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1.
Biomedicines ; 12(6)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38927417

RESUMO

Background: Although several prognostic factors for survival have been identified in glioblastoma, there are numerous other potential markers (such as hemoglobin) whose role has not yet been confirmed. The aim of this study was to evaluate a wide range of potential prognostic factors, including HIF-1α and hemoglobin levels, for survival in glioblastoma. A secondary aim was to determine whether hemoglobin levels were associated with HIF-1α expression. Methods: A retrospective study of 136 patients treated for glioblastoma at our institution between 2012 and 2021 was performed. Cox univariate and multivariate analyses were carried out. Kaplan-Meier survival curves were generated. In addition, bivariate non-parametric correlation analyses were performed for key variables. Results: Median survival was 11.9 months (range: 0-119.4). According to the univariate analysis, 13 variables were significantly associated with survival: age, performance status, extent of surgery, tumor depth, tumor size, epilepsy, postoperative chemoradiotherapy, IDH mutations, CD44, HIF-1α, HIF-1ß, vimentin, and PDFGR. According to the multivariate regression analysis, only four variables remained significantly associated with survival: age, extent of surgery, epilepsy, and HIF-1α expression. No significant association was observed between hemoglobin levels (low <120 g/L in females or <140 g/L in males vs. high ≥120 or ≥140 g/L) and survival or HIF-1α/HIF-1ß expression. Conclusions: In this retrospective study of patients with glioblastoma, four variables-age, extent of surgery, HIF-1α expression, and epilepsy-were significant prognostic factors for survival. Hemoglobin levels were not significantly associated with survival or HIF-1α expression. Although hypoxia is a well-recognized component of the glioblastoma microenvironment, more research is needed to understand the pathogenesis of onset tumor hypoxia and treatment implication.

2.
Beilstein J Nanotechnol ; 15: 190-198, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38352720

RESUMO

Graphene is one of the most extensively studied 2D materials, exhibiting extraordinary mechanical and electronic properties. Although many years have passed since its discovery, manipulating single graphene layers is still challenging using standard resist-based lithography techniques. Recently, it has been shown that it is possible to etch graphene directly in water-assisted processes using the so-called focused electron-beam-induced etching (FEBIE), with a spatial resolution of ten nanometers. Nanopatterning graphene with such a method in one single step and without using a physical mask or resist is a very appealing approach. During the process, on top of graphene nanopatterning, we have found significant morphological changes induced in the SiO2 substrate even at low electron dose values (<8 nC/µm2). We demonstrate that graphene etching and topographical changes in SiO2 substrates can be controlled via electron beam parameters such as dwell time and dose.

4.
Strahlenther Onkol ; 197(4): 288-295, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33067652

RESUMO

PURPOSE: To quantify mean heart dose (MHD) and doses to the left anterior descending artery (LAD) and left ventricle (LV) in a retrospective series of patients who underwent perioperative accelerated partial breast irradiation with multicatheter interstitial brachytherapy (MIB-APBI). METHODS: Sixty-eight patients with low-risk left breast cancer were treated with MIB-APBI at our institution between 2012 and 2017. Interstitial tubes were inserted during the tumorectomy and sentinel node biopsy and APBI was started 6 days later. The prescribed dose was 34 Gy in 10 fractions (twice a day) to the clinical target volume (CTV). The heart, LAD, and LV were contoured and the distance between each structure and the CTV was measured. The MHD, mean and maximum LAD doses (LAD mean/max), and mean LV doses (LV mean) were calculated and corrected to biologically equivalent doses in 2­Gy fractionation (EQD2). We also evaluated the impact of the distance between the cardiac structures and the CTV and of the volume receiving the prescribed dose (V100) and high-dose volume (V150) on heart dosimetry. RESULTS: Mean EQD2 for MHD, LAD mean/max, and mean LV were 0.9 ± 0.4 Gy (range 0.3-2.2), 1.6 ± 1.1 Gy (range, 0.4-5.6), 2.6 ± 1.9 Gy (range, 0.7-9.2), and 1.3 ± 0.6 Gy (range, 0.5-3.4), respectively. MHD, LAD mean/max, and LV mean significantly correlated with the distance between the CTV and these structures, but all doses were below the recommended limits (German Society of Radiation Oncology; DEGRO). The MHD and LV mean were significantly dependent on V100. CONCLUSION: Perioperative MIB-APBI resulted in low cardiac doses in our study. This finding provides further support for the value of this technique in well-selected patients with early-stage left breast cancer.


