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1.
Braz J Med Biol Res ; 56: e12576, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377306

RESUMO

Type 2 diabetes mellitus (T2DM) is characterized by endothelial dysfunction that causes micro- and macrovascular complications. Low intensity therapeutic ultrasound (LITUS) may improve endothelial function, but its effects have not been investigated in these patients. The aim of our study was to compare the effects of pulsed (PUT) and continuous (CUT) waveforms of LITUS on the endothelium-dependent vasodilation of T2DM patients. The present randomized crossover trial had a sample of twenty-three patients (7 men) diagnosed with T2DM, 55.6 (±9.1) years old, with a body mass index of 28.6 (±3.3) kg/m2. All patients were randomized and submitted to different waveforms (Placebo, CUT, and PUT) of LITUS and the arterial endothelial function was evaluated. The LITUS of 1 MHz was applied in pulsed (PUT: 20% duty cycle, 0.08 W/cm2 SATA), continuous (CUT: 0.4 W/cm2 SPTA), and Placebo (equipment off) types of waves during 5 min on the brachial artery. Endothelial function was evaluated using the flow-mediated dilation (FMD) technique. PUT (mean difference 2.08%, 95% confidence interval 0.65 to 3.51) and CUT (mean difference 2.32%, 95% confidence interval 0.89 to 3.74) increased the %FMD compared to Placebo. In the effect size analysis, PUT (d=0.65) and CUT (d=0.65) waveforms presented moderate effects in the %FMD compared to Placebo. The vasodilator effect was similar in the different types of waves. Pulsed and continuous waveforms of LITUS of 1 MHz improved the arterial endothelial function in T2DM patients.


Assuntos
Diabetes Mellitus Tipo 2 , Terapia por Ultrassom , Masculino , Humanos , Vasodilatação , Terapia por Ultrassom/métodos , Endotélio Vascular , Vasodilatadores/farmacologia , Vasodilatadores/uso terapêutico , Artéria Braquial/diagnóstico por imagem
2.
Braz. j. med. biol. res ; 56: e12576, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1447685

RESUMO

Type 2 diabetes mellitus (T2DM) is characterized by endothelial dysfunction that causes micro- and macrovascular complications. Low intensity therapeutic ultrasound (LITUS) may improve endothelial function, but its effects have not been investigated in these patients. The aim of our study was to compare the effects of pulsed (PUT) and continuous (CUT) waveforms of LITUS on the endothelium-dependent vasodilation of T2DM patients. The present randomized crossover trial had a sample of twenty-three patients (7 men) diagnosed with T2DM, 55.6 (±9.1) years old, with a body mass index of 28.6 (±3.3) kg/m2. All patients were randomized and submitted to different waveforms (Placebo, CUT, and PUT) of LITUS and the arterial endothelial function was evaluated. The LITUS of 1 MHz was applied in pulsed (PUT: 20% duty cycle, 0.08 W/cm2 SATA), continuous (CUT: 0.4 W/cm2 SPTA), and Placebo (equipment off) types of waves during 5 min on the brachial artery. Endothelial function was evaluated using the flow-mediated dilation (FMD) technique. PUT (mean difference 2.08%, 95% confidence interval 0.65 to 3.51) and CUT (mean difference 2.32%, 95% confidence interval 0.89 to 3.74) increased the %FMD compared to Placebo. In the effect size analysis, PUT (d=0.65) and CUT (d=0.65) waveforms presented moderate effects in the %FMD compared to Placebo. The vasodilator effect was similar in the different types of waves. Pulsed and continuous waveforms of LITUS of 1 MHz improved the arterial endothelial function in T2DM patients.

