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1.
ACS Omega ; 8(44): 41295-41301, 2023 Nov 07.
Article in English | MEDLINE | ID: mdl-37969988

ABSTRACT

Nanostructured materials have emerged as valuable tools for the advancement of novel electrocatalysts. Among them, three-dimensional metal oxides have gained significant attention due to their excellent conductivity, cost-effectiveness, and unique design. This study focuses on the synthesis of cotton-like three-dimensional antimony oxychloride (Sb4O5Cl2) structures through a straightforward precipitation method. The nanostructures exhibit immense potential for sensing applications. Electrochemical characterization reveals that the Sb4O5Cl2 heterostructure demonstrates a remarkable double-layer capacitance of 662 F/cm2, accompanied by excellent cyclic stability. The sensor's performance was tested for the detection of ammonium hydroxide (HA) in NaCl solution, yielding sensitivities ranging from 0.95 to 0.140 mA mM-1 cm-2 and a detection limit of 4.54 µM within a wide detection range of 0.3-250 mM. The sensor device possesses a distinctive cotton-like structure and is synthesized through a simple and cost-effective route.

2.
Curr Microbiol ; 78(8): 3218-3229, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34213615

ABSTRACT

The presence of endophytes promotes the biosynthesis of secondary plant metabolites. In this study, endophytic fungi were isolated from Schinus terebinthifolius to investigate their diversity and antimicrobial activity. A total of 272 endophytic fungi was obtained. These belonged to nine different genera: Alternaria, Colletotrichum, Diaporthe, Epicoccum, Fusarium, Pestalotiopsis, Phyllosticta, Xylaria, and Cryptococcus. Notably, Diaporthe foliorum was introduced as a new species, with accompanying morphological descriptions, illustrations, and a multigene phylogenetic analysis (using ITS, TEF1, TUB, HIS, and CAL). Among the 26 fungal morphotypes evaluated for antimicrobial activity, five strains had inhibitory effects against pathogenic microorganisms. Xylaria allantoidea CMRP1424 extracts showed antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. Diaporthe terebinthifolii CMRP1430 and CMRP1436 showed antimicrobial activity against E. coli, P. aeruginosa, S. aureus, and C. albicans. Meanwhile, D. foliorum CMRP1321 and D. malorum CMRP1438 extracts inhibited C. albicans alone. Three classes of chemical compounds were identified in D. foliorum CMRP1438 extracts: ferric chloride, potassium hydroxide, and vanillin-sulfuric acid. In conclusion, the endophytic isolates were able to produce bioactive agents with pharmaceutical potential as antibacterial and antifungal agents. As such, they may provide fresh leads in the search for new, biological sources of drug therapies.


Subject(s)
Anacardiaceae , Anti-Infective Agents , Anti-Infective Agents/pharmacology , Ascomycota , Endophytes/genetics , Escherichia coli , Fungi , Microbial Sensitivity Tests , Phylogeny , Staphylococcus aureus
3.
Molecules ; 26(8)2021 Apr 13.
Article in English | MEDLINE | ID: mdl-33924397

ABSTRACT

Over the last two decades, oxide nanostructures have been continuously evaluated and used in many technological applications. The advancement of the controlled synthesis approach to design desired morphology is a fundamental key to the discipline of material science and nanotechnology. These nanostructures can be prepared via different physical and chemical methods; however, a green and ecofriendly synthesis approach is a promising way to produce these nanostructures with desired properties with less risk of hazardous chemicals. In this regard, ZnO and TiO2 nanostructures are prominent candidates for various applications. Moreover, they are more efficient, non-toxic, and cost-effective. This review mainly focuses on the recent state-of-the-art advancements in the green synthesis approach for ZnO and TiO2 nanostructures and their applications. The first section summarizes the green synthesis approach to synthesize ZnO and TiO2 nanostructures via different routes such as solvothermal, hydrothermal, co-precipitation, and sol-gel using biological systems that are based on the principles of green chemistry. The second section demonstrates the application of ZnO and TiO2 nanostructures. The review also discusses the problems and future perspectives of green synthesis methods and the related issues posed and overlooked by the scientific community on the green approach to nanostructure oxides.

