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1.
Sci Rep ; 13(1): 4409, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932193

RESUMO

We report on the nature of the interlayer magnetic interactions in NiFe/Cu/Co films. By probing the quasi-static and dynamic magnetic properties of biphase ferromagnetic films, with soft and hard ferromagnetic phases intermediated by a non-magnetic layer, we address aspects of the coupling between magnetic layers. Our results demonstrate the nature of the interlayer magnetic coupling in biphase films. We also disclose the asymmetric magnetoimpedance effect as a fingerprint of the nature of the magnetic interlayer interactions playing key role in the magnetization dynamics of the system. We revisit in literature data and ideas on the asymmetric magnetoimpedance and the nature of the magnetic interactions in biphase ferromagnetic systems. Then, we compare our findings with results for biphase ribbons and microwires. Our observations raise the fundamental similarities and differences in the asymmetric magnetoimpedance of these structures.

2.
Mater Sci Eng C Mater Biol Appl ; 121: 111815, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33579459

RESUMO

This work deals with two new molecule-based materials, namely NiII-complexes of general formulae [Ni(L1)2] (Ni1) and [Ni(L2)2] (Ni2), where L1 = trans-cinnamaldehyde-N(4)-methyl thiosemicarbazone and L2 = trans-cinnamaldehyde-N(4)-ethyl thiosemicarbazone, as potential antitumor agents. Both compounds were characterized by elemental analysis, molar conductivity and spectroscopic techniques (FTIR and NMR). Their molecular structures were obtained by single-crystal X-ray diffraction analysis. Each one crystallizes in a monoclinic space group P 21/c, also the asymmetric unit comprises of one NiII ion located on an inversion centre and one anionic ligand, which acts as a κ2N,S-donor affording a five-membered metallaring. The compounds were screened against two selected tumour cell lines (MCF-7 and A549) and non-tumour fibroblasts cell line (MRC-5) via MTT assays. In both tumour cells, all compounds exhibited higher cytotoxicity than the control drug (cisplatin). The IC50 values ranges of 3.70 - 41.37 µM and 1.06 - 14.91 µM were found for MCF-7 and A549, respectively. Importantly, all of them were less toxicity than cisplatin in MRC-5 with SI values ranged at 11.80 - 86.60. The red blood cell (RBC) assay revealed Ni2 as non-toxic due to its reduced haemolytic effect (0--9% at 1--10 µM). The DNA binding was investigated through a combination of spectrophotometric absorption and emission titrations, electrophoresis, and circular dichroism experiments. As a result, these metal complexes were not able to strongly binding to DNA (Kb values ~104 mol L--1) but suggesting groove-binding interactions. The scavenging ability of them towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical was also evaluated in this work, but no important antioxidant behaviour was detected. Further, the interaction of Ni1 and Ni2 to human serum albumin (HSA) was explored by quenching of tryptophan emission, warfarin competitive assay, and molecular docking protocols. The HSA binding analyses indicated good affinity of both complexes to Sudlow site I (Kb values ⁓103 mol L-1).


Assuntos
Antineoplásicos , Complexos de Coordenação , Tiossemicarbazonas , Antineoplásicos/farmacologia , Humanos , Ligantes , Simulação de Acoplamento Molecular , Estrutura Molecular
3.
J Crit Care ; 44: 398-403, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29306205

RESUMO

PURPOSE: Malnutrition is prevalent in the intensive care units (ICU), yet, there is a paucity of validated assessment tools. Subsequently, this study evaluates the validity of the malnutrition AND-ASPEN tool as an ICU mortality predictor. METHODS: Patients admitted to a large mixed ICU (72 beds) from 2014 to 2016, were followed during stay and had electronic health records on sex, age, Apache II and baseline nutrition assessment collected at admission. Patients with shortstay (<48h) and missing data were excluded. The main hypothesis, hospital mortality prediction, was assessed with a logistic regression model. RESULTS: Patients eligible were 375 where 13% were excluded by the adopted criteria. In the eligible group, 94.2% had AND-ASPEN assessment in their files, showing a malnutrition prevalence rate of 29.7%. Logistic regression (n=327, p=0.0001, r2=0.304, Roc (AUC)=0.80) suggested that mortality risk was 2.5× higher (95%CI, 1.38-4.46, p=0.001) in malnourished patients vs non-malnourished (controlled by sex, Apache II, hospital stay and clinical admission), malnutrition crude OR was 3.04 (95% CI, 1.86-4.97). For every 1-point increase in Apache II, mortality risk rises 14% (95%CI 1.10-1.18, p=0.001). CONCLUSION: This study showed the applicability of the AND-ASPEN tool in the ICU setting as a predictor of mortality.


