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2.
Vet Parasitol ; 324: 110069, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37984155

RESUMEN

Although ivermectin (IVM) has a wide spectrum and long half-life, its frequent use as an anthelmintic for the last 42 years led to its worldwide tolerance by Haemonchus contortus. We evaluated the combination of limonene (LIM), a P-glycoprotein (Pgp) modulator, with IVM in lambs infected with a multidrug-resistant H. contortus. Twenty-four male Dorper lambs were artificially infected with two doses (seven days apart) of 8000 infective larvae of a multidrug-resistant isolate of H. contortus. The infection was patent 25 days later. Fifteen days before treatment with IVM (DAY -15), animals were divided into 4 groups: Infected-untreated control (CTL), IVM, LIM, and LIM+IVM. From DAY -15 to DAY + 14, groups LIM and LIM+IVM received 200 mg/kg of body weight/day of LIM via oral. On DAY 0, a single dose of IVM at 200 µg/kg of body weight was administered orally to groups IVM and LIM+IVM. On DAY + 7 and DAY + 14, fecal egg counts (FEC) were performed and on DAY + 14 animals were euthanized for total worm count (TWC), worm length, fecundity of females, and Pgp-9 gene expression. On DAY + 7, group LIM+IVM had 96.29% efficacy based on Fecal Egg Count Reduction TEST (FECRT) and a highly significant reduction in FEC (P = 0.0005) when compared to CTL. On DAY + 14, the efficacy of LIM+IVM was 82.87% on FECRT, although no differences were found among groups for FEC, TWC, worm length, or Pgp-9 gene expression. Female worms from the CTL group had higher egg counts in their uterus when compared to LIM. No differences were found for hematological or biochemical parameters, body weight, or weight gain among groups. Thus, LIM given daily at 200 mg/kg was safe for animals and, when combined with IVM, decreased egg shedding and could reduce pasture contamination, although it was unable to kill multidrug-resistant H. contortus.


Asunto(s)
Antihelmínticos , Hemoncosis , Haemonchus , Enfermedades de las Ovejas , Ovinos , Animales , Femenino , Masculino , Ivermectina/farmacología , Ivermectina/uso terapéutico , Haemonchus/genética , Limoneno/farmacología , Óvulo , Antihelmínticos/farmacología , Antihelmínticos/uso terapéutico , Oveja Doméstica , Peso Corporal , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Expresión Génica , Hemoncosis/tratamiento farmacológico , Hemoncosis/veterinaria , Enfermedades de las Ovejas/tratamiento farmacológico , Heces , Recuento de Huevos de Parásitos/veterinaria
3.
Sci Total Environ ; 859(Pt 1): 160132, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36400291

RESUMEN

The present study employed data collected during the Mycosands survey to investigate the environmental factors influencing yeasts and molds distribution along European shores applying a species distribution modelling approach. Occurrence data were compared to climatic datasets (temperature, precipitation, and solar radiation), soil datasets (chemical and physical properties), and water datasets (temperature, salinity, and chlorophyll-a concentration) downloaded from web databases. Analyses were performed by MaxEnt software. Results suggested a different probability of distribution of yeasts and molds along European shores. Yeasts seem to tolerate low temperatures better during winter than molds and this reflects a higher suitability for the Northern European coasts. This difference is more evident considering suitability in waters. Both distributions of molds and yeasts are influenced by basic soil pH, probably because acidic soils are more favorable to bacterial growth. Soils with high nitrogen concentrations are not suitable for fungal growth, which, in contrast, are optimal for plant growth, favored by this environment. Finally, molds show affinity with soil rich in nickel and yeasts with soils rich in cadmium resulting in a distribution mainly at the mouths of European rivers or lagoons, where these metals accumulate in river sediments.


Asunto(s)
Ríos , Contaminantes del Suelo , Ríos/química , Suelo/química , Cadmio/análisis , Contaminantes del Suelo/análisis , Metales/análisis , Levaduras , Monitoreo del Ambiente
4.
Infect Dis Now ; 53(2): 104633, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36375764

RESUMEN

OBJECTIVE: Aspergillosis diagnosis depends on the detection of Aspergillus in biological samples ─ usually using cultural and immunoenzyme techniques ─ but their sensitivity and specificity varies. We aimed to study the prevalence of Aspergillus in patients at higher risk of chronic pulmonary aspergillosis (i.e., HIV-infected patients and individuals with active or previous tuberculosis), and to determine the potential role of molecular approaches to increase detection of Aspergillus in respiratory samples. METHODS: The DNA extracted from 43 respiratory samples that had been previously analyzed by immunoenzyme and/or cultural techniques was amplified by real-time multiplex PCR, and the results of these methods were compared. We also sequenced the ITS1 region and the calmodulin gene in 10 respiratory samples to perform a pilot metagenomic study to understand the ability of this methodology to detect potential pathogenic fungi in the lung mycobiome. RESULTS: Real-time Aspergillus PCR test exhibited a higher positivity rate than the conventional techniques used for aspergillosis diagnosis, particularly in individuals at risk for chronic pulmonary aspergillosis. The metagenomic analysis allowed for the detection of various potentially pathogenic fungi. CONCLUSIONS: Molecular techniques, including metagenomics, have great ability to detect potentially pathogenic fungi rapidly and efficiently in human biological samples.


