol ; 227(6): 2798-803, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21938724

RESUMO

Imatinib (IM) is considered the gold standard for chronic myeloid leukemia (CML) treatment, although resistance is emerging as a significant problem. The proinflammatory cytokines interleukin-6 (IL-6) and interleukin-8 (IL-8) play an important role in cell proliferation, survival, and resistance to glucocorticoid-mediated cell death. Several transcription factors such as NF-KB and AP-1 are activated in response to physiopathological increases and modulation of intracellular calcium levels. Our previous study demonstrated that lymphocytes from CML patients showed dysregulated calcium homeostasis and oxidative stress. Alteration in ionized calcium concentration in the cytosol has been implicated in the initiation of secretion, contraction, and cell proliferation. In this study, we hypothesized that IL-6, IL-8, NF-kB, AP-1, and intracellular calcium may be used as selective and prognostic factors to address the follow-up in CML patients treated with imatinib. Our results demonstrated a significant down-regulation in IL-6 and IL-8 release as well as NF-kB and AP-1 activation in lymphomonocytes from Imatinib-treated patients, compared to samples from untreated patients. In parallel, IM treatment, in vivo and in vitro, were able to modulate the intracellular calcium concentration of peripheral blood mononuclear cells of CML patients by acting at the level of InsP(3) receptor in the endoplasmic reticulum and at the level of the purinergic receptors on plasma membrane. The results of this study show that measurements of NF-kB, AP-1, IL-6, IL-8, and intracellular calcium in CML patients treated with Imatinib may give important information to the hematologist on diagnostic criteria and are highly predictive in patients with newly diagnosed CML.


Assuntos
Antineoplásicos/uso terapêutico , Cálcio/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucócitos Mononucleares/efeitos dos fármacos , NF-kappa B/metabolismo , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Fator de Transcrição AP-1/metabolismo , Adulto , Benzamidas , Estudos de Casos e Controles , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Regulação para Baixo , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Feminino , Humanos , Mesilato de Imatinib , Receptores de Inositol 1,4,5-Trifosfato/efeitos dos fármacos , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Itália , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Leucócitos Mononucleares/enzimologia , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Receptores Purinérgicos/efeitos dos fármacos , Receptores Purinérgicos/metabolismo , Resultado do Tratamento
7.
Phys Rev E ; 106(5-1): 054404, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36559478

RESUMO

Adaptation is used by biological sensory systems to respond to a wide range of environmental signals, by adapting their response properties to the statistics of the stimulus in order to maximize information transmission. We derive rules of optimal adaptation to changes in the mean and variance of a continuous stimulus in terms of Bayesian filters and map them onto stochastic equations that couple the state of the environment to an internal variable controlling the response function. We calculate numerical and exact results for the speed and accuracy of adaptation and its impact on information transmission. We find that, in the regime of efficient adaptation, the speed of adaptation scales sublinearly with the rate of change of the environment. Finally, we exploit the mathematical equivalence between adaptation and stochastic thermodynamics to quantitatively relate adaptation to the irreversibility of the adaptation time course, defined by the rate of entropy production. Our results suggest a means to empirically quantify adaptation in a model-free and nonparametric way.

8.
Diagnostics (Basel) ; 13(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36611342

RESUMO

Metal components of hip prostheses cause severe artifacts in CT images, influencing diagnostic accuracy. Metal artifact reduction (MAR) software and virtual monoenergetic reconstructions on dual-energy CT (DECT) systems are possible solutions that should be considered. In this study, we created a customized adjustable phantom to quantify the severity of artifacts on periprosthetic tissues (cortical and spongious bone, soft tissues) for hip prostheses. The severity of artifacts was classified by different thresholds of deviation from the CT numbers for reference objects not affected by artifacts. The in vitro setup was applied on four unilateral and three bilateral configurations of hip prostheses (made of titanium, cobalt, and stainless steel alloys) with a DECT system, changing the energy of virtual monoenergetic reconstructions, with and without MAR. The impact of these tools on the severity of artifacts was scored, looking for the best scan conditions for the different configurations. For titanium prostheses, the reconstruction at 110 keV, without MAR, always minimized the artifacts. For cobalt and stainless-steel prostheses, MAR should always be applied, while monoenergetic reconstruction alone did not show clear advantages. The available tools for reducing metal artifacts must therefore be applied depending on the examined prosthetic configuration.