Assuntos
Estado Terminal/mortalidade , Desnutrição/mortalidade , Idoso , Análise de Variância , Cuidados Críticos/estatística & dados numéricos , Diagnóstico Precoce , Tratamento de Emergência/estatística & dados numéricos , Feminino , Mortalidade Hospitalar , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Desnutrição/diagnóstico , Pessoa de Meia-Idade , Avaliação Nutricional , Estado Nutricional , Estudos Prospectivos
4.
Rev Sci Instrum ; 89(12): 125115, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30599562

RESUMO

In this paper, we report the development of a novel technique in which the magnetoresistance of nanostructures is perturbatively measured by transversally modulating the DC magnetic field. It measures the electrical transport counterpart of the transverse magnetic AC-susceptibility. The technique was developed in a conventional four-probe configuration in which a small DC current flows through the sample and a small transverse AC-field perturbates the equilibrium position of the sample magnetization. Lock-in detection, in-phase with the AC-perturbation, is used to measure the voltage signal between the two inner electrodes of the four-probe station. We successfully demonstrated that this signal is proportional to the product of the first derivative of sample resistance with respect to the equilibrium position of the magnetization times the second derivative of the energy with respect to the equilibrium position of the magnetization. These dependences add new features to the technique investigated here that were not captured by the investigations previously reported on the same subject. To show the effective use of the technique, we discuss its application in measuring magnetic properties of thin magnetic films in the non-saturated regime.

5.
Genet Mol Res ; 15(3)2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27706702

RESUMO

Ramulosis is one of the most aggressive diseases in cotton, and understanding the genetic control of its resistance is imperative for selecting superior cotton genotypes in breeding programs. This study analyzed the inheritance pattern of this resistance using chi-square goodness-of-fit tests to determine the phenotypic proportions of the F2 generation, and a mixed inheritance approach to jointly model major gene and polygenes effects. F1, F2, Rc1, and Rc2 generations were obtained by crossing resistant (BRS Facual, CNPA 2984, or CNPA 2043) and susceptible (Delta Opal, CNPA 999, or CNPA 2161) genotypes, and were assessed under field conditions with artificial inoculation of the pathogen (Colletotrichum gossypii var. cephalosporioides). Genetic control of the trait varied among the crossings. For Delta Opal x BRS Facual and CNPA 2161 x BRS Facual, phenotypic segregations in the F2 generation did not differ from the expected proportions for the hypothesis of duplicate genes (15:1). For Delta Opal x CNPA 2043, the segregation did not differ from the expected proportions for dominant recessive epistasis (13:3). The hypothesis of genetic control by one major gene was supported only for the Delta Opal x CNPA 2043 crossing. Three other crossings showed evidence of polygenes in the inheritance of the trait. In conclusion, major genes and polygenes are likely involved in the genetic control of ramulosis resistance in cotton.


Assuntos
Genes de Plantas/imunologia , Gossypium/genética , Interações Hospedeiro-Patógeno/genética , Herança Multifatorial , Doenças das Plantas/genética , Colletotrichum/patogenicidade , Colletotrichum/fisiologia , Cruzamentos Genéticos , Epistasia Genética , Genótipo , Gossypium/imunologia , Gossypium/microbiologia , Interações Hospedeiro-Patógeno/imunologia , Modelos Genéticos , Fenótipo , Melhoramento Vegetal , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética
6.
J Oral Rehabil ; 42(11): 847-61, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26059857