Asunto(s)
Aspergilosis , Aspergilosis Pulmonar , Humanos , Aspergillus/genética , Aspergilosis Pulmonar/diagnóstico , Aspergilosis Pulmonar/epidemiología , Aspergilosis/diagnóstico , Sensibilidad y Especificidad
5.
Dent Mater ; 38(8): 1404-1418, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35787894

RESUMEN

OBJECTIVE: Evaluate the effect of different restorative filling techniques on the residual shrinkage stress (ShrS), cuspal strain (CS), depth of cure (DC), and enamel crack formation (Ec) in molars with MOD restorations. METHODS: Post-gel shrinkage, elastic modulus, compressive and diametral tensile strength of the Filtek One Bulk Fill composite were calculated. Sixty molars with MOD preparations were restored using four filling techniques: Bulk; Horizontal; Oblique; Natural enamel and dentin substitution (NEDS) technique. CS was measured using a strain gauge (n = 10). The DC (n = 5) was measured using Knoop hardness. Shrinkage stress/strain was analyzed using 3D finite element analysis. The Ec analysis was carried out by transillumination. Two-way ANOVA with repeated measures and Tukey's HSD test (α = 0.05) was performed for the CS data. Two-Way ANOVA and Tukey's HSD test was performed for the DC data (α = 0.05). RESULTS: CS was higher at the lingual cusp for the horizontal and NEDS technique. No statistical difference was found between the buccal and lingual CS values for the Bulk (p = 0.367) or Oblique techniques (p = 0.192). CS values were lower for the Bulk. More enamel cracks were found for the Bulk. DC was lower at 4 mm regardless the filling technique. The Horizontal showed the highest ShrS values. The Bulk generated the lower ShrS values. SIGNIFICANCE: A Bulk technique caused the lowest shrinkage stress/strain. An Oblique technique yielded the best balance between stress, strain and crack formation. NEDS technique is a good alternative to decrease the number of increments while maintaining the stress levels nearby the Oblique technique.


Asunto(s)
Resinas Compuestas , Restauración Dental Permanente , Esmalte Dental , Restauración Dental Permanente/métodos , Análisis del Estrés Dental , Ensayo de Materiales , Diente Molar , Polimerizacion
6.
BMC Psychol ; 10(1): 36, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35193693

RESUMEN

BACKGROUND: Depressive symptomatology is prevalent among female university students with adverse effects on their quality of life and academic performance. Previous research suggested associations between depressive symptomatology and oxytocin levels and between depressive symptomatology and Temperament Traits. Despite this evidence, to the best of our knowledge no research has studied the effects fboth oxytocin serum levels and temperament dimensions on depressivesymptoms in a healthy sample. The present study aimed to analyse the effect of oxytocin levels and temperament traits on depressive symptomatology in healthy female university students. METHODS: All participants completed the Beck Depression Inventory and the Adult Temperament Questionnaire. Blood samples were collected between 8 and 8H30 a.m. after 12 h of fasting and between 5 and 8 day of the menstrual cycle and serum oxytocin levels were quantified using a commercial enzyme-linked immunosorbent assay. A hierarchical multiple regression model using a stepwise method was conducted to identify predictors of depression. RESULTS: Forty-five women aged between 18 and 25 years old (19.37 ± 1.32 years) volunteered to participate in this study. Depressive symptomatology was negatively associated with oxytocin serum levels and "Negative affect" and positively associated with "Effortful control" and "Activation Control". In the final regression model, only oxytocin level was a predictor (B = - 0.090, p < 0.0001), the model explaining 65.2% of the depression variation. Oxytocin played a mediation role between "Negative affects" and Depressive symptomatology. CONCLUSIONS: Our results showed that oxytocin level, rather than personality dimensions, was associated with depressive symptomatology. These results highlight the relevance of the discussion on the use of oxytocin as a biological marker of emotional and social symptoms that characterize depression.


