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1.
Community Dent Health ; 40(1): 30-36, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36696469

RESUMEN

BACKGROUND: The Black population has poorer oral health than other racial groups; however, little is known about the mechanisms that explain this difference. OBJECTIVE: To study the association between race and tooth loss and map the evidence on factors associated with tooth loss in Black older populations. METHODS: Scoping review following the PRISMA Extension for Scoping Reviews conducted according to the recommendations of the Joanna Briggs Institute. A three-step search strategy was applied, and data were collected between April and July 2021. Searches were performed in the PubMed, Lilacs, and SciELO databases. The grey literature was searched using Google Scholar (https://www.scholar.google.com/). The reference lists of included studies were used as additional sources. Studies published in English and Portuguese of the association between tooth loss and different racial groups and the factors associated with tooth loss and tooth retention in Black older adult populations were included. RESULTS: Twenty-one of 913 original articles published between 1995 and 2020 were included. Of these, 75% were research articles, 15% were reports, and 10% dissertations. Eighty per cent reported cross-sectional and 20% longitudinal data. African ancestry was associated with increased odds of tooth loss in older adult populations. Periodontal disease, female sex, and advanced age were the exposures most frequently associated with tooth loss. CONCLUSION: Race, educational level, advanced age, and oral diseases such as periodontitis are associated with increased tooth loss in Afro-descendant older populations.


Asunto(s)
Enfermedades Periodontales , Periodontitis , Pérdida de Diente , Anciano , Femenino , Humanos , Estudios Transversales , Etnicidad , Pérdida de Diente/epidemiología
2.
Trop Anim Health Prod ; 55(5): 314, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37736780

RESUMEN

Although it is considered an economically relevant and prevalent disease, little information is available on the epidemiology and risk factors of porcine proliferative enteropathy (PPE) in commercial pigs, and no publication is available on subsistence pig farming. The objectives of this study were to estimate the seroprevalence of L. intracellularis and identify associated risk factors in backyard pigs in the 12 mesoregions of the state of Minas Gerais, Brazil. Blood from pigs between 2 months and 6 years of age were sampled; an epidemiological questionnaire was applied to 288 properties investigated in 2016. Serum samples were tested for the presence of anti-L. intracellularis antibodies using an immunoperoxidase monolayer assay. The seroprevalence of L. intracellularis was 97.7% (CI 95%: 96.7-98.4), and there was no statistical difference among the prevalence of the sampled mesoregions. Only 3 of the 12 risk factors were significant when samples were analyzed from strongly seropositive animals (≥ 1:120) in a Poisson multivariate regression model. There was an interaction between properties in peri-urban areas and extensive production systems. This interaction demonstrated an increase in prevalence rates by 3.7 times (95%CI: 2.4-5.8). Properties close to dumps demonstrated an increase in prevalence rates by 2.2 times (95%CI: 0.99-4.8). In conclusion, anti-L. intracellularis antibodies were widely dispersed in subsistence pig farming's in Minas Gerais, indicating a wide circulation of the agent in this type of production system. The interactions of animals raised close to peri-urban areas, extensively, and close to landfills are risk factors for spread of PPE.


Asunto(s)
Lawsonia (Bacteria) , Animales , Porcinos , Brasil/epidemiología , Estudios Seroepidemiológicos , Agricultura , Factores de Riesgo
3.
Trop Anim Health Prod ; 50(7): 1493-1497, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29656341

RESUMEN

The main objective of this research was to conduct an exploratory study of the lactation curve in order to characterize the productive potential of Pantaneiro ewes and lambs. Fifty ewes were bred using four rams in two different mating seasons. The ewes were kept with their lambs on pasture of Brachiaria brizantha. Ewe body score, ewe weight, and lamb weight were evaluated. Milk sampling was performed every week. In the morning for milk collections, the ewes were treated with 1 UI of oxytocin (intramuscular) for complete milking. Lambs were separated from the ewes for 4 h and milk collections were performed. The total milk production over 24 h was estimated by multiplying the production of this period (4 h) by 6. The data were analyzed using the MIXED procedure (P < 0.05) in SAS. Milk production data were fitted to the curve using the incomplete gamma function of Wood, and lamb growth data were fitted using the Gompertiz equation. The average milk production of the ewes was 1.03 kg/day-1. Younger ewes had the lowest milk production (18 = 798 ± 330, 24 = 1001 ± 440, 36 = 1100 ± 490, and 48 = 1106 ± 490 g/day-1). Ewe body score at lambing affected initial milk production (1.0 = 816 ± 660, 1.5 = 1089 ± 105, and 2.0 = 1424 ± 1600 g/day-1). Lambs were weaned with an average weight of 20.3 kg. Daily weight gain from birth to weaning was 181 g. Locally adapted Pantaneiro ewes showed a linear decreasing lactation curve, with reduced production from the second week of lactation. Overall, evaluation of the dairy production and lamb performance revealed great variation, denoting potential for selection.


