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1.
Integr Org Biol ; 3(1): obab025, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34589667

RESUMO

Glucocorticoids and melatonin (MEL) show integrated and complex immunomodulatory effects, mostly described for endotherms, yet underexplored in amphibians. In this context, the RT-qPCR of molecules mediating inflammatory processes in amphibians is a valuable tool to explore the relationships among molecular biology, endocrine mediators, and immune response in these animals. In this study, toads (Rhinella diptycha) received an intraperitoneal saline injection or lipopolysaccharide (LPS; 2 mg/kg). Six hours post-injection, we analyzed plasma corticosterone (CORT) and MEL levels and pro- and anti-inflammatory molecules (IL-1ß, IL-6, IL-10, IFN-γ, and C1s). We found increased CORT and decreased MEL levels in response to LPS. Also, IL-1ß, IL-6, and IL-10 were upregulated in LPS-injected toads compared with saline-injected toads. Overall, our results demonstrate an LPS-induced inflammatory response with endocrine and immune modulation in R. diptycha toads, exhibiting expected patterns for an inflammatory stimulus within this time frame (6 h post-injection). Toads were responsive to LPS by secreting different cytokines, such as proinflammatory cytokines IL-1ß and IL-6, related to immune cell attraction to inflammatory sites and the anti-inflammatory cytokine IL-10, which limits the rate of leukocyte infiltration, inflammation, and downregulates the expression of proinflammatory cytokines. Increased circulating CORT levels are probably associated with the activation of the hypothalamus-pituitary-interrenal axis by the LPS and the endocrine actions of IL-6. Furthermore, decreased circulating MEL levels are likely due to inhibited MEL secretion by the pineal gland by inflammatory stimuli, indicating the activation/existence of the immune-pineal axis in amphibians.


Os glicocorticoides e a melatonina (MEL) apresentam efeitos imunomoduladores integrados e complexos, principalmente descritos para endotérmicos, porém pouco explorados em anfíbios. Nesse contexto, o RT-qPCR de moléculas mediadoras de processos inflamatórios em anfíbios é uma ferramenta valiosa para explorar as relações entre biologia molecular, mediadores endócrinos e resposta imune nesses animais. Neste estudo, sapos (Rhinella diptycha) receberam uma injeção intraperitoneal de solução salina ou lipopolissacarídeo (LPS; 2 mg/kg). Seis horas após a injeção, analisamos as concentrações plasmáticas de corticosterona (CORT) e MEL e moléculas pró e anti-inflamatórias (IL-1ß, IL-6, IL-10, IFN-γ e C1s). Encontramos aumento de CORT e diminuição da concentração de MEL em resposta ao LPS. Além disso, IL-1ß, IL-6 e IL-10 foram reguladas positivamente em sapos injetados com LPS em comparação com os sapos injetados com solução salina. No geral, nossos resultados demonstram uma resposta inflamatória induzida por LPS com modulação endócrina e imunológica em sapos R. diptycha, exibindo padrões esperados para um estímulo inflamatório dentro deste período (6 h pós-injeção). Os sapos foram responsivos ao LPS secretando diferentes citocinas, como as citocinas pró-inflamatórias IL-1ß e IL-6, relacionadas à atração de células imunes para os sítios inflamatórios e a citocina anti-inflamatória IL-10, que limita a taxa de infiltração leucocitária, inflamação, e diminui a expressão de citocinas pró-inflamatórias. As concentrações elevadas de CORT circulante estão provavelmente associados à ativação do eixo hipotálamo-hipófise-interrenal pelo LPS e às ações endócrinas da IL-6. Além disso, a diminuição da concentração circulante de MEL é provavelmente devida à inibição da secreção de MEL pela glândula pineal por estímulos inflamatórios, indicando a ativação/existência do eixo imune-pineal em anfíbios.