3.
Neotrop Entomol ; 48(6): 919-926, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31701476

RESUMO

Sugarcane is one of the most economically important crops in Brazil. The damage caused by Diatraea saccharalis (F.) (Lepidoptera: Crambidae) results in high costs for its production. Cotesia flavipes Cameron (Hymenoptera: Braconidae) is the most efficient means of controlling this pest. The prohibition of burning and the preservation of soil cover through non-tillage practices increased many population densities of natural enemies of the sugarcane borer (SCB) in sugarcane fields. Euborellia annulipes (Lucas) (Dermaptera: Anisolabididae) is a predator found in sugarcane fields and is associated with predation of SCB. This study aimed to evaluate the influence of parasitism of D. saccharalis by C. flavipes on predation by E. annulipes adult females. For this purpose, fourth instar sugarcane borer larvae were exposed to parasitism over a 5-day period or were not parasitized. Subsequently, the prey was supplied to the predator in arenas under choice and no-choice conditions and under different densities to evaluate the feeding preference over a 12-h period and functional response of the predator over a 24-h period. E. annulipes killed 2-3 fourth instar larvae of the sugarcane borer over a 12-h period. SCB parasitism did not affect the feeding preference of the predator and did not alter the type II functional response. However, the handling time of the predator was lower (1.943 h) and there was a higher T/Th ratio on the non-parasitized larvae (12.352). Our findings indicate E. annulipes as a promising biological control agent of D. saccharalis, with a potential to assist in the sugarcane borer management approaches and could to reduce the costs of parasitoid release in the field.


Assuntos
Himenópteros/fisiologia , Mariposas/parasitologia , Controle Biológico de Vetores , Saccharum , Animais , Brasil , Feminino , Larva/parasitologia
4.
Chemosphere ; 111: 623-30, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24997974

RESUMO

The immobilization of enzymes onto transducer support is a mature technology and has been successfully implemented to improve biocatalytic processes for diverse applications. However, there exists still need to design more sophisticated and specialized strategies to enhance the functional properties of the biosensors. In this work, a biosensor platform based on innovative fabrication strategy was designed, and employed for the detection of organophosphate (OP) in natural waters. The biosensor was prepared by incorporating acetylcholinesterase enzyme (AChE) to the graphite paste modified with tetracyanoquinodimethane (TCNQ) mediator, along with the use of a macroalgae (Cladaphropsis membranous) as a functional immobilization support. The novel immobilization design resulted in a synergic effect, and led to enhanced stability and sensitivity of the biosensor. The designed biosensor was used to analyze methyl parathion OP insecticide in water samples collected from a demonstrably contaminated lake of São Luis Island, Maranhão, Northeast of Brazil. Water analysis revealed that the aquatic ecosystem was polluted by sub-ppm concentrations of the OP insecticide, and a good correlation was found between values obtained through biosensor and GC-MS techniques. Our results demonstrated that macroalgae-biosensor could be used as a low-cost and sensitive screening method to detect target analyte.


Assuntos
Técnicas Biossensoriais/métodos , Inseticidas/análise , Metil Paration/análise , Alga Marinha/metabolismo , Poluentes Químicos da Água/análise , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Animais , Brasil , Electrophorus , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Grafite/química , Humanos , Inseticidas/metabolismo , Limite de Detecção , Metil Paration/metabolismo , Nitrilas/química , Alga Marinha/química , Poluentes Químicos da Água/metabolismo
5.
Med Intensiva ; 38(7): 444-54, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25060511

RESUMO

OBJECTIVE: To investigate the applications and effects of neuromuscular electrical stimulation (NMES) in critically ill patients in ICU by means of a systematic review. MATERIALS AND METHODS: Electronic searches were conducted in the databases Medline, CINAHL, Cochrane Central Register of Controlled Trials, Web of Science, Embase, ProQuest Health and Medical Complete, AMED, and PEDro. The PEDro score was used to assess the methodological quality of the eligible studies. RESULTS: The search yielded a total of 9759 titles and nine articles satisfied the eligibility criteria. These studies showed that NMES can maintain or increase muscle mass, strength and volume, reduce time in mechanical ventilation and weaning time, and increase muscle degradation in critically ill patients in ICU. Two studies allowed a meta-analysis of the effects of NMES on quadriceps femoris strength and it showed a significant effect in favor of NMES in the Medical Research Council (MRC) Scale (standardized mean difference 0.77 points; p=0.02; 95% CI: 0.13-1.40). CONCLUSIONS: The selected studies showed that NMES has good results when used for the maintenance of muscle mass and strength in critically ill patients in ICU. Future studies with high methodological quality should be conducted to provide more evidence for the use of NMES in an ICU setting.


