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Background: In the last decade, increasing evidence has suggested that high-grade serous ovarian cancers may have their origin in the fallopian tube rather than the ovary. This emerging theory presents an opportunity to prevent epithelial ovarian cancer by incorporating prophylactic bilateral salpingectomy into all surgical procedures for average-risk women. The aim of this review is to investigate the hypothesis that bilateral salpingectomy (BS) may have a negative impact on ovarian reserve, not only following hysterectomy for benign uterine pathologies but also when performed during cesarean sections as a method of sterilization or as a treatment for hydrosalpinx in Assisted Reproductive Technology interventions. Methods: PubMed, Medline, Google Scholar, and Cochrane were searched for original studies, meta-analyses, and opinion articles published between 2014 and 2024. Results: Out of 114 records from the database search, after the removal of duplicates, 102 articles were considered relevant for the current study. Conclusions: Performing opportunistic salpingectomy seems to have no adverse impact on ovarian function in the short term. However, because there is an existing risk of damaging ovarian blood supply during salpingectomy, there are concerns about potential long-term adverse effects on the ovarian reserve, which need further investigation.
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Pulmonary hypertension (PH) is a progressive and invalidating condition despite available therapy. Addressing complications such as left main coronary artery compression (LMCo) due to the dilated pulmonary artery (PA) may improve symptoms and survival. Nevertheless, clear recommendations are lacking. The aim of this study is to analyze the prevalence, characteristics, predictive factors and impact of LMCo in a heterogenous precapillary PH population in a single referral center. Two hundred sixty-five adults with various etiologies of precapillary PH at catheterization were reviewed. Coronary angiography (CA) was performed for LMCo suspicion. Revascularization was performed in selected cases. Outcomes were assessed at a mean follow-up of 3.9 years. LMCo was suspected in 125 patients and confirmed in 39 (31.2%), of whom 21 (16.8%) had 50%-90% stenoses. Nine revascularizations were performed, with clinical improvement. The only periprocedural complication was a stent migration. LMCo was associated with PH etiology (p 0.003), occuring more frequently in congenital heart disease-associated PH (61.5% of all LMCo cases, 66.6% of LMCo ≥ 50%). Predictors of LMCo ≥50% were PA ≥ 37.5 mm (Sn 81%, Sp 74%) and PA-to-aorta ≥1.24 (Sn 81%, Sp 69%), with increased discrimination when considering RV end-diastolic area. LMCo ≥ 50% without revascularization presented clinical deterioration and worse survival (p 0.019). This analysis of a heterogeneous pre-capillary PH population provides LMCo prevalence estimation, predictive factors (PA size, PA-to-aorta, RV end-diastolic area and PH etiology) and long-term impact. While LMCo impact on survival is inconclusive, untreated LMCo ≥ 50% has worse prognosis. LMCo revascularization may be performed safely and with good outcomes.
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The interest in polymers with high thermal conductivity increased much because of their inherent properties such as low density, low cost, flexibility, and good chemical resistance. However, it is challenging to engineer plastics with good heat transfer characteristics, processability, and required strength. Improving the degree of the chain alignment and forming a continuous thermal conduction network is expected to enhance thermal conductivity. This research aimed to develop polymers with a high thermal conductivity that can be interesting for several applications. Two polymers, namely poly(benzofuran-co-arylacetic acid) and poly(tartronic-co-glycolic acid), with high thermal conductivity containing microscopically ordered structures were prepared by performing enzyme-catalyzed (Novozyme-435) polymerization of the corresponding α-hydroxy acids 4-hydroxymandelic acid and tartronic acid, respectively. A comparison between the polymer's structure and heat transfer obtained by mere thermal polymerization before and enzyme-catalyzed polymerization will now be discussed, revealing a dramatic increase in thermal conductivity in the latter case. The polymer structures were investigated by FTIR spectroscopy, nuclear magnetic resonance (NMR) spectroscopy in liquid- and solid-state (ss-NMR), and powder X-ray diffraction. The thermal conductivity and diffusivity were measured using the transient plane source technique.