2.
Colloids Surf B Biointerfaces ; 196: 111342, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32889449

RESUMO

In this study, cotton fabrics decorated with Ag/AgCl and Ag/AgBr NPs were produced by a simple hydrothermal treatment using AgCl and AgBr as precursors. Their morphological features as well as, chemical composition and structural and luminescence properties were compared. Their water disinfection aptitude against E. coli and S. aureus was also investigated under solar illumination in batch as well asin dynamic conditions. The highest activity was observed for Cot-Ag/AgCl with a quasi-complete inactivation of E. coli and S. aureus(1.5 × 107cfu mL-1) within 15 min illumination. Disinfection efficiency under continuous flow was also tested using a home-made photoreactor and the cotton fabrics with the most efficient photocatalyst (Ag/AgCl). It has shown to be efficient at least for 10 cycles revealing the robustness of the functionalization. The mechanism of photocatalytic disinfection was explained in terms of the surface plasmon resonance (SPR) induced by the presence of Ag NPs, the resulting holes, h+, being one of the most intervenient species in the disinfection mechanism. The difference in the photocatalytic efficiency between AgCl and AgBr functionalized cotton was attributed to differences in the carriers (h+and e-) lifetime. This work provides a proof of concept for the potential applicability of Cot-Ag/AgCl or Cot-Ag/AgBr for in-flow potabilization of water under solar illumination.


Assuntos
Compostos de Prata , Prata , Catálise , Escherichia coli , Luz , Staphylococcus aureus
3.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1773-1777, Sept.-Oct. 2020. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1131526

RESUMO

This study describes a case of a dog with a lacerated penile tear treated with partial penectomy followed by successful semen collections for artificial insemination. A 1.5-year-old Jack Russel Terrier with normal libido, genital organs and semen, had a penile laceration after copulation. The dog underwent a partial penectomy without orchiectomy, thus preserving the possibility of semen collection. Semen was successfully collected at 45 and 53 days after surgery, and it was used for artificial insemination of two bitches, one of which became pregnant. Therefore, this report demonstrated that semen may be collected from dogs with partial penectomy for artificial insemination, this technique has the potential to preserve fertility of dogs with penile lesions that require penectomy.(AU)


Este estudo descreve o caso de um cão que teve laceração peniana tratada por penectomia parcial seguida de coleta de sêmen para inseminação artificial bem sucedida. Um cão Jack Russel Terrier de 1,5 anos, com libido, órgãos genitais e sêmen normais, teve laceração peniana após cópula. O cão foi parcialmente penectomizado sem orquiectomia, preservando a possibilidade de coleta de sêmen. A coleta de sêmen foi bem sucedida 45 e 53 dias após a cirurgia, sendo utilizado para inseminação artificial de duas cadelas, uma delas se tornando gestante. Portanto, sêmen para inseminação artificial pode ser coletado em cães parcialmente penectomizados, esta técnica revelando ser uma potencial forma de preservação da fertilidade de cães com lesões penianas que necessitem penectomia.(AU)


Assuntos
Animais , Masculino , Cães , Pênis/cirurgia , Inseminação Artificial/veterinária , Coleta de Tecidos e Órgãos/veterinária , Lacerações/veterinária
4.
Opt Express ; 28(8): 11666-11681, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32403673

RESUMO

Single-pixel imaging is an imaging technique that has recently attracted a lot of attention from several areas. This paper presents a study on the influence of the Hadamard basis ordering on the image reconstruction quality, using simulation and experimental methods. During this work, five different orderings, Natural, Walsh, Cake-cutting, High Frequency and Random orders, along with two different reconstruction algorithms, TVAL3 and NESTA, were tested. Also, three different noise levels and compression ratios from 0.1 to 1 were evaluated. A single-pixel camera was developed using a digital micromirror device for the experimental phase. For a compression ratio of 0.1, the Cake-cutting order achieved the best reconstruction quality, while the best contrast was achieved by Walsh order. For compression ratios of 0.5, the Walsh and Cake-cutting orders achieved similar results. Both Walsh and Cake-cutting orders reconstructed the images with good quality using compression ratios from 0.3. Finally, the TVAL3 algorithm showed better image reconstruction quality, in comparison with NESTA, when considering compression ratios from 0.1 to 0.5.

5.
Arq. bras. med. vet. zootec. (Online) ; 72(2): 641-646, Mar./Apr. 2020. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1128497

RESUMO

Cheese whey is a nutritious byproduct in the dairy industry, however, due to low commercial value, its use as a milk adulterant is a common practice not easily detected by routine analysis. In Brazil, quantification of caseinomacropeptide (CMP) index, using High Performance Liquid Chromatography (HPLC), is officially used to investigate illegal cheese whey addition to milk. Milk with CMP index above 30mg/L is considered not suitable for human consumption. The objective of this research was to report the CMP index in 185 samples of pasteurized milk, representing 73 commercial brands produced in 51 counties and ten mesoregions of the state of Minas Gerais, from 2011 to 2013 (58 samples) and 2015 to 2017 (127 samples). CMP index was considered normal (up to 30mg/L) in 75.1% of the samples. However, 21.1% presented CMP index above 75mg/L and 3.8% from 31 to 75mg/L. CMP index above 75mg/L was found in 17.4% of the samples produced during the dry season (April to September) and in 24.7% during the rainy season (October to March). These data point to the need of more efficient monitoring and inspection processes to hinder adulteration with cheese whey addition to milk.(AU)