Assuntos
Estado Terminal/terapia , Estimulação Elétrica , Humanos , Debilidade Muscular/terapia
6.
Scand J Med Sci Sports ; 23(5): 541-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22260485

RESUMO

The ankle is the joint most affected among the sports-related injuries. The current study investigated whether certain intrinsic factors could predict ankle sprains in active students. The 125 participants were submitted to a baseline assessment in a single session were then followed-up for 52 weeks regarding the occurrence of sprain. The baseline assessment were performed in both ankles and included the questionnaire Cumberland ankle instability tool - Portuguese, the foot lift test, dorsiflexion range of motion, Star Excursion Balance Test (SEBT), the side recognition task, body mass index, and history of previous sprain. Two groups were used for analysis: one with those who suffered an ankle sprain and the other with those who did not suffer an ankle sprain. After Cox regression analysis, participants with history of previous sprain were twice as likely to suffer subsequent sprains [hazard ratio (HR) 2.21 and 95% confidence interval (CI) 1.07-4.57] and people with better performance on the SEBT in the postero-lateral (PL) direction were less likely to suffer a sprain (HR 0.96 and 95% CI 0.92-0.99). History of previous sprain was the strongest predictive factor and a weak performance on SEBT PL was also considered a predictive factor for ankle sprains.


Assuntos
Traumatismos do Tornozelo/etiologia , Traumatismos em Atletas/etiologia , Instabilidade Articular/complicações , Entorses e Distensões/etiologia , Estudantes/estatística & dados numéricos , Índice de Massa Corporal , Brasil , Feminino , Humanos , Instabilidade Articular/fisiopatologia , Masculino , Modelos de Riscos Proporcionais , Estudos Prospectivos , Amplitude de Movimento Articular/fisiologia , Recidiva , Medição de Risco/métodos , Universidades , Adulto Jovem
7.
J Phys Condens Matter ; 22(6): 065702, 2010 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-21389373

RESUMO

Using the Kotliar and Ruckenstein slave boson formalism we consider the finite-U Anderson lattice. We study the appearance of superconductivity as a function of the Coulomb repulsion, density and f-level location for s-wave and d-wave pairing symmetries. The results extend previous studies where the infinite-U limit was considered, confirming that superconductivity remains as the Coulomb coupling increases, if the attractive interaction is not weak. Superconductivity disappears for large U as the filling of the heavy particles approaches one, as expected. Since U is finite, superconductivity occurs, in general, for any band-filling being depressed near half-filling, particularly for d-wave symmetry.

8.
Talanta ; 60(1): 115-21, 2003 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-18969031

RESUMO

The 2,4-dichlorophenoxyacetic acid (2,4-D) is one of the most applied herbicides around the world to control broad leave herbs in many crops. In this study, a method was developed for simultaneous extraction and determination of 2,4-D and its major transformation product, i.e., the 2,4-dichlorophenol (2,4-DCP), in soil samples. The herbicide and its degradation product were extracted twice from soil samples, after acidification, by dichloromethane on ultrasound system for 1 h. Both extracts were combined and filtrated in qualitative filter paper and Celite((R)). The total extract was concentrated in rotatory evaporator, dried under N(2) and finally dissolved in 1 ml of methanol. High Performance Liquid Chromatography with UV detection at 230 nm was used for analysis. Recoveries were obtained from soil samples fortified at 0.1, 1.0, 2.0, 3.0 and 4.0 mgkg(-1) levels and the results varied from 85 to 111% (for 2,4-D) and from 95 to 98% (for 2,4-DCP). For both compounds, the limits of quantification were 0.1 mgkg(-1), which were the loss level at which the accuracy and the precision were studied. Nevertheless, the limits of detection, calculated by considering the blank standard deviation and the minimum concentration level, were 0.03 and 0.02 mgkg(-1), for 2,4-D and 2,4-DCP, respectively. This proposed method was applied to soil samples of eucalyptus crops, which was previously treated with the herbicide. Despite that, neither 2,4-D nor its degradation product were detected 30 days after the herbicide application.

