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1.
Mol Psychiatry ; 27(5): 2457-2469, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35256745

RESUMEN

Mutations linked to neurodevelopmental disorders, such as intellectual disability (ID), are frequently found in genes that encode for proteins of the excitatory synapse. Transmembrane AMPA receptor regulatory proteins (TARPs) are AMPA receptor auxiliary proteins that regulate crucial aspects of receptor function. Here, we investigate a mutant form of the TARP family member stargazin, described in an ID patient. Molecular dynamics analyses predicted that the ID-associated stargazin variant, V143L, weakens the overall interface of the AMPAR:stargazin complex and impairs the stability of the complex. Knock-in mice harboring the V143L stargazin mutation manifest cognitive and social deficits and hippocampal synaptic transmission defects, resembling phenotypes displayed by ID patients. In the hippocampus of stargazin V143L mice, CA1 neurons show impaired spine maturation, abnormal synaptic transmission and long-term potentiation specifically in basal dendrites, and synaptic ultrastructural alterations. These data suggest a causal role for mutated stargazin in the pathogenesis of ID and unveil a new role for stargazin in the development and function of hippocampal synapses.


Asunto(s)
Canales de Calcio , Discapacidad Intelectual , Receptores AMPA , Animales , Canales de Calcio/genética , Canales de Calcio/metabolismo , Hipocampo/metabolismo , Humanos , Discapacidad Intelectual/genética , Discapacidad Intelectual/metabolismo , Ratones , Mutación/genética , Receptores AMPA/genética , Receptores AMPA/metabolismo , Sinapsis/metabolismo , Transmisión Sináptica/genética
2.
Nanotechnology ; 34(43)2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37473751

RESUMEN

Improving the thermal resilience of magnetic tunnel junctions (MTJs) broadens their applicability as sensing devices and is necessary to ensure their operation under harsh environments. In this work, we are address the impact of temperature on the degradation of the magnetic reference in field sensor stacks based on MgO-MTJs. Our study starts by simple MnIr/CoFe bilayers to gather enough insights into the role of critical morphological and magnetic parameters and their impact in the temperature dependent behavior. The exchange bias coupling field (Hex), coercive field (Hc), and blocking temperature (Tb) distribution are tuned, combining tailored growth conditions of the antiferromagnet and different buffer layer materials and stackings. This is achieved by a unique combination of ion beam deposition and magnetron sputtering, without vaccum break. Then, the work then extends beyond bilayers into more complex state-of-the-art MgO MTJ stacks as those employed in commercial sensing applications. We systematically address their characteristic fields, such as the width of the antiferromagnetic coupling plateau ΔH, and study their dependence on temperature. Although, [Ta/CuN] buffers showed higher key performance indications (e.g.Hex) at room temperature in both bilayers and MTJs, [Ta/Ru] buffers showed an overall wider ΔHup to 200 °C, more suitable to push high temperature operations. This result highlights the importance of properly design a suitable buffer layer system and addressing the complete MTJ behavior as function of temperature, to deliver the best stacking design with highest resilience to high temperature environments.

3.
Med Oral Patol Oral Cir Bucal ; 28(5): e433-e441, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37330965

RESUMEN

BACKGROUND: The aim of the present study was to evaluate postoperative effects of platelet-rich fibrin (PRF) in wound and bone healing, pain, swelling and periodontal complications outcomes after impacted third molars extraction. MATERIAL AND METHODS: A prospective, randomized, split-mouth, double-blind clinical trial was conducted. PRF was placed within sockets following tooth removal and before suturing mucoperiosteal flap while no treatment was performed on control group's sockets. Patients were evaluated considering bone volume which was obtained in the 90-day postoperative period. Other variables included trabecular thickness, trabecular distance and grey values, pain, swelling, and wound healing. A Wilcoxon test and a t-Student test were used at a 5% significance level and a Friedman test was used to multiple comparisons. RESULTS: Forty-four surgeries were performed in the present study. The patients' mean age was 22.41 (± 2.75 years) and 72.73% were women. PRF was associated to increased trabecular thickness and bone volume means (p < 0.001). The experimental group had significantly lower pain scores at 4h, 6h, 8h, 16h, 24h, and 72h (p ˂ 0.05). Mean swelling was lower on the experimental group (p < 0.001). The PRF group showed significant higher wound healing (p ˂ 0.001). CONCLUSIONS: Alveolar filling with PRF improves wound and bone healing after extractions while also decreasing pain and swelling in the postoperative period.