Assuntos
Braquiterapia/métodos , Neoplasias da Mama/radioterapia , Mama/efeitos da radiação , Coração/efeitos da radiação , Feminino , Humanos , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Estudos Retrospectivos
5.
Front Bioeng Biotechnol ; 8: 552357, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33344428

RESUMO

INTRODUCTION: Pulsed field ablation (PFA) exploits the delivery of short high-voltage shocks to induce cells death via irreversible electroporation. The therapy offers a potential paradigm shift for catheter ablation of cardiac arrhythmia. We designed an AC-burst generator and therapeutic strategy, based on the existing knowledge between efficacy and safety among different pulses. We performed a proof-of-concept chronic animal trial to test the feasibility and safety of our method and technology. METHODS: We employed 6 female swine - weight 53.75 ± 4.77 kg - in this study. With fluoroscopic and electroanatomical mapping assistance, we performed ECG-gated AC-PFA in the following settings: in the left atrium with a decapolar loop catheter with electrodes connected in bipolar fashion; across the interventricular septum applying energy between the distal electrodes of two tip catheters. After procedure and 4-week follow-up, the animals were euthanized, and the hearts were inspected for tissue changes and characterized. We perform finite element method simulation of our AC-PFA scenarios to corroborate our method and better interpret our findings. RESULTS: We applied square, 50% duty cycle, AC bursts of 100 µs duration, 100 kHz internal frequency, 900 V for 60 pulses in the atrium and 1500 V for 120 pulses in the septum. The inter-burst interval was determined by the native heart rhythm - 69 ± 9 bpm. Acute changes in the atrial and ventricular electrograms were immediately visible at the sites of AC-PFA - signals were elongated and reduced in amplitude (p < 0.0001) and tissue impedance dropped (p = 0.011). No adverse event (e.g., esophageal temperature rises or gas bubble streams) was observed - while twitching was avoided by addition of electrosurgical return electrodes. The implemented numerical simulations confirmed the non-thermal nature of our AC-PFA and provided specific information on the estimated treated area and need of pulse trains. The postmortem chest inspection showed no peripheral damage, but epicardial and endocardial discolorations at sites of ablation. T1-weighted scans revealed specific tissue changes in atria and ventricles, confirmed to be fibrotic scars via trichrome staining. We found isolated, transmural and continuous scars. A surviving cardiomyocyte core was visible in basal ventricular lesions. CONCLUSION: We proved that our method and technology of AC-PFA is feasible and safe for atrial and ventricular myocardial ablation, supporting their systematic investigation into effectiveness evaluation for the treatment of cardiac arrhythmia. Further optimization, with energy titration or longer follow-up, is required for a robust atrial and ventricular AC-PFA.

6.
Sci Rep ; 9(1): 11840, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31413275

RESUMO

For the first time, the combination of molecularly imprinted polymer (MIP) technology with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is presented with focus on an optimization of the LA-ICP-MS parameters such as laser beam diameter, laser beam fluence, and scan speed using CdS quantum dots (QDs) as a template and dopamine as a functional monomer. A non-covalent imprinting approach was employed in this study due to the simplicity of preparation. Simple oxidative polymerization of the dopamine that creates the self-assembly monolayer seems to be an ideal choice. The QDs prepared by UV light irradiation synthesis were stabilized by using mercaptosuccinic acid. Formation of a complex of QD-antibody and QD-antibody-antigen was verified by using capillary electrophoresis with laser-induced fluorescence detection. QDs and antibody were connected together via an affinity peptide linker. LA-ICP-MS was employed as a proof-of-concept for detection method of two types of immunoassay: 1) antigen extracted from the sample by MIP and subsequently overlaid/immunoreacted by QD-labelled antibodies, 2) complex of antigen, antibody, and QD formed in the sample and subsequently extracted by MIP. The first approach provided higher sensitivity (MIP/NIP), however, the second demonstrated higher selectivity. A mixture of proteins with size in range 10-250 kDa was used as a model sample to demonstrate the capability of both approaches for detection of IgG in a complex sample.


