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1.
Biomimetics (Basel) ; 8(8)2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38132538

RESUMEN

Ceramic biocomposites based on bioactive tricalcium phosphate doped with metal ions are a strategy for obtaining good biomimetics for human bone composition. Manufacturing with PMMA porogen also induces bone-like porosity morphology. The poor strength of tricalcium phosphate can be overcomed by designing ceramic composites reinforced with tetragonal and cubic zirconia. In this work, five different bioceramic composites were manufactured without and with induced porosity and their physical, mechanical, microstructural, and biological properties were studied. With the addition of tetragonal and cubic zirconia, an improvement in strength of 22% and 55%, respectively, was obtained, corresponding to up to 20.7 MPa. PMMA was suitable for adding porosity, up to 30%, with interconnectivity while an excellent hOB cellular viability was achieved for all biocomposites.

3.
ACS Omega ; 8(22): 19874-19891, 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37305278

RESUMEN

The current methods applied to material screening for adsorption-based heat pumps are based on a fixed set of temperatures or their independent variation, providing a limited, insufficient, and unpractical evaluation of different adsorbents. This work proposes a novel strategy for the simultaneous optimization and material screening in the design of adsorption heat pumps by implementing a meta-heuristic approach, particle swarm optimization (PSO). The proposed framework can effectively evaluate variable and broad operation temperature intervals to search for viable zones of operation for multiple adsorbents at once. The criteria for selecting the adequate material were the maximum performance and the minimum heat supply cost, which were considered the objective functions of the PSO algorithm. First, the performance was assessed individually, followed by a single-objective approximation of the multi-objective problem. Next, a multi-objective approach was also adopted. With the results generated during the optimization, it was possible to find which adsorbents and temperature sets were the most suitable according to the main objective of the operation. The Fisher-Snedecor test was applied to expand the results obtained during PSO application and a feasible operating region built around the optima, enabling the arrangement of close-to-optima data into practical design and control tools. This approach allowed for a fast and intuitive evaluation of multiple design and operation variables.

4.
Exp Parasitol ; 199: 74-79, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30840851

RESUMEN

Paramphistomes are important parasites in veterinary medicine. There are few anthelmintic drugs available against them. The development of new drugs is urgently needed and this process can be accelerated through the development of rodent models for in vivo testing. Among the few paramphistomes that develop in rodents is the caecal fluke Zygocotyle lunata, a species with which several biological studies have been performed over several decades. Nevertheless, its use as a model for evaluation of anthelmintic drugs had not yet been evaluated. In the present study, we evaluated the efficacy of praziquantel (PZQ 300 mg/kg 5x), albendazole (ABZ 200 mg/kg 5x) and closantel (CLO 50 mg/kg single dose, 50 mg/kg 3x and 25 mg/kg 3x) for treatment of mice experimentally infected with Z. lunata. The animals were infected with 20 metacercariae of the parasite and were treated 30 days post-infection. Untreated groups were maintained as controls. Seven days after the treatments, the animals were euthanized for recovery and counting of parasites. We found that PZQ and ABZ, at the dosages and therapeutic schedule employed here, did not cause significant alterations in worm burden [worm counts 16.0 ±â€¯2.8 (13-19), 17.6 ±â€¯2.1 (14-19) and 16.2 ±â€¯1.9 (13-18) (p = 0.51) in PZQ, ALB and control, respectively]. CLO 50 mg/kg in a single dose caused significant reduction in the number of parasites [treated: 1.8 ±â€¯0.9 (1-3); control: 15.6 ±â€¯2.5 (12-19)], although it did not result in complete elimination of the parasites in any animal. Despite the fact that three doses of CLO 50 mg/kg or CLO 25 mg/kg caused complete elimination of the parasites in most surviving animals, there was significant host mortality. In general, results here obtained are concordant with those of studies performed on ruminant paramphistomes. Given that Z. lunata can be maintained in laboratory rodents, it is a suitable model for screening anthelmintic drugs against paramphistomes.