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Lipase , Polímeros , Polímeros/química , Condutividade Térmica , Espectroscopia de Ressonância MagnéticaRESUMO
Polydopamine (PDA) formed by oxidative polymerization of dopamine has attracted wide interest because of its unique properties, in particular its strong adhesion to almost all types of surfaces. 3,4-Dihydroxybenzylamine (DHBA) as the lower homolog of PDA also contains a catechol unit and an amino group and thus can be expected to exhibit a similar adhesion and reaction behavior. In fact, autoxidation of DHBA with air in 2-amino-2-hydroxymethyl-propane-1,3-diol (Tris) buffer gives rise to deeply colored oligomer/polymer products (poly(3,4-dihydroxybenzylamine) (PDHBA)) that strongly adhere to several surfaces. Here, the material is characterized by solid-state NMR spectroscopy, Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), electron spin resonance (ESR) spectroscopy, mass spectrometry, and atomic force microscopy (AFM). Reaction pathways were rationalized taking into consideration the analytical results that show similarity to PDA chemistry, but also considering differences, leading to a more complex reaction behavior and thus to new structures not found in PDA.
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Poly(tartaric acid) is a relatively recently described polymer that can be easily synthesized and scaled up from a readily available renewable material (tartaric acid). This article demonstrates its use in a green synthesis of gold nanoparticles, silver nanoparticles, copper particles, and magnetite nanoparticles. In this case poly(tartaric acid) acts both as a reductant and as a coating agent. To our knowledge this is the first green synthesis of several different types of nanoparticles using only one reagent (polytartrate) as both reductant and coating. The resulting particles were analyzed by XRD, TEM/SEM, EDX, FTIR, DLS, zeta-potential, XPS, and UV/VIS spectroscopy. Preliminary studies of the thermal behavior of mixtures of different types of particles with poly(tartaric acid) were also conducted. The obtained particles show different sizes depending on the material, and the coating allows for better dispersibility as well as potential further functionalization, making them potentially useful also for other applications, besides the inclusion in polymer composites.
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Easy and cost-efficient modifications of titanium dioxide nanoparticles that improve their efficiency in the visible light domain represent a continuous and challenging research topic. In addition, the effect of graphene on the overall photocatalytic process is still debated. Consequently, herein, we prepared a series of TiO2 nanoparticle-based composites with different copper oxide mass content (1-3%) and co-doped with graphene of different oxidation degrees. Different characterization techniques were used to analyze the structural and physico-chemical properties of the obtained composites: Scanning Electron Microscopy (SEM)/Transmission Electron Microscopy (TEM)/Energy-dispersive X-ray spectroscopy (EDX) analysis, X-ray powder diffraction (XRD), Fourier-transformed infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The photocatalytic performance was evaluated by the degradation of methylene blue under both UVA and visible light irradiation. The nanocomposites show very good photocatalytic activity independent of the presence of reduced graphene oxide, due to the Cu2O/CuO-TiO2 heterojunctions. This finding has been confirmed by the very efficient visible-light-driven degradation of amoxicillin and ciprofloxacin.
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Grafite , Nanopartículas , Amoxicilina , Catálise , Ciprofloxacina , Cobre , Grafite/química , Luz , Azul de Metileno/química , Óxidos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio/químicaRESUMO
In this paper, the photodynamic effect of a ternary nanocomposite (TiO2-Ag/graphene) on Escherichia coli bacteria and two human cell lines: A375 (melanoma) and HaCaT (keratinocyte) after exposure to different wavelength domains (blue, green or red-Light Emitting Diode, LED) was analyzed. The results obtained through bioassays were correlated with the morphological, structural and spectral data obtained through FT-IR, XPS and UV-Vis spectroscopy, powder X-Ray diffractometry (XRD) and STEM/EDX techniques, leading to conclusions that showed different photodynamic activation mechanisms and effects on bacteria and human cells, depending on the wavelength. The nanocomposite proved a therapeutic potential for blue light-activated antibacterial treatment and revealed a keratinocyte cytotoxic effect under blue and green LEDs. The red light-nanocomposite duo gave a metabolic boost to normal keratinocytes and induced stasis to melanoma cells. The light and nanocomposite combination could be a potential therapy for bacterial keratosis or for skin tumors.
