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1.
ACS Sustain Chem Eng ; 12(7): 2771-2782, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38389903

RESUMO

Potassium exchanged Sn-ß and Sn-USY zeolites have been tested for the transformation of various aldoses (hexoses and pentoses), exhibiting outstanding catalytic activity and selectivity toward methyl lactate. Insights into the transformation pathways using reaction intermediates-dihydroxyacetone and glycolaldehyde-as substrates revealed a very high catalytic proficiency of both zeolites in aldol and retro-aldol reactions, showcasing their ability to convert small sugars into large sugars, and vice versa. This feature makes the studied Sn-zeolites outstanding catalysts for the transformation of a wide variety of sugars into a limited range of commercially valuable alkyl lactates and derivatives. [K]Sn-ß proved to be superior to [K]Sn-USY in terms of shape selectivity, exerting tight control on the distribution of produced α-hydroxy methyl esters. This shape selectivity was evident in the transformation of several complex sugar mixtures emulating different hemicelluloses-sugar cane bagasse, Scots pine, and white birch-that, despite showing very different sugar compositions, were almost exclusively converted into methyl lactate and methyl vinyl glycolate in very similar proportions. Moreover, the conversion of a real hemicellulose hydrolysate obtained from Scots pine through a simple GVL-based organosolv process confirmed the high activity and selectivity of [K]Sn-ß in the studied transformation, opening new pathways for the chemical valorization of this plentiful, but underutilized, sugar feedstock.

2.
Cir Cir ; 91(4): 571-575, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37677950

RESUMO

Aortoenteric fistula is an uncommun life-threatening condition which remains associated with significant morbidity and mortality. It can be primary (aneurysm, neoplasms, radiation therapy, infection) or secondary to vascular prosthesis. Early diagnosis and aggressive surgical treatment are very important to achieve optimal outcomes in these patients. The aim of this article is to highlight the importance of early diagnosis and multidisciplinary approach of aortoenteric fistula through the presentation of a clinical case.


La fístula aortoentérica es una patología poco frecuente, pero de riesgo vital, asociada a alta morbimortalidad. Puede ser primaria (aneurisma, neoplasia, radioterapia, infección) o secundaria a prótesis vascular. El diagnóstico precoz y el tratamiento quirúrgico agresivo son los pilares fundamentales para lograr buenos resultados en estos pacientes. El objetivo de este trabajo es destacar la importancia del diagnóstico precoz de la fístula aortoentérica y su manejo multidisciplinar, mediante la presentación de un caso clínico.


Assuntos
Doenças da Aorta , Fístula , Humanos , Doenças da Aorta/etiologia , Doenças da Aorta/cirurgia , Prótese Vascular
5.
Clin Oral Implants Res ; 34(2): 137-147, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36541106

RESUMO

BACKGROUND: The aim of this randomized clinical trial was to evaluate the effect of diode laser photobiomodulation (PBM) on post-surgical healing, inflammation and implant stability. METHODS: Forty dental implants were inserted into 13 patients. The implants were randomly divided into two groups. The test group (PBM+) underwent two sessions of PBM (combined diode laser of 630 and 808 nm), the first of which after surgery, and the second, 7 days after the surgical procedure. The control group (PBM-) received simulated laser treatment. The implant stability quotient (ISQ) was determined immediately after the surgical procedure, and 7 days, 4 and 8 weeks later. Post-surgical inflammation was assessed following the criteria described by Bloemen and Cols. Healing was calculated using the healing index (HI). RESULTS: No differences were found in terms of the mean values of implant stability between the test and control groups over time. Only two of the implants (18.2%) from the PBM- group were classified with the maximum healing index (HI = 5), whereas in the PBM+ group, nine implants (45%) were classified with the aforementioned index (P < 0.0001). Using the logistic regression, it was determined that the non-application of the laser in the PBM- group caused an OR of 4.333 times of presenting inflammation (IC95% 1.150-16.323; P = 0.030). CONCLUSIONS: The application of 808 nm infra-red laser for bone tissue, and 630 nm for mucosal tissue in two sessions is considered to be an effective way of reducing inflammation and improving early healing. More studies are needed to confirm these results.