RESUMO

There is a lack of knowledge about the effectiveness of manual therapy (MT) on subjects with temporomandibular disorders (TMD). The aim of this systematic review is to synthetise evidence regarding the isolated effect of MT in improving maximum mouth opening (MMO) and pain in subjects with signs and symptoms of TMD. MEDLINE(®) , Cochrane, Web of Science, SciELO and EMBASE(™) electronic databases were consulted, searching for randomised controlled trials applying MT for TMD compared to other intervention, no intervention or placebo. Two authors independently extracted data, PEDro scale was used to assess risk of bias, and GRADE (Grading of Recommendations Assessment, Development and Evaluation) was applied to synthetise overall quality of the body of evidence. Treatment effect size was calculated for pain, MMO and pressure pain threshold (PPT). Eight trials were included, seven of high methodological quality. Myofascial release and massage techniques applied on the masticatory muscles are more effective than control (low to moderate evidence) but as effective as toxin botulinum injections (moderate evidence). Upper cervical spine thrust manipulation or mobilisation techniques are more effective than control (low to high evidence), while thoracic manipulations are not. There is moderate-to-high evidence that MT techniques protocols are effective. The methodological heterogeneity across trials protocols frequently contributed to decrease quality of evidence. In conclusion, there is widely varying evidence that MT improves pain, MMO and PPT in subjects with TMD signs and symptoms, depending on the technique. Further studies should consider using standardised evaluations and better study designs to strengthen clinical relevance.


Assuntos
Manipulações Musculoesqueléticas/métodos , Manejo da Dor/métodos , Amplitude de Movimento Articular/fisiologia , Recuperação de Função Fisiológica/fisiologia , Transtornos da Articulação Temporomandibular/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
8.
J Water Health ; 12(3): 526-32, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25252356

RESUMO

The effects of viral gastroenteritis are more devastating in children than in any other age category. Thus, children exposed to the consumption of low quality water are at an increased risk of infection, especially in regions where sanitation is inadequate. The present study aimed to provide a survey of the occurrence of representative enteric viruses: human adenovirus (HAdV), human enteroviruses (hEV), and genogroup A rotavirus (GARV) in tap water samples collected in public schools located at six municipalities of Rio Grande do Sul, southern Brazil. Seventy-three schools were included in the study and tap water samples were analyzed by conventional PCR for the presence of HAdV, hEV, and GARV genomes. hEV showed the highest detection rate (27.4%), followed by HAdV (23.3%), and GARV (16.4%). New approaches to water monitoring should be considered to promote a better water quality and reduce the risk of waterborne diseases, especially considering drinking water to be served to vulnerable individuals.


Assuntos
Adenovírus Humanos/isolamento & purificação , Água Potável/virologia , Enterovirus/isolamento & purificação , Adenovírus Humanos/genética , Brasil , DNA Viral/genética , Enterovirus/genética , Reação em Cadeia da Polimerase , Rotavirus/genética , Rotavirus/isolamento & purificação , Instituições Acadêmicas
9.
Rev. bras. plantas med ; 16(2): 174-181, jun. 2014. graf, tab
Artigo em Português | LILACS | ID: lil-711773

RESUMO

Scutellaria agrestis é utilizada por comunidades ribeirinhas do Amazonas principalmente para o tratamento de otites por via tópica utilizando-se o extrato bruto obtido por maceração. O presente trabalho visou investigar preliminarmente o perfil fitoquímico, a segurança toxicológica e as ações analgésica, anti-inflamatória e antiedematogência do extrato aquoso das folhas de S. agrestis. Foram coletados 80 indivíduos da espécie no horto medicinal da Universidade Nilton Lins, Manaus, Brasil. O perfil fitoquímico foi obtido por meio de prospecção da droga vegetal para heterosídeos cianogênicos, terpenos, compostos fenólicos e alcaloides. A toxicologia foi avaliada pelo teste de toxicidade aguda. As atividades analgésicas/ anti-inflamatórias foram analisadas por meio dos testes de formalina em camundongos e a atividade antiedematogência, pelo teste de edema de pata em ratos. Os metabólitos detectados foram fenóis (taninos hidrolisáveis, cumarinas e várias classes de flavonoides) e terpenos (esteroides livres, saponinas). Não foi possível estabelecer DL50, haja visto que o extrato não provocou a morte de nenhum animal durante o teste de toxicidade aguda, provavelmente devido à ausência de heterosídeos cianogênicos na sua composição. Apesar de não provocar morte, considerou-se que o extrato apresenta uma discreta toxicidade, uma vez que foi observada a ocorrência de espasmos na primeira hora de observação dos animais. O extrato apresentou ainda efeito analgésico e anti-inflamatório significativo nas doses de 30, 100 e 300 mg/kg pelo teste da formalina, sendo o resultado na maior dose equivalente ao obtido com a droga padrão (fentanil). No entanto, não observamos efeito antiedematogênico nas doses testadas durante as 5 horas de registro do edema de pata. Os resultados obtidos nesta pesquisa conferem base científica preliminar quanto à segurança e ao efeito analgésico e antiinflamatório da droga vegetal, o que indica que tal espécie é promissora e expressamente recomendada para maiores estudos farmacológicos in vitro e in vivo.