Asunto(s)
Depresión/epidemiología , Oxitocina , Temperamento , Adolescente , Adulto , Femenino , Humanos , Oxitocina/sangre , Inventario de Personalidad , Calidad de Vida , Estudiantes/psicología , Universidades , Adulto Joven
7.
Sci Total Environ ; 781: 146598, 2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-33812107

RESUMEN

The goal of most studies published on sand contaminants is to gather and discuss knowledge to avoid faecal contamination of water by run-offs and tide-retractions. Other life forms in the sand, however, are seldom studied but always pointed out as relevant. The Mycosands initiative was created to generate data on fungi in beach sands and waters, of both coastal and freshwater inland bathing sites. A team of medical mycologists and water quality specialists explored the sand culturable mycobiota of 91 bathing sites, and water of 67 of these, spanning from the Atlantic to the Eastern Mediterranean coasts, including the Italian lakes and the Adriatic, Baltic, and Black Seas. Sydney (Australia) was also included in the study. Thirteen countries took part in the initiative. The present study considered several fungal parameters (all fungi, several species of the genus Aspergillus and Candida and the genera themselves, plus other yeasts, allergenic fungi, dematiaceous fungi and dermatophytes). The study considered four variables that the team expected would influence the results of the analytical parameters, such as coast or inland location, urban and non-urban sites, period of the year, geographical proximity and type of sediment. The genera most frequently found were Aspergillus spp., Candida spp., Fusarium spp. and Cryptococcus spp. both in sand and in water. A site-blind median was found to be 89 Colony-Forming Units (CFU) of fungi per gram of sand in coastal and inland freshwaters, with variability between 0 and 6400 CFU/g. For freshwater sites, that number was 201.7 CFU/g (0, 6400 CFU/g (p = 0.01)) and for coastal sites was 76.7 CFU/g (0, 3497.5 CFU/g). For coastal waters and all waters, the median was 0 CFU/ml (0, 1592 CFU/ml) and for freshwaters 6.7 (0, 310.0) CFU/ml (p < 0.001). The results advocate that beaches should be monitored for fungi for safer use and better management.


Asunto(s)
Playas , Arena , Australia , Mar Negro , Hongos , Humanos , Italia , Microbiología del Agua
8.
Sci Total Environ ; 740: 140237, 2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-32927553

RESUMEN

Thirty people (mostly children) experienced an episode of skin rash days after a sand sifting beach operation at Porto Pim Beach in Faial, Azores during June 2019. An environmental and epidemiologic investigation was conducted to identify the cause of the outbreak of skin rash. The epidemiologic investigation found that some of the patients experiencing symptoms had never entered the beach water. During the pollution period and throughout the epidemiologic investigation, faecal indicator bacteria levels (94 CFU/100 ml for intestinal enterococci and 61 CFU/100 ml for Escherichia coli) in water remained under the limits used for the ninety-five percentile calculation of an Excellent coastal and transitional bathing water defined in the Portuguese Legislation (100 CFU/100 ml for intestinal enterococci and 250 CFU/100 ml for Escherichia coli). Thus sand contact was considered as a likely primary exposure route. Sand microbiological analysis for faecal indicator organisms and electron microscopy strongly suggested faecal contamination. Chemical analysis of the sand also revealed a concomitant substance compatible with sodium-hypochlorite as analysed using gas chromatography and subsequently confirmed by free chlorine analysis. Inspection of the toilet facilities and sewage disposal system revealed a leaking sewage distribution box. Collectively, results suggest that the cause of the outbreak was the leaking underground sewage distribution box that serviced the beach toilet facilities (40 m from beach), where sodium-hypochlorite was used for cleaning and disinfection. This sewage then contaminated the surficial sands to which beach goers were exposed. Chlorine being an irritant substance, was believed to have been the cause of the symptoms given the sudden presentation and dissipation of skin rashes. No gastro-intestinal illness was reported during this episode and during the following 30 days. Like water, beach sand should also be monitored for safety, especially for areas serviced by aged infrastructure.


Asunto(s)
Playas , Aguas del Alcantarillado , Azores , Niño , Monitoreo del Ambiente , Heces , Humanos , Arena , Microbiología del Agua
9.
Oper Dent ; 45(5): E217-E226, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32352352

RESUMEN

CLINICAL RELEVANCE: The clinician should consider the polymerization shrinkage stress when selecting a composite resin for posterior restorations. The use of post-gel shrinkage values should guide the selection of a composite resin for posterior teeth. SUMMARY: Objectives: The objective of this study was to evaluate the effect of the method used for calculation of polymerization shrinkage, total or post-gel, on the shrinkage stress of conventional and bulk-fill composite resins for restoring endodontically treated teeth using finite element analysis.Methods and Materials: Four composite resins were tested for post-gel shrinkage (P-Shr) by the strain-gauge test and total shrinkage (TShr) using an optical method (n=10). Two conventional composite resins, Filtek Z350 XT (3M-ESPE; Z350) and TPH3 Spectrum (Dents-ply; TPH3) and two bulk-fill composite resins. Filtek Bulk-Fill Posterior (3M-ESPE; POST) SureFil SDR flow (Dentsply; SDR) were tested. Elastic modulus (E), diametral tensile strength (DTS), and compressive strength (CS) were also determined (n=10). The residual shrinkage stress was evaluated by finite element analysis with four restorative techniques: incremental with Z350 and TPH3; SDR/TPH3 (two bulk increments of 4 mm and two occlusal increments); and two bulk increments of 5 mm for POST. Data for P-Shr, T-Shr, E, DTS, and CS were analyzed by analysis of variance and Tukey's test (α=0.05), and residual shrinkage was analyzed quantitatively and qualitatively by the modified von Mises criteria.Results: SDR had the lowest CS values, POST and TPH3 had similar and intermediate values, and Z350 had the highest CS. TPH3 and Z350 had similar DTS values and values higher than SDR. Z350 and POST had higher P-Shr, and SDR had lower T-Shr. T-Shr resulted in higher shrinkage stress than P-Shr values. SDR/TPH3 resulted in higher shrinkage stress when using T-Shr and lower values when using the P-Shr value.Conclusion: T-Shr resulted in higher stress in the enamel and in root dentin close to the pulp chamber than P-Shr values. The selection of the T-Shr or P-Shr changed the ranking of the shrinkage stress of the tested composite resin.