Assuntos
Implantes Dentários , Terapia com Luz de Baixa Intensidade , Humanos , Método Duplo-Cego , Implantação Dentária Endóssea/métodos , Lasers Semicondutores , Osso e Ossos
6.
ACS Appl Mater Interfaces ; 14(45): 50739-50750, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36321841

RESUMO

The design of an active, effective, and economically viable catalyst for CO2 conversion into value-added products is crucial in the fight against global warming and energy demand. We have developed very efficient catalysts for reverse water-gas shift (rWGS) reaction. Specific conditions of the synthesis by combustion allow the obtention of macroporous materials based on nanosized Ni particles supported on a mixed oxide of high purity and crystallinity. Here, we show that Ni/La-doped CeO2 catalysts─with the "right" Ni and La proportions─have an unprecedented catalytic performance per unit mass of catalyst for the rWGS reaction as the first step toward CO2 valorization. Correlations between physicochemical properties and catalytic activity, obtained using a combination of different techniques such as X-ray and neutron powder diffraction, Raman spectroscopy, in situ near ambient pressure X-ray photoelectron spectroscopy, electron microscopy, and catalytic testing, point out to optimum values for the Ni loading and the La proportion. Density functional theory calculations of elementary steps of the reaction on model Ni/ceria catalysts aid toward the microscopic understanding of the nature of the active sites. This finding offers a fundamental basis for developing economical catalysts that can be effectively used for CO2 reduction with hydrogen. A catalyst based on Ni0.07/(Ce0.9La0.1Ox)0.93 shows a CO production of 58 × 10-5 molCO·gcat-1·s-1 (700 °C, H2/CO2 = 2; selectivity to CO > 99.5), being stable for 100 h under continuous reaction.

7.
ACS Sustain Chem Eng ; 10(27): 8885-8896, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35846797

RESUMO

Sn-USY materials have been prepared through an optimized post-synthetic catalytic metalation procedure. These zeolites displayed, upon ion exchange with alkaline metals, an outstanding activity in the direct transformation of glucose into methyl lactate, yielding more than 70% of the starting glucose as the target product, and an overall combined retro-aldol condensation product yield above 95% in a short reaction time (<4 h). This outstanding catalytic performance is ascribed to the neutralization of Brønsted acid sites, the consequent depression of side reactions, and a higher population of tin open sites in the ion-exchanged Sn-USY zeolites. Reusability tests evidenced some loss of catalytic activity, partially caused by the closing of tin sites, although the use of small amounts of water in the reaction media demonstrated that this deactivation mechanism can be, at least, partially alleviated.

8.
Clin Oral Implants Res ; 33(10): 1038-1048, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35869615

RESUMO

OBJECTIVES: The objective of this study was to analyze the impact of the abutment width on early marginal bone loss (MBL). MATERIAL AND METHODS: A balanced, randomized, double-blind clinical trial with two parallel experimental arms was conducted without a control group. The arms were "cylindrical" abutment and "concave" abutment. Eighty hexagonal internal connection implants, each with a diameter of 4 × 10 mm, were placed in healed mature bone. The main variable was the peri-implant tissue stability, which was measured as MBL at 8 weeks and 6 months. RESULTS: The final sample consisted of 77 implants that were placed in 25 patients. 38 (49.4%) were placed using the cylindrical abutment, and the other 39 (50.6%) were placed using the concave abutment. The early global MBL of -0.6 ± 0.7 mm in the cylindrical abutment group was significantly higher than it was in the concave abutment group, in which the early global MBL was -0.4 ± 0.6 mm (p = .030). The estimated effect size (ES) was negative for the cylindrical abutment (ES = -1.3730, CI -2.5919 to -0.1327; t-value = -2.4893; p = .0139), therefore implying a loss of mean bone level, and it was positive for the concave abutment (ES = 2.8231; CI: 1.4379 to 4.2083; t-value = 4.0957; p = .0002), therefore implying an increase in the average bone level. CONCLUSIONS: The concave abutments presented significantly less early MBL at 6 months post-loading than classical cylindrical abutments did.