The Scutellaria agrestis is used by Amazonas riverine communities, especially for otitis externa topical treatment, by using the crude extract obtained by maceration. This study aimed to investigate the preliminary phytochemical profile, the safety/toxicity and the analgesic, anti-inflammatory and antiedematogenic activities of the aqueous extract of the S. agrestis leaves. Eighty individuals were collected at the Nilton Lins University medicinal garden, Manaus, Brazil. The phytochemical profile was obtained through a plant drug survey for cyanogenic heterosides, terpenes, alkaloids and phenolic compounds. The extract safety was evaluated by acute toxicity test. Analgesic and anti-inflammatory activities were accessed using formalin test in mice and the antiedematogenic activity, using paw edema test in mice. We detected phenolic (hydrolysable tannins, coumarins and several classes of flavonoids) and terpenoid (free steroids, saponins) metabolites. We could not establish LD50 because no animals died during the acute toxicity test, probably because of the absence of cyanogenic glycosides on the composition of the extract. However, we found that the extract is slightly toxic as animal spasms were observed in the first hour of the test. The extract showed significant analgesic and anti-inflammatory activity on the formalin test (30, 100 and 300 mg/kg p.o.), and the highest dose result was equivalent to the standard drug (Fentanyl). However, no significant antiedematogenic effect was observed during the paw edema test. The results obtained in this study provide preliminary scientific basis about the safety and analgesic/anti-inflammatory actions of the aqueous extract of S. agrestis, which indicates that this species is a promising option for further in vitro and in vivo pharmacological studies.


Assuntos
Animais , Masculino , Feminino , Camundongos , Extratos Vegetais/análise , Analgésicos/classificação , Anti-Inflamatórios/classificação , Bioensaio/instrumentação , Folhas de Planta/anatomia & histologia , Testes de Toxicidade Aguda , Scutellaria/metabolismo , Compostos Fitoquímicos/análise
10.
Rev. bras. plantas med ; 16(2): 275-282, jun. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-711788

RESUMO

The sesquiterpene lactones lychnopholide and eremantholide C were isolated from Lychnophora trichocarpha Spreng. (Asteraceae), which is a plant species native to the Brazilian Savannah or Cerrado and popularly known as arnica. Sesquiterpene lactones are known to present a variety of biological activities including antitumor activity. The present paper reports on the evaluation of the in vitro antitumor activity of lychnopholide and eremantholide C, in the National Cancer Institute, USA (NCI, USA), against a panel of 52 human tumor cell lines of major human tumors derived from nine cancer types. Lychnopholide disclosed significant activity against 30 cell lines of seven cancer types with IC100 (total growth concentration inhibition) values between 0.41 µM and 2.82 µM. Eremantholide C showed significant activity against 30 cell lines of eight cancer types with IC100 values between 21.40 µM and 53.70 µM. Lychnopholide showed values of lethal concentration 50% (LC50) for 30 human tumor cell lines between 0.72 and 10.00 µM, whereas eremantholide C presented values of LC50 for 21 human tumor cell lines between 52.50 and 91.20 µM. Lychnopholide showed an interesting profile of antitumor activity. The α-methylene-γ-lactone present in the structure of lychnopholide, besides two α,β- unsaturated carbonyl groups, might be responsible for the better activity and higher cytotoxicity of this compound in relation to eremantholide C.