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Escherichia coli/efeitos da radiação , Grafite/química , Luz , Nanocompostos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Queratinócitos/patologia , Queratinócitos/efeitos da radiação , Ceratose/tratamento farmacológico , Ceratose/patologia , Nanocompostos/química , Nanocompostos/uso terapêutico , Prata/química , Titânio/químicaRESUMO
A graphene sample (EGr) was prepared by electrochemical exfoliation of graphite rods in solution containing 0.05 M (NH4)2SO4 + 0.1 M H3BO3 + 0.05 M NaCl. The exfoliation was performed by applying a constant voltage (12 V) between the graphite rods, while the temperature was kept constant (18 °C) with a temperature-controlled cryostat. The structural investigation of the graphene sample, performed by X-ray powder diffraction (XRD), revealed that the sample consists of a mixture of few-layer (69%), multi-layer graphene (14%) and graphene oxide (17%). In addition, XPS analysis proved that the sample was triple-doped with heteroatoms such as nitrogen (1.7 at%), sulfur (2.5 at%), and boron (3 at%). The sample was deposited onto the surface of a clean, glassy carbon electrode (GC) and investigated for the non-enzymatic electrochemical detection of L-tryptophan (TRP). The electrocatalytic properties of the EGr/GC electrode led to a considerable decrease in the oxidation potential from +0.9 V (bare GC) to +0.72 V. In addition, the EGr/GC electrode has higher sensitivity (two times) and a lower detection limit (ten times) in comparison with the bare GC electrode.
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Técnicas Biossensoriais , Técnicas Eletroquímicas , Eletrodos , Grafite/química , Triptofano/análise , OxirreduçãoRESUMO
AIM: To investigate the effects of prenatal exposure to AgNPs obtained by green synthesis with Viburnum opulus L. extract on the testis in male offspring rats. MATERIAL AND METHODS: Two different doses of AgNPs (0.8 and 1.5 mg/kg b.w.) and vehicle (PBS) were administered to Wistar female rats on days 3-14 of gestation. At 6 weeks after birth, the ultrastructural changes in correlation with the amount of silver as well as the parameters of oxidative stress, inflammation and cell death mechanisms in the testis of male offspring were evaluated. RESULTS: AgNPs administered during pregnancy crossed the placental and testicular barriers and induced oxidative stress, DNA damage and autophagy as mechanism of cell toxicity. The markers of inflammation and apoptosis decreased after AgNPs exposure while the NFkB activation increased. TEM examination revealed important ultrastructural changes of Sertoli cells, numerous vacuoles and cytoplasmic changes suggestive of the cell's evolution towards necrosis. CONCLUSION: Phytoreduced silver nanoparticles with polyphenols from Viburnum opulus L. fruit extract, administered during the embryological development of the male gonad, have testicular toxic effects in offspring even at 6 weeks after birth.
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Morte Celular/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Extratos Vegetais/química , Efeitos Tardios da Exposição Pré-Natal , Prata/toxicidade , Viburnum/química , Animais , Citocinas/genética , Citocinas/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação , Masculino , Nanopartículas Metálicas/química , Estresse Oxidativo/efeitos dos fármacos , Gravidez , Ratos , Prata/química , Testículo/citologiaRESUMO
In this study we designed a composite biomaterial based on a high viscosity soft propolis extract (70% propolis) and shell clam, with antiseptic and osteoinductive qualities, that can be used in dentistry, orthopedics and other areas where hard tissue regeneration is needed. We assessed it in interaction with stabilized human cells isolated from dental papilla of wisdom teeth (D1MSCs). We performed detailed characterization of the obtained material by Scanning Electronic Microscopy (SEM), X-Ray Diffraction (XRD), Energy Dispersive X-Ray Spectroscopy (EDX), Fourier Transform Infrared Spectroscopy (FTIR) techniques. SEM investigation revealed the roughness and porosity of the shell, which acted like a scaffold, as it allowed cells to penetrate the pores, proliferate on the surface, spread and grow in the depressions provided by the substrate. in vitro cell viability, proliferation and differentiation assays showed that the newly obtain biomaterial presented low toxicity on D1MSCs and determined the development of numerous osteogenic nodules that were in a higher number even than in the specific induction medium. Our results demonstrated that the shell-propolis based biomaterial promoted and sustained human stem cells attachment, proliferation and differentiation, presenting an important osteoinductive effect essential for mineralized tissue reparation process.