Asunto(s)
Cruzamiento , Lactancia/fisiología , Oveja Doméstica/fisiología , Destete , Aumento de Peso , Alimentación Animal , Animales , Peso Corporal , Ambiente , Femenino , Modelos Lineales , Masculino , Leche , Parto , Hojas de la Planta , Embarazo , Reproducción , Estaciones del Año , Ovinos
4.
Epidemiol Infect ; 143(11): 2446-50, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25483025

RESUMEN

Rickettsia rickettsii infection is being increasingly recognized as an important cause of fatal acute illness in Brazil, where this tick-borne disease is designated Brazilian spotted fever (BSF). In this study we report five fatal cases of BSF in employees of an animal shelter in an urban area in the municipality of Rio de Janeiro in southeast Brazil after a natural disaster on 11 January 2011. Four of the cases occurred from 27 January to 11 April 2011, while the fifth fatal case was identified in April 2012. Three cases were confirmed by molecular analysis and two by epidemiological linkage. An investigation of BSF was performed in the animal shelter, and blood samples were collected from 115 employees and 117 randomly selected dogs. The presence of high levels (1024-4096) of antibodies against spotted fever group rickettsiae was found in three (2·6%) employees and 114 (97·5%) dogs. These findings emphasize the need to consider BSF as a possible cause of undifferentiated febrile illness, especially dengue and leptospirosis, in patients occupationally exposed to dogs heavily infested by ticks, mainly working at kennels and animal shelters that have inadequate space for the animals housed and frequently providing an environment conducive to exposure to pathogens such as R. rickettsii.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Enfermedades de los Perros/diagnóstico , Vivienda para Animales , Enfermedades Profesionales/diagnóstico , Rickettsia rickettsii/inmunología , Fiebre Maculosa de las Montañas Rocosas/veterinaria , Garrapatas , Adulto , Animales , Brasil , Dengue/diagnóstico , Diagnóstico Diferencial , Perros , Resultado Fatal , Femenino , Humanos , Leptospirosis/diagnóstico , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/inmunología , Fiebre Maculosa de las Montañas Rocosas/diagnóstico , Fiebre Maculosa de las Montañas Rocosas/inmunología , Población Urbana
5.
J Colloid Interface Sci ; 668: 25-36, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38669993

RESUMEN

In the realm of polymer composites, there is growing interest in the use of more than one filler for achieving multifunctional properties. In this work, a composite separator membrane has been developed for lithium-ion battery application, by incorporating conductive silver nanowires (AgNWs) and titanium dioxide (TiO2) nanoparticles into a poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) polymer matrix. The composite membranes were manufactured by solvent casting and thermally induced phase separation, with total filler content varying up to 10 wt%. The ternary composites composites present improved mechanical characteristics, ionic conductivity and lithium transfer number compared to the neat polymer matrix. On the other hand, the filler type and content within the composite has little bearing on the morphology, polymer phase, or thermal stability. Once applied as a separator in lithium-ion batteries, the highest discharge capacity value was obtained for the 5 wt% AgNWs/5 wt% TiO2/PVDF-HFP membrane at different C-rates, benefiting from the synergetic effect from both fillers. This work demonstrates that higher battery performance can be achieved for next-generation lithium-ion batteries by using separator membranes based on ternary composites.