Assuntos
Perda do Osso Alveolar , Implantes Dentários para Um Único Dente , Implantes Dentários , Dente Suporte , Projeto do Implante Dentário-Pivô , Implantação Dentária Endóssea , Humanos
9.
Int J Oral Implantol (Berl) ; 15(1): 71-86, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35266670

RESUMO

PURPOSE: To evaluate marginal bone loss 6 and 12 months after prosthetic loading of implants with Dynamic Bone Management (Straumann, Basel, Switzerland) through the implementation of different drilling protocols. MATERIALS AND METHODS: A balanced, randomised, single-blind clinical trial was conducted with four parallel experimental arms: immediate loading and under-drilling, immediate loading and complete drilling, early loading and under-drilling, and early loading and complete drilling. Forty-four implants with a Dynamic Bone Management design and with a diameter of 3.75 mm and a length of 10.00 mm were placed in healed mature bone (more than 6 months post-extraction). RESULTS: The mean primary stability achieved was 60.6 ± 12.2 implant stability quotient, with a range from 21 to 75, and no differences were observed when considering the drilling protocol used, bone type or location. Early loading resulted in a loss of 0.728 mm (standard error 0.212; 95% confidence interval 1.134 to -0.325; t value -3.440), whereas immediate loading did not result in any bone loss. When the interaction between the loading and drilling protocols was studied, performing the complete drilling protocol in conjunction with early implant loading was found to result in lower marginal bone loss, with a marginal bone gain effect of 0.814 mm (standard error 0.283; 95% confidence interval -0.274 to 1.353; t value 2.880). CONCLUSIONS: Use of the complete drilling protocol in conjunction with early implant loading resulted in the lowest marginal bone loss at 12 months.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Perda do Osso Alveolar/etiologia , Implantação Dentária Endóssea/métodos , Humanos , Mandíbula/cirurgia , Método Simples-Cego
10.
Nanomaterials (Basel) ; 12(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35269267

RESUMO

Nanostructured silver (Ag) and gold (Au) are widely known to be potent biocidal and cytotoxic agents as well as biocompatible nanomaterials. It has been recently reported that combining both metals in a specific chemical composition causes a significant enhancement in their antibacterial activity against antibiotic-resistant bacterial strains, as well as in their anticancer effects, while preserving cytocompatibility properties. In this work, Ag/Au bimetallic nanoparticles over a complete atomic chemical composition range were prepared at 10 at% through a green, highly reproducible, and simple approach using starch as a unique reducing and capping agent. The noble metal nanosystems were thoroughly characterized by different analytical techniques, including UV-visible and FT-IR spectroscopies, XRD, TEM/EDS, XPS and ICP-MS. Moreover, absorption spectra simulations for representative colloidal Ag/Au-NP samples were conducted using FDTD modelling. The antibacterial properties of the bimetallic nanoparticles were determined against multidrug-resistant Escherichia coli and methicillin-resistant Staphylococcus aureus, showing a clear dose-dependent inhibition even at the lowest concentration tested (5 µg/mL). Cytocompatibility assays showed a medium range of toxicity at low and intermediate concentrations (5 and 10 µg/mL), while triggering an anticancer behavior, even at the lowest concentration tested, in a process involving reactive oxygen species production per the nanoparticle Au:Ag ratio. In this manner, this study provides promising evidence that the presently fabricated Ag/Au-NPs should be further studied for a wide range of antibacterial and anticancer applications.

11.
Med. oral patol. oral cir. bucal (Internet) ; 27(1): e59-e67, jan. 2022. tab, graf
Artigo em Inglês | IBECS | ID: ibc-204329

RESUMO

Background: Alcohol use disorder (AUD) is directly linked to high-risk consumption. Healthcare students have a crucial role to play in its prevention and management. The aim of this study is to analyse alcohol consumption, as well as to consider the knowledge and attitudes regarding morbidity, and the stage of change when providing assistance to quit AUD. Material and Methods: A cross-sectional study was conducted among Dentistry and Medical students using specific and validated questionnaires in an anonymous and voluntary way. Initially, 925 students were invited to participate, of them 500 were reached. Results: Among them 85.9% suffered from AUD of whom 75% were women (p<0.001), and it was considered that the female gender constituted an independent risk factor (OR=2.63, CI 95% 1.55-4.45, p<0.001). The majority of the participants did not achieve the pass mark, nonetheless, the results showed improved levels of knowledge among participants in the latter years of their studies (p<0.001). Dental students demonstrated greater shortcomings in terms of their knowledge of general pathology, whereas the medical students’ knowledge of oral pathologies proved worse (p<0.001). Most of students believed that identifying cases of AUD-affected patients falls within their competence, nonetheless, they believed that they do not have the necessary competencies. Among participants 58.2% were in a stage of change regarding AUD attitudes. Conclusions: The majority of respondents presented AUD. In general, the participants’ knowledge about alcohol was low. Reviewing the syllabuses and evaluating the implementation of gender-differentiated training programmes in both degrees would be considered necessary.(AU)