9.
J Chromatogr A ; 888(1-2): 113-20, 2000 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-10949478

RESUMO

An analytical method for the determination of aldicarb, and its two major metabolites, aldicarb sulfoxide and aldicarb sulfone in fruits and vegetables is described. Briefly the method consisted of the use of a methanolic extraction, liquid-liquid extraction followed by solid-phase extraction clean-up. Afterwards, the final extract is analyzed by liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (LC-APCI-MS). The specific fragment ion corresponding to [M-74]+ and the protonated molecular [M+H]+ ion were used for the unequivocal determination of aldicarb and its two major metabolites. The analytical performance of the proposed method and the results achieved were compared with those obtained using the common analytical method involving LC with post-column fluorescence detection (FL). The limits of detection varied between 0.2 and 1.3 ng but under LC-FL were slightly lower than when using LC-APCI-MS. However both methods permitted one to achieve the desired sensitivity for analyzing aldicarb and its metabolites in vegetables. The method developed in this work was applied to the trace determination of aldicarb and its metabolites in crop and orange extracts.


Assuntos
Aldicarb/análise , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Inseticidas/análise , Espectrometria de Massas/métodos , Verduras/química , Aldicarb/química , Pressão Atmosférica , Inseticidas/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
J Chromatogr A ; 823(1-2): 109-20, 1998 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-9818398

RESUMO

A competitive enzyme-linked immunosorbent assay (ELISA) method for carbaryl quantitation in crop extracts was validated by liquid chromatography (LC) with diode array detection (DAD). For this purpose, six crops (banana, carrot, green bean, orange, peach and potato) were chosen for recovery and reproducibility studies. The general sample preparation included extraction with methanol followed by liquid-liquid partitioning and clean-up on Celite-charcoal adsorbent column of the vegetable extracts. ELISA samples consisted of a diluted LC extract in assay phosphate buffer (pH 7.5). The potential effect of methanol in these samples was evaluated. It was observed that a maximum content of 10% methanol present in the assay buffer could be tolerated without expressive losses in the ELISA performance. Under these conditions, a IC50 approximately 1.48 micrograms l-1 was obtained. A minimum matrix effect with a 1:50 dilution of the methanolic extracts in assay buffer was noticed, except for green bean samples that inhibited completely the assay. For the vegetable extracts, the ELISA sensitivities varied from 3.9 to 5.7 micrograms l-1, and good recoveries (82-96%) with R.S.D.s ranging from 5.7 to 12.1% were found. An excellent correlation between the LC-DAD and ELISA techniques was obtained. The confirmation of the carbaryl in less concentrated samples was achieved by LC-mass spectrometry interfaced with atmospheric pressure chemical ionisation. The [M + H]+ = 202 and [M + H-57]+ = 145 ions, equivalent to the protonated molecular and 1-naphthol ions, respectively, were used to carbaryl identification in these samples.


Assuntos
Carbaril/análise , Ensaio de Imunoadsorção Enzimática/métodos , Frutas/química , Inseticidas/análise , Espectrometria de Massas , Verduras/química , Brasil , Cromatografia Líquida , Extratos Vegetais/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes
11.
Talanta ; 44(2): 165-8, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18966730

RESUMO

The use of 85% phosphoric acid in borosilicate conical flasks for the dissolution of ilmenites at 230 +/- 10 degrees C is reported. The samples were quantitatively dissolved in less than 13 min. Titanium was determined by both spectrophotometry and inductively coupled plasma atomic emission spectrometry ICP-AES. Vanadium and iron were determined by ICP-AES. In several samples of ilmenites analyzed, the TiO(2) concentration was in the range 10.6-57.5% and those of FeO and V(2)O(5) were in the ranges 31.6-51.4% and 0.39-1.32%, respectively. In the spectrophotometric method, vanadium interference occurs only when the Ti V concentration ratio is <4. In all samples analyzed this ratio was around 12, resulting in no interferences due to vanadium. Hence the ilmenite dissolution procedure using phosphoric acid was compatible with titanium quantification by both spectrophotometry and ICP-AES.

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