6.
Braz J Med Biol Res ; 56: e12671, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36995875

RESUMEN

In biliary atresia (BA), efforts to prevent premature liver transplantation (LT) are aimed at early diagnosis, timing of Kasai-portoenterostomy (KPE), and centralization of care. This report presents the clinical picture, treatment strategies, and outcomes of BA patients with no previous treatment. A retrospective cohort study (Jan/2001 to Jan/2021) was conducted to evaluate the outcome of patients with BA referred to a single team. Study groups were: 1) Kasai-only group (K-only) n=9), 2) LT-only group (n=7), and 3) Kasai+LT group (K+LT) (n=23). Survival with native liver and overall survival were 22.9 and 94.8%, respectively, at 120 months of follow-up. There was no difference in age at KPE in the K-only group (46.8±21.8 days) vs K+LT (52.1±22 days), P=0.4. Ten (25.6%) patients were babies conceived through in vitro fertilization (IVF). Four IVF patients (40%) presented associated congenital heart disease vs 5 patients (17%) in the remaining group (P=0.14). Two of the IVF patients were premature (<37 weeks). Median maternal age at birth was 35 years (33 to 41 years). Excellent patient survival is expected for patients with BA with the available treatment strategies. IVF+BA was an unexpected prevalent association in this cohort, and further studies are required to better understand these findings.


Asunto(s)
Atresia Biliar , Nacimiento Prematuro , Lactante , Recién Nacido , Femenino , Humanos , Adulto , Atresia Biliar/cirugía , Atresia Biliar/complicaciones , Atresia Biliar/diagnóstico , Portoenterostomía Hepática/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento , Fertilización In Vitro
7.
J Nanosci Nanotechnol ; 12(8): 6845-9, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22962833

RESUMEN

Ni0.5Zn0.5FeO4 ferrite/polyvinylidene fluoride composite films were prepared by a solution method and melt processing. As nanoparticle dispersion and polymer electroactive phase content are some of the key factors for improving magnetoelectric coupling in the composites, the dispersion of ferrite nanoparticles in the polymeric matrix was studied by preparing samples by two alternative dispersion routes: ultrasound and citric acid nanoparticle surfactation. The nucleation of the electroactive beta-phase of the polymer was observed in composites produced by nanoparticle dispersion by ultrasound. This fact avoids the need of stretching composites at elevated temperature in order to obtain the electroactive phase and obtain magnetoelectric composites. By this method, nevertheless, large nanoparticle agglomerates are obtained. Nanoparticle dispersion is largely improved by citric acid surfactation of the nanoparticles. On the other hand, the beta-phase of the polymer is not nucleated due to the modification of the nanoparticle-polymer interaction due to the presence of the surfactant.

8.
J Nanosci Nanotechnol ; 12(8): 6804-10, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22962826

RESUMEN

Polymer based composites of a-PVDF doped with different NaY zeolite (Na53Al53Si139O384) content were investigated. A good dispersion of NaY zeolite within the polymer matrix is achieved. The introduction of NaY nanoparticles enhance the storage modulus and the dielectric constant at room temperature. The dielectric constant at room temperature increases up to the value of 500 for the 32 wt% composite, at 1 kHz. The increase of the dielectric constant is mainly attributed to interfacial polarization effects. For increasing zeolite content, the nanocomposite conductivity shows two conducting regimes separted by the so called breaking voltage, which is associated to an intrazeolite charge transport. Thermogravimetric results show that the introduction of zeolites affects the thermal degradation of the polymer for low zeolite contents and also indicate the presence of water that also plays an important role in the electrical response of the materials.

9.
J Colloid Interface Sci ; 611: 366-376, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34959010

RESUMEN

Natural polymers are a promising alternative for reducing the environmental impact of batteries. For this reason, it is still necessary to study their behavior and implement its use in these devices, especially in separator membranes. This work reports on new separator membranes based on silk fibroin (SF) and silk sericin (SS) prepared by salt leaching method. The effect of the different SS relative content on the physiochemical properties of the membranes and on the electrochemical performance of the corresponding batteries with lithium iron phosphate (LFP) as cathodes has been reported. It is observed that the increasing of SS content leads to a decrease of the overall crystallinity of the membranes. All SF/SS membranes presented a well-defined porosity above 75% with a uniform distribution of interconnected micropores. The electrolyte uptake and the ionic conductivity are dependent on the relative SS content. The addition of 10 wt% of SS into SF membranes, induce a high ionic conductivity of 4.09 mS.cm-1 and high lithium transference number (0.52), due to the improvement of the Li+ ions conduction paths within the blended structure. Charge/discharge tests performed in Lithium/C-LFP half-cells reveal a discharge capacity of 85 mAh.g-1 at 2C after 100 cycles for batteries with a SF/SS separator, containing a 10 wt% of SS, which suggests a stabilizing effect of Sericin on discharge capacity. Further, a 50% and 35% of capacity of retention and capacity fade, respectively, is observed. The presented SF/SS membrane show high electrochemical stability, being suitable for implementation in a next generation of sustainable battery systems. This could allow the SS valorization considering that 150,000 tons of SS are abandoned each year, reducing the contamination of environmental effluents.