Asunto(s)
Fibrina Rica en Plaquetas , Diente Impactado , Humanos , Femenino , Adulto Joven , Adulto , Masculino , Tercer Molar/cirugía , Estudios Prospectivos , Extracción Dental/efectos adversos , Diente Impactado/cirugía , Dolor/etiología
4.
Trop Anim Health Prod ; 53(4): 427, 2021 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-34341838

RESUMEN

The present study assessed the influence of the type of the tropical pastures on lamb body weight (BW) gain and meat quality. Fifty-four lambs were allocated to three grazing pastures: (1) AG - Aruana grass (Panicum maximum cv. IZ-5); (2) PP - pigeon pea legume (Cajanus cajan cv. Anão); and (3) CS - contiguous swards, half of the paddock with AG and half with PP. After 92 days of grazing, the lambs were slaughtered. Carcasses were evaluated and the longissimus muscle was collected to determine color, lipid profile, tocopherol concentrations, and lipid oxidation. Although the pastures present differences in the characteristics of nutritional quality, the animals did not show difference in BW gain. The results show that all forage presented similar concentration of alpha-tocopherol (137 ± 14.37 mg kg-1 of fresh matter), whereas total and condensed tannin contents were greater in PP, intermediate in CS, and the lowest in AG treatment (P = 0.0001). Meat α-tocopherol content was similar among treatments (P = 0.1392), with an average concentration close to the optimal level to reduce the meat oxidation. Meat from AG treatment had 45 and 25% lower n-6/n-3 ratio than meat from PP and CS treatments, respectively. The legume increases the unsaturated fatty acids and the grass can reduce the n6/n3 ratio. The level of condensed tannin concentration did show to have important effect on meat characteristics. Both tropical pastures studied can provide a high amount of alpha-tocopherol, generating a great potential to increase the concentration of this antioxidant in lamb's meat.


Asunto(s)
Fabaceae , Carne Roja , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Carne/análisis , Poaceae , Ovinos
5.
Mol Biol Rep ; 47(1): 337-351, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31650383

RESUMEN

An imbalance in the redox state, increased levels of lipid precursors and overactivation of de novo lipogenesis determine the development of fibrosis during nonalcoholic steatohepatitis (NASH). We evaluated the modulation of NADPH-producing enzymes associated with the antifibrotic, antioxidant and antilipemic effects of nicotinamide (NAM) in a model of NASH induced by excess fructose consumption. Male rats were provided drinking water containing 40% fructose for 16 weeks. During the last 12 weeks of fructose administration, water containing NAM was provided to some of the rats for 5 h/day. The biochemical profiles and the ghrelin, leptin, lipoperoxidation and TNF-α levels in serum and the glucose-6-phosphate dehydrogenase (G6PD), malic enzyme (ME) and NADP+-dependent isocitric dehydrogenase (IDP) levels, the reduced/oxidized glutathione (GSH/GSSG) and reduced/oxidized nicotinamide adenine dinucleotide (phosphate) (NAD(P)H/NAD(P)+) ratios, and the levels of various lipogenic and fibrotic markers in the liver were evaluated. The results showed that hepatic fibrosis induced by fructose consumption was associated with weight gain, hunger-satiety system dysregulation, hyperinsulinemia, dyslipidemia, lipoperoxidation and inflammation. Moreover, increased levels of hepatic G6PD and ME activity and expression, the NAD(P)H/NAD(P)+ ratios, and GSSG concentration and increased expression of lipogenic and fibrotic markers were detected, and these alterations were attenuated by NAM administration. Specifically, NAM diminished the activity and expression of G6PD and ME, and this effect was associated with a decrease in the NADPH/NADP+ ratios, increased GSH levels and decreased lipoperoxidation and inflammation, ameliorating fibrosis and NASH development. NAM reduces liver steatosis and fibrosis by regulating redox homeostasis through a G6PD- and ME-dependent mechanism.


