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1.
J Oral Pathol Med ; 46(9): 846-852, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28731540

RESUMO

BACKGROUND: Chronic periapical lesions (CPLs) are common lesions of the oral cavity and are the result of caries, tooth fracture, iatrogenic causes, or factors causing contamination and pulp necrosis. Inflammatory cells participate in the expansion of CPLs by releasing factors that stimulate or inhibit osteolytic activity. The objective of this study was to investigate the participation of RANKL, TNF-α, cathepsin K, IL-33, and OPG in the development of radicular cysts (RCs) and periapical granulomas (PGs). METHODS: Paraffin-embedded sections of 30 RCs and 22 PGs were submitted to immunohistochemistry. RESULTS: Immunoexpression of the proteins studied was observed in the epithelium and capsule of RCs, as well as in connective tissue of PGs. The expression of the osteoclastogenic factors studied differed significantly in RCs and PGs (P < .001), with lower expression of OPG in RCs. In PGs, the lowest expression was observed for cathepsin K. Comparison of the 2 lesions showed a similar participation of RANKL and IL33, while a significant difference was observed for OPG (P < .001), TNF-α (P = .002), and cathepsin K (P = .016). No association of the expression of the proteins with lesions size was observed. CONCLUSIONS: This study demonstrated the participation of RANKL, TNF-α, IL-33, cathepsin K, and OPG in the development of RCs and PGs, with emphasis on the highest immunoreactivity of cathepsin in RCs and TNF-α and OPG in PGs. OPG possibly determines the slower growth of PGs compared to RCs.


Assuntos
Osteogênese/imunologia , Granuloma Periapical/imunologia , Cisto Radicular/imunologia , Adulto , Feminino , Humanos , Masculino , Granuloma Periapical/patologia , Cisto Radicular/patologia
2.
Phys Rev Lett ; 107(13): 135004, 2011 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-22026864

RESUMO

New transport experiments on JET indicate that ion stiffness mitigation in the core of a rotating plasma, as described by Mantica et al. [Phys. Rev. Lett. 102, 175002 (2009)] results from the combined effect of high rotational shear and low magnetic shear. The observations have important implications for the understanding of improved ion core confinement in advanced tokamak scenarios. Simulations using quasilinear fluid and gyrofluid models show features of stiffness mitigation, while nonlinear gyrokinetic simulations do not. The JET experiments indicate that advanced tokamak scenarios in future devices will require sufficient rotational shear and the capability of q profile manipulation.

3.
J Exp Med ; 175(1): 9-14, 1992 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-1370533

RESUMO

Injection of adult mice with high doses of monomeric human gamma globulins (dHGG) has been previously shown to produce a state of peripheral tolerance in both B and T cells. To gain insight into the mechanism of induction and maintenance of adult tolerance in this model, we have analyzed the pattern of lymphokines produced by control and tolerant animals in response to the tolerogen. The data presented indicate that HGG-specific, interleukin 2 (IL-2)- and interferon gamma (IFN-gamma)-producing T cells (thus referred to as T helper type 1 [Th1] cells) are rendered unresponsive after in vivo administration of soluble HGG. In contrast, antigenic stimulation of T cells isolated from tolerant adult mice leads to increased production of IL-4 in vitro. In vivo challenge of dHGG-treated adult animals with hapten-coupled HGG (p-azophenylarsonate [ARS]-HGG) induced a significant ARS-specific antibody response, suggesting that tolerance induction in this model does not completely abrogate tolerogen-specific Th activity in vivo. In agreement with the in vitro data, hapten-specific antibody response of tolerant animals is characterized by a selective deficiency in the IFN-gamma-dependent IgG2a subclass. Injection of immunogenic forms of HGG into tolerant animals also produced an IL-4-dependent increase in total serum IgE levels, indicative of an increased activity of HGG-specific Th2 cells in these animals. The finding that tolerance induction differentially affects Th subpopulations suggests that crossregulation among lymphocyte subsets may play a role in the induction and/or maintenance of acquired tolerance in adults.