Assuntos
Compostos de Cádmio/química , Imunoensaio/métodos , Terapia a Laser , Espectrometria de Massas , Impressão Molecular , Polímeros/química , Proteínas/análise , Pontos Quânticos/química , Sulfetos/química , Animais , Eletroforese Capilar , Fluorescência , Imunoglobulina G/análise , Camundongos , Processamento de Sinais Assistido por Computador
7.
J Struct Biol ; 206(3): 345-348, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30965091

RESUMO

Macrofibrils, the main structural features within the cortical cells of mammalian hair shafts, are long composite bundles of keratin intermediate filaments (KIFs) embedded in a matrix of keratin-associated proteins. The KIFs can be helically arranged around the macrofibril central axis, making a cylinder within which KIF helical angle relative to macrofibril axis increases approximately linearly from macrofibril centre to edge. Mesophase-based self-assembly has been implicated in the early formation of macrofibrils, which first appear as liquid-crystal tactoids in the bulb of hair follicles. Formation appears to be driven initially by interactions between pre-keratinized KIFs. Differences in the nature of these KIF-KIF interactions could result in all macrofibrils being internally twisted in a single handedness, or a 50:50 mixture of handedness within each cortical cell. We data-mined 41 electron tomograms containing three-dimensional macrofibril data from previously published studies of hair and wool. In all 644 macrofibrils examined we found that within each tomogram all macrofibrils had the same handedness. We concluded that earlier reports of left- and right-handed macrofibrils were due to artefacts of imaging or data processing. A handedness marker was used to confirm (using re-imaged sections from earlier studies) that, in both human and sheep, all macrofibrils are left-handed around the macrofibril axis. We conclude that this state is universal within mammalian hair. This also supports the conclusion that the origin of macrofibril twist is the expression of chiral twisting forces between adjacent KIFs, rather than mesophase splay and bending forces relaxing to twisting forces acting within a confined space.


Assuntos
Citoesqueleto/ultraestrutura , Cabelo/ultraestrutura , Filamentos Intermediários/ultraestrutura , Queratinas/ultraestrutura , Animais , Citoesqueleto/química , Tomografia com Microscopia Eletrônica , Cabelo/química , Humanos , Filamentos Intermediários/química , Queratinas/química , Ovinos/genética , Lã/química , Lã/ultraestrutura
8.
Chem Commun (Camb) ; 55(8): 1088-1091, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30620024

RESUMO

We report successful grafting of alkynyl groups onto graphene via the Sonogashira reaction between fluorographene and terminal alkynes. Theoretical calculations revealed that fluorographene can efficiently bind and oxidize the palladium catalyst on electrophilic sites activated by fluorine atoms. This paves the way towards conductive and mechanically robust 3D covalent networks.