Asunto(s)
Fibroínas , Sericinas , Suministros de Energía Eléctrica , Litio , Polímeros
10.
J Colloid Interface Sci ; 596: 158-172, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33839349

RESUMEN

In order to improve battery performance by tuning battery separator membranes, this work reports on porous poly(vinylidene fluoride-co-trifluoroethylene) - P(VDF-TrFE)- membranes with surface pillar microstructures. Separators with tailored pillar diameter, height and bulk thickness were fabricated by template patterning and computer simulations, allowing to evaluate the effect of the pillar microstructure characteristics on battery performance. It is shown that the different pillar microstructures of the separators affect the uptake value (150-325%), ionic conductivity value (0.8-1.6 mS·cm-1) and discharge capacity of the lithium ion batteries (LIB) when compared with the separator without pillars. The experimental charge-discharge behavior demonstrates that the pillar parameters affect battery performance and the best microstructure leading to 80 mAh·g-1 at 2C. Battery performance can be thus optimized by adjusting pillar diameter, height and bulk thickness of the separators keeping its volume constant, as demonstrated also by the simulation results. The parameter with most influence in battery performance is the bulk thickness of the separator, allowing to obtain a maximum discharge capacity value of 117.8 mAh·g-1 at 90C for a thickness of 0.01 mm. Thus, this work shows that the optimization of the pillar microstructure of the separator membranes allows increasing the capacity towards a new generation of high-performance LIBs.

11.
Animal ; 15(4): 100192, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33637442

RESUMEN

Correct pasture management associated with the adjustment of grazing intensity determines pasture persistence and the level of production per animal and per land area. The objective of this review was to examine the effect of grazing intensity in tropical pastures on the performance and productivity of beef cattle by a meta-analytical approach. The review followed a protocol developed and tested based on the PICOS strategy to formulate the guiding question: population (beef cattle), intervention (high grazing intensities), comparison (low grazing intensities), outcome (animal performance and productivity), and study design (experimental). Data were collected from papers published in the electronic databases of SCOPUS (Elsevier), Web of Science (Main collection), SpringerLink, Wiley Online Library, and Science Direct (Elsevier) by a single cross-reference search. The selected studies were considered relevant when they: (1) were primary research published in the format of a research article; (2) included grazing intensities as a management strategy; and (3) evaluated average daily gain (ADG, kg/animal per day), stocking rates (SR, animal unit (AU)/ha; AU = 450 kg), and weight gain per area (WGH, kg/ha). Thirteen manuscripts were selected due to their methodological strength for data extraction. The means under continuous stocking were 0.67 kg/animal per day for ADG, 518.12 kg/ha for WGH, and 4.19 AU/ha for SR. Under intermittent stocking, the means were 0.62 kg/animal per day for ADG, 980.18 kg/ha for WGH, and 5.10 AU/ha for SR. In tropical forages, the heights of 20 to 40 cm for pastures under continuous stocking and the defoliation intensities of 40 to 50% for those under intermittent stocking result in greater individual performance and animal productivity per land area.


Asunto(s)
Alimentación Animal , Poaceae , Alimentación Animal/análisis , Animales , Bovinos , Estaciones del Año , Aumento de Peso
12.
J Colloid Interface Sci ; 582(Pt A): 376-386, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32861042

RESUMEN

Electrospun poly(vinylidene fluoride) (PVDF) fiber membranes doped with different ionic liquids (ILs) and sharing the same anion were produced and their potential as separator membranes for battery applications was evaluated. Different types of ILs containing the same anion, bis(trifluoromethylsulfonyl)imide [TFSI]-, were used with IL concentrations ranging between 0 and 15 wt% The morphology, microstructure, thermal and electrical properties (ionic conductivity and electrochemical window) of the membranes were evaluated. The presence of ILs in the PVDF polymer matrix influences the fiber diameter and the content of the polar ß phase within the polymer, as well as the degree of crystallinity. The thermal stability of the membranes decreases with the incorporation of IL. Impedance spectroscopy tests show a maximum ionic conductivity of 2.8 mS.cm-1 for 15% of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Emim][TFSI]) at room temperature. The electrochemical stability of the samples ranges from 0.0 to 6.0 V. When evaluated as battery separator membranes in C-LiFePO4 half-cells, a maximum discharge capacity of 119 mAh.g-1 at C-rate was obtained for the PVDF membrane with 15% [Emim][TFSI], with a coulombic efficiency close to 100%. The results demonstrate that the produced electrospun membranes are suitable for applications as separators for lithium ion batteries (LIBs).