Assuntos
Subpopulações de Linfócitos T/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T/imunologia , gama-Globulinas/imunologia , Animais , Anticorpos/análise , Ensaio de Imunoadsorção Enzimática , Imunoglobulina E/análise , Interleucina-2/biossíntese , Interleucina-4/biossíntese , Cinética , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos A , Radioimunoensaio , Valores de Referência , gama-Globulinas/administração & dosagem
4.
J Nematol ; 42(1): 8-16, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22736831

RESUMO

Twenty seven essential oils, isolated from plants representing 11 families of Portuguese flora, were screened for their nematicidal activity against the pinewood nematode (PWN), Bursaphelenchus xylophilus. The essential oils were isolated by hydrodistillation and the volatiles by distillation-extraction, and both were analysed by GC and GC-MS. High nematicidal activity was achieved with essential oils from Chamaespartium tridentatum, Origanum vulgare, Satureja montana, Thymbra capitata, and Thymus caespititius. All of these essential oils had an estimated minimum inhibitory concentration ranging between 0.097 and 0.374 mg/ml and a lethal concentration necessary to kill 100% of the population (LC(100)) between 0.858 and 1.984 mg/ml. Good nematicidal activity was also obtained with the essential oil from Cymbopogon citratus. The dominant components of the effective oils were 1-octen-3-ol (9%), n-nonanal, and linalool (both 7%) in C. tridentatum, geranial (43%), neral (29%), and ß-myrcene (25%) in C. citratus, carvacrol (36% and 39%), γ-terpinene (24% and 40%), and p-cymene (14% and 7%) in O. vulgare and S. montana, respectively, and carvacrol (75% and 65%, respectively) in T. capitata and T. caespititius. The other essential oils obtained from Portuguese flora yielded weak or no activity. Five essential oils with nematicidal activity against PWN are reported for the first time.

5.
Braz J Biol ; 79(2): 257-262, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30088525

RESUMO

Increased oxygen consumption and activation of specific metabolic pathways during or after physical exercise lead to the formation of reactive oxygen and nitrogen species. An investigation was made into the effects of pequi oil supplementation in protecting liver cells against injury resulting from oxidative stress. The experiments involved 20 male adult Wistar rats ( Rattus norvegicus). The animals were divided into four experimental groups: Group 1: sedentary control group; Group 2: exercise control group; Group 3: supplemented sedentary group; and Group 4: supplemented exercise group. Supplementation consisted of pequi oil administered by oral gavage (400 mg). The animals of the exercised groups were subjected to 20 swimming sessions for 5 weeks (with progressive increase of 10 minutes until exhaustion). Samples were collected from the right hepatic lobe for histopathological analysis and determination of malondialdehyde levels. The histopathological analyses revealed that the animals of the exercised control group had moderate liver damage, while the animals of the supplemented exercised group had slight tissue damage, and the sedentary control and sedentary supplemented groups showed no tissue damage. The malondialdehyde levels showed higher and statistically significant in exercise control group when compared to the other evaluated groups (p<0.05). In conclusion the supplementation with pequi oil had a protective effect on liver cells against damage caused by oxygen free radicals during strenuous exercise, as demonstrated by the indicator of lipid peroxidation.


Assuntos
Antioxidantes/farmacologia , Ericales/química , Fígado/efeitos dos fármacos , Óleos de Plantas/farmacologia , Natação/fisiologia , Animais , Masculino , Ratos , Ratos Wistar
6.
J Hum Hypertens ; 20(7): 523-8, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16543905