As lactonas sesquiterpênicas licnofolida e eremantolida C foram isoladas de Lychnophora trichocarpha Spreng. (Asteraceae), espécie vegetal nativa do cerrado brasileiro e popularmente conhecida por arnica brasileira. As lactonas sesquiterpênicas são conhecidas por apresentarem variadas atividades biológicas, incluindo atividade antitumoral. O presente artigo relata a avaliação da atividade antitumoral in vitro de licnofolida e eremantolida C frente a um painel de 52 linhagens de células tumorais, provenientes de tumores humanos referentes a nove principais tipos de câncer. Os testes foram conduzidos no National Cancer Institute, USA (NCI, USA). Licnofolida apresentou atividade significativa frente a 30 linhagens de células tumorais referentes a sete tipos de câncer, com valores de CI100 (concentração que inibe 100% do crescimento celular) entre 0,41 µM e 2,82 µM. Eremantolida C mostrou atividade significativa frente a 30 linhagens de células tumorais referentes a oito tipos de câncer, com valores de CI100 entre 21,40 µM e 53,70 µM. Licnofolida apresentou valores de concentração letal 50% (CL50) para 30 linhagens de células tumorais humanas entre 0,72 e 10,00 µM, enquanto eremantolida C mostrou valores de CL50 para 21 linhagens entre 52,50 e 91,20 µM. Licnofolida apresentou um interessante perfil de atividade antitumoral. A presença na estrutura química da licnofolida de uma α-metileno-γ-lactona, além de dois grupos ésteres α,β-insaturados, podem ser responsáveis pela melhor atividade e maior citotoxicidade desta substância em relação à eremantolida C.


Assuntos
Asteraceae/classificação , Lactonas/análise , Técnicas In Vitro/instrumentação
11.
Int J Sports Med ; 34(10): 873-80, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23526594

RESUMO

Although tissue cooling is widely used in the treatment of musculoskeletal injuries there is still controversy about its effects on muscular performance. The combination of cooling and exercise justifies the study of this topic. The aim was to compare the effects of ice pack and cold-water immersion on the muscular performance parameters of plantar flexors and muscular activation of the triceps surae. 41 healthy men (mean age: 22.1 years, SD: 2.9) were randomly assigned to cooling with either ice pack (n=20) or cold-water immersion (n=21). Independent variables were cold modality (ice pack or cold-water immersion) and pre- and post-cooling measurement time. Dependent variables were muscular performance (measured during isometric and concentric contractions of plantar flexors) and electromyography parameters of the triceps surae (median frequency and root mean square amplitude). Dependent-samples t-tests were used to compare pre- and post-cooling data and independent-samples t-tests were used to compare the difference (pre- and post-cooling) between groups. Ice pack increased isometric peak torque (mean: 9.00 Nm, P=0.01) and both cold modalities reduced muscular activation in triceps surae (P<0.0001); Cold-water immersion and ice pack reduced peak torque and total work during dynamic isokinetic contraction at both velocities (mean: -11,00 Nm, P<0.05) and affected muscular activation in different ways. In conclusion, ice pack increases isometric torque, while both ice pack and cold-water immersion decrease concentric muscular performance. These results indicate that these cooling methods should be chosen with caution, considering the type of task required during training or rehabilitation. New studies investigating other muscle groups and joints are necessary.


Assuntos
Crioterapia/métodos , Exercício Físico/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Adolescente , Adulto , Traumatismos em Atletas/terapia , Eletromiografia , , Voluntários Saudáveis , Humanos , Gelo , Imersão , Perna (Membro) , Masculino , Músculo Esquelético/lesões , Variações Dependentes do Observador , Termodinâmica , Água , Adulto Jovem
12.
J Chem Phys ; 137(8): 084504, 2012 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-22938247

RESUMO

We study the effect of confinement in the dynamical behavior of a core-softened fluid. The fluid is modeled as a two length scales potential. This potential in the bulk reproduces the anomalous behavior observed in the density and in the diffusion of liquid water. A series of NpT molecular dynamics simulations for this two length scales fluid confined in a nanotube were performed. We obtain that the diffusion coefficient increases with the increase of the nanotube radius for wide channels as expected for normal fluids. However, for narrow channels, the confinement shows an enhancement in the diffusion coefficient when the nanotube radius decreases. This behavior, observed for water, is explained in the framework of the two length scales potential.