Asunto(s)
Resinas Compuestas , Diente Molar , Análisis del Estrés Dental , Ensayo de Materiales , Polimerizacion , Resistencia a la Tracción
10.
Exp Parasitol ; 197: 36-42, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30633915

RESUMEN

Molecules from natural sources, such as essential oils, have shown activity against parasites in vitro, but have not yet been explored extensively in vivo. Anethole and carvone (10% each), encapsulated with 80% of a solid matrix, referred to as EO (encapsulated oils), were tested in vivo in 2 experiments. In Experiment 1: Lambs were artificially infected with multidrug resistant Haemonchus contortus, or left uninfected, and treated (or not) with 50 mg/kg bw (body weight) of EO in a controlled environment. Thirty-two male lambs were kept in individual cages for a period of 45 days, after which animals were evaluated for parasitological, hematological, toxicological, and nutritional parameters. After 45 days of treatment, EO at 50 mg/kg bw provided a significant (P ≤ 0.05) reduction in fecal egg count (FEC). Although FEC was reduced, animals from both treatments had similar counts of total adult worms. The low FEC was caused probably by a significant reduction (P ≤ 0.05) in both male worm size and female fecundity. Dry matter intake of uninfected controls was significantly (P ≤ 0.05) reduced, although no toxicity was observed in treated animals. Thus, in Experiment 2, conducted for five months we used an EO dose of 20 mg/kg bw. Thirty-four weaned lambs, free of parasites, were divided in two groups and kept in collective pens. One group received EO at 20 mg/kg bw mixed with concentrate for 5 months and the other was kept as a control group (CTL). Parasitological and hematological parameters as well as body weight were evaluated. In the first 2.5 months, CTL and EO groups were confined, and both presented similar clinical parameters. Then, animals were allotted to graze on contaminated pastures to acquire natural infection for the next 2.5 months. The infection was patent after 25 days and both groups had similar decreases in weight gain, increases in FEC, and decreases in blood parameters. Coprocultures from CTL and EO groups established that parasite population was 90% Haemonchus sp. We concluded that the technology of encapsulation is safe and practical to deliver to lambs at the farm level and anethole and carvone at 50 mg/kg bw caused a significant decrease in FEC and, consequently, in pasture contamination by free living stages of H. contortus. However, EO at 20 mg/kg bw was not effective to prevent or treat sheep naturally-infected with gastrointestinal nematodes.


Asunto(s)
Anisoles/uso terapéutico , Hemoncosis/veterinaria , Monoterpenos/uso terapéutico , Enfermedades de las Ovejas/tratamiento farmacológico , Enfermedades de las Ovejas/parasitología , Abomaso/parasitología , Derivados de Alilbenceno , Animales , Anisoles/administración & dosificación , Anisoles/química , Aspartato Aminotransferasas/sangre , Cápsulas , Creatinina/sangre , Monoterpenos Ciclohexánicos , Resistencia a Múltiples Medicamentos , Sinergismo Farmacológico , Ingestión de Alimentos , Recuento de Eritrocitos/veterinaria , Heces/parasitología , Femenino , Fertilidad , Hemoncosis/tratamiento farmacológico , Hemoncosis/parasitología , Haemonchus/efectos de los fármacos , Haemonchus/crecimiento & desarrollo , Haemonchus/fisiología , Masculino , Monoterpenos/administración & dosificación , Monoterpenos/química , Recuento de Huevos de Parásitos/veterinaria , Distribución Aleatoria , Ovinos , Urea/sangre , Aumento de Peso , gamma-Glutamiltransferasa/sangre
11.
Parasitol Res ; 117(3): 705-712, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29327323