Asunto(s)
Albendazol/uso terapéutico , Antihelmínticos/uso terapéutico , Paramphistomatidae/efectos de los fármacos , Praziquantel/uso terapéutico , Salicilanilidas/uso terapéutico , Infecciones por Trematodos/tratamiento farmacológico , Albendazol/química , Albendazol/farmacología , Análisis de Varianza , Animales , Antihelmínticos/química , Antihelmínticos/farmacología , Heces/parasitología , Masculino , Ratones , Paramphistomatidae/clasificación , Paramphistomatidae/aislamiento & purificación , Praziquantel/química , Praziquantel/farmacología , Salicilanilidas/química , Salicilanilidas/farmacología , Infecciones por Trematodos/parasitología
5.
Parasitol Res ; 117(12): 3927-3934, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30353231

RESUMEN

Postharmostomum commutatum (Dietz, 1858), a parasite of the caeca of poultry, has been reported from many different parts of the world. Despite its importance, there are no molecular sequences available and its phylogenetic position is unknown in relation to other members of Brachylaimoidea, a group in which taxonomic confusion reigns. Here, morphological and molecular techniques were used to study digeneans from the caeca of free-range chickens found naturally infected in the municipality of Viçosa, state of Minas Gerais, Brazil, between August 2017 and May 2018. The specimens were identified as P. commutatum, with Postharmostomum gallinum Witenberg, 1923 herein considered a junior synonym. Sequences obtained for the 28S, ITS2, and cox-1 genes were compared with sequences available from other species of Brachylaimoidea. Phylogenetic analysis of the three markers indicates P. commutatum formed an isolated lineage from other brachylaimoids, supporting the distinct status of the genus. The topology of phylogenetic trees obtained suggests that the morphology-based classification of families of Brachylaimoidea is artificial and new rearrangements of some genera or creation of new families may be necessary. The sequences newly obtained here will be useful for testing the cosmopolitan distribution of P. commutatum.


Asunto(s)
Ciego/parasitología , Pollos/parasitología , Trematodos/clasificación , Trematodos/genética , Animales , Brasil , Ciclooxigenasa 1/genética , ADN de Helmintos/genética , ADN Intergénico/genética , Filogenia , Aves de Corral/parasitología , ARN Ribosómico 28S/genética
6.
Arq Neuropsiquiatr ; 76(1): 22-25, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29364390

RESUMEN

To describe anticoagulation characteristics in patients with cardiac complications from Chagas disease and compare participants with and without cardioembolic ischemic stroke (CIS). A retrospective cohort of patients with Chagas disease, using anticoagulation, conducted from January 2011 to December 2014. Forty-two patients with Chagas disease who were using anticoagulation were studied (age 62.9±12.4 years), 59.5% female and 47.6% with previous CIS, 78.6% with non-valvular atrial fibrillation and 69.7% with dilated cardiomyopathy. Warfarin was used in 78.6% of patients and dabigatran (at different times) in 38%. In the warfarin group, those with CIS had more medical appointments per person-years of follow-up (11.7 vs 7.9), a higher proportion of international normalized ratios within the therapeutic range (57% vs 42% medical appointments, p = 0.025) and an eight times higher frequency of minor bleeding (0.64 vs 0.07 medical appointments). Patients with Chagas disease and previous CIS had better control of INR with a higher frequency of minor bleeding.


Asunto(s)
Anticoagulantes/uso terapéutico , Isquemia Encefálica/prevención & control , Cardiomiopatía Chagásica/complicaciones , Embolia/prevención & control , Accidente Cerebrovascular/prevención & control , Anciano , Anticoagulantes/efectos adversos , Cardiomiopatía Chagásica/sangre , Dabigatrán/efectos adversos , Dabigatrán/uso terapéutico , Femenino , Estudios de Seguimiento , Hemorragia/inducido químicamente , Humanos , Relación Normalizada Internacional , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Warfarina/efectos adversos , Warfarina/uso terapéutico
7.
Arq. neuropsiquiatr ; 76(1): 22-25, Jan. 2018. tab
Artículo en Inglés | LILACS | ID: biblio-888342