Asunto(s)
Hígado Graso/metabolismo , Hígado Graso/prevención & control , Niacinamida/farmacología , Animales , Antioxidantes/metabolismo , Fructosa/efectos adversos , Fructosa/metabolismo , Glucosa/metabolismo , Glutatión/metabolismo , Homeostasis , Metabolismo de los Lípidos/fisiología , Lípidos/biosíntesis , Lipogénesis/fisiología , Hígado/metabolismo , Hígado/patología , Cirrosis Hepática/patología , Masculino , NAD/metabolismo , NADP/metabolismo , Niacinamida/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Oxidación-Reducción/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
6.
Int Endod J ; 51 Suppl 1: e55-e64, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28654211

RESUMEN

AIM: To investigate the effects of ultrasonic activation file type, lateral canal location and irrigant on the removal of a biofilm-mimicking hydrogel from a fabricated lateral canal. Additionally, the amount of cavitation and streaming was quantified for these parameters. METHODOLOGY: An intracanal sonochemical dosimetry method was used to quantify the cavitation generated by an IrriSafe 25 mm length, size 25 file inside a root canal model filled with filtered degassed/saturated water or three different concentrations of NaOCl. Removal of a hydrogel, demonstrated previously to be an appropriate biofilm mimic, was recorded to measure the lateral canal cleaning rate from two different instruments (IrriSafe 25 mm length, size 25 and K 21 mm length, size 15) activated with a P5 Suprasson (Satelec) at power P8.5 in degassed/saturated water or NaOCl. Removal rates were compared for significant differences using nonparametric Kruskal-Wallis and/or Mann-Whitney U-tests. Streaming was measured using high-speed particle imaging velocimetry at 250 kfps, analysing both the oscillatory and steady flow inside the lateral canals. RESULTS: There was no significant difference in amount of cavitation between tap water and oversaturated water (P = 0.538), although more cavitation was observed than in degassed water. The highest cavitation signal was generated with NaOCl solutions (1.0%, 4.5%, 9.0%) (P < 0.007) and increased with concentration (P < 0.014). The IrriSafe file outperformed significantly the K-file in removing hydrogel (P < 0.05). Up to 64% of the total hydrogel volume was removed after 20 s. The IrriSafe file typically outperformed the K-file in generating streaming. The oscillatory velocities were higher inside the lateral canal 3 mm compared to 6 mm from WL and were higher for NaOCl than for saturated water, which in turn was higher than for degassed water. CONCLUSIONS: Measurements of cavitation and acoustic streaming have provided insight into their contribution to cleaning. Significant differences in cleaning, cavitation and streaming were found depending on the file type and size, lateral canal location and irrigant used. In general, the IrriSafe file outperformed the K-file, and NaOCl performed better than the other irrigants tested. The cavitation and streaming measurements revealed that both contributed to hydrogel removal and both play a significant role in root canal cleaning.


Asunto(s)
Cavidad Pulpar/anatomía & histología , Tratamiento del Conducto Radicular , Irrigación Terapéutica , Terapia por Ultrasonido , Biopelículas , Humanos , Modelos Anatómicos , Irrigantes del Conducto Radicular , Preparación del Conducto Radicular
7.
Can J Physiol Pharmacol ; 95(2): 170-177, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27918843

RESUMEN

This study investigated the effect of aqueous extract of Cucurbita ficifolia Bouché on systemic chronic inflammation in an obesity model induced by monosodium glutamate (MSG) via modulating the expression of adipokines (TNF-α, IL-6, resistin, and adiponectin) and immune-regulatory cytokines (IFN-γ and IL-10). Cucurbita ficifolia extract was administered daily by gavage to lean and MSG-obese mice for 30 days. At the end of treatment, cytokine mRNA expression in adipose tissue was determined by real-time polymerase chain reaction (PCR), and the protein levels of these cytokines were also quantified by enzyme-linked immunosorbent assay (ELISA). Cucurbita ficifolia extract decreased body mass and inflammation in MSG-obese mice by reducing the expression of TNF-α and IL-6; these decreases were parallel to significant reductions in protein levels. The extract also increased protein levels of IL-10 in lean mice and IFN-γ in both lean and MSG-obese mice. In conclusion, C. ficifolia extract modulates systemic chronic inflammation in MSG-obese mice and could have a beneficial effect on the adaptive immune system in obesity.