Assuntos
Peptídeos , Caseínas/análise , Leite , Pasteurização , Fraude , Brasil , Contaminação de Alimentos/análise
6.
Clin Chim Acta ; 499: 16-23, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31479651

RESUMO

BACKGROUND: Systemic Lupus Erythematosus (SLE) is an autoimmune, multisystemic disease. Currently diagnosis depends on complex criteria developed by the American College of Rheumatology. Moreover, the lack of specific biomarkers also challenges the diagnosis. METHODS: Inflammatory biomarkers such as IL-8, IP-10, MIG, MIP-1α and RANTES were measured in serum samples from SLE patients and subjects in control groups (patients with other autoimmune diseases and healthy individuals). Forty-six SLE patients (22 patients with low activity, SLEDAI-2 K ≤ 4, 24 patients with moderate/high activity, SLEDAI-2 K > 4), 42 patients with other autoimmune diseases (OAD group), and 8 healthy volunteers participated in this study. RESULTS: MIG (p < .001) and RANTES (p < .001) concentrations in SLE patients and healthy controls, and IP-10 concentrations in SLE patients with different disease activities (low activity, p < .01, moderate/high activity, p < .05) differed significantly. IL-8 (p < .001) and MIP-1α (p < .001) concentrations in SLE patients differed from those in patients from the OAD group. IL-8 (p < .05), IP-10 (p < .01), MIG (p < .05), MIP-1α (p < .001), and RANTES (p < .05) were correlated with SLE activity; their concentrations in SLE patients with low and moderate/high activity differed significantly. CONCLUSIONS: Given the findings of this study, one can envision the possibility of future use of some of these cytokines to assist in the screening of SLE patients, or even in monitoring disease activity.


Assuntos
Citocinas/sangue , Citometria de Fluxo , Lúpus Eritematoso Sistêmico/diagnóstico , Adulto , Biomarcadores/sangue , Feminino , Humanos , Lúpus Eritematoso Sistêmico/sangue , Masculino , Pessoa de Meia-Idade
7.
Braz. j. biol ; 79(2): 248-256, Apr.-June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-989445

RESUMO

Abstract The use of GMO expressing Bt toxin in soybean production has increased significantly in the last years in Brazil in order to manage the damage caused by lepidopteran pests. In this study, we compared the richness and abundance of owlet moths (Noctuoidea) associated with Bt and non-Bt soybean. We determined the temporal variations as a function of phenology, and correlated the population variations of the most common species with meteorological variables. The research was conducted at the experimental area of Embrapa Cerrados. The collection method used was differentiated being suppressive and absolute. A total of 13 species were collected, of which eight occurred on Bt soybeans. The most representative taxa were Chrysodeixis includens (72.87%), Anticarsia gemmatalis (18.17%) and Spodoptera spp (5.22%). The number of larvae belonging to species targeted by the Bt technology was 10 times lower on Bt than on non-Bt soybeans. Utetheisa ornatrix and Elaphria deltoides were recorded on soybean for the first time, observing larvae of both species in non-Bt soybean and those of U. ornatrix also in Bt soybean. Only A. gemmatalis larvae correlated (p <0.05) negatively with precipitation. This study provided field information on the abundance and species richness of owlet moths on non-Bt soybeans, associated with the effects of Bt soybean. When considering the different levels of infestation between cultivars as a criterion, larvae monitoring is of substantial importance in order to develop the lost control program.