RESUMEN

Albendazole (ABZ), a benzimidazole widely used to control gastrointestinal parasites, is poorly soluble in water, resulting in variable and incomplete bioavailability. This has favored the appearance ABZ-resistant nematodes and, consequently, an increase in its clinical ineffectiveness. Among the pharmaceutical techniques developed to increase drug efficacy, cyclodextrins (CDs) and other polymers have been extensively used with water-insoluble pharmaceutical drugs to increase their solubility and availability. Our objective was to prepare ABZ formulations, including ß-cyclodextrin (ßCD) or hydroxypropyl-ß-cyclodextrin (HPßCD), associated or not to the water-soluble polymer polyvinylpyrrolidone (PVP). These formulations had their solubility and anthelmintic effect both evaluated in vitro. Also, their anthelmintic efficacy was evaluated in lambs naturally infected with gastrointestinal nematodes (GIN) through the fecal egg count (FEC) reduction test. In vitro, the complex ABZ/HPßCD had higher solubility than ABZ/ßCD. The addition of PVP to the complexes increased solubility and dissolution rates more effectively for ABZ/HPßCD than for ABZ/ßCD. In vivo, 48 lambs naturally infected with GIN were divided into six experimental groups: control, ABZ, ABZ/ßCD, ABZ/ßCD-PVP, ABZ/HPßCD, and ABZ/HPßCD-PVP. Each treated animal received 10 mg/kg of body weight (based on the ABZ dose) for three consecutive days. After 10 days of the last administered dose, treatment efficacy was calculated. The efficacy values were as follows: ABZ (70.33%), ABZ/ßCD (85.33%), ABZ/ßCD-PVP (82.86%), ABZ/HPßCD (78.37%), and ABZ/HPßCD-PVP (43.79%). In vitro, ABZ/HPßCD and ABZ/HPßCD-PVP had high solubility and dissolution rates. In vivo, although the efficacies of ABZ/ßCD, ABZ/ßCD-PVP, and ABZ/HPßCD increased slightly when compared to pure ABZ, this increase was not significant (P > 0.05).


Asunto(s)
Albendazol/farmacocinética , Antiparasitarios/farmacocinética , Ciclodextrinas/farmacocinética , Nanopartículas/química , Povidona/farmacocinética , 2-Hidroxipropil-beta-Ciclodextrina/química , 2-Hidroxipropil-beta-Ciclodextrina/farmacocinética , Albendazol/química , Animales , Antihelmínticos/química , Antihelmínticos/farmacocinética , Antiparasitarios/química , Disponibilidad Biológica , Ciclodextrinas/química , Composición de Medicamentos , Parasitosis Intestinales/tratamiento farmacológico , Parasitosis Intestinales/veterinaria , Masculino , Nematodos , Infecciones por Nematodos/tratamiento farmacológico , Infecciones por Nematodos/veterinaria , Povidona/química , Ovinos , Enfermedades de las Ovejas/tratamiento farmacológico , Enfermedades de las Ovejas/parasitología , Solubilidad , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacocinética
12.
J Food Sci Technol ; 54(13): 4344-4352, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29184240

RESUMEN

Most studies evaluating the use of essential oils (EO) as antibacterial agents focus mainly on minimal inhibitory concentrations (MIC) rather than minimal bactericidal concentrations (MBC). In this work, we compared MICs and MBCs of EO from condiment plants commonly used in Mediterranean Europe, namely Origanum vulgare, Salvia lavandulaefolia, Salvia officinalis, Salvia sclarea and Rosmarinus officinalis, aiming to evaluate their application as disinfecting agents in minimally processed produce. Outbreaks-related pathogens such as Listeria monocytogenes, Pseudomonas aeruginosa and Yarrowia lipolytica were used. Results showed that all EO were able to reduce bacterial growth in all bacterial strains tested, particularly O. vulgare. However, fewer EO exhibited bactericidal activities, and were only effective against one or two bacterial strains, hence eliminating the possibility to use them as broad range disinfectants. Furthermore, the necessary concentrations were too high for food application. Hence, our work suggests the need to evaluate MBC rather than MIC and questions EO usefulness in controlling undesired microorganisms. Overall, and despite the large volume of data published on EO, results obtained were not very encouraging for a realistic application on produce and question the viability of EOs as disinfecting agents in food.

13.
Oper Dent ; 42(6): 646-657, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28976843

RESUMEN

OBJECTIVES: To evaluate the effects of direct composite resin without a post or with one or two fiberglass posts on the restoration of severely compromised endodontically treated molars. METHODS AND MATERIALS: Forty-five molars with 2 mm of "remaining tooth structure" were divided into three groups: Wfgp, restored with Filtek Z350XT without a fiberglass post; 1fgp, restored with Z350XT with one fiberglass post in the distal root canal; and 2fgp, restored with Z350XT with two fiberglass posts, one in the distal root canal and the other in the mesial-buccal root canal. The teeth were load cycled. Tooth remaining strain was measured using strain gauges (n=10) at two moments: TrSt-100 N, during 100 N occlusal loading, and TrSt-Fr, at fracture load. Fracture resistance was calculated, and fracture mode was classified. The elastic modulus and Vickers hardness were calculated using dynamic indentation (n=5). Stress distribution was analyzed by three-dimensional finite element analysis. RESULTS: The use of two fiberglass posts resulted in lower fracture resistance than was noted in the groups with one fiberglass post and without fiberglass posts. The lingual surface of the remaining tooth had higher strain values than the buccal surface, regardless of the restorative technique and moment of evaluation. The absence of a fiberglass post resulted in significantly higher strain values and more irreparable fracture modes than were noted in the other groups. The use of one fiberglass post had a better strain/fracture resistance ratio. Stresses were concentrated in the occlusal portion of the post and in the furcation region. The presence of one fiberglass post resulted in better stress distribution in the entire distal root dentin, reducing stress on the critical areas. CONCLUSIONS: The use of one fiberglass post for restoring molars with direct composite resin resulted in higher fracture resistance than did the use of two fiberglass posts; it also resulted in better tooth remaining strain and stress distribution and more reparable fracture modes than were seen in the group without a fiberglass post.