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Materiais Biocompatíveis/química , Mya , Própole , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Diferenciação Celular , Proliferação de Células , Humanos , Osteogênese , Células-Tronco/citologiaRESUMO
This work is focused on self-assembled monolayers (SAMs) fabrication, using two types of Au surfaces, by subsequent attachment of different layers in order to develop a stable platform consisting of covalent multilayer functionalized gold surfaces. The key step in the construction of SAMs is the covalent linkage to the gold surface, via an amino-thiol derivative, of a cyclooctyne unit exhibiting strained triple bonds which react fast (catalysts are not needed) and quantitatively with organic azides and enable the introduction of various chemical functionalized entities on the gold surface. The versatility of the system is demonstrated by the reaction of the cyclooctyne decorated gold surface with an azide functionalized terpyridine followed by step by step complexation with Fe(II) and another terpyridine unit resulting into a multilayer covered gold surface. The Au surfaces were characterized by XPS to determine the chemical composition of the resulting SAMs. SPR was applied for real-time monitoring of the molecular interactions that occurred on the Au surface for each deposited layer. DPN was used to direct pattern the terpyridine-ink on a pre-functionalized AuIDE electrode. The AFM topology resulted from DPN and PEIS demonstrated metal-coordinating ligand of Fe(II)-Terpy.
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Materiais Revestidos Biocompatíveis/química , Ouro/química , Piridinas/química , Química Click/métodos , Ferro/química , Microscopia de Força Atômica , Propriedades de SuperfícieRESUMO
Iron oxide magnetic nanoparticles (IOMNPs) have been successfully synthesized by means of solvothermal reduction method employing polyethylene glycol (PEG200) as a solvent. The as-synthesized IOMNPs are poly-dispersed, highly crystalline, and exhibit a cubic shape. The size of IOMNPs is strongly dependent on the reaction time and the ration between the amount of magnetic precursor and PEG200 used in the synthesis method. At low magnetic precursor/PEG200 ratio, the cubic IOMNPs coexist with polyhedral IOMNPs. The structure and morphology of the IOMNPs were thoroughly investigated by using a wide range of techniques: TEM, XRD, XPS, FTIR, and RAMAN. XPS analysis showed that the IOMNPs comprise a crystalline magnetite core bearing on the outer surface functional groups from PEG200 and acetate. The presence of physisorbed PEG200 on the IOMNP surface is faintly detected through FT-IR spectroscopy. The surface of IOMNPs undergoes oxidation into maghemite as proven by RAMAN spectroscopy and the occurrence of satellite peaks in the Fe2p XP spectra. The magnetic studies performed on powder show that the blocking temperature (TB) of IOMNPs is around 300 K displaying a coercive field in between 160 and 170 Oe. Below the TB, the field-cooled (FC) curves turn concave and describe a plateau indicating that strong magnetic dipole-dipole interactions are manifested in between IOMNPs. The specific absorption rate (SAR) values increase with decreasing nanoparticle concentrations for the IOMNPs dispersed in water. The SAR dependence on the applied magnetic field, studied up to magnetic field amplitude of 60 kA/m, presents a sigmoid shape with saturation values up to 1700 W/g. By dispersing the IOMNPs in PEG600 (liquid) and PEG1000 (solid), it was found that the SAR values decrease by 50 or 75 %, indicating that the Brownian friction within the solvent was the main contributor to the heating power of IOMNPs.
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One of the most fundamental aspects of the heterogeneous catalysis field is the manipulation of the catalysts' activity. In photocatalysis this is carried out by maximizing the right crystal plane of a semiconductor oxide. Until now, most of the papers have achieved this by a combination of different oxides, with noble metals and sometimes with carbon nanomaterials. In this work MWCNTs (multiwalled carbon nanotubes) were applied as "crystallization promoters" in a very simple, safe, one-step hydrothermal method. By this method TiO2 nano/micro crystals with exposed {001} facets were obtained in the first step. The next episode in the crystal manipulation "saga" was the modification of the (001) crystallographic plane's structure by creating ordered/own faceted "crystallographic holes". These elements are capable of further enhancing the obtained activity of titania microcrystals to a higher extent, as shown by the UV driven photocatalytic phenol degradation experiments. The appearance of the holes was "provoked" by simple calcination and their presence and influence were demonstrated by XPS and HRTEM.