13.
Nano Lett ; 12(8): 4110-6, 2012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22731916

RESUMO

In this work, an atomic force microscope (AFM) is combined with a confocal Raman spectroscopy setup to follow in situ the evolution of the G-band feature of isolated single-wall carbon nanotubes (SWNTs) under transverse deformation. The SWNTs are pressed by a gold AFM tip against the substrate where they are sitting. From eight deformed SWNTs, five exhibit an overall decrease in the Raman signal intensity, while three exhibit vibrational changes related to the circumferential symmetry breaking. Our results reveal chirality dependent effects, which are averaged out in SWNT bundle measurements, including a previously elusive mode symmetry breaking that is here explored using molecular dynamics calculations.

14.
Ergonomics ; 55(1): 78-86, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22176486

RESUMO

In this study, we investigated how experienced and inexperienced subjects handle a box when it could be approached from any of its sides. Subjects moved a box (11 kg) either to a high (HS) or a low surface (LS). Wrist movements and grip force were synchronised and recorded, respectively, by electrogoniometers and an instrumented box. All subjects adopted a lateral-and-bottom grip, with parts of the hands simultaneously placed on the side and bottom of the box. This grip allowed the 50th percentile of wrist movements to be within safe limits, particularly in the sagittal plane. Low force was associated with lowering the box to LS and equally distributed but greater force when lifting to HS. Larger ulnar deviation was recorded when the box was lifted to HS. Only peak of wrist extension differentiated experienced from inexperienced subjects, with experienced presenting larger wrist extension. Alternative box designs are suggested to improve handling in real settings. PRACTITIONER SUMMARY: Understanding worker preferences for box lifting behaviour can contribute to the development of new designs that facilitate the adoption of more efficient postures while reducing the risk of upper-limb musculoskeletal disorders and promoting safer manual material handling.


Assuntos
Força da Mão/fisiologia , Mãos/fisiologia , Amplitude de Movimento Articular/fisiologia , Análise e Desempenho de Tarefas , Articulação do Punho , Análise de Variância , Ergonomia , Humanos , Masculino , Adulto Jovem
15.
Genet Mol Res ; 10(4): 3236-45, 2011 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-22194187

RESUMO

The search for new and effective antitumor agents with fewer cytotoxic side effects on normal tissue has increasingly become important. Lapachol, a natural organic compound isolated from the lapacho tree (Tabebuia avellandedae), is chemically identified as belonging to the naphthoquinone group and is known for its anti-inflammatory, analgesic and antibiotic properties, although there are questions about its effectiveness for treating neoplasic cells. We evaluated the antitumoral effects of lapachol by testing for clones of epithelial tumors in Drosophila melanogaster. Seventy-two-hour old larvae bred from wts/TM3, Sb(1) females and mwh/mwh males, were treated with different concentrations of lapachol (20, 40 and 60 µg/mL). Lapachol alone did not significantly increase the number of epithelial tumors. However, lapachol did significantly reduce the number of tumors provoked by doxorubicin.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proteínas de Drosophila/genética , Drosophila melanogaster/efeitos dos fármacos , Naftoquinonas/farmacologia , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Proteínas Quinases/genética , Tabebuia/química , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Cruzamentos Genéticos , Relação Dose-Resposta a Droga , Doxorrubicina , Drosophila melanogaster/genética , Feminino , Heterozigoto , Humanos , Larva/efeitos dos fármacos , Larva/genética , Masculino , Naftoquinonas/uso terapêutico , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/genética , Neoplasias Epiteliais e Glandulares/induzido quimicamente , Neoplasias Epiteliais e Glandulares/genética , Extratos Vegetais/química
16.
Lett Appl Microbiol ; 53(6): 602-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21895729

RESUMO

AIMS: To investigate the in vitro antiviral activity of Distictella elongata (Vahl) Urb. ethanol extracts from leaves (LEE), fruits (FEE), stems and their main components. METHODS AND RESULTS: The antiviral activity was evaluated against human herpesvirus type 1 (HSV-1), murine encephalomyocarditis virus (EMCV), vaccinia virus Western Reserve (VACV-WR) and dengue virus 2 (DENV-2) by the 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. LEE presented anti-HSV-1 [EC(50) 142.8 ± 5.3 µg ml(-1); selectivity index (SI) 2.0] and anti-DENV-2 activity (EC(50) 9.8 ± 1.3 µg ml(-1) ; SI 1.5). The pectolinarin (1) isolated from LEE was less active against HSV-1 and DENV-2. A mixture of the triterpenoids ursolic, pomolic and oleanolic acids was also obtained. Ursolic and oleanolic acids have shown antiviral activity against HSV-1. A mixture of pectolinarin (1) and acacetin-7-O-rutinoside (2) was isolated from FEE and has presented anti-DENV-2 activity (EC(50) 11.1 ± 1.6 µg ml(-1) ; SI > 45). Besides the antiviral activity, D. elongata has disclosed antioxidant effect. CONCLUSIONS: These data shows that D. elongata has antiviral activity mainly against HSV-1 and DENV-2, besides antioxidant activity. These effects might be principally attributed to flavonoids isolated. SIGNIFICANCE AND IMPACT OF THE STUDY: Distictella elongata might be considered a promising source of anti-dengue fever phytochemicals.