RESUMO

Obstructive sleep apnea (OSA) causes secondary hypertension. However, the reasons why the prevalence of hypertension among OSA patients varies widely (35-70%) are not clear. We sought to investigate the phenotypic characteristics of patients with and without hypertension among OSA patients who were matched for disease severity. We studied 152 OSA patients (76 normotensive and 76 hypertensive) diagnosed by polysomnography. Detailed phenotypic characteristics, including laboratorial analysis, were determined in all patients. Univariate analysis followed by multiple logistic regression analysis was used to identify variables that were independently associated with hypertension. The apnea-hypopnea index in normotensive and hypertensive patients was similar (48+/-26 and 48+/-26 events/h, respectively) as well as minimum arterial oxygen saturation (76+/-10 and 75+/-10%, respectively) and total sleep time with oxyhaemoglobin saturation <90% (25+/-25 and 28+/-26%, respectively). Hypertensive patients were older (57+/-11 vs 47+/-12 years; P<0.001), had a higher body mass index (BMI; 34+/-7 vs 30+/-5 kg/m(2); P<0.001), had a higher frequency of women (37 vs 8%; P<0.001), had a higher incidence of diabetes (25 vs 6%; P=0.002) and a higher family history of hypertension (75 vs 42%; P=0.01) than did the normotensive patients. Multiple logistic regression analysis indicated that age (P=0.004), familial history of hypertension (P=0.004), BMI (P=0.04) and female sex (P=0.03) were the independent variables associated with hypertension. We concluded that increasing age and BMI, familial history of hypertension as well as female gender are phenotypic characteristics associated with hypertension among OSA patients with similar disease severity.


Assuntos
Hipertensão/patologia , Apneia Obstrutiva do Sono/patologia , Adulto , Fatores Etários , Idoso , Análise de Variância , Índice de Massa Corporal , Feminino , Humanos , Hipertensão/sangue , Hipertensão/complicações , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Polissonografia/métodos , Análise de Regressão , Apneia Obstrutiva do Sono/sangue , Apneia Obstrutiva do Sono/complicações
7.
Theriogenology ; 86(4): 934-939, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27118386

RESUMO

The objectives were to (1) evaluate the effectiveness of induction of luteolysis in superovulated (SOV) cows at two distinct time points after embryo flushing; and (2) compare the pattern of LH release after treatment with PGF in cows with single vs. multiple ovulations. In the first experiment, Holstein cows were SOV with 400 IU of FSH following standard procedures. Uterine flushing for embryo recovery was performed 7 days after artificial insemination (Day 0), and cows were randomly allocated into two groups to receive PGF (0.5-mg sodium cloprostenol, intramascular) either immediately after flushing (Day 7 group, N = 19) or 4 days later (Day 11 group, N = 20). Time of luteolysis was determined on the basis of plasma progesterone (P4) concentrations. There was no difference (P > 0.05) in plasma P4 before treatment between Day 7 and Day 11 groups. A decline in plasma P4 was observed 48 hours after PGF treatment in both the groups (P < 0.0001). In Day 11 cows, P4 continued to decrease thereafter, whereas Day 7 animals had no further reduction in plasma P4. Luteolysis (P4 < 1 ng/mL) occurred in all Day 11 cows. In the Day 7 group, however, luteolysis failure was observed for 11 of 19 cows (57.9%). In cows without luteolysis, plasma P4 increased after the initial PGF-induced decline. The second experiment compared luteolysis in (SOV, N = 6) vs. non-SOV (control, N = 8) cows. Both groups received a single PGF treatment on Day 11 after estrus, and luteolysis was monitored daily by ovarian ultrasonography and plasma P4 measurements. In addition, plasma LH was measured in blood samples taken every 20 minutes for 1 hour during five consecutive days after treatment. A similar percentage of reduction in P4 was observed in both groups 24 hours after treatment; however, SOV cows only reached plasma P4 values similar (P > 0.05) to controls 96 hours after treatment. There was no difference in initial LH values between SOV and controls (P > 0.05). The slower decrease in plasma P4 in the SOV group prevented an increase in LH for up to 96 hours after luteolysis induction, whereas LH values increased (P < 0.05) in controls 24 hours after treatment. In conclusion, (1) luteolysis may fail or be incomplete when PGF treatment is given on the day of uterine flushing (Day 7) in SOV cows; (2) induction of luteolysis 4 days later (Day 11) is effective, but the initial high-plasma P4 concentrations result in a slower slope of P4 decline to basal levels, and consequently, delayed increase in LH pulses.