9.
Indian J Med Res ; 144(2): 229-237, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27934802

RESUMO

BACKGROUND & OBJECTIVES: Heat shock proteins (Hsp) are ubiquitously distributed phylogenetically conserved molecules that regulate cellular homeostasis and maintain the integrity and function of cellular proteins. Increased levels of Hsp in maternal circulation have been shown to be associated with increased risk of pregnancy related complications. The objective of this study was to explore extracellular Hsp mRNA levels in maternal circulation and quantified Hsp27, Hsp60, Hsp70, Hsp90 and Hsp70 binding protein 1 (HspBP1) mRNAs in maternal plasma samples using real-time reverse-transcriptase polymerase chain reaction. METHODS: Pregnancies with gestational hypertension (GH) (n = 33), pre-eclampsia (PE) with or without foetal growth restriction (FGR) (n = 78) and FGR (n = 25) were involved in the study. Hsp gene expression was analysed in relation to the severity of the disease with respect to the degree of clinical signs, requirements for the delivery and Doppler ultrasound parameters. RESULTS: Upregulation of Hsp70 was observed in patients with mild and severe PE (P = 0.004 and P = 0.005, respectively) and in pregnancies complicated with PE delivering before and after 34 wk of gestation regardless of the degree of clinical signs (P = 0.015 and P = 0.009, respectively). No difference in the expression of other Hsp genes among the studied groups was observed. No association between Hsp gene expression and Doppler ultrasonography parameters was found. INTERPRETATION & CONCLUSIONS: These data support that maternal circulation can reflect both maternal and foetal pathologic conditions. Hsp70 represents the sole plasmatic marker, and increased Hsp70 mRNA levels reflect maternal and placental stress response to pregnancy-related complications such as GH and PE, irrespective of the severity of the disease.


Assuntos
Proteínas de Choque Térmico HSP70/sangue , Hipertensão Induzida pela Gravidez/sangue , Pré-Eclâmpsia/patologia , Complicações na Gravidez/sangue , Adulto , Pressão Sanguínea , Feminino , Retardo do Crescimento Fetal/sangue , Retardo do Crescimento Fetal/patologia , Proteínas de Choque Térmico HSP70/biossíntese , Humanos , Hipertensão Induzida pela Gravidez/patologia , Placenta/patologia , Pré-Eclâmpsia/sangue , Gravidez , Complicações na Gravidez/patologia , RNA Mensageiro/biossíntese , RNA Mensageiro/sangue
10.
DNA Cell Biol ; 34(6): 437-57, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25825993

RESUMO

To demonstrate that pregnancy-related complications are associated with alterations in placental microRNA expression. Gene expression of 15 C19MC microRNAs (miR-512-5p, miR-515-5p, miR-516-5p, miR-517-5p, miR-518b, miR-518f-5p, miR-519a, miR-519d, miR-519e-5p, miR-520a-5p, miR-520h, miR-524-5p, miR-525, miR-526a, and miR-526b) was assessed in placental tissues, compared between groups (21 gestational hypertension [GH], 63 preeclampsia, 36 fetal growth restriction [FGR], and 42 normal pregnancies), and correlated with the severity of the disease with respect to clinical signs, delivery date, and Doppler ultrasound parameters. The expression profile of microRNAs was different between pregnancy-related complications and controls. The downregulation of 4 of 15 (miR-517-5p, miR-519d, miR-520a-5p, and miR-525), 6 of 15 (miR-517-5p, miR-518f-5p, miR-519a, miR-519d, miR-520a-5p, and miR-525), and 11 of 15 (miR-515-5p, miR-517-5p, miR-518b, miR-518f-5p, miR-519a, miR-519d, miR-520a-5p, miR-520h, miR-524-5p, miR-525, and miR-526a) microRNAs was associated with GH, FGR, and preeclampsia, respectively. Sudden onset of severe preeclampsia requiring immediate termination of gestation and mild forms of preeclampsia (persisting for several weeks) were associated with similar microRNA expression profile (downregulation of miR-517-5p, miR-520a-5p, miR-524-5p, and miR-525). In addition, miR-519a was found to be associated with severe preeclampsia. The longer the pregnancy-related disorder lasted, the more extensive was the downregulation of microRNAs (miR-515-5p, miR-518b, miR-518f-5p, miR-519d, and miR-520h). The downregulation of some C19MC microRNAs is a common phenomenon shared between GH, preeclampsia, and FGR. On the other hand, some of the C19MC microRNAs are only downregulated just in preeclampsia.