Assuntos
Humanos , Adulto , Consumo de Bebidas Alcoólicas , Atitude do Pessoal de Saúde , Aconselhamento , Mulheres , Letramento em Saúde , Morbidade , Estudos Transversais , Humanos , Estudantes de Medicina
12.
Ind Eng Chem Res ; 60(44): 15999-16010, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34949902

RESUMO

This work reports initial results on the effect of low concentrations (ppm level) of a stabilizing agent (2,6-di-tert-butyl-4-methylphenol, BHT) present in an off-the-shelf solvent on the catalyst performance for the hydrogenolysis of γ-butyrolactone over Cu-ZnO-based catalysts. Tetrahydrofuran (THF) was employed as an alternative solvent in the hydrogenolysis of γ-butyrolactone. It was found that the Cu-ZnO catalyst performance using a reference solvent (1,4-dioxane) was good, meaning that the equilibrium conversion was achieved in 240 min, while a zero conversion was found when employing tetrahydrofuran. The deactivation was studied in more detail, arriving at the preliminary conclusion that one phenomenon seems to play a role: the poisoning effect of a solvent additive present at the ppm level (BHT) that appears to inhibit the reaction completely over a Cu-ZnO catalyst. The BHT effect was also visible over a commercial Cu-ZnO-MgO-Al2O3 catalyst but less severe than that over the Cu-ZnO catalyst. Hence, the commercial catalyst is more tolerant to the solvent additive, probably due to the higher surface area. The study illustrates the importance of solvent choice and purification for applications such as three-phase-catalyzed reactions to achieve optimal performance.

13.
Medicina (Kaunas) ; 57(10)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34684129

RESUMO

Background and objectives: The purpose of this study was to analyse the diagnostic and prognostic efficiency of the sentinel lymph node biopsy technique (SLNB). Materials and Methods: This is a prospective observational study performed by the Hospital Complex in Santiago de Compostela (CHUS) in Spain, between February 2013 and June 2020. The study included 60 patients, who had been diagnosed with OSCC in stage T1/T2N0M0. Results: 10 patients (16.7%) presented with SN+ (sentinel node positive). The majority (80%) only presented subcapsular affection, however one case also presented with extracapsular affection. Using the Kaplan-Meier curves, we determined that the average survival estimation for SN- patients was 74.0 months (CI95% 67.6-80.5) and it was 45.4 months (CI95% 10.9-24.0) for SN+ patients (p = 0.002). SN+ patients presented an OR = 11.000 (CI95% 2.393-50.589, p = 0.002) for cancer-related mortality. In terms of the diagnostic performance of the SN (sentinel node) test, a 55% sensitivity, a 100% specificity, 100% PPV and a 84% NPV were obtained. The analysis using ROC (receiver operating characteristic) curves revealed an AUC = 0.671 (CI95% 0.492-0.850, p = 0.046). Conclusions: SLNB seems to be an adequate technique for the detection of hidden metastases.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Humanos , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Estadiamento de Neoplasias , Prognóstico , Biópsia de Linfonodo Sentinela , Carcinoma de Células Escamosas de Cabeça e Pescoço
16.
Odontology ; 109(3): 574-584, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33428015

RESUMO

The objective of this paper is to clarify the rate of abdominal obesity (AO), waist-to-height ratio (WHtR), metabolic syndrome (MetS) and determine the relationship with the masticatory capacity (MC) in terms of total functional tooth units (t-FTU) in a representative sample of older Spanish adults. This cross-sectional study included 544 adult subjects aged 50 or over, who were prospectively selected and who had participated in a survey conducted in a primary dental care service in a Public Oral Health Service in Spain. Anthropometric, clinical variables and t-FTUs were obtained through a calibrated and well-established protocol. Univariate and multivariate binary and multinomial logistic regression analyses were developed. With regards to the t-FTU or MC, it was poor in 60.3%, good in 17.6%, and complete in 22.1% of the sample. The univariate odss ratio (OR) for MetS and AO increased as the MC decreased and as the age group increased. With regards to gender, women presented with an OR of 5.56 (CI 95% 3.70-8.38). With regards to the WHtR-a3 (WHtR grouped into three categories), the univariate ORs were all significant for morbid obesity compared to the healthy group, with a risk of 6.86 (CI 95% 3.23-14.58) for patients with poor MC compared to those with complete MC. Masticatory hypofunctionality could be associated with the presence of MetS. Clinical relevance: The number of t-FTUs is directly related to AO.