13.
Chemosphere ; 262: 128300, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33182084

RESUMEN

Metronidazole (MNZ) is a recalcitrant antibiotic with toxic and carcinogenic effects in aquatic environments. In this work, Fe5(PO4)4(OH)3·2H2O (giniite) particles were synthesised with three different alkaline cations (Li+, Na+ and K+) and used as Fenton catalysts for MNZ removal. It is shown that the addition of different cations during the hydrothermal synthesis process promote different morphologies from asterisk-like to flower-like and branches-like, maintaining the crystalline structure of pure giniite. The photo-Fenton activity of these particles was then evaluated through the degradation of MNZ under sunlight radiation for 9 h. The results indicate that the alkaline cation has a predominant role in the photo-Fenton efficiency, as demonstrated by the superior degradation efficiencies of Na@giniite particles (91.2% and 72.5% with giniite concentration of 0.2 g L-1 and 0.07 g L-1, respectively), related with its high surface area (10.7 m2 g-1). Thus, it is demonstrated the suitability of Na@giniite particles as Fenton catalyst for MNZ removal from water.


Asunto(s)
Antibacterianos/análisis , Compuestos Férricos/química , Peróxido de Hidrógeno/química , Hierro/química , Metronidazol/análisis , Contaminantes Químicos del Agua/análisis , Antibacterianos/efectos de la radiación , Catálisis , Metronidazol/efectos de la radiación , Oxidación-Reducción , Procesos Fotoquímicos , Porosidad , Luz Solar , Propiedades de Superficie , Contaminantes Químicos del Agua/efectos de la radiación
14.
J Hazard Mater ; 403: 123675, 2021 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-32846265

RESUMEN

The present work reports on the control of silk fibroin (SF) porous structures performance through various processing methods. The study includes the analysis of two dissolving techniques (CaCl2/H2O/EtOH ternary and LiBr/H2O binary solutions), three regeneration methods (gelation, lyophilization and gas foaming) and one post-processing (EtOH). In all the cases, followed steps lead to SF structures with porosity values above 94% and large surface areas. Also, results about samples microstructure, secondary organization, crystallinity and water behavior, reveal a direct correlation between processing and SF properties. Thanks to the achieved progress, the SF varying porous structures were evaluated for metalloids (As5+ and As3+) and heavy metals (Cr6+ and Cr3+) adsorption, observing a direct relationship between samples processing and ionic species adsorption ability. Thus, it is shown that the control of the properties of SF based porous structures through processing, represents a suitable and ecofriendly approach for the development of bio-based materials for environmental applications.


Asunto(s)
Fibroínas , Porosidad , Agua
15.
Benef Microbes ; 11(2): 175-181, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-31990221

RESUMEN

Studies aiming at the development and evaluation of alternative methods to minimise losses caused by the gastrointestinal nematode Haemonchus contortus are extremely important. Such research is essential, given the high morbidity rates among sheep and the significant mortality rates of lambs, allied to the low efficacy of commercial products for the control of this parasite. The purpose of this study was to evaluate the effect of the Saccharomyces cerevisiae (YT001 - YEASTECH) on the control of H. contortus and its modulation of the immune response in experimentally infected sheep. Eighteen sheep were divided into two groups. Group 1, the control group, comprised animals infected with H. contortus and supplemented with distilled water, while Group 2, the treated group, consisted of animals infected and supplemented with S. cerevisiae (400 million cfu/day of suspension for 49 days). The following parasitological parameters were evaluated: number of eggs per gram of faeces, number of infective larvae (L3) recovered per faecal culture, and parasitic load of the abomasum. The following immunological parameters were quantified: immunoglobulin (Ig)A in the mucous secretions and serum IgG; cytokines interleukin (IL)-4, IL-5 and IL-10; number of eosinophils in the abomasal mucosa and groups of cells positive for the markers: MHCII, CD4+CD25+, CD5+CD8+, WC4, CD5+CD4+, CD8+CD11b+ and CD5+WC1 by whole blood flow cytometry. The results revealed a significant decrease (P<0.05) in the number of larvae and significantly higher serum IgG levels (P<0.05) in the group supplemented with S. cerevisiae. The supplemented animals showed significantly larger numbers of eosinophils (P<0.05), as well as more cells positive for MHCII, CD4+CD25+, CD5+CD8+ than the control animals. This study confirmed the beneficial action of S. cerevisiae on the host immune response to H. contortus, as evidenced mainly by the smaller number of L3 recovered from the faeces of sheep supplemented with S. cerevisiae.