RESUMEN

ABSTRACT Objectives To describe anticoagulation characteristics in patients with cardiac complications from Chagas disease and compare participants with and without cardioembolic ischemic stroke (CIS). Methods A retrospective cohort of patients with Chagas disease, using anticoagulation, conducted from January 2011 to December 2014. Results Forty-two patients with Chagas disease who were using anticoagulation were studied (age 62.9±12.4 years), 59.5% female and 47.6% with previous CIS, 78.6% with non-valvular atrial fibrillation and 69.7% with dilated cardiomyopathy. Warfarin was used in 78.6% of patients and dabigatran (at different times) in 38%. In the warfarin group, those with CIS had more medical appointments per person-years of follow-up (11.7 vs 7.9), a higher proportion of international normalized ratios within the therapeutic range (57% vs 42% medical appointments, p = 0.025) and an eight times higher frequency of minor bleeding (0.64 vs 0.07 medical appointments). Conclusion Patients with Chagas disease and previous CIS had better control of INR with a higher frequency of minor bleeding.


RESUMO Objetivos descrever as características da anticoagulação em pacientes com manifestações cardíacas da doença de Chagas (MCDC) e comparar os participantes com sem acidente vascular cerebral isquêmico cardioembólico (AVCIC). Resultados 42 pacientes com MCDC em anticoagulação foram estudados (62,9 ± 12,4 anos), 59,5% do sexo feminino e 47,6% com AVCIC prévio, 78,6% portadores de fibrilação atrial não valvar e 69,7% com cardiomiopatia dilatada. Varfarina foi utilizada em 78,6% dos pacientes e dabigatrana em 38% (em momentos diferentes). No grupo da varfarina, aqueles com AVCIC tiveram mais consultas médicas por pessoas-ano de seguimento (11,7 vs 7,9), maior taxa de RNI na faixa terapêutica (57% vs 42% consultas médicas, p = 0,025) e uma frequência oito vezes maior de sangramento menor (0,64 vs. 0,07 consultas médicas). Conclusão pacientes com MCDC e AVCIC prévio têm melhor controle de RNI com maior frequência de sangramento menor.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Isquemia Encefálica/prevención & control , Cardiomiopatía Chagásica/complicaciones , Accidente Cerebrovascular/prevención & control , Embolia/prevención & control , Anticoagulantes/uso terapéutico , Warfarina/efectos adversos , Warfarina/uso terapéutico , Cardiomiopatía Chagásica/sangre , Estudios Retrospectivos , Estudios de Seguimiento , Relación Normalizada Internacional , Dabigatrán/efectos adversos , Dabigatrán/uso terapéutico , Hemorragia/inducido químicamente , Anticoagulantes/efectos adversos
8.
Dalton Trans ; 43(39): 14586-95, 2014 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-25135421

RESUMEN

Two new trinuclear copper(ii) complexes without end-capping ligands, (Bu4N)2[Cu(dmso)2{Cu(dnopba)(dmso)}2] () and (Bu4N)2[Cu(dmso)2{Cu(dcopba)(dmso)}2] () [dnopba = 4,5-dinitro-ortho-phenylenebis(oxamate), dcopba = 4,5-dichloro-ortho-phenylenebis(oxamate), Bu4N(+) = tetra-n-butylammonium and dmso = dimethylsulfoxide], were synthesized and their structures were determined by single crystal X-ray diffraction. The crystal structures of and consist of two outer bis(oxamato)(dmso)cuprate(ii) units which act as bidentate ligands toward a trans-bis(dmso)copper(ii) inner entity leading to centrosymmetric tricopper(ii) complexes with copper-copper separations across the oxamate bridges of 5.1916(3) () and 5.1776(3) Å (). The peripheral copper(ii) ions in and are five-coordinate in somewhat distorted square pyramidal environments with a dmso molecule filling the apical position whereas the inner copper(ii) ion is six-coordinate in an elongated octahedral environment with two dmso molecules in the axial sites. The investigation of their magnetic properties in the temperature range 2.0-300 K shows the occurrence of a strong intramolecular antiferromagnetic coupling between the copper(ii) ions through the oxamate bridges [J1 = -296(1) () and -334(1) cm(-1) (), the Hamiltonian being defined as H = -J1(SCu2·SCu1 + SCu2·SCu1')], which leads to a low-lying spin doublet at low temperatures. Density functional theory calculations (DFT) have been used to substantiate these magnetic couplings and also to analyse the influence exerted on these interactions by the type of substituent at the 4,5-positions from the phenylene ring of the bis(oxamate) ligand.