Asunto(s)
Adipoquinas/biosíntesis , Cucurbita/química , Citocinas/biosíntesis , Mediadores de Inflamación/metabolismo , Interferón gamma/biosíntesis , Extractos Vegetales/farmacología , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Animales , Ratones , Obesidad/inducido químicamente , Obesidad/metabolismo , Extractos Vegetales/química , Glutamato de Sodio
8.
Am J Transplant ; 16(6): 1892-900, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26713513

RESUMEN

Abdominal wall transplantation (AWTX) has revolutionized difficult abdominal closure after intestinal transplantation (ITX). More important, the skin of the transplanted abdominal wall (AW) may serve as an immunological tool for differential diagnosis of bowel dysfunction after transplant. Between August 2008 and October 2014, 29 small bowel transplantations were performed in 28 patients (16 male, 12 female; aged 41 ± 13 years). Two groups were identified: the solid organ transplant (SOT) group (n = 15; 12 ITX and 3 modified multivisceral transplantation [MMVTX]) and the SOT-AWTX group (n = 14; 12 ITX and 2 MMVTX), with the latter including one ITX-AWTX retransplantation. Two doses of alemtuzumab were used for induction (30 mg, 6 and 24 h after reperfusion), and tacrolimus (trough levels 8-12 ng/mL) was used for maintenance immunosuppression. Patient survival was similar in both groups (67% vs. 61%); however, the SOT-AWTX group showed faster posttransplant recovery, better intestinal graft survival (79% vs. 60%), a lower intestinal rejection rate (7% vs. 27%) and a lower rate of misdiagnoses in which viral infection was mistaken and treated as rejection (14% vs. 33%). The skin component of the AW may serve as an immune modulator and sentinel marker for immunological activity in the host. This can be a vital tool for timely prevention of intestinal graft rejection and, more important, avoidance of overimmunosuppression in cases of bowel dysfunction not related to graft rejection.


Asunto(s)
Pared Abdominal/cirugía , Rechazo de Injerto/diagnóstico , Intestinos/trasplante , Complicaciones Posoperatorias , Síndrome del Intestino Corto/cirugía , Enfermedades de la Piel/patología , Adulto , Femenino , Rechazo de Injerto/etiología , Supervivencia de Injerto , Humanos , Masculino , Estudios Prospectivos , Síndrome del Intestino Corto/complicaciones , Enfermedades de la Piel/etiología , Resultado del Tratamiento
9.
Mol Cell Biochem ; 405(1-2): 257-64, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25912675

RESUMEN

The apoptosis of ß cells induced by hyperglycemia has been associated with p53 mobilization to mitochondria and p53 phosphorylation. Murine double minute 2 (Mdm2) induces the degradation of p53 and thereby protects cells from apoptosis. We studied the effect of glucose at high concentration on the ability of Mdm2 to ubiquitinate p53 and promote its degradation. RINm5F cells were grown in RPMI-1640 medium with 5 or 30 mM glucose for varying periods of time. After this treatment, the expression of Mdm2 was measured using real-time PCR. The phosphorylation of Mdm2 at Ser166, p53 at Ser15, and the kinases Akt and ATM were measured by Western blotting. The formation of the p53-Mdm2 complex and p53 ubiquitination was assessed by p53 immunoprecipitation and immunofluorescence. Our results showed that high glucose reduced Mdm2 mRNA expression and protein concentration and increased Mdm2 and Akt phosphorylation, albeit with slower kinetics for Akt. It also promoted p53-Mdm2 complex formation, whereas p53 ubiquitination was suppressed. Furthermore, phosphorylation of both p53 Ser15 and ATM was increased in the presence of 30 mM glucose. These data indicate that high concentration glucose decrease the mRNA expression and cytosolic concentration of Mdm2. However, although the increase in glucose promoted the phosphorylation of Mdm2, it also decreased p53 ubiquitination, thus avoiding p53 degradation. In hyperglycemic conditions, such as diabetes mellitus, the reduction of pancreatic ß cells mass is favored by stabilization of p53 in association with low p53 ubiquitination and reduced expression of Mdm2.