4.
Mol Biochem Parasitol ; 221: 1-9, 2018 04.
Article in English | MEDLINE | ID: mdl-29409763

ABSTRACT

In the protozoan parasite Trypanosoma cruzi - the causative agent of Chagas disease - gene expression control is mainly post-transcriptional, where RNA-binding proteins (RBPs) play a central role, by controlling mRNA stability, distribution and translation. A large variety of RBPs are encoded in the T. cruzi genome, including the CCCH-type zinc finger (CCCH ZnF) protein family, which is characterized by the presence of the C-X7/8-C-X5-C-X3-H (CCCH) motif. In the related parasite T. brucei, CCCH ZnF proteins have been shown to control key differentiation steps in the parasite's life cycle. However, little is known about the CCCH ZnF proteins in T. cruzi. We have worked on the generation of T. cruzi mutants for CCCH ZnF proteins in an effort to shed light on the functions of these proteins in this parasite. Here, we characterize the expression and function of the CCCH ZnF protein TcZC3H31 of T. cruzi. TcZC3H31 is almost exclusively expressed in epimastigotes and metacyclic trypomastigotes, the parasite forms found in the invertebrate host. Importantly, we show that the epimastigote form of the T. cruzi knockout for the TcZC3H31 gene (TcZC3H31 KO) is incapable, both in vitro and in vivo (in infected triatomine insects), to differentiate into the metacyclic trypomastigote form, which is responsible for infection transmission from vectors to humans. The epimastigote forms recovered from the excreta of insects infected with TcZC3H31 KO parasites do not have the typical epimastigote morphology, suggesting that parasites are arrested in a mid-differentiation step. Also, epimastigotes overexpressing TcZC3H31 differentiate into metacyclics more efficiently than wild-type epimastigotes, in vitro. These data suggest that TcZC3H31 is an essential positive regulator of T. cruzi differentiation into the human-infective metacyclic form.


Subject(s)
Protozoan Proteins/metabolism , RNA-Binding Proteins/metabolism , Trypanosoma cruzi/cytology , Trypanosoma cruzi/growth & development , Zinc Fingers , Animals , Gene Expression Profiling , Gene Knockout Techniques , Insecta , Protozoan Proteins/genetics , RNA-Binding Proteins/genetics , Trypanosoma cruzi/genetics
5.
Dalton Trans ; 44(40): 17673-85, 2015 Oct 28.
Article in English | MEDLINE | ID: mdl-26394903

ABSTRACT

Europium doped silver tungstates α-Ag2-3xEuxWO4 (x = 0, 0.0025, 0.005, 0.0075 and 0.01 mol) were synthesized by the coprecipitation method at 90 °C for 30 minutes. These crystals were structurally characterized by means of X-ray diffraction (XRD), Rietveld refinement, and micro-Raman (MR) and Fourier transformed infrared (FT-IR) spectroscopies. Field emission scanning electron microscopy (FE-SEM) images were employed to observe the shape of the crystals. The optical properties were investigated by ultraviolet-visible (UV-vis) absorption and photoluminescence (PL) measurements. The XRD pattern indicated structural organization at a long range for all undoped and Eu-doped samples, while MR and FT-IR revealed that the presence of the Eu(3+) ions favors the structural organization at a short range. The Rietveld refinement showed that all the crystals are monophasic with an orthorhombic structure and the Pn2[combining macron]n space group. The refined lattice parameters and atomic positions were employed to model the WO6 and AgOn (n = 2, 4, 6 and 7) polyhedra in the unit cell. FE-SEM analysis revealed nanorod-like microcrystals with growth of metallic silver on the surface. Further, the UV-vis absorption spectra indicated the existence of intermediary energy levels within the band gap. PL spectra showed a broad band related to the [WO6] group and characteristic narrow peaks due to the f-f transitions of Eu(3+) as a result of efficient energy transfer from the matrix. Also, the emission line shape transitions from (5)D0 to (7)FJ (J = 0-4) levels of the Eu(3+) were noticed. Among the samples, the most intense photoluminescence results were observed for the α-Ag2-3xEuxWO4 (x = 0.0075) sample. Lifetime decays support that the Eu(3+) ions occupy at least two crystallographic sites. CIE coordinates confirmed the colors of the emission spectra which classify this material as a potential phosphor in the visible range.

6.
An. Acad. Nac. Med ; 155(1): 47-50, jan.-mar. 1995. ilus
Article in Portuguese | LILACS | ID: lil-186142

ABSTRACT

Os autores fazem uma revisao literária da S.M.R. enfatizando aspectos da etiopatogenia, diagnóstico e tratamento. Ilustram com três casos clínicos sendo um tratado com clofazimina.


Subject(s)
Humans , Male , Adult , Melkersson-Rosenthal Syndrome/pathology , Tongue, Fissured
7.
Open educational resource in Portuguese | CVSP - Brazil | ID: una-4658

ABSTRACT

Este estudo foi realizado a partir de uma revisão no período entre 1991 e 2010 nas bases de dados Bireme e Lilacs, visando agregar evidências para nortear o desenvolvimento de um projeto de intervenção em saúde bucal, indicando novos rumos à promoção de saúde bucal dos escolares. O material selecionado para o trabalho foi organizado de modo a identificar categorias de atuação programática na área da saúde bucal a fim de se criar um projeto de intervenção na Escola Municipal Prof. Pedro Alcântara Ferreira em Cabo Verde, MG. A proposta de educação em saúde bucal para escolares é uma estratégia para mudar o panorama nacional da saúde bucal, afinal os hábitos construídos durante a infância perduram por toda a vida. A cárie dentária e a doença periodontal são os males que mais acometem a cavidade bucal, sendo a cárie o mais comum em crianças. A determinação social da cárie dental, relacionada aos aspectos econômicos e comportamentais, vem sendo enfatizada em alguns estudos. Cabe à ESB criar meios de interagir com a comunidade para elaborar planos de ação visando amenizar os males que afligem a população.


Subject(s)
Oral Health , National Health Strategies , Health Education, Dental , Health Promotion
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