9.
Diagnostics (Basel) ; 12(9)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36140512

RESUMO

The aim of this study was the preliminary assessment of a new cationic contrast agent, the CA4+, via the analysis of spatial distribution in cartilage of ex vivo bovine samples, at micrometer and millimeter scale. Osteochondral plugs (n = 18) extracted from bovine stifle joints (n = 2) were immersed in CA4+ solution up to 26 h. Planar images were acquired at different time points, using a microCT apparatus. The CA4+ distribution in cartilage and saturation time were evaluated. Tibial plates from bovine stifle joints (n = 3) were imaged with CT, before and after 24 h-CA4+ bath immersion, at different concentrations. Afterward, potential CA4+ washout from cartilage was investigated. From microCT acquisitions, the CA4+ distribution differentiated into three distinct layers inside the cartilage, reflecting the spatial distribution of proteoglycans. After 24 h of diffusion, the iodine concentration reached in cartilage was approximately seven times that of the CA4+ bath. The resulting saturation time was 1.9 ± 0.9 h and 2.6 ± 2.9 h for femoral and tibial samples, respectively. Analysis of clinical CT acquisitions confirmed overall contrast enhancement of cartilage after 24 h immersion, observed for each CA4+ concentration. Distinct contrast enhancement was reached in different cartilage regions, depending on tissue's local features. Incomplete but remarkable washout of cartilage was observed. CA4+ significantly improved cartilage visualization and its qualitative analysis.

10.
Diagnostics (Basel) ; 11(12)2021 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-34943625

RESUMO

Cerebral venous outflow is investigated in the diagnosis of heart failure through the monitoring of jugular venous pulse, an indicator to assess cardiovascular diseases. The jugular venous pulse is a weak signal stemming from the lying internal jugular vein and often invasive methodologies requiring surgery are mandatory to detect it. Jugular venous pulse can also be extrapolated via the ultrasound technique, but it requires a qualified healthcare operator to perform the examination. In this work, a wireless, user-friendly, wearable device for plethysmography is developed to investigate the possibility of monitoring the jugular venous pulse non-invasively. The proposed device can monitor the jugular venous pulse and the electrocardiogram synchronously. To study the feasibility of using the proposed device to detect physiological variables, several measurements were carried out on healthy subjects by considering three different postures: supine, sitting, and upright. Data acquired in the experiment were properly filtered to highlight the cardiac oscillation and remove the breathing contribution, which causes a considerable shift in the amplitude of signals. To evaluate the proper functioning of the wearable device for plethysmography, a comparison with the ultrasound technique was carried out. As a satisfactory result, the acquired signals resemble the typical jugular venous pulse waveforms found in literature.

11.
Clin Chem ; 55(3): 541-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19147730

RESUMO

BACKGROUND: The determination of cellular beta-galactocerebrosidase activity is an established procedure to diagnose Krabbe disease and monitor the efficacy of gene/stem cell-based therapeutic approaches aimed at restoring defective enzymatic activity in patients or disease models. Current biochemical assays for beta-galactocerebrosidase show high specificity but generally require large protein amounts from scanty sources such as hematopoietic or neural stem cells. We developed a novel assay based on the hypothesis that specific measurements of beta-galactocerebrosidase activity can be performed following complete inhibition of beta-galactosidase activity. METHODS: We performed the assay using 2-7.5 microg of sample proteins with the artificial fluorogenic substrate 4-methylumbelliferone-beta-galactopyranoside (1.5 mmol/L) resuspended in 0.1/0.2 mol/L citrate/phosphate buffer, pH 4.0, and AgNO(3). Reactions were incubated for 30 min at 37 degrees C. Fluorescence of liberated 4-methylumbelliferone was measured on a spectrofluorometer (lambda(ex) 360 nm, lambda(em) 446 nm). RESULTS: AgNO(3) was a competitive inhibitor of beta-galactosidase [inhibition constant (K(i)) = 0.12 micromol/L] and completely inhibited beta-galactosidase activity when used at a concentration of 11 micromol/L. Under this condition, the beta-galactocerebrosidase activity was preserved and could be specifically and accurately measured. The assay can detect beta-galactocerebrosidase activity in as little as 2 microg cell protein extract or 7.5 microg tissue. Assay validation was performed using (a) brain tissues from wild-type and twitcher mice and (b) murine GALC(-/-) hematopoietic stem cells and neural precursor cells transduced by GALC-lentiviral vectors. CONCLUSIONS: The procedure is straightforward, rapid, and reproducible. Within a clinical context, our method unequivocally discriminated cells from healthy subjects and Krabbe patients and is therefore suitable for diagnostic applications.