9.
DST j. bras. doenças sex. transm ; 22(4): 222-224, 2010. ilus
Artículo en Portugués | LILACS | ID: lil-590974

RESUMEN

O tumor de Buschke-Löwenstein é uma variedade pouco frequente da infecção pelo HPV. O tumor possui comportamento invasivo, embora seja histologicamente benigno. Pode estar associado a condições de imunossupressão e a recorrência após o tratamento é frequente. Objetivo: descrever um caso de um portador de aids e demonstrar que a imunossupressão é fator contribuinte, e que a cirurgia é o tratamento mais eficaz. Métodos: descrição do caso clínico, com referências na literatura. Resultados: foi realizada a cirurgia com ressecção ampliada e evolução satisfatória no pós-operatório.Conclusão: a cirurgia é o tratamento recomendado pela maioria dos autores e a biópsia é procedimento indicado para excluir malignidade.


Buschke-Löwenstein tumor is an uncommon variety of HPV infection. Being histologically benign, the tumor has invasive behavior. It maybe associated with conditions of immunosupression, and recurrence after treatment is frequent. Objective: to describe a case in a patient with AIDS, to show that immunosupression is a contributing factor, and that surgery is the most effective treatment. Methods: a case description, with references in the literature. Results: extended resection surgery with satisfactory outcome in the postoperative period. Conclusion: surgery is the treatment recommended by most authors and biopsy is an indicative procedure to exclude malignancy.


Asunto(s)
Humanos , Masculino , Adulto , Condiloma Acuminado/terapia , Enfermedades de Transmisión Sexual , Síndrome de Inmunodeficiencia Adquirida , Tumor de Buschke-Lowenstein/cirugía , Biopsia
10.
Rev. bras. farmacogn ; 20(4): 484-488, ago.-set. 2010. tab
Artículo en Portugués | LILACS | ID: lil-557934

RESUMEN

A atividade antioxidante, avaliada pelo método DPPH (1,1-difenil-2-picrilidrazila), e o teor em compostos fenólicos totais do extrato bruto metanólico e frações das folhas da espécie Palicourea rigida Kunth, Rubiaceae, foram quantificadas neste trabalho. Apesar da baixa atividade apresentada pelo extrato bruto (500 ppm), a fração acetato de etila apresentou atividade moderada (192 ppm) e o maior teor de fenólicos totais dentre as frações ensaiadas. Assim, a fração acetato de etila foi submetida a procedimentos cromatográficos o que resultou no isolamento dos flavonoides quercetina 3-O-β-D-glicosídeo, quercetina 3-O-soforosídeo e isoraminetina 3-glicosídeo, cujas estruturas foram elucidadas por análise espectroscópica, incluindo RMN (1D e 2D) e comparação com os dados da literatura.


The antioxidant activity, evaluated by DPPH (1,1-difenil-2-picrilidrazila) method, and the determination of the total phenolic compounds of the crude methanolic extract and fractions of the Palicourea rigida Kunth, Rubiaceae, leaves were quantified in this work. Despite weak activity exhibited by crude extract (500 ppm), the fraction ethyl acetate showed moderate activity (192 ppm), and the largest value for the phenolic compounds among all the assayed fractions. Then, the ethyl acetate fraction was submitted to the chromatography procedures which led to the isolation of the flavonoid quercetin 3-O-D-glicoside, quercetin 3-O-sophoroside and isorhamnetin 3-glicoside, which had the structures elucidated by spectroscopy analysis, including RMN (1D and 2D) and comparison with literature data.

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