Assuntos
Antivirais/farmacologia , Bignoniaceae/química , Vírus da Dengue/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Brasil , Dengue/tratamento farmacológico , Humanos , Camundongos , Vírus/efeitos dos fármacos
17.
Neuroepidemiology ; 36(2): 105-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21335981

RESUMO

BACKGROUND: Spinal muscular atrophy is a common autosomal recessive neuromuscular disorder caused by mutations in the SMN1 gene. Identification of spinal muscular atrophy carriers has important implications for individuals with a family history of the disorder and for genetic counseling. The aim of this study was to determine the frequency of carriers in a sample of the nonconsanguineous Brazilian population by denaturing high-performance liquid chromatography (DHPLC). METHODS: To validate the method, we initially determined the relative quantification of DHPLC in 28 affected patients (DHPLC values: 0.00) and 65 parents (DHPLC values: 0.49-0.69). Following quantification, we studied 150 unrelated nonconsanguineous healthy individuals from the general population. RESULTS: Four of the 150 healthy individuals tested (with no family history of a neuromuscular disorder) presented a DHPLC value in the range of heterozygous carriers (0.6-0.68). CONCLUSIONS: Based on these results, we estimated there is a carrier frequency of 2.7% in the nonconsanguineous Brazilian population, which is very similar to other areas of the world where consanguineous marriage is not common. This should be considered in the process of genetic counseling and risk calculations.


Assuntos
Heterozigoto , Atrofia Muscular Espinal/etnologia , Atrofia Muscular Espinal/genética , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Adulto , Idoso , Brasil/etnologia , Feminino , Testes Genéticos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Muscular Espinal/diagnóstico , Adulto Jovem
18.
Cell Mol Neurobiol ; 31(3): 429-36, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21191647

RESUMO

It is well established that the involvement of reactive species in the pathophysiology of several neurological diseases, including phenylketonuria (PKU), a metabolic genetic disorder biochemically characterized by elevated levels of phenylalanine (Phe). In previous studies, we verified that PKU patients (treated with a protein-restricted diet supplemented with a special formula not containing L-carnitine and selenium) presented high lipid and protein oxidative damage as well as a reduction of antioxidants when compared to the healthy individuals. Our goal in the present study was to evaluate the effect of Phe-restricted diet supplemented with L-carnitine and selenium, two well-known antioxidant compounds, on oxidative damage in PKU patients. We investigated various oxidative stress parameters in blood of 18 treated PKU patients before and after 6 months of supplementation with a special formula containing L-carnitine and selenium. It was verified that treatment with L-carnitine and selenium was capable of reverting the lipid peroxidation, measured by thiobarbituric acid-reactive species, and the protein oxidative damage, measured by sulfhydryl oxidation, to the levels of controls. Additionally, the reduced activity of glutathione peroxidase was normalized by the antioxidant supplementation. It was also verified a significant inverse correlation between lipid peroxidation and L-carnitine blood levels as well as a significant positive correlation between glutathione peroxidase activity and blood selenium concentration. In conclusion, our results suggest that supplementation of L-carnitine and selenium is important for PKU patients since it could help to correct the oxidative stress process which possibly contributes, at least in part, to the neurological symptoms found in phenylketonuric patients.