Asunto(s)
Resinas Compuestas/uso terapéutico , Restauración Dental Permanente/métodos , Diente Molar/fisiopatología , Técnica de Perno Muñón , Diente no Vital/fisiopatología , Fracaso de la Restauración Dental , Restauración Dental Permanente/efectos adversos , Análisis del Estrés Dental , Humanos , Técnicas In Vitro , Técnica de Perno Muñón/efectos adversos , Fracturas de los Dientes/etiología , Fracturas de los Dientes/prevención & control
14.
Vet Parasitol ; 246: 118-123, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-28969774

RESUMEN

Haemonchus contortus is the most important nematode in small ruminant systems, and has developed tolerance to all commercial anthelmintics in several countries. In vitro (egg hatch assay) and in vivo tests were performed with a multidrug strain of Haemonchus contortus using Terminalia catappa leaf, fruit pulp, and seed extracts (in vitro), or pulp and seed powder in lambs experimentally infected with H. contortus. Crude extracts from leaves, fruit pulp and seeds obtained with 70% acetone were lyophilized until used. In vitro, the extracts had LC50=2.48µg/mL (seeds), LC50=4.62µg/mL (pulp), and LC50=20µg/mL (leaves). In vitro, seed and pulp extracts had LC50 similar to Thiabendazole (LC50=1.31µg/mL). Condensed tannins were more concentrated in pulp extract (183.92g of leucocyanidin/kg dry matter) than in either leaf (4.6g) or seed (35.13g) extracts. Phytochemical tests established that all extracts contained alkaloids, flavonoids, saponins, phenols, and terpenoids. Based on these results, in vivo tests were performed to evaluate the anthelmintic activity of T. catappa whole fruit (pulp+seed) powder. Male Santa Ines lambs were artificially infected with multidrug-resistant H. contortus and divided, according to similar fecal egg count (FEC) and weight, into two groups: Control (infected/untreated) and treated (infected/treated with whole fruit powder). Whole fruit powder was mixed with concentrate and provided at 2g/kg of body weight (BW) for five days. After treatment, parasitological analysis (FEC and egg hatch assay), renal profile (urea and creatinine), liver profile (aspartate aminotransferase) and BW were determined. In vitro (based on LC50), seed/pulp extracts had ovicidal effect similar to Thiabendazole but whole fruit powder had no anthelmintic effect on adult nematodes in the abomasum. We discuss the plausible causes of the lack of in vivo activity.


Asunto(s)
Hemoncosis/tratamiento farmacológico , Hemoncosis/veterinaria , Extractos Vegetales/uso terapéutico , Enfermedades de las Ovejas/parasitología , Terminalia/química , Animales , Antihelmínticos/uso terapéutico , Frutas , Haemonchus/efectos de los fármacos , Masculino , Recuento de Huevos de Parásitos/veterinaria , Fitoterapia , Extractos Vegetales/química , Hojas de la Planta/química , Semillas/química , Ovinos , Enfermedades de las Ovejas/tratamiento farmacológico
15.
Vet Parasitol ; 243: 47-51, 2017 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-28807309

RESUMEN

Anthelmintic resistance in sheep gastrointestinal nematodes is a worldwide problem. Multi-drug resistant haemonchosis is the most serious impediment for small ruminant systems, and there are no new drug candidates currently under development. Molecules from natural sources have demonstrated anthelmintic activity against parasites. In this work, the monoterpenoids carvacrol, carvone, cineole, linalool, limonene, and thymol and the phenylpropanoids cinnamaldehyde, anethole, vanillin, and eugenol were assessed individually or in mixtures of ten binary, three ternary, and three quaternary combinations using the in vitro egg hatch assay with eggs of a multi-drug resistant strain of Haemonchus contortus. The main objective of this study was to identify the most effective interaction among essential oils with the greatest individual anthelmintic efficacy and to determine the most powerful combinations. The essential oils were ranked by their 50% lethal concentration (LC50) as follows (mg/mL): cinamaldehyde (0.018), anethole (0.070), carvone (0.085), carvacrol (0.11), thymol (0.13), linalool (0.29), vanillin (0.57), eugenol (0.57), cineole (4.74), and limonene (207.5). Quantification of synergism, additive effect, and antagonism were calculated for binary, ternary, and quaternary combinations. The best anthelmintic effect resulting from synergistic activity among 16 different combinations was for cinnamaldehyde:carvacrol (CL50 0.012mg/mL) and anethole:carvone (CL50 0.013mg/mL). These results indicate that these binary combinations would be promising to be tested in sheep infected with H. contortus.