Resumo O uso de OGM que expressam toxina Bt na produção de soja tem aumentado significativamente nos últimos anos no Brasil e são utilizados para conter os danos causados ​​pelos lepidópteros pragas. Neste estudo comparamos a riqueza e a abundância de Noctuoides (Noctuoidea) associados à soja Bt e não-Bt. Determinamos as variações temporais em função da fenologia e correlacionamos às variações populacionais das espécies mais comuns com variáveis ​​meteorológicas. A pesquisa foi conduzida na área experimental da Embrapa Cerrados. O método de coleta utilizado foi diferenciado sendo supressivo e absoluto. Um total de 13 espécies foram coletadas, das quais oito ocorreram em soja Bt. Os taxa mais representativos foram Chrysodeixis includens, Anticarsia gemmatalis e Spodoptera spp. O número de larvas pertencentes às espécies alvo da tecnologia Bt foram 10 vezes menores na soja Bt do que em soja não-Bt . Utetheisa ornatrix e Elaphria deltoides foram registradas na soja pela primeira vez, observando-se larvas de ambas espécies na soja não-Bt e as de U. ornatrix também na soja Bt. Somente as larvas de A. gemmatalis se correlacionaram (p <0,05) negativamente com a precipitação. Este estudo forneceu informações em campo sobre a abundância e riqueza de espécies na soja não- Bt, associada aos efeitos da soja Bt. A importância do monitoramento das lagartas é substancial, a fim de tomar a melhor decisão de controle, considerando-se os diferentes níveis de infestação entre cultivares como critério.


Assuntos
Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Endotoxinas/genética , Endotoxinas/farmacologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Glycine max/genética , Glycine max/parasitologia , Brasil , Controle Biológico de Vetores , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/parasitologia , Larva/efeitos dos fármacos , Mariposas/efeitos dos fármacos
8.
Int J Biol Macromol ; 128: 902-910, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30716374

RESUMO

The functionalization of cotton fabric with photoactive TiO2-Ag-AgBr nanostructured layer has been successfully developed using a low temperature non-aqueous sol-gel route and aqueous suspension of AgBr. Evidence for the growth of TiO2 layer and the immobilization of AgBr nanoparticles have been confirmed by Raman, XRD and XPS. GSDR analysis revealed a strong absorption in the visible region brought by surface Plasmon resonance (SPR) of Ag nanocrystals generated at the surface of AgBr. The XPS evidenced the presence of Ag+, Ag0 and bromine, suggesting that Ag0 formed a shell around the deposited AgBr. The immobilized TiO2-Ag-AgBr heterostructured layer imparts a strong photocatalytic activity under visible light for the degradation of dyes in aqueous solution as well as of dimethyl methylphosphonate (DMMP), a chemical warfare agent simulant. These new catalytically active functionalized fabrics, with self-detoxification properties, have great potential for application in chemical protective clothes and might offer new opportunities for the design of functional materials for toxic chemical protection.


Assuntos
Brometos/química , Corantes/química , Fibra de Algodão , Organofosfatos/química , Processos Fotoquímicos , Compostos de Prata/química , Prata/química , Titânio/química , Catálise , Corantes/isolamento & purificação , Nanoestruturas/química , Organofosfatos/isolamento & purificação , Organofosfatos/toxicidade , Temperatura , Água/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água
9.
Braz J Biol ; 79(2): 248-256, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29995136

RESUMO

The use of GMO expressing Bt toxin in soybean production has increased significantly in the last years in Brazil in order to manage the damage caused by lepidopteran pests. In this study, we compared the richness and abundance of owlet moths (Noctuoidea) associated with Bt and non-Bt soybean. We determined the temporal variations as a function of phenology, and correlated the population variations of the most common species with meteorological variables. The research was conducted at the experimental area of Embrapa Cerrados. The collection method used was differentiated being suppressive and absolute. A total of 13 species were collected, of which eight occurred on Bt soybeans. The most representative taxa were Chrysodeixis includens (72.87%), Anticarsia gemmatalis (18.17%) and Spodoptera spp (5.22%). The number of larvae belonging to species targeted by the Bt technology was 10 times lower on Bt than on non-Bt soybeans. Utetheisa ornatrix and Elaphria deltoides were recorded on soybean for the first time, observing larvae of both species in non-Bt soybean and those of U. ornatrix also in Bt soybean. Only A. gemmatalis larvae correlated (p <0.05) negatively with precipitation. This study provided field information on the abundance and species richness of owlet moths on non-Bt soybeans, associated with the effects of Bt soybean. When considering the different levels of infestation between cultivars as a criterion, larvae monitoring is of substantial importance in order to develop the lost control program.