Asunto(s)
Suplementos Dietéticos/microbiología , Hemoncosis/veterinaria , Probióticos/administración & dosificación , Saccharomyces cerevisiae/inmunología , Enfermedades de las Ovejas/terapia , Ovinos/inmunología , Administración Oral , Animales , Anticuerpos Antihelmínticos/sangre , Citocinas/inmunología , Eosinófilos/inmunología , Heces/parasitología , Hemoncosis/inmunología , Hemoncosis/terapia , Haemonchus , Interacciones Microbiota-Huesped/inmunología , Inmunoglobulina A/análisis , Inmunoglobulina G/sangre , Recuento de Leucocitos , Masculino , Recuento de Huevos de Parásitos , Ovinos/parasitología , Enfermedades de las Ovejas/inmunología , Enfermedades de las Ovejas/parasitología
16.
RSC Adv ; 9(72): 42439-42449, 2019 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-35542870

RESUMEN

Silver vanadium oxide (SVO) and Silver Vanadium Oxide/Vanadium Oxide (SVO@VO) composite hydrogels are formed from the self-entanglement of ß-AgVO3 nanoribbons and slightly reduced vanadium oxide (VO) (VV 1.6VIV 0.4O4.8) nanoribbons; respectively. Starting from randomly distributed nanoribbons within hydrogels, and after a controlled drying process, a homogeneous xerogel system containing tuneable SVO : VO ratios from 1 : 0 to 1 : 1 can be obtained. The precise nanoribbons compositional control of these composite system can serve as a tool to tune the electrical properties of the xerogels, as it has been demonstrated in this work by impedance spectroscopy (IS) experiments. Indeed, depending on the composition and temperature conditions, composite xerogels can behave as electronic, protonic or high temperature ionic conductors. In addition, the electric and protonic conductivity of the composite xerogels can be enhanced (until a critical irreversible point), through the temperature triggered charge carrier creation. As concluded from thermogravimetry, IR, UV-Vis and EPR spectroscopy studies, besides the SVO : VO ratio, the thermal induced oxidation/reduction of V5+ to V4+, and thermally triggered release of strongly bonded water molecules at the nanoribbon surface are the two key variables that control the electric and ionic conduction processes within the SVO and composite SVO/VO xerogels.

17.
Inflamm Bowel Dis ; 14(3): 389-95, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17924556

RESUMEN

BACKGROUND: Several neurological disorders have been described in inflammatory bowel disease (IBD) patients, but their exact frequency is unknown. METHODS: We prospectively studied the prevalence of neurological disorders (especially peripheral neuropathy) in a group of 82 patients with Crohn's disease (CD, n = 31) or ulcerative colitis (UC, n = 51) from 2 Brazilian tertiary care university clinics and followed them through a period of at least 1 year. All patients were interviewed and had complete neurological evaluations. RESULTS: Large-fiber sensory or sensorimotor polyneuropathy (PN) was observed in 16.1% of the CD and 19.6% of the UC patients. PN was usually mild, predominantly symmetric, and distal with axonal involvement. One patient had demyelinating PN at the diagnosis of CD. Mild carpal tunnel syndrome was common in female UC patients. Sensory symptoms without electromyography abnormalities, suggestive of small-fiber neuropathy or subclinical myelopathy, affected 29% and 11.8%, respectively. After excluding other known etiological or contributory factors for PN, 13.4% of the IBD patients had otherwise unexplained large-fiber or small-fiber PN (7.3% with large-fiber SM PN). Nondebilitating headache was the most common neurological complaint. Three patients had ischemic strokes, 5 were epileptic, and 1 transient chorea. CONCLUSIONS: Neurological disorders, especially PN, are common in our Brazilian cohort of IBD patients. They are diverse, multifactorial, and more common in women. Despite the mild phenotype in most cases, attention should be given by the general practitioner and gastroenterologist since they are frequently undiagnosed. Further studies are necessary to confirm these findings in populations with different genetic and nutritional backgrounds.