Assuntos
Bovinos/fisiologia , Cloprostenol/farmacologia , Hormônio Luteinizante/sangue , Luteólise/efeitos dos fármacos , Progesterona/sangue , Superovulação/efeitos dos fármacos , Animais , Bovinos/sangue , Cloprostenol/administração & dosagem , Feminino , Hormônio Foliculoestimulante/farmacologia , Luteolíticos/administração & dosagem , Luteolíticos/farmacologia
8.
Transfus Apher Sci ; 32(2): 221-5, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15784457

RESUMO

Cobe Trima version 4 is an apheresis system designed for the collection of combinations of Red Blood Cells (RBC), Platelets (PLT) and plasma components from a single donor. The validation of this apheresis system for PLT components in our institution evidenced the LRS efficacy, as leucoreduction was attained on a 100% basis. However, there were some unexpected occurrences regarding the PLT content. Certain donations showed large disagreements between programmed and obtained yields, not being found clear reasons for those outcomes. Furthermore, the mean platelet volume (MPV) was relatively low when compared with other platelets components produced by other methodologies. An investigation was initiated in order to know whether these shortcomings were donor or process/instrument related. A link was established between the raw material (donor), the process/instrument and the final product, and a new tool was introduced by the study of the LRS chamber. The LRS chamber content was assessed and the PLT cellular indices and PLT aggregation states compared with those obtained from the respective donor and the final product from the same origin. The storage stability of the final products was also analyzed based on these same tests to investigate if the initial low MPV had any deleterious effect during the shelf life of the components. Twenty five plateletpheresis donors, three of them new ones, were randomly selected for this study. For the first time, the content of the LRS chamber was used as a quality tool for identification of the cause of unexpected yields. Large aggregates remained in the LRS chamber in certain donors who were prone to undergo spontaneous aggregation, making the platelet yields low and platelet MPV very small. Based on repeated failures and on this new quality parameter showing LRS chamber abnormality, two donors were temporarily deferred from the panel. While it was not possible to identify the causes, it is appropriate to raise the question whether these profiles were Trima version 4 specific or not. Hence, further investigation is needed for a better clarification. In short, the simultaneous analysis of products and LRS content provided useful information not only for the characterization of donor-related phenomena but also helped in the identification of potential shortcomings in the machine performance allowing for remedial action to be taken on evidence based data.


Assuntos
Doadores de Sangue , Plaquetas , Agregação Plaquetária , Plaquetoferese , Plaquetas/citologia , Humanos , Plaquetoferese/instrumentação , Plaquetoferese/métodos , Controle de Qualidade
9.
Phytochemistry ; 55(3): 241-6, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11142850

RESUMO

The compositions of the essential oils obtained from ten populations of Thymus caespititius grown on S. Jorge (Azores) were studied by GC and GC-MS. All the oils analysed were dominated by their monoterpene fraction (69-9%). The sesquiterpene fraction was rather small (4-17%) and consisted mainly of oxygen-containing compounds (3-13%). Enantiomeric ratio of sabinene and alpha-terpineol was investigated in the oils from some populations. (+)-Sabinene was detected with high enatiomeric purity (96 99%). Although ( +)-alpha terpineol was the predominant enantiomer, its purity varied considerably (66-97%). Cluster analysis of all identified components grouped the oils into four main clusters that corresponded with their major components: alpha-terpineol (43-68%), carvacrol (32-52%), thymol (44-58%) and sabinene (41%). The essential oil from Th. caespititius showed a clear chemical polymorphism, that was particularly evident among four populations growing along a 200 m distance at Pico Verde.