Assuntos
Proteínas de Bactérias , Endotoxinas , Glycine max , Proteínas Hemolisinas , Larva/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Controle Biológico de Vetores , Plantas Geneticamente Modificadas , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Brasil , Endotoxinas/genética , Endotoxinas/farmacologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/parasitologia , Glycine max/genética , Glycine max/parasitologia
10.
Photochem Photobiol Sci ; 18(2): 336-342, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30310913

RESUMO

Squaraine dyes have recently attracted interest as potential second generation photosensitizers for photodynamic therapy. Several cationic aminosquaraine dyes bearing benzoselenazole terminal nuclei were synthezised and their cytotoxic activity was tested against four different human tumor cell lines - breast (MCF-7), non-small cell lung (NCI-H460), cervical (HeLa) and hepatocellular (HepG2) carcinomas - and against a non-tumor porcine liver primary cell line (PLP2), both in the absence of light and under irradiation. All dyes, which displayed strong absorption within the phototherapeutic window, were found to exhibit photodynamic activity and were shown to be, in most cases, more cytotoxic, both in the dark and upon irradiation, than their benzothiazole analogues.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Ciclobutanos/síntese química , Ciclobutanos/farmacologia , Fenóis/síntese química , Fenóis/farmacologia , Processos Fotoquímicos , Selênio/química , Antineoplásicos/química , Linhagem Celular Tumoral , Técnicas de Química Sintética , Ciclobutanos/química , Humanos , Fenóis/química
11.
Carbohydr Polym ; 199: 31-40, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30143134

RESUMO

Aiming the degradation of harmful molecules under visible light, new photocatalytic systems were created. For this purpose, the surface of chitosan thin films was modified in heterogeneous phase via a simple and straightforward mild chemical process: chemisorption of silver ions followed by the synthesis in situ of TiO2 at low temperature (100 °C). A high photocatalytic activity under visible light was observed, leading to the degradation and/or mineralization of different organic products such as o-toluidine, salicylic acid and 4-aminomethyl benzoic acid. This efficiency is partly attributed to the formation of Ag NPs and also to the unexpected appearance of AgCl NPs, likely formed from the residual chlorine contained in the chitosan. The resulting TiO2/Ag/AgCl/Chitosan system is easy to prepare under mild conditions, avoiding calcination treatments and opens new perspectives for the production of visible light-driven photocatalysts. Samples were analysed by different techniques: XRD, Raman, FE-SEM, XPS, TGA, GSDR, LIF and LIP.

12.
Arq. bras. med. vet. zootec. (Online) ; 70(5): 1649-1654, set.-out. 2018. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-947796

RESUMO

O objetivo deste trabalho foi analisar as leituras de composição do leite cru por meio de espectrofotometria FTIR, utilizando-se curva de regressão PLS, bem como as contagens de células somáticas e bacteriana total por citometria de fluxo, após adição de amido e sacarose. O leite cru foi adulterado com três concentrações de amido e sacarose (0,1%, 0,5% e 1%), colocado em frascos contendo bronopol ou azidiol, os quais foram armazenados em duas temperaturas (7±2°C e 25±2°C ). As análises foram realizadas após zero, três, 24, 48, 72 e 168 horas de armazenamento. O modelo de regressão linear múltipla foi utilizado para análise estatística. A adição de amido e sacarose resultou em mudança significativa (P<0,05) para todas as variáveis dependentes. O leite adulterado com amido resultou em aumento nas leituras de gordura, proteína, lactose, sólidos totais (ST), sólidos não gordurosos (SNG), CCS e CBT e em diminuição das leituras de caseína, do nitrogênio ureico do leite (NUL) e do ponto de congelamento. O leite adulterado com sacarose resultou no aumento das leituras da lactose, ST, SNG e NUL, enquanto as leituras de proteína, caseína, ponto de congelamento e CCS diminuíram. Este trabalho evidencia a importância do monitoramento de adulterantes reconstituintes no leite por afetarem os resultados analíticos da qualidade do leite, obtidos por métodos eletrônicos.(AU)


Assuntos
Análise de Fourier , Leite/química , Sacarose , Espectrofotometria/veterinária
13.
Carbohydr Polym ; 176: 336-344, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28927616

RESUMO

A simple approach to functionalize cotton fabrics with Au and TiO2 nanostructured layer is presented. Hybrid fabrics (Cot-Au-TiO2) are prepared through reduction of AuCl4- on cotton, followed by a non-aqueous sol-gel procedure using tetrabutyltitanate and a hydrothermal treatment at 110°C. The generation of crystalline TiO2 is confirmed by Raman spectroscopy. The fibres morphology and their roughness are characterized by AFM and FE-SEM. XPS shows how the concentration of the NPs precursors (Au and TiO2) affects the layer composition. GSDR (Ground State Diffuse Reflectance Absorption Spectroscopy) and LIL (Laser induced luminescence) reveal a strong quenching effect induced by Au NPs. Photocatalytic activity measured through the Remazol Blue (RB) degradation reveals an enhancement under visible light, which increases with Au loading. This strong enhancement is explained through the surface plasmon resonance brought by Au NPs.