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The study is focused on synthesis, investigation of the structural and morphological changes induced by MoO3 addition, and thermal treatment, as well as in vitro characterization of a new sol-gel derived SiO2-CaO-P2O5 bioactive materials. The obtained systems are composite materials consisting of nanocrystalline apatite, bioactive glass and CaMoO4 nanoparticles, which are of interest for both regenerative medicine and specific medical applications of the releasable molybdenum ions. The changes induced by the thermal treatments and MoO3 addition with respect to the structure and morphology were completed using differential thermal analysis\thermogravimetric analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, electron paramagnetic resonance, and Brunauer-Emmett-Teller. The biological performance of these materials was evaluated in vitro by performing bioactivity and biocompatibility tests. The bioactive properties in terms of hydroxyapatite layer formation on the biomaterial surface after simulated body fluid immersion were studied by XRD and SEM. To establish their biocompatibility, the biomaterials surface was functionalized with protein and the resulted sample was investigated using SEM, FTIR, and XPS. The obtained results suggest that the addition of molybdenum oxide in proper concentration improves the biocompatibility in terms of enhancement of protein adherence on Si-Ca-P surface due to CaMoO4 crystalline phase development and does not inhibit bioactivity.
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Materiais Biocompatíveis/química , Compostos de Cálcio/química , Molibdênio/química , Óxidos/química , Compostos de Fósforo/química , Dióxido de Silício/química , Animais , Líquidos Corporais/química , Bovinos , Nanopartículas/química , Nanopartículas/ultraestrutura , Transição de Fase , Espectroscopia Fotoeletrônica , Soroalbumina Bovina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios XRESUMO
One weight percent of differently sized Au nanoparticles were deposited on two commercially available TiO2 photocatalysts: Aeroxide P25 and Kronos Vlp7000. The primary objective was to investigate the influence of the noble metal particle size and the deposition method on the photocatalytic activity. The developed synthesis method involves a simple approach for the preparation of finely-tuned Au particles through variation of the concentration of the stabilizing agent. Au was deposited on the TiO2 surface by photo- or chemical reduction, using trisodium citrate as a size-tailoring agent. The Au-TiO2 composites were synthetized by in situ reduction or by mixing the titania suspension with a previously prepared gold sol. The H2 production activities of the samples were studied in aqueous TiO2 suspensions irradiated with near-UV light in the absence of dissolved O2, with oxalic acid or methanol as the sacrificial agent. The H2 evolution rates proved to be strongly dependent on Au particle size: the highest H2 production rate was achieved when the Au particles measured ~6 nm.
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Bioactive glasses doped with silver are aimed to minimize the risk of microbial contamination; therefore, the influence of silver on the bioactive properties is intensely investigated. However, information related to the role played by silver, when added to the bioactive glass composition, on biocompatibility properties is scarce. This aspect is essential as long as the silver content can influence blood protein adsorption onto the surface of the glass, thus affecting the material's biocompatibility. Therefore, from the perspective of the biocompatibility standpoint, the finding of an optimal silver content in a bioactive glass is an extremely important issue. In this study, silver-doped bioactive glasses were prepared by a melt-derived technique, which eliminates the pores' influence in the protein adsorption process. The obtained glasses were characterized by X-ray diffraction, UV-vis, X-ray photoelectron (XPS) and Fourier transform infrared (FT-IR) spectroscopy; afterwards, they were investigated in terms of protein adsorption. Both UV-vis and XPS spectroscopy revealed the presence of Ag+ ions in all silver containing samples. By increasing the silver content, metallic Ag0 appears, the highest amount being observed for the sample with 1 mol% AgO2. Electron paramagnetic resonance measurements evidenced that the amount of spin-labeled serum albumin attached to the surface increases with the silver content. The results obtained by analyzing the information derived from atomic force microscopy and FT-IR measurements indicate that the occurrence of metallic Ag0 in the samples' structure influences the secondary structure of the adsorbed protein. Based on the results derived from the protein response upon interaction with the investigated glass calcium-phosphate based system, the optimal silver oxide concentration was determined for which the secondary structure of the adsorbed protein is similar with that of the free one. This concentration was found to be 0.5 mol%.