Assuntos
Lamiaceae/química , Óleos Voláteis/química , Cromatografia Gasosa-Espectrometria de Massas , Magnoliopsida/química , Países Baixos , Óleos Voláteis/classificação , Extratos Vegetais/química , Estereoisomerismo
10.
Phytochemistry ; 57(2): 245-50, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11382240

RESUMO

The essential oils isolated from leaves of ten and from unripe berries of eight populations of Laurus azorica (Seub.) Franco, collected on five islands of the Azorean archipelago, were analysed by GC and GC-MS. All oil samples were dominated by their monoterpene fraction (60-94%), alpha-pinene (15-37%) and 1,8-cineole (12-31%) being the main components of the leaf oils, while trans-beta-ocimene (27-45%) and alpha-pinene (12-22%) were the main components of the oils from the berries. The sesquiterpene fractions of the oils ranged from 3 to 17% and the main components were beta-caryophyllene (traces-8%) and beta-elemene (traces-3%) both in the leaf and berry oils. Some phenylpropanoid components were also present, in total amounting to 17%, trans-cinnamyl acetate (215% of the leaf oils) being the main component of this fraction. Cluster analysis of the enantiomeric composition of alpha- and beta-pinene in the oils from the leaves clearly showed two groups, one constituted by the two populations growing on the island S. Jorge, and the other constituted by the remaining populations.


Assuntos
Lauraceae/química , Óleos Voláteis/isolamento & purificação , Cromatografia Gasosa , Espectrometria de Massas , Óleos Voláteis/química
11.
Transfus Apher Sci ; 29(1): 13-6, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12877887

RESUMO

Platelets derived from platelet rich plasma, buffy coat and Apheresis technologies differ in terms of in vitro functional activity, aggregation states and storage characteristics, as measured by automated cell counters, and pH assessment. This may be related to either differences in the subpopulation of platelets and leucocytes recovered or the processing/storage induced cellular damage. Some types of methodologies, such as BC derived-PC, appear to have a higher rate of bacterial contamination.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Plaquetas , Preservação de Sangue/métodos , Plaquetoferese/métodos , Plaquetas/metabolismo , Plaquetas/microbiologia , Ácido Edético/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Leucócitos , Transfusão de Plaquetas , Fatores de Tempo
12.
J Endourol ; 14(9): 731-3, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11110566

RESUMO

PURPOSE: To describe an easily home-made diathermy probe for the performance of retrograde endopyelotomies using a small-caliber rigid ureteroscope. METHODS: The diathermy probe is easily built by putting a rigid guidewire through a 5F ureteral catheter, the distal tip being naked and slightly bent. The other end is linked to the electric generator. Among a total of 24 retrograde endopyelotomies performed to treat ureteropelvic junction obstruction in the last 7 years, five were done using this device. RESULTS: Surgery with the probe took an average of 30 minutes. There were no complications, and, as of today, all cases are successes. CONCLUSION: This device allows the performance of retrograde endopyelotomy using a small-caliber ureteroscope. Long-term results will presumably match the good results obtained using the larger-caliber ureteroscopes with the classic cold knife.


Assuntos
Eletrocoagulação/instrumentação , Obstrução Ureteral/cirurgia , Ureteroscópios , Ureteroscopia/métodos , Adolescente , Adulto , Desenho de Equipamento , Feminino , Humanos , Pelve Renal/cirurgia , Masculino , Pessoa de Meia-Idade , Ureter/cirurgia
13.
Rev Inst Med Trop Sao Paulo ; 34(3): 199-203, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1342070

RESUMO

In the São Paulo State, Brazil, where the Biomphalaria tenagophila is the intermediate host, the Ribeira Valley is an important endemic schistosomiasis mansoni area. During last eleven years there has been intense control measures focusing on schistosomiasis. The efforts have been concentrated in the municipalities of Pedro de Toledo and Itariri. We determined the susceptibility of B. tenagophila to sympatric strain of S. mansoni, both recently isolated from Itariri field. In 1988, this strain was isolated and maintained in the experimental model: Swiss mice--sympatric B. tenagophila. The second generation of the worm was evaluated. The snail were divided in the three groups of 60 snails each. One group was exposed to 1 miracidium and other to 10. The third group was the control. The mortality and the shedding of cercariae were checked during 78 days. After that, the positive snails were observed until they ceased to shed cercariae. The exposed molluscs showed mortality rates of 23% and 31% and infection indexes were of 8% and 60% to 1 and 10 miracidia respectively. The mortality was of 22% in the control group. The periods of shedding cercariae in the two groups were 82 and 104 days. We can conclude that B. tenagophila is an effective intermediate host to the sympatric strain of S. mansoni sympatric strain.