Assuntos
Antioxidantes/farmacologia , Carnitina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fenilcetonúrias/fisiopatologia , Selênio/farmacologia , Adolescente , Antioxidantes/administração & dosagem , Antioxidantes/uso terapêutico , Carnitina/administração & dosagem , Carnitina/uso terapêutico , Suplementos Nutricionais , Humanos , Fenilcetonúrias/sangue , Fenilcetonúrias/dietoterapia , Espécies Reativas de Oxigênio/metabolismo , Selênio/administração & dosagem , Selênio/uso terapêutico , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Adulto Jovem
19.
Nanotechnology ; 20(34): 345301, 2009 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-19652274

RESUMO

Here we describe a lithography scheme based on the local anodic oxidation of germanium film by a scanning atomic force microscope in a humidity-controlled atmosphere. The oxidation kinetics of the Ge film were investigated by a tapping mode, in which a pulsed bias voltage was synchronized and applied with the resonance frequency of the cantilever, and by a contact mode, in which a continuous voltage was applied. In the tapping mode we clearly identified two regimes of oxidation as a function of the applied voltage: the trench width increased linearly during the vertical growth and increased exponentially during the lateral growth. Both regimes of growth were interpreted taking into consideration the Cabrera-Mott mechanism of oxidation applied to the oxide/Ge interface. We also show the feasibility of the bottom-up fabrication process presented in this work by showing a Cu nanowire fabricated on top of a silicon substrate.

20.
Braz. j. phys. ther. (Impr.) ; 12(6): 460-467, Nov.-Dec. 2008. ilus, graf, tab
Artigo em Inglês, Português | LILACS | ID: lil-504887

RESUMO

INTRODUCTION: Different sources of variations, such as electrogoniometer characteristics and procedures, may affect the accuracy and precision of movement measurements during gait. OBJECTIVE: To quantify the variations and compare the effects produced by different sources of variation in electrogoniometric gait recordings: the sensors, procedures (trials) and the knee joint. METHODS: Knee flexion/extension and valgus/varus movements were recorded during gait on the treadmill. The recordings were partitioned into strides and normalized in time using a routine developed in MatLab. Mean curves for the knee during gait were derived from 50 strides, and seven conditions were evaluated: one comparing pairs of sensors; two comparing pairs of different trials (including variations due to sensors); and four comparing the right and left knees (including variations due to sensors and trials). Mean standard deviations of the differences were calculated. To estimate the variations relating to the trial and the knee joint, the compound standard deviations were transformed into variances and split into their components. RESULTS: The variation introduced by pairs of sensors in the same model applied in one trial was smaller than the variation introduced by the same sensor used in two consecutive trials. Furthermore, the variation introduced by the difference between the right and left knees was greater than the variation introduced by the difference between sensors (A and B) and trials (1 and 2). CONCLUSIONS: It is, therefore, preferable to use different sensors in the same data recording (simultaneous) than use the same sensor in two different recordings (consecutive).


INTRODUÇÃO: Diferentes fontes de variação, tais como características do eletrogoniômetro e procedimentos podem afetar a acurácia e precisão das medidas do movimento durante a marcha. OBJETIVO: Quantificar a variação e comparar o efeito das diferentes fontes de variação nos registros eletrogoniométricos da marcha: os sensores, os procedimentos (coletas consecutivas) e a articulação do joelho. MÉTODOS: Movimentos de flexo-extensão e valgo-varo do joelho foram registrados durante a caminhada na esteira. Os registros foram divididos em passadas e normalizados no tempo usando uma rotina desenvolvida em MatLab. As curvas médias do joelho durante a marcha foram derivadas de 50 passadas, e sete condições foram avaliadas: uma para comparar dois sensores; duas para comparar duas diferentes coletas (incluindo a variação do sensor), e quatro para comparar os joelhos direito e esquerdo (incluindo a variação dos sensores e coletas). Os desvios-padrão médios das diferenças foram calculados. Para estimar as variações devido às coletas e à articulação do joelho, os desvios-padrão compostos foram transformados em variâncias e seus componentes isolados. RESULTADOS: A variação introduzida por dois sensores do mesmo modelo aplicados em uma coleta foi menor do que a variação introduzida pelo mesmo sensor usado em duas coletas consecutivas. Ainda, a variação introduzida pela diferença entre os joelhos direito e esquerdo foi maior do que a variação introduzida pela diferença entre os sensores (A e B) e as coletas (1 e 2). CONCLUSÕES: Assim, é preferível usar diferentes sensores na mesma coleta de dados (simultânea) do que usar o mesmo sensor em dois registros diferentes (consecutivos).

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