Asunto(s)
Glucosa/metabolismo , Hiperglucemia/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitinación/fisiología , Animales , Apoptosis/fisiología , Línea Celular Tumoral , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/fisiología , Mitocondrias/metabolismo , Mitocondrias/fisiología , Fosforilación/fisiología , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/genética , Ratas
10.
Br Poult Sci ; 56(1): 66-71, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25567139

RESUMEN

1. The aim of the present study was to evaluate the antimicrobial resistance of Campylobacter strains (C. jejuni, C. coli and C. lari) isolated from broiler carcasses processed in the State of Paraná, Brazil. 2. Rates of microbial resistance and susceptibility were assessed by both Disk Diffusion (DD) and Etest (Minimum Inhibitory Concentration) techniques. Antibiotics were tested using DD (12 antibiotics) and/or MIC (7 antibiotics) methods. 3. A total of 95.8% of the strains were resistant to at least two agents. In terms of multidrug resistance, 75% of strains were resistant to three or more groups of antibiotics. The highest rates of resistance were detected for cefalotin, ciprofloxacin, tetracycline and nalidixic acid. A high rate of susceptibility of the strains to erythromycin (95.8%) was found confirming that this is considered the agent of choice for treating campylobacteriosis. Comparison of the microbial resistance and susceptibility, as determined simultaneously by the two methods, found the techniques to be statistically equivalent for 5 out of the 6 antibiotics tested. 4. The results of this study suggest the need for adopting measures to control the use of antibiotics in broiler production to prevent multidrug resistance of Campylobacter strains and reduce the risk of serious human diseases caused by the consumption of contaminated chicken meat.


Asunto(s)
Antibacterianos/farmacología , Infecciones por Campylobacter/veterinaria , Campylobacter/efectos de los fármacos , Pollos , Farmacorresistencia Bacteriana Múltiple , Enfermedades de las Aves de Corral/microbiología , Animales , Infecciones por Campylobacter/epidemiología , Infecciones por Campylobacter/microbiología , Campylobacter coli/efectos de los fármacos , Campylobacter jejuni/efectos de los fármacos , Campylobacter lari/efectos de los fármacos , Pruebas Antimicrobianas de Difusión por Disco , Pruebas de Sensibilidad Microbiana , Enfermedades de las Aves de Corral/epidemiología
11.
Opt Express ; 22(23): 28467-78, 2014 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-25402089

RESUMEN

Recent studies on surface reflection illustrate how light beams can be laterally shifted from the position predicted by geometrical optics, the so called Goos-Hänchen effect. In antiferromagnets this shifts can be controlled with an external magnetic field. We show that a configuration in which spins cant in response to applied magnetic fields enhance possibilities of field controlled shifts. Moreover, we show that nonreciprocal displacements are possible, for both oblique and normal incidence, due to inherent nonreciprocity of the polariton phase with respect to the propagation direction. In the absence of an external field, reciprocal displacements occur.


Asunto(s)
Fenómenos Ópticos , Óptica y Fotónica/métodos , Campos Magnéticos
12.
Infection ; 42(6): 1023-32, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25263811

RESUMEN

BACKGROUND: The morbidity and mortality in hematopoietic stem cell transplantation (HSCT) occur due to infectious complications and constitute the major clinical problems in HSCT recipients. The role of the use of biomarkers in post-HSCT patients is still controversial. OBJECTIVES: To assess the serum values of biomarkers interleukin 6 (IL-6), procalcitonin (PCT) and C-reactive protein (CRP) and risk factors for post-HSCT death. PATIENTS AND METHODS: Prospective study conducted in patients submitted to HSCT at a university hospital. Biomarkers (IL-6, PCT and CRP) were assessed on the day afebrile neutropenia was detected, in the febrile event, 24 and 72 h after fever onset and 48 h or 5 days if fever persisted. Patients were compared as to the death outcome within 30 days from the HSCT. Variables with p < 0.15 were included in the multivariate analysis model (MVA) that were performed for all patients included in the study and separated for autologous and allogeneic HSCT patients. RESULTS: 296 patients with ages ranging between 15 and 70 years, neutropenic, submitted to HSCT, being 216 (73%) autologous and 80 (20%) allogeneic were assessed. One hundred and ninety (64.2%) patients presented fever after the transplantation and infection microbiologically controlled in 78 (26.4%). Twenty-three cases (7.8%) evolved to death. The risk factors associated with death in the bivariate analysis were age, allogeneic transplantation, unrelated transplantation, GVHD, bloodstream infection by Gram-negative, IL-6 >140 pg/mL and CRP ≥ 120 mg/L and the protective ones were lymphoma and hospital outpatient support. The independent variables in the MVA associated with death were allogeneic and unrelated transplantation, blood stream infection (BSI) by Gram-negative, LDH ≥ 390 UI/L, urea ≥ 25 mg/dL and CRP ≥ 120 mg/L for HSCT transplanted patients and BSI due to Gram-negative and CRP ≥ 120 mg/L for allogeneic HSCT, however, CRP ≥ 120 mg/L did not remain in the model when urea ≥ 25 mg/L was included. No independent risk factor was found for autologous patients. CONCLUSIONS: Out of the biomarkers assessed, only CRP ≥ 120 mg/L was independently associated with death. Other risk factors found were: type of transplantation (allogeneic and unrelated), bloodstream infection by Gram-negative, LDH ≥ 390 UI/L and urea ≥ 25 mg/dL. For allogeneic patients only CRP ≥ 120 mg/L and BSI due to Gram-negative were risk factors for death; however, CRP did not remain in the model when urea ≥ 25 mg/L was included.