14.
Carbohydr Polym ; 151: 160-171, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27474555

RESUMO

Porphyrins and some of its derivatives are well known and widely used as photosensitizers (PSs) for Photodynamic Therapy of Cancer (PDT). The present study regards the characterization and evaluation of a synthesized asymmetric porphyrin dye in solution to be used as PS for PDT. This molecule was also incorporated into biopolymeric films composed by chitosan, polyethylene glycol (PEG) and gelatin in order to overtake some of the disadvantages inherent to the PS, but more important, to evaluate the potential of a system composed by the porphyrin/biopolymer to be applied as localized therapeutic agents. FTIR spectroscopy showed a strong interaction between the polymers involved in the preparation of the films under study: film 1: chitosan, film 2: chitosan/PEG and film 3: chitosan/gelatin. Photochemical studies were performed for the dye in solution and into the three different biopolymeric films. Ground state absorption showed the characteristic bands of these kinds of dyes in solution and also incorporated into the films. The films composed by porphyrin/chitosan and porphyrin into chitosan/gelatin, revealed the presence of non-emissive aggregates exhibiting a strong quenching effect in the fluorescence intensity, quantum yields and lifetimes. In this way, the system composed by the porphyrin incorporated into the chitosan/PEG film presents the best fluorescence quantum yield and lifetime. The transient absorption spectra were obtained for all the systems indicating the formation of an excited triplet state of the porphyrins following excitation, which takes special importance in the generation of phototoxic species namely singlet oxygen. Singlet oxygen quantum yields were also determined and the results obtained were very promising for the dye in solution but also for the dye into the different substrates. The release of the dye from the three different films onto a buffer solution was evaluated and we conclude that after a few days the dye was completely released by the substrates in acidic conditions. Confocal microscopy was used for the determination of the intracellular localization of the compound under study onto HeLa cells (human cervical cancer cells line). The evaluation of the PSs anticancer activity assumes special importance for PDT studies. The system should be less toxic in the dark and more active when irradiated, therefore, toxicity in the dark and phototoxicity studies onto HeLa cells were performed.


Assuntos
Quitosana , Corantes , Gelatina , Fármacos Fotossensibilizantes , Polietilenoglicóis , Porfirinas , Sobrevivência Celular/efeitos dos fármacos , Quitosana/administração & dosagem , Quitosana/química , Corantes/administração & dosagem , Corantes/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Fluorescência , Gelatina/administração & dosagem , Gelatina/química , Células HeLa , Humanos , Luz , Neoplasias/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/química , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Porfirinas/administração & dosagem , Porfirinas/química
15.
Carbohydr Polym ; 141: 229-37, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-26877017

RESUMO

A green, safe and fast procedure is presented for in situ generation of nanoparticles (NPs) of cuprous oxide (Cu2O) onto cotton fibres at room temperature using water as a solvent. The method is based on a mild surface oxidation of cellulose fibres to generate in a controlled way carboxylic groups acting as a binding site for the adsorption of Cu(2+) via electrostatic coordination. Then, the adsorbed Cu(2+) ions were readly converted into Cu2O by dipping the treated cotton fibres into a aqueous solution of a reducing agent. Field-emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD), as well as UV-vis absorption and emission spectroscopic methods were used to analyse the size, morphology, chemical composition and the crystalline structure of the generated nanoparticles on the fabrics. The morphology of the ensuing Cu2O nanoparticles was shown to be dependent on the reduycing agent used. Antibacterial properties of the modified fibres were also investigated.