Assuntos
Biomphalaria/parasitologia , Vetores de Doenças , Schistosoma mansoni/patogenicidade , Animais , Brasil , Interações Hospedeiro-Parasita , Larva/anatomia & histologia , Larva/patogenicidade , Camundongos , Schistosoma mansoni/anatomia & histologia , Fatores de Tempo
14.
Braz. j. biol ; 79(2): 257-262, Apr.-June 2019. graf
Artigo em Inglês | LILACS | ID: biblio-989455

RESUMO

Abstract Increased oxygen consumption and activation of specific metabolic pathways during or after physical exercise lead to the formation of reactive oxygen and nitrogen species. An investigation was made into the effects of pequi oil supplementation in protecting liver cells against injury resulting from oxidative stress. The experiments involved 20 male adult Wistar rats ( Rattus norvegicus). The animals were divided into four experimental groups: Group 1: sedentary control group; Group 2: exercise control group; Group 3: supplemented sedentary group; and Group 4: supplemented exercise group. Supplementation consisted of pequi oil administered by oral gavage (400 mg). The animals of the exercised groups were subjected to 20 swimming sessions for 5 weeks (with progressive increase of 10 minutes until exhaustion). Samples were collected from the right hepatic lobe for histopathological analysis and determination of malondialdehyde levels. The histopathological analyses revealed that the animals of the exercised control group had moderate liver damage, while the animals of the supplemented exercised group had slight tissue damage, and the sedentary control and sedentary supplemented groups showed no tissue damage. The malondialdehyde levels showed higher and statistically significant in exercise control group when compared to the other evaluated groups (p<0.05). In conclusion the supplementation with pequi oil had a protective effect on liver cells against damage caused by oxygen free radicals during strenuous exercise, as demonstrated by the indicator of lipid peroxidation.


Resumo Aumento do consumo de oxigênio e ativação de vias metabólicas específicas durante ou após a atividade física conduz para formação de espécies reativas de oxigênio e nitrogênio. Uma investigação foi realizada sobre os efeitos da suplementação com óleo de pequi na proteção das células hepáticas contra lesões resultantes do estresse oxidativo. Na realização dos experimentos foram utilizados 20 ratos machos adultos da linhagem Wistar (Rattus novergicus ). Os animais foram divididos em quatro grupos experimentais: grupo 1: grupo sedentário controle; grupo 2: grupo treinado controle; grupo 3: grupo sedentário suplementado e grupo 4: grupo treinado suplementado. Na suplementação foi utilizado o óleo de pequi ministrado por gavagem oral (400 mg). Os animais dos grupos treinados foram submetidos a 20 sessões de natação por um período de 5 semanas (com aumento progressivo de 10 minutos até a exaustão). Foram retiradas amostras do lobo hepático direito para análises histopatológicas, e dosagem de malondialdeído. As análises histopatológicas revelaram que os animais do grupo treinado controle tiveram danos hepáticos moderados; já os animais do grupo treinado suplementado tiveram danos teciduais leves; os grupos sedentário controle e sedentário suplementado não apresentaram injúrias teciduais. Os níveis de malondialdeído mostraram-se maiores e estatisticamente significativos no grupo treinado controle quando comparados aos outros grupos avaliados (p<0,05). Podemos concluir que a suplementação com óleo de pequi teve efeito protetor nas células hepáticas contra os danos causados pelos radicais livres de oxigênio durante os exercícios exaustivos, conforme demonstrado pelo indicador de peroxidação lipídica.