Asunto(s)
Neutropenia Febril/sangre , Neutropenia Febril/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Adolescente , Adulto , Anciano , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Calcitonina/sangre , Péptido Relacionado con Gen de Calcitonina , Neutropenia Febril/diagnóstico , Femenino , Trasplante de Células Madre Hematopoyéticas/métodos , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Precursores de Proteínas/sangre , Factores de Riesgo , Adulto Joven
13.
Int Endod J ; 47(2): 147-54, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23701220

RESUMEN

AIM: To evaluate the effect of multiple refreshment/activation cycles and temperature on the reaction rate of sodium hypochlorite (NaOCl) with bovine dentine during ultrasonic activated irrigation (UAI) under laboratory conditions. METHODOLOGY: The root canal walls of 24 standardized root canals in bovine incisors were exposed to a standardized volume of NaOCl at different temperatures (24 °C and 38 °C) and exposure times (20, 60 and 180 s). The irrigant was refreshed and ultrasonically activated four times for 20 s followed by a 40 s rest interval, with no refreshment and no activation as the controls. The reaction rate was determined by measuring the amount of active chlorine in the NaOCl solution before and after being exposed to dentine during the specific experimental conditions. Calorimetry was used to measure the electrical-to-sonochemical conversion efficiency during ultrasonic activation. RESULTS: Refreshment, activation and exposure time all increased the reaction rate of NaOCl (P < 0.05). During activation, the temperature of the irrigant increased up to 10 °C. Such temperature rise was insufficient to enhance the reaction rate of NaOCl (P > 0.125). CONCLUSIONS: The reaction rate of NaOCl with dentine is enhanced by refreshment, ultrasonic activation and exposure time. Temperature rise of irrigant during ultrasonic activation was not sufficient to alter the reaction rate.


Asunto(s)
Dentina/efectos de los fármacos , Hipoclorito de Sodio/farmacología , Irrigación Terapéutica/métodos , Ultrasonido , Animales , Calorimetría , Bovinos , Cinética , Temperatura
14.
Int Endod J ; 47(11): 1040-51, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24397845

RESUMEN

AIM: To introduce and characterize a reproducible hydrogel as a suitable biofilm mimic in endodontic research. To monitor and visualize the removal of hydrogel from a simulated lateral canal and isthmus for the following: I) Ultrasonic-Activated Irrigation (UAI) with water, ii) UAI with NaOCl and iii) NaOCl without UAI. METHODOLOGY: A rheometer was used to characterize the viscoelastic properties and cohesive strength of the hydrogel for suitability as a biofilm mimic. The removal rate of the hydrogel from a simulated lateral canal or isthmus was measured by high-speed imaging operating at frame rates from 50 to 30,000 fps. RESULTS: The hydrogel demonstrated viscoelastic behaviour with mechanical properties comparable to real biofilms. UAI enhanced the cleaning effect of NaOCl in isthmi (P < 0.001) and both NaOCl and water in lateral canals (P < 0.001). A greater depth of cleaning was achieved from an isthmus (P = 0.009) than from a lateral canal with UAI and also at a faster rate for the first 20 s. NaOCl without UAI resulted in a greater depth of hydrogel removal from a lateral canal than an isthmus (P < 0.001). The effect of UAI was reduced when stable bubbles were formed and trapped in the lateral canal. Different removal characteristics were observed in the isthmus and the lateral canal, with initial highly unstable behaviour followed by slower viscous removal inside the isthmus. CONCLUSIONS: The biofilm-mimicking hydrogel is reproducible, homogenous and can be easily applied and modified. Visualization of its removal from lateral canal anatomy provides insights into the cleaning mechanisms of UAI for a biofilm-like material. Initial results showed that UAI improves hydrogel removal from the accessory canal anatomy, but the creation of stable bubbles on the hydrogel-liquid interface may reduce the cleaning rate.