Asunto(s)
Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades del Sistema Nervioso Periférico/epidemiología , Vigilancia de la Población , Adulto , Brasil/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso Periférico/etiología , Prevalencia , Estudios Prospectivos , Factores de Riesgo
18.
Acta Gastroenterol Belg ; 81(4): 525-527, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30645923

RESUMEN

BACKGROUND AND STUDY AIMS: Percutaneous endoscopic gastrostomy is the most common therapeutic procedure performed by the digestive endoscopists in the upper gastrointestinal tract. It aims to feed patients presenting denutrition and/or insufficient oral intake. Percutaneous endoscopic gastrostomy feasibility is about 95-100 % although in some cases it is impossible to achieve it, leading to ask for a surgical placement. Even though the feasibility of the surgical approach is excellent its complications are quite higher than percutaneous endoscopic placement, it requires general anesthesia and sometimes these patients could be non elligible for it due to their comorbidities (malnutrition, cardio-vascular diseases etc.). Another alternative technique is the percutaneous radiological gastrostomy but this procedure is rarely available in our country. PATIENTS AND METHODS: We described four cases in patients with previous failure of PEG, in which we used an hybrid approach between radiological and endoscopic techniques, allowing the placement of gastrostomy tube, without general anesthesia. RESULTS: This was successful in all patients and there was no complication related to the procedure. CONCLUSIONS: This technique offers an additionnal opportunity to avoid general anesthesia and surgical complications in patients with unfavorable conditions.


Asunto(s)
Endoscopía Gastrointestinal/efectos adversos , Nutrición Enteral/efectos adversos , Fluoroscopía , Gastrostomía/métodos , Gastrostomía/efectos adversos , Humanos , Resultado del Tratamiento
19.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;56: e12671, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1430017

RESUMEN

In biliary atresia (BA), efforts to prevent premature liver transplantation (LT) are aimed at early diagnosis, timing of Kasai-portoenterostomy (KPE), and centralization of care. This report presents the clinical picture, treatment strategies, and outcomes of BA patients with no previous treatment. A retrospective cohort study (Jan/2001 to Jan/2021) was conducted to evaluate the outcome of patients with BA referred to a single team. Study groups were: 1) Kasai-only group (K-only) n=9), 2) LT-only group (n=7), and 3) Kasai+LT group (K+LT) (n=23). Survival with native liver and overall survival were 22.9 and 94.8%, respectively, at 120 months of follow-up. There was no difference in age at KPE in the K-only group (46.8±21.8 days) vs K+LT (52.1±22 days), P=0.4. Ten (25.6%) patients were babies conceived through in vitro fertilization (IVF). Four IVF patients (40%) presented associated congenital heart disease vs 5 patients (17%) in the remaining group (P=0.14). Two of the IVF patients were premature (<37 weeks). Median maternal age at birth was 35 years (33 to 41 years). Excellent patient survival is expected for patients with BA with the available treatment strategies. IVF+BA was an unexpected prevalent association in this cohort, and further studies are required to better understand these findings.

20.
Artículo en Inglés | LILACS | ID: biblio-1354807

RESUMEN

ABSTRACT: The authors report the case of a veterinarian who acquired brucellosis infection by accidental exposure to Brucella abortus vaccine (BRUCEL-VET B19) while performing animal vaccination. Antibiotic prophylaxis with doxycycline and rifampin for six weeks was indicated, but rifampin was discontinued after 10 days due to gastrointestinal in-tolerance. Despite prophylaxis, the patient seroconverted after 30 days, but was asymptomatic and did not require additional antibiotic therapy. Post-exposure prophylaxis of Brucella is not free from side effects and asymptomatic seroconversion can occur despite prophylaxis. (AU)


RESUMO: Os autores relatam o caso de um veterinário que adquiriu infecção por brucelose por exposição acidental à vacina Brucellaabortus (BRUCEL-VET B19) durante a vacinação animal. A profilaxia antibiótica com doxiciclina e rifampici-na por seis semanas foi indicada, mas a rifampicina foi descontinuada após 10 dias devido à intolerância gastroin-testinal. A profilaxia pós-exposição de Brucella não está isenta de efeitos colaterais e a soroconversãoassintomática pode ocorrer apesar da profilaxia. (AU)


Asunto(s)
Humanos , Masculino , Adulto , Brucelosis , Exposición Profesional , Vacunación , Veterinarios , Profilaxis Posexposición , Antibacterianos
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