Assuntos
Animais , Masculino , Ratos , Natação/fisiologia , Óleos de Plantas/farmacologia , Ericales/química , Fígado/efeitos dos fármacos , Antioxidantes/farmacologia , Ratos Wistar
15.
Acta Biomater ; 8(11): 4101-10, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22846590

RESUMO

Thrombus formation, due to thrombin generation, is a major problem affecting blood-contacting medical devices. This work aimed to develop a new strategy to improve the hemocompatibility of such devices by the immobilization of a naturally occurring thrombin inhibitor into a nanostructured surface. Boophilin, a direct thrombin inhibitor from the cattle tick Rhipicephalus microplus, was produced as a recombinant protein in Pichia pastoris. Boophilin was biotinylated and immobilized on biotin-terminated self-assembled monolayers (SAM) via neutravidin. In order to maintain its proteinase inhibitory capacity after surface immobilization, boophilin was biotinylated after the formation of a boophilin-thrombin complex to minimize the biotinylation of the residues involved in thrombin-boophilin interaction. The extent of boophilin biotinylation was determined using matrix-assisted laser desorption/ionization-time of flight/time of flight mass spectrometry. Boophilin immobilization and thrombin adsorption were quantified using quartz crystal microbalance with dissipation. Thrombin competitive adsorption from human serum was assessed using ¹²5I-thrombin. Thrombin inhibition and plasma clotting time were determined using spectrophotometric techniques. Boophilin-coated SAM were able to promote thrombin adsorption in a selective way, inhibiting most of its activity and delaying plasma coagulation in comparison with boophilin-free surfaces, demonstrating boophilin's potential to improve the hemocompatibility of biomaterials used in the production of blood-contacting devices.


Assuntos
Antitrombinas/farmacologia , Materiais Biocompatíveis/farmacologia , Bioengenharia , Teste de Materiais , Trombina/farmacologia , Adsorção/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Antitrombinas/química , Antitrombinas/isolamento & purificação , Biotinilação/efeitos dos fármacos , Coagulação Sanguínea/efeitos dos fármacos , Bovinos , Ativação Enzimática/efeitos dos fármacos , Humanos , Hidrólise/efeitos dos fármacos , Proteínas Imobilizadas/metabolismo , Dados de Sequência Molecular , Peso Molecular , Proteínas Recombinantes/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Propriedades de Superfície , Trombina/química
16.
Nat Prod Res ; 25(5): 526-41, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21391115

RESUMO

Salvia officinalis L. oils were isolated from the plant's commercial dried aerial parts, by hydrodistillation, with different distillation times. The essential oils were analysed by gas chromatography and gas chromatography-mass spectrometry. The antioxidant ability was measured using a free radical scavenging activity assay using 2,2-diphenyl-1-picrylhydrazyl (DPPH), a thiobarbituric acid reactive substances (TBARS) assay, a deoxyribose assay for the scavenging of hydroxyl radical, an assay for site-specific actions and a 5-lipoxygenase assay. Antibacterial activity was determined by the agar diffusion method. 1,8-Cineole, α-pinene and camphor were the dominant components of all the essential oils. The different hydrodistillation times did not affect the oil yield nor the relative amount of the oil components. The time of hydrodistillation influenced the antioxidant activity. With the DPPH method, the oils isolated for 2 and 3 h were stronger free radical scavengers, while with the TBARS method, the highest antioxidant values were obtained in the oils isolated for 30 min, 2 and 3 h. Hydroxyl radical scavenging and lipoxygenase activity assays showed the best results with oils isolated for 1 and 3 h. With the deoxyribose method, sage oils at concentrations <1000 mg L(-1) showed better activity than mannitol. The essential oil of S. officinalis showed very weak antimicrobial activity.