Asunto(s)
Biopelículas , Hidrogeles , Tratamiento del Conducto Radicular , Irrigación Terapéutica
16.
Res Q Exerc Sport ; 93(2): 379-390, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-33297869

RESUMEN

Purpose: To date, most research on the assessment of motivation has been exerciser-focused and has not considered how fitness professionals' motivations impact their behaviors toward exercisers during training sessions. The purpose of this study was to examine the factor structure of the Coach Motivation Questionnaire in a sample of fitness professionals (CMQ-FP) to ascertain its usefulness for this vocational grouping. Measurement invariance analysis was conducted between female and male fitness professionals, and predictive validity was tested considering need-supportive and need-thwarting behaviors as outcomes. Methods: Participants were 799 fitness professionals (female = 412) aged between 20 and 56 years (M = 28.71, SD = 3.24), who completed a multi-section survey assessing their motivation toward work and their interpersonal behaviors when engaging with exercisers. Results: The results of this research supported all three hypotheses. First, the hypothesized 6-factor measurement model showed acceptable fit to the data. Second, the factor structure of the CMQ-FP was invariant across gender (male and female fitness professionals). Third, fitness professionals' (autonomous or controlled) motivation was a valid predictor of need-supportive or need-thwarting behaviors. Conclusion: This study supported the factor structure of the CMQ-FP, presenting as a valid measure of motivation in fitness professionals. Understanding fitness professionals' perceptions of their coaching motivation can inform professional development activities to assist fitness professionals to increase understanding of what motivates these professionals and how they might be more need-supportive and less need-thwarting in their pedagogical behaviors.


Asunto(s)
Tutoría , Motivación , Adulto , Ejercicio Físico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Autonomía Personal , Encuestas y Cuestionarios , Adulto Joven
17.
Pulmonology ; 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35219623

RESUMEN

INTRODUCTION AND OBJECTIVES: Nontuberculous mycobacteria (NTM) are opportunistic human pathogens found in the environment. The transmission seems to be associated with inhalation of aerosol droplets, ingestion or trauma events. Recent studies indicate that NTM disease is increasing worldwide, however, the true clinical impact of NTM infections is difficult to determine due to challenges in discriminating between disease and colonization as they are ubiquitous in the environment. In addition, understanding the epidemiology of NTM is difficult and has not yet been established. In this work, we used a country NTM representative collection from the National Reference Laboratory for Tuberculosis (NRL-TB) of the National Institute of Health (INSA), to characterize the circulation trends of NTM species in Portugal and the most affected regions, contributing to a better understanding of the NTM epidemiology. MATERIAL AND METHODS: We conducted a nationwide retrospective study where all individuals with positive NTM cultures at the NRL-TB of the INSA from 2014 to December 2020 were included. Positive cultures were identified using GenoType Mycobacterium CM/AS® (Hain Lifescience) according to manufacturer's instructions, or hsp65 DNA sequencing as previously described. Social-demographic data from patients were also analyzed and patients classified into 3 groups according only to microbiological data, "definite NTM disease", "NTM colonization" and, "possible NTM disease". RESULTS: In the period 2014-2020, the NRL-TB performed 50397 cultures. Among these, 1118 cultures were NTM positive retrieved from 944. Most of our cases were in patients whose mean age was 64±15.9 years, and no significant differences between gender was observed, although more frequent in male patients. Overall, from the 944 cases, we were able to identified 93 "definite NTM disease" cases and 79 "possible NTM disease". Mycobacterium avium complex (MAC) (40,8%), Mycobacterium abscessus-chelonae complex (MABC) (9,6%) and Mycobacterium fortuitum (6,3%) were responsible for most of the infections. The geographical distribution of NTM cases varied significantly and was possible to observe that was independent of population density. The region were most cases occurred was Lisbon Metropolitan Area (31,9%), followed by North (25,3%) and Centre (24,4%), however North region has the highest number of "definite NTM disease" cases (n=33). CONCLUSIONS: This is the first national wide epidemiological study on this subject, contributing to a better understanding of NTM dynamics in Portugal. MAC was the NTM species responsible for the majority of infections and, LMA the region with the highest number of cases. It was also possible to conclude that the number of NTM isolates is independent of the demography of the region.