Asunto(s)
Antihelmínticos/farmacología , Hemoncosis/veterinaria , Haemonchus/efectos de los fármacos , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Enfermedades de las Ovejas/tratamiento farmacológico , Animales , Sinergismo Farmacológico , Hemoncosis/tratamiento farmacológico , Hemoncosis/parasitología , Monoterpenos/farmacología , Ovinos , Enfermedades de las Ovejas/parasitología
16.
Med Mycol Case Rep ; 17: 14-16, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28626627

RESUMEN

Histoplasmosis is a systemic mycosis caused by Histoplasma capsulatum. Rare in Europe but endemic in some regions of Brazil, United States, Africa and Asia. Most of the cases are asymptomatic. Disseminated form is defined by the presence of an extra-pulmonary focus, particularly associated with immunosuppression. We report a case of an unilateral persisted tonsillar ulceration, in an immunocompetent Portuguese host, as manifestation of disseminated African histoplasmosis 45 years later after living 3 years in Africa.

17.
Eur J Clin Microbiol Infect Dis ; 36(7): 1345-1352, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28188492

RESUMEN

There is a lack of knowledge on the epidemiology of fungal infections worldwide because there are no reporting obligations. The aim of this study was to estimate the burden of fungal disease in Portugal as part of a global fungal burden project. Most published epidemiology papers reporting fungal infection rates from Portugal were identified. Where no data existed, specific populations at risk and fungal infection frequencies in those populations were used in order to estimate national incidence or prevalence, depending on the condition. An estimated 1,510,391 persons develop a skin or nail fungal infection each year. The second most common fungal infection in Portugal is recurrent vulvovaginal candidiasis, with an estimated 150,700 women (15-50 years of age) suffering from it every year. In human immunodeficiency virus (HIV)-infected people, oral or oesophageal candidiasis rates were estimated to be 19.5 and 16.8/100,000, respectively. Candidaemia affects 2.19/100,000 patients, in a total of 231 cases nationally. Invasive aspergillosis is less common than in other countries as chronic obstructive pulmonary disease (COPD) is uncommon in Portugal, a total of 240 cases annually. The estimated prevalence of chronic pulmonary aspergillosis after tuberculosis (TB) is 194 cases, whereas its prevalence for all underlying pulmonary conditions was 776 patients. Asthma is common (10% in adults) and we estimate 16,614 and 12,600 people with severe asthma with fungal sensitisation and allergic bronchopulmonary aspergillosis, respectively. Sixty-five patients develop Pneumocystis pneumonia in acquired immune deficiency syndrome (AIDS) and 13 develop cryptococcosis. Overall, we estimate a total number of 1,695,514 fungal infections starting each year in Portugal.


Asunto(s)
Micosis/epidemiología , Micosis/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Portugal/epidemiología , Prevalencia , Adulto Joven
18.
Oper Dent ; 41(5): 491-500, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26794188

RESUMEN

OBJECTIVE: The aim of this study was to investigate the effect of delayed photo-activation on elastic modulus, Knoop hardness, and post-gel shrinkage of dual cure resin cements and how this affects residual shrinkage stresses in posterior teeth restored with ceramic inlays. METHODS AND MATERIALS: Four self-adhesive (RelyX Unicem, 3M ESPE; GCem, GC; MonoCem, Shofu; and seT, SDI) and two conventional (RelyX ARC, 3M ESPE; and AllCem, FGM) dual cure resin cements for cementing posterior ceramic inlays were tested. Strain gauge and indentation tests were used to measure the post-gel shrinkage (Shr), elastic modulus (E), and Knoop hardness (KHN) when photo-activated immediately and 3 and 5 minutes after placement (n=10). Shr, E, and KHN results were analyzed using two-way analysis of variance followed by Tukey honestly significant difference post hoc tests (α=0.05). The experimentally determined properties were applied in a finite element analysis of a leucite ceramic inlay (Empress CAD, Ivoclar Vivadent) cemented in a premolar. Modified von Mises stresses were evaluated at the occlusal margins and cavity floor. RESULTS: Shr, E, and KHN varied significantly among the resin cements (p<0.001). Highest overall Shr values were found for RelyX Unicem; GCem had the lowest. Increasing the photo-activation delay decreased Shr significantly. Delayed photo-activation had no effect on E (p=0.556) or KHN (p=0.927). RelyX Unicem had the highest E values; seT and MonoCem had the lowest E values. AllCem and RelyX Unicem had the highest KHN and MonoCem had the lowest KHN. Cements with high Shr and E values caused higher shrinkage stresses. Stresses decreased with delayed photo-activation for all cements. CONCLUSIONS: KHN and E values varied among the different resin cements. Residual shrinkage stress levels decreased with increasing photo-activation delay with all resin cements.