Assuntos
Galactosilceramidase/análise , Galactosilceramidase/metabolismo , beta-Galactosidase/antagonistas & inibidores , beta-Galactosidase/metabolismo , Animais , Células Cultivadas , Cromatografia em Gel , Ativação Enzimática/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Nitrato de Prata/farmacologia , Técnicas de Cultura de Tecidos
12.
Biochem Pharmacol ; 166: 323-334, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31176618

RESUMO

The retinoblastoma RB1 gene has been identified in the 80s as the first tumor suppressor. RB1 loss of function, as well alterations in its pathway, occur in most human cancers and often have prognostic value. RB1 has a key role in restraining cell cycle entry and, along with its family members, regulates a myriad of cellular processes and affects cell response to a variety of stimuli, ultimately determining cell fate. Consistently, RB1 status is a crucial determinant of the cell response to antitumoral therapies, impacting on the outcome of both traditional and modern anti-cancer strategies, including precision medicine approaches, such as kinase inhibitors, and immunotherapy. Despite many efforts however, the predictive value of RB1 status in the clinical practice is still underused, mainly owing to the complexity of RB1 function, to differences depending on the cellular context and on the therapeutic strategies, and, not-lastly, to technical issues. Here, we provide an overview of studies analyzing the role of RB1 in response to conventional cytotoxic and cytostatic therapeutic agents in different cancer types, including hormone dependent ones. We also review RB1 predictive value in the response to the last generation CDK4/6 inhibitors, other kinase inhibitors, and immunotherapy and discuss new emerging non-canonical roles of RB1 that could impact on the response to antitumoral treatments.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Retina/metabolismo , Proteínas de Ligação a Retinoblastoma/metabolismo , Retinoblastoma/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Antineoplásicos/farmacologia , Humanos , Valor Preditivo dos Testes , Neoplasias da Retina/tratamento farmacológico , Neoplasias da Retina/genética , Retinoblastoma/tratamento farmacológico , Retinoblastoma/genética , Proteínas de Ligação a Retinoblastoma/genética , Ubiquitina-Proteína Ligases/genética
13.
Curr Pharm Des ; 19(30): 5327-32, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23394082

RESUMO

Normal cell cycle progression is controlled by the sequential action of cyclin-dependent kinases (CDKs), the activity of which depends on their binding to regulatory partners (cyclins). Deregulation of cell cycle is one of the first steps that transform normal cells into tumor cells. Indeed, most cancer cells bear mutations in members of the pathways that control the CDK activity. For this reason, this kinase family is a crucial target for the development of new drugs for cancer therapy. Recently, both ATP-competitive CDK inhibitors and the last generation of non-ATP-competitive inhibitors are emerging as promising agents for targeted therapies. Many clinical trials are in progress, using CDK inhibitors both as single agents and in combination with traditional cytotoxic agents. In this review, we will discuss new therapeutic strategies based on the use of CDK inhibitors in cancer.


Assuntos
Antineoplásicos/uso terapêutico , Quinases Ciclina-Dependentes/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Antineoplásicos/química , Quinases Ciclina-Dependentes/metabolismo , Desenho de Fármacos , Humanos , Estrutura Molecular
14.
Curr Genomics ; 11(7): 513-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21532835

RESUMO

Lung cancer is the leading cause of cancer deaths worldwide among both men and women, with more than 1 million deaths annually. Non-small cell lung cancer (NSCLC) accounts for about 80% of all lung cancers.Although recent advances have been made in diagnosis and treatment strategies, the prognosis of NSCLC patients is poor and it is basically due to a lack of early diagnostic tools.However, in the last years genetic and biochemical studies have provided more information about the protein and gene's mutations involved in lung tumors. Additionally, recent proteomic and microRNA's approaches have been introduced to help biomarker discovery.Here we would like to discuss the most recent discoveries in lung cancer pathways, focusing on the genetic and epigenetic factors that play a crucial role in malignant cell proliferation, and how they could be helpful in diagnosis and targeted therapy.

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