18.
Biomed J ; 45(4): 654-664, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34314900

RESUMEN

BACKGROUND: Tuberculosis (TB) is a disease with worldwide presence and a major cause of death in several developing countries. Current diagnostic methodologies often lack specificity and sensitivity, whereas a long time is needed to obtain a conclusive result. METHODS: In an effort to develop better diagnostic methods, this study aimed at the discovery of a biomarker signature for TB diagnosis using a Nuclear Magnetic Resonance based metabolomics approach. In this study, we acquired 1H NMR spectra of blood serum samples of groups of healthy subjects, individuals with latent TB and of patients with pulmonary and extra-pulmonary TB. The resulting data were treated with uni- and multivariate statistical analysis. RESULTS: Six metabolites (inosine, hypoxanthine, mannose, asparagine, aspartate and glutamate) were validated by an independent cohort, all of them related with metabolic processes described as associated with TB infection. CONCLUSION: The findings of the study are according with the WHO Target Product Profile recommendations for a triage test to rule-out active TB.


Asunto(s)
Ácido Aspártico , Tuberculosis , Asparagina , Biomarcadores , Glutamatos , Humanos , Hipoxantinas , Inosina , Espectroscopía de Resonancia Magnética , Manosa , Metabolómica/métodos , Tuberculosis/diagnóstico
19.
Br J Oral Maxillofac Surg ; 59(5): 573-578, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33518396

RESUMEN

The objective of this study was to assess the resorption index of particulate calvarial grafts in maxillary sinuses of patients undergoing total reconstruction of an atrophic maxilla with residual alveolar bone that was less than, or equal to, 3mm thick. Twenty-one maxillary sinus floor elevations were carried out using particulate calvarial grafts in 11 individuals with totally edentulous maxillas. All patients had computed tomography (CT) before (T0), and 48hours (T1) and six months after surgery (T2). For each CT scan, linear measurements were taken of sections of the anterior, medial, and posterior regions of the maxillary sinus. There was a significant increase in the height of the maxillary sinus floor when T0 was compared with T1 (p=0.001). There was a statistically significant reduction in all maxillary sinus measurements when T1 was compared with T2; the mean height reduction being 2.36mm (16.87%) in the anterior region, 3.53mm (22.47%) in the medial region, and 2.21mm (22.78%) in the posterior region (p=0.001). Mean resorption was 20.7%. Autogenous calvarial bone used alone is an option for graft material in pneumatised maxillary sinuses and in cases where there is limited alveolar bone.


Asunto(s)
Implantes Dentales , Elevación del Piso del Seno Maxilar , Trasplante Óseo , Implantación Dental Endoósea , Humanos , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/cirugía , Estudios Prospectivos
20.
Polymers (Basel) ; 13(3)2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33494537

RESUMEN

Among smart materials, self-healing is one of the most studied properties. A self-healing polymer can repair the cracks that occurred in the structure of the material. Polyketones, which are high-performance thermoplastic polymers, are a suitable material for a self-healing mechanism: a furanic pendant moiety can be introduced into the backbone and used as a diene for a temperature reversible Diels-Alder reaction with bismaleimide. The Diels-Alder adduct is formed at around 50 °C and broken at about 120 °C, giving an intrinsic, stimuli-responsive self-healing material triggered by temperature variations. Also, reduced graphene oxide (rGO) is added to the polymer matrix (1.6-7 wt%), giving a reversible OFF-ON electrically conductive polymer network. Remarkably, the electrical conductivity is activated when reaching temperatures higher than 100 °C, thus suggesting applications as electronic switches based on self-healing soft devices.

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