Assuntos
Síndrome Metabólica , Obesidade Abdominal , Adulto , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Síndrome Metabólica/epidemiologia , Fatores de Risco , Espanha/epidemiologia , Razão Cintura-Estatura
17.
Vaccine ; 39(3): 554-563, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33334613

RESUMO

TRIAL DESIGN: An interventional, phase 4, single group assignment, without masking (open label), preventive clinical trial was carried out in health workers with biological risk in their tasks, who have been filed as non-responders to conventional vaccination against Hepatitis B. METHODS: 67 health workers with biological risk in their tasks, who have been filed as non-responders to conventional vaccination against Hepatitis B, were enrolled in the Clinical Trial. All participants were from 18 years up to 64 years old. INCLUSION CRITERIA: NHS workers -including university students doing their internships in health centres dependent on the National Health System (inclusion of students is regulated and limited by specific instructions on labour prevention in each autonomous community)- classified as non-responders. The criteria defining them as non-responders to the conventional hepatitis B vaccine is anti HBsAb titers < 10 mUI/ml following the application of six doses of conventional vaccine at 20 µg doses (two complete guidelines). The objective of this study was to provide Health workers-staff with an additional protection tool against hepatitis B infection, and to evaluate the efficacy of the adjuvanted vaccine in healthy non-responders to conventional hepatitis B vaccine. The primary outcome was the measurement of antibody antiHBs before the first Fendrix® dose and a month after the administration of each dose. Other outcome was collection of adverse effects during administration and all those that could be related to the vaccine and that occur within 30 days after each dose. In this study, only one group was assigned. There was no randomization or masking. RESULTS: The participants were recruited between April 13, 2018 and October 31, 2019. 67 participants were enrolled in the Clinical Trial and included the analyses. The primary immunisation consists of 4 separate 0.5 ml doses of Fendrix®, administered at the following schedule: 1 month, 2 months and 6 months from the date of the first dose. Once the positivity was reached in any of the doses, the participant finished the study and was not given the following doses. 68.66% (46 out 67) had a positive response to first dose of Fendrix®. 57.14% (12 out 21) had a positive response to second dose of Fendrix®. 22.22% (2 out 9) had a positive response to third dose of Fendrix and 42.96% (3 out 7) had a positive response to last dose of Fendrix®. Overall, 94.02% (64 out 67) of participants had a positive response to Fendrix®. No serious adverse event occurred. CONCLUSIONS: The use of Fendrix®, is a viable vaccine alternative for NHS workers classified as "non-responders". Revaccination of healthy non-responders with Fendrix®, resulted in very high proportions of responders without adverse events. TRIAL REGISTRATION: The trial was registered in the Spanish National Trial Register (REEC), ClinicalTrials.gov and inclusion has been stopped (identifier NCT03410953; EudraCT-number 2016-004991-23). FUNDING: GRS 1360/A/16: Call for aid for the financing of research projects in biomedicine, health management and socio-health care to be developed in the centres of the Regional Health Management of Autonomous Community of Castile-Leon. In addition, this work has been supported by the Spanish Platform for Clinical Research and Clinical Trials, SCReN (Spanish Clinical Research Network), funded by the Subdirectorate General for Research Evaluation and Promotion of the Carlos III Health Institute (ISCIII), through the project PT13/0002/0039 and project PT17/0017/0023 integrated in the State Plan for R&D&I 2013-2016 and co-financed by and the European Regional Development Fund (ERDF).


Assuntos
COVID-19 , Hepatite B , Atenção à Saúde , Hepatite B/prevenção & controle , Vacinas contra Hepatite B , Humanos , SARS-CoV-2 , Vacinação
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