Assuntos
Retardo do Crescimento Fetal/metabolismo , Hipertensão Induzida pela Gravidez/metabolismo , MicroRNAs/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Adulto , Biomarcadores/metabolismo , Cromossomos Humanos Par 19/genética , Feminino , Humanos , Masculino , MicroRNAs/genética , Família Multigênica , Gravidez , Estudos Retrospectivos , Transcriptoma , Adulto Jovem
11.
Mol Biol Rep ; 42(3): 625-37, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25359312

RESUMO

The study describes the stress response in the central cotyledon zone of placental tissue and in maternal whole peripheral blood to pregnancy related complications including gestational hypertension (n = 31), preeclampsia w or w/o fetal growth restriction (n = 95), and fetal growth restriction (n = 39) using real-time RT-PCR and genes encoding Hsp27, Hsp60, Hsp70, Hsp90 and HspBP1 proteins. The placental tissue does not respond to pregnancy induced hypertension, fetal growth restriction and short-term severe preeclampsia that requires immediate termination of gestation. Upregulation of Hsp27, Hsp90 and HspBP1 appears just in case of long-term deteriorated conditions (usually in mild preeclampsia, that enable further continuation of gestation, when properly treated). On the other hand, maternal circulation is able to reflect both maternal and fetal pathologic conditions. While pregnancy related complications always induce upregulation of Hsp70 and downregulation of Hsp90 in maternal whole peripheral blood, the increase of Hsp60 mRNA levels occurs entirely in patients with preeclampsia and/or fetal growth restriction. Hsp60, Hsp70 and Hsp90 are dysregulated in maternal circulation irrespective of the severity of the disease (in both mild and severe preeclampsia) and the requirements for the delivery (before and after 34th week of gestation). Nevertheless, the highest Hsp60 mRNA levels may be observed in pregnancies with signs of the centralization of the fetal circulation associated with fetal hypoxia.


Assuntos
Proteínas de Choque Térmico/genética , Placenta/metabolismo , Complicações na Gravidez/genética , RNA Mensageiro , Estresse Fisiológico/genética , Adulto , Pressão Sanguínea , Feminino , Retardo do Crescimento Fetal/diagnóstico , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/metabolismo , Regulação da Expressão Gênica , Humanos , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/fisiopatologia , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/metabolismo , Complicações na Gravidez/fisiopatologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Ultrassonografia Doppler em Cores
12.
Mediators Inflamm ; 2013: 186041, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24347821

RESUMO

The objective of the study was to identify the profile of circulating C19MC microRNAs (miR-516-5p, miR-517*, miR-518b, miR-520a*, miR-520h, miR-525, and miR-526a) in patients with established preeclampsia (n = 63), fetal growth restriction (n = 27), and gestational hypertension (n = 23). We examined the correlation between plasmatic concentrations and expression levels of microRNAs and the severity of the disease with respect to clinical signs, requirements for the delivery, and Doppler ultrasound parameters. Using absolute and relative quantification approaches, increased extracellular C19MC microRNA levels (miR-516-5p, P = 0.037, P = 0.009; miR-517*, P = 0.033, P = 0.043; miR-520a*, P = 0.001, P = 0.009; miR-525, P = 0.026, P = 0.01; miR-526a, P = 0.03, P = 0.035) were detected in patients with preeclampsia. The association analysis pointed to no relationship between C19MC microRNA plasmatic concentrations and expression profile and identified risk factors for a poorer perinatal outcome. However, the dependence between the levels of plasmatic C19MC microRNAs and the pulsatility index in the middle cerebral artery and the values of cerebroplacental ratio was demonstrated. The study brought the interesting finding that the upregulation of miR-516-5p, miR-517*, miR-520a*, miR-525, and miR-526a is a characteristic phenomenon of established preeclampsia.


Assuntos
Retardo do Crescimento Fetal/genética , Hipertensão Induzida pela Gravidez/genética , MicroRNAs/sangue , Pré-Eclâmpsia/genética , Feminino , Regulação da Expressão Gênica , Humanos , Gravidez/sangue , Índice de Gravidade de Doença , Ultrassonografia Doppler
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