Assuntos
Antibacterianos/química , Cobre/química , Fibra de Algodão , Nanopartículas Metálicas/química , Celulose/análogos & derivados , Química Verde/métodos , Oxirredução
16.
J Phys Chem B ; 120(7): 1212-20, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26829502

RESUMO

In this work, a squaraine dye CS5 was characterized and evaluated for its potential in photodynamic therapy. The studies were performed in ethanol and also in a powdered biopolymer, in this case chitosan. Ground state absorption, absolute fluorescence quantum yields, fluorescence lifetimes, and transient absorption were determined in order to evaluate the advantage of adsorbing the dye onto a biopolymer. Several concentrations of the dye, adsorbed onto chitosan, were prepared in order to evaluate the concentration effect on the photophysical parameters under study. A remarkable increase in the fluorescence quantum yield and lifetimes was detected when compared with the dye in solution. Also, a very clear dependence of the fluorescence quantum yield on the concentration range was found. A lifetime distribution analysis of these systems fluorescence evidenced the entrapment of the dye onto the chitosan environment with a monoexponential decay which corresponds to the monomer emission in slightly different environments. The transient absorption spectrum was obtained without sensitization indicating the existence of a triplet state which takes special importance in the generation of phototoxic species namely singlet oxygen. The subcellular localization of a photosensitizer is critical for efficient photoinduced cell death, in this way, colocalization studies were performed within HeLa cell line (human cervical carcinoma) through confocal microscopy. Toxicity in the dark and phototoxicity of CS5 were also evaluated for the same cellular model.


Assuntos
Quitosana/química , Corantes/farmacologia , Ciclobutanos/farmacologia , Portadores de Fármacos/química , Fenóis/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Adsorção , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Colo do Útero/efeitos dos fármacos , Colo do Útero/efeitos da radiação , Corantes/administração & dosagem , Corantes/química , Corantes/farmacocinética , Ciclobutanos/administração & dosagem , Ciclobutanos/química , Ciclobutanos/farmacocinética , Feminino , Fluorescência , Células HeLa , Humanos , Luz , Fenóis/administração & dosagem , Fenóis/química , Fenóis/farmacocinética , Fotoquimioterapia , Fotólise , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacocinética , Raios Ultravioleta
17.
Mycology ; 6(1): 28-34, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-26000196

RESUMO

The vinasse is a by-product generated during the manufacture of alcohol from sugarcane fermentation. Rich in organic matter, it is known that the vinasse has the potential to be used as a source of nutrients for plants as well as microorganisms. In this study, the fungi Pleurotus sajor-caju, P. ostreatus, P. albidus and P. flabellatus were cultivated in vinasse and utilised as a complementary diet for Danio rerio fish. The fungi mycelia cultured in vinasse for 15 days were lyophilised and offered to the fishes at a rate of 2% (medium/body weight) for 28 days. P. albidus produced the highest biomass (16.27 g L-1). Bromatological analysis of mycelia showed similar values to commercial rations. Toxicity tests showed that fish survival was 100% and no significant biomass loss was observed, indicating that the tested fungi grown in vinasse showed no toxicity. Our results showed that vinasse is a promising by-product for fungal growth and the mycelia of Pleurotus sp. fungi can be included in the diets of fish as a nutritional supplement.

18.
Artigo em Inglês | MEDLINE | ID: mdl-25965511

RESUMO

Sherds representative of the three Portuguese faience production centers of the 17th century - Lisbon, Coimbra and Vila Nova were studied with the use of mostly non-invasive spectroscopies, namely: ground state diffuse reflectance absorption (GSDR), micro-Raman, Fourier-transform infrared (FT-IR) and proton induced X-ray (PIXE) or X-ray fluorescence emission (XRF). X-ray diffraction (XRD) experiments were also performed. The obtained results evidence a clear similarity in the pastes of the pottery produced Vila Nova and some of the ceramic pastes from Lisbon, in accordance with documental sources that described the use of Lisbon clays by Vila Nova potters, at least since mid 17th century. Quartz and Gehlenite are the main components of the Lisbon's pastes, but differences between the ceramic pastes were detected pointing out to the use of several clay sources. The spectroscopic trend exhibited Coimbra's pottery is remarkably different, Quartz and Diopside being the major components of these pastes, enabling one to well define a pattern for these ceramic bodies. The blue pigment from the Lisbon samples is a cobalt oxide that exists in the silicate glassy matrix, which enables the formation of detectable cobalt silicate microcrystals in most productions of the second half of the 17th century. No micro-Raman cobalt blue signature could be detected in the Vila Nova and Coimbra blue glazes. This is in accordance with the lower kiln temperatures in these two production centers and with Co(2+) ions dispersed in the silicate matrix. In all cases the white glaze is obtained with the use of tin oxide. Hausmannite was detected as the manganese oxide mineral used to produce the purple glaze (wine color "vinoso") in Lisbon.