Assuntos
Anti-Infecciosos/metabolismo , Antioxidantes/metabolismo , Óleos Voláteis/química , Salvia officinalis/química , Anti-Infecciosos/química , Antioxidantes/química , Monoterpenos Bicíclicos , Cânfora/análise , Cicloexanóis/análise , Destilação , Eucaliptol , Cromatografia Gasosa-Espectrometria de Massas , Monoterpenos/análise , Óleos Voláteis/análise , Substâncias Reativas com Ácido Tiobarbitúrico , Fatores de Tempo
17.
Rev Sci Instrum ; 81(10): 10D529, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21033884

RESUMO

We present the first simultaneous measurements of the Thomson scattering and electron cyclotron emission radiometer diagnostics performed at TCABR tokamak with Alfvén wave heating. The Thomson scattering diagnostic is an upgraded version of the one previously installed at the ISTTOK tokamak, while the electron cyclotron emission radiometer employs a heterodyne sweeping radiometer. For purely Ohmic discharges, the electron temperature measurements from both diagnostics are in good agreement. Additional Alfvén wave heating does not affect the capability of the Thomson scattering diagnostic to measure the instantaneous electron temperature, whereas measurements from the electron cyclotron emission radiometer become underestimates of the actual temperature values.

19.
Braz J Med Biol Res ; 41(3): 215-22, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18575711

RESUMO

We investigated the relationship between sleep-disordered breathing (SDB) and Cheyne-Stokes respiration (CSR) while awake as well as mortality. Eighty-nine consecutive outpatients (29 females) with congestive heart failure (CHF; left ventricular ejection fraction, LVEF <45%) were prospectively evaluated. The presence of SDB and of CSR while awake before sleep onset was investigated by polysomnography. SDB prevalence was 81 and 56%, using apnea-hypopnea index cutoffs >5 and >15, respectively. CHF etiologies were similar according to the prevalence of SDB and sleep pattern. Males and females were similar in age, body mass index, and LVEF. Males presented more SDB (P = 0.01), higher apnea-hypopnea index (P = 0.04), more light sleep (stages 1 and 2; P < 0.05), and less deep sleep (P < 0.001) than females. During follow-up (25 +/- 10 months), 27% of the population died. Non-survivors had lower LVEF (P = 0.01), worse New York Heart Association (NYHA) functional classification (P = 0.03), and higher CSR while awake (P < 0.001) than survivors. As determined by Cox proportional model, NYHA class IV (RR = 3.95, 95%CI = 1.37-11.38, P = 0.011) and CSR while awake with a marginal significance (RR = 2.96, 95%CI = 0.94-9.33, P = 0.064) were associated with mortality. In conclusion, the prevalence of SDB and sleep pattern of patients with Chagas' disease were similar to that of patients with CHF due to other etiologies. Males presented more frequent and more severe SDB and worse sleep quality than females. The presence of CSR while awake, but not during sleep, may be associated with a poor prognosis in patients with CHF.


Assuntos
Cardiomiopatia Chagásica/mortalidade , Respiração de Cheyne-Stokes/mortalidade , Insuficiência Cardíaca/mortalidade , Síndromes da Apneia do Sono/mortalidade , Adolescente , Adulto , Idoso , Cardiomiopatia Chagásica/complicações , Respiração de Cheyne-Stokes/etiologia , Métodos Epidemiológicos , Feminino , Insuficiência Cardíaca/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Prognóstico , Síndromes da Apneia do Sono/etiologia
20.
Curr Pharm Des ; 14(29): 3120-40, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19075695

RESUMO

Thymbra capitata and Thymus species are commonly known in Portugal as thyme and they are currently used as culinary herbs, as well as for ornamental, aromatizing and traditional medicinal purposes. The present work reports on the state of the art on the information available on the taxonomy, ethnobotany, cell and molecular biology of the Portuguese representatives of these genera and on the chemotaxonomy and antibacterial, antifungal and antioxidant activities of their essential oils and other volatile-containing extracts.


Assuntos
Antifúngicos , Antioxidantes , Óleos Voláteis , Óleos de Plantas , Thymus (Planta) , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Classificação , Etnobotânica , Humanos , Lamiaceae/química , Lamiaceae/classificação , Lamiaceae/crescimento & desenvolvimento , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologia , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação , Óleos de Plantas/farmacologia , Portugal , Thymus (Planta)/química , Thymus (Planta)/crescimento & desenvolvimento
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