19.
J Dent ; 43(12): 1519-28, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26449641

RESUMEN

OBJECTIVES: To compare bulk-fill with incremental filling techniques for restoring large mesio-occlusal-distal (MOD) restorations. METHODS: Seventy-five molars with MOD preparations were divided into five groups: Z350XT, incrementally filled with Filtek Z350XT and four bulk-fills-FBF/Z350XT, Filtek Bulk Fill/Filtek Z350XT; VBF/CHA, Venus Bulk Fill/Charisma Diamond; SDR/EST-X, SDR/Esthet-X HD; TEC, TetricEvoCeram Bulk Fill. Cuspal strains were measured using strain-gauges (n=10): CSt-Re, during restorative procedure; CSt-100N, during 100N occlusal loading; CSt-Fr, at fracture load. Before fracture load, teeth were load-cycled. Fracture resistance, fracture mode, and enamel cracks were recorded. The other five teeth were used for Elastic modulus (E) and Vickers hardness (VH). Post-gel shrinkage (Shr), diametral tensile strength (DTS) and compressive strength (CS) were determined (n=10). Shrinkage stresses were analyzed using finite element analysis. RESULTS: SDR had similar CS values as TEC, lower than all other composites. CHA had similar DTS values as Z350XT, higher than all other composites. Z350XT had the highest mean Shr and SDR the lowest Shr. New enamel cracks and propagation was observed after the restoration, regardless of filling technique. Z350XT had lower fracture resistance than bulk-fill composite techniques. No significant differences in failure modes were found. E and VH were constant through the depth for all techniques. Bulk-filling techniques had lower stresses compared to Z350XT. CONCLUSIONS: Flowable bulk-fill composites had lower mechanical properties than paste bulk-fill and conventional composites. All bulk-fill composites had lower post-gel shrinkage than conventional composite. Bulk-fill filling techniques resulted in lower cusp strain, shrinkage stress and higher fracture resistance. CLINICAL SIGNIFICANCE: Using bulk-fill composites cause lower CSt wich indicates lower stress in restored tooth. Furthermore, bulk-fill composites have a higher fracture resistance. Therefore, clinicians may choose the bulk-fill composite to decrease undesirable effects of restoration while simplifying filling procedure.


Asunto(s)
Resinas Compuestas/química , Restauración Dental Permanente/métodos , Análisis del Estrés Dental , Preparación de la Cavidad Dental/métodos , Esmalte Dental/fisiopatología , Materiales Dentales/química , Análisis de Elementos Finitos , Humanos , Metacrilatos/química , Diente Molar , Estrés Mecánico
20.
J Oral Rehabil ; 41(2): 108-14, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24666269

RESUMEN

The aim of this study was to investigate the biomechanical behaviour of maxillary premolar teeth regarding root morphology and abfraction depth, submitted to axial and oblique occlusal load. The investigation was conducted using 3D finite element analysis and strain gauge test. Sound maxillary premolar single and double root were selected for 3D model generation. The teeth were scanned for external morphology data acquisition. The 3D geometry was stored in *.STL and exported to Bio-CAD software (Rhinoceros-3D) to model generation. Mesh generation, mechanical properties and boundary conditions were performed in finite element software (Femap, Noran Engineering, USA). Twelve models were generated: sound tooth, 1.25 and 2.5 mm abfraction teeth. 100N compressive static load was applied: axially and 45° angle to the long axis on the palatine surface of the buccal cusp. Two strain gauges were bonded on the teeth mounted in a mechanical testing machine. Von Mises criterion showed that the double-root teeth associated with 2.5 mm abfraction and oblique loading presented higher stress values. Axial loading associated with single-root teeth propitiated the lowest stress rates. Double root sound 1.25 and 2.5 mm abfraction teeth associated with oblique loading showed the highest strain values (µS): 692.6, 1043.31 and 1236.14, respectively. Single root sound 1.25 and 2.5 mm abfraction teeth associated with oblique loading showed 467.10, 401.51 and 420.98 strain values, respectively. Axial loading showed lower strain rates, ranging from 136.12 to 366.91. The association of deep lesions, oblique loading and double-root tooth promoted higher stress and strain concentration.


Asunto(s)
Diente Premolar/fisiopatología , Fuerza de la Mordida , Análisis del Estrés Dental/métodos , Estrés Mecánico , Raíz del Diente/fisiopatología , Fenómenos Biomecánicos , Análisis de Elementos Finitos , Humanos , Imagenología Tridimensional , Maxilar
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