Assuntos
Cerâmica/química , Cerâmica/história , Estanho/análise , Corantes/análise , Corantes/história , História do Século XVII , Pintura/análise , Pintura/história , Portugal , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Estanho/história , Difração de Raios X
19.
Neuroscience ; 294: 29-37, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25766938

RESUMO

Proteomic profiles of the thalamus and the correlation between the rats' performance on a spatial learning task and differential protein expression were assessed in the thiamine deficiency (TD) rat model of Wernicke-Korsakoff syndrome. Two-dimensional gel-electrophoresis detected 320 spots and a significant increase or decrease in seven proteins. Four proteins were correlated to rat behavioral performance in the Morris Water Maze. One of the four proteins was identified by mass spectrometry as Voltage-Dependent Anion Channels (VDACs). The association of VDAC is evident in trials in which the rats' performance was worst, in which the VDAC protein was reduced, as confirmed by Western blot. No difference was observed on the mRNA of Vdac genes, indicating that the decreased VDAC expression may be related to a post-transcriptional process. The results show that TD neurodegeneration involves changes in thalamic proteins and suggest that VDAC protein activity might play an important role in an initial stage of the spatial learning process.


Assuntos
Transtornos Cognitivos/metabolismo , Síndrome de Korsakoff/metabolismo , Aprendizagem/fisiologia , Tálamo/metabolismo , Canais de Ânion Dependentes de Voltagem/metabolismo , Animais , Modelos Animais de Doenças , Síndrome de Korsakoff/genética , Masculino , Proteômica/métodos , Ratos Wistar , Percepção Espacial , Deficiência de Tiamina/genética
20.
Arq. bras. med. vet. zootec ; 67(1): 62-70, 2/2015. tab, graf
Artigo em Português | LILACS | ID: lil-741109

RESUMO

O objetivo geral deste trabalho foi analisar o efeito da radiação vermelha de baixa intensidade sobre alguns parâmetros cinéticos do espermatozoide canino criopreservado. Ejaculados de oito cães adultos foram centrifugados, rediluídos em meio tris-gema de ovo com 6% de glicerol, e, posteriormente, fracionados em: T1: incidência de radiação vermelha (660 NM) (Fisioled - Mmoptics - 100mW) por 60 segundos, antes do resfriamento e após a descongelação; T2: incidência somente antes do resfriamento; T3: incidência somente após a descongelação; e T4: sem incidência. Após a descongelação, as amostras foram submetidas ao TTR utilizando-se Sperm Class Analyzer(r). No TTR0, TTR60 e TTR90, não houve diferença entre as variáveis analisadas pelo CASA. Somente no TTR30 os efeitos da incidência da radiação vermelha foram evidentes e significativos em T1 e T2; T1 resultou em baixa MT (12,5 + 10,6%) e T2 determinou o melhor resultado de MT 40,3 + 26,1%. De forma similar T1 apresentou maior número de espermatozoides estáticos (77,5±28,9%) em relação ao T2 (50,6±28%). Concluiu-se que a dupla incidência de radiação vermelha de baixa intensidade antes do resfriamento e após a descongelação teve efeito deletério sobre a motilidade do espermatozoide canino, expressa principalmente aos 30 minutos após descongelação.


The aim of this study was to analyze the effect of low intensity red light on some kinetic parameters of cryopreserved canine sperm. Ejaculates from 08 adult dogs were centrifuged, diluted in Tris-egg yolk with 6% glycerol, and subsequently separated into: T1: incidence of red light (660 nm) (Fisioled -MMOptics - 100mW) for 60 seconds before the cooling and after thawing, T2: just before cooling, T3: only after thawing, and T4: no incidence. After thawing the samples were subjected to TTR using Sperm analyzer(r). In TTR0, TTR60 and TTR90 there were no differences between the variables analyzed by CASA. Only in TTR30 the effects of the incidence of red light were visible and significant in T1 and T2. T1 resulted in low MT (12.5 ±10.6%) and T2 determined the best result of MT 26.1%±40.3. Similarly T1 showed a higher number of static spermatozoa (77.5±28.9%) compared to T2 (50.6±28%). We concluded that the double incidence of low intensity red light, before cooling and after thawing, had a deleterious effect on canine sperm motility expressed at 30 minutes after thawing.


Assuntos
Animais , Masculino , Cães , Efeitos da Radiação , Preservação do Sêmen/estatística & dados numéricos , Preservação do Sêmen/veterinária , Análise do Sêmen/métodos
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