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1.
Eur Arch Paediatr Dent ; 22(2): 273-282, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32862363

RESUMO

PURPOSE: To evaluate the perception of parents and children and the impact of molar and incisor hypomineralization (MIH) on the oral health-related quality of life (OHRQoL). METHODS: A cross-sectional study was conducted with a group of 253 children aged 6-12 years presenting MIH and their parents or guardians who initially answered an interview containing socioeconomic and demographic questions as well as the Parental-Caregiver's Perceptions Questionnaire (P-CPQ). The children answered the Child Perceptions Questionnaire (CPQ8-10) and Child Perceptions Questionnaire (CPQ11-14) and the clinical evaluation of MIH was performed. Poisson regression with robust variance was used in the data analysis. RESULTS: The parent's perception showed that the impact felt by the children regarding caries leads to a higher oral symptom impact, functional limitation, emotional well-being and total PCPQ score domains, as well. For children with severe MIH, a higher prevalence of impact was felt regarding the functional limitation and emotional well-being. For CPQ8-10, the oral symptoms domain presented the highest mean score, while CPQ11-14 showed the functional limitations domain and P-CPQ the emotional well-being domain. CONCLUSION: Considering the perception of parents or guardians, it was concluded that MIH promotes a negative impact on the OHRQoL. MIH had no significant impact on OHRQoL according to children's perceptions.


Assuntos
Hipoplasia do Esmalte Dentário , Qualidade de Vida , Criança , Estudos Transversais , Humanos , Incisivo , Dente Molar , Saúde Bucal , Pais , Percepção , Prevalência
2.
Neotrop Entomol ; 48(4): 614-627, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30758777

RESUMO

Feltia llanoi (Köhler, 1953) stat. rev. and its hitherto senior subjective synonym Feltia brachystria (Hampson, 1903) are two species of noctuid moths with unusual broadly bipectinate antenna and restricted distribution in central eastern Argentina, southern Brazil, and Uruguay. Examination of the type of specimens and further material from several collections indicates that these names are not synonyms, but valid species, and reveal the occurrence of F. llanoistat. rev. in Brazil. Therefore, F. llanoistat. rev. and F. brachystria are redescribed and the former name is reinstated to species, including taxonomic comments, illustration of some characters of taxonomic importance, and of structures of the male and female genitalia. The species are compared with similar-looking and supposedly closely related species, such as F. chilensis (Hampson, 1903), F. carolia (Schaus, 1929), and F. gypaetina (Guenée, 1852). Additionally, in order to stabilize nomenclature, a lectotype for F. llanoistat. rev. is designated, and Agrotis daguerrei Köhler, 1961 is here recognized as a junior subjective synonym of F. llanoistat. rev. (syn. nov.).


Assuntos
Distribuição Animal , Mariposas/anatomia & histologia , Mariposas/classificação , Animais , Brasil , Feminino , Genitália Feminina , Genitália Masculina , Masculino , Análise Espaço-Temporal
3.
Neotrop Entomol ; 48(1): 98-110, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29873032

RESUMO

Feltia submontana (Köhler, 1961) is redescribed based on specimens from Northwestern Argentina and Central and Southeastern Brazil. Taxonomic comments, photographs of the adults, characters of taxonomic importance, and illustrations of structures of the labial palpus, legs, and male and female genitalia are provided. The species is compared with similar-looking and supposedly closely related species, such as F. hispidula (Guenée, 1852) and F. lilacina (Zerny, 1916). The species, originally described for Argentina, is reported for Brazil for the first time. Most Brazilian specimens come from the "Cerrado" but also from Southeastern Atlantic Forests. The life cycle of F. submontana specimens collected in Planaltina, Distrito Federal, Brazil, is described; the species probably has only a single generation per year and imagines are on the wing in the late autumn and early winter months; the last instar prepupa and pupa pass through aestival diapause. The abundance of F. submontana relative to other species of Agrotis Ochsenheimer, 1816, and Feltia Walker, 1856, in the above-cited locality is accessed through 4 years of standardized collecting with light trap; the species is the second most abundant species of these genera in the area, with about one fifth of the captures, second only to A. ipsilon (Hufnagel, 1766), with about two thirds of the captures, and about two times more abundant than F. subterranea (Fabricius, 1794); the latter two are regarded as important pest species in South America.


Assuntos
Mariposas/classificação , Distribuição Animal , Animais , Argentina , Brasil , Feminino , Genitália Feminina , Genitália Masculina , Estágios do Ciclo de Vida , Masculino , Mariposas/anatomia & histologia
4.
Sci Rep ; 8(1): 12595, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30135558

RESUMO

Direct assembling of N-graphene, i.e. nitrogen doped graphene, in a controllable manner was achieved using microwave plasmas at atmospheric pressure conditions. The synthesis is accomplished via a single step using ethanol and ammonia as carbon and nitrogen precursors. Tailoring of the high-energy density plasma environment results in a selective synthesis of N-graphene (~0.4% doping level) in a narrow range of externally controlled operational conditions, i.e. precursor and background gas fluxes, plasma reactor design and microwave power. Applying infrared (IR) and ultraviolet (UV) irradiation to the flow of free-standing sheets in the post-plasma zone carries out changes in the percentage of sp2, the N doping type and the oxygen functionalities. X-ray photoelectron spectroscopy (XPS) revealed the relative extension of the graphene sheets π-system and the type of nitrogen chemical functions present in the lattice structure. Scanning Electron microscopy (SEM), Transmission Electron microscopy (TEM) and Raman spectroscopy were applied to determine morphological and structural characteristics of the sheets. Optical emission and FT-IR spectroscopy were applied for characterization of the high-energy density plasma environment and outlet gas stream. Electrochemical measurements were also performed to elucidate the electrochemical behavior of NG for supercapacitor applications.

5.
Phys Chem Chem Phys ; 20(20): 13810-13824, 2018 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-29745408

RESUMO

An experimental and theoretical study on microwave (2.45 GHz) plasma enabled assembly of carbon nanostructures, such as multilayer graphene sheets and nanoparticles, was performed. The carbon nanostructures were fabricated at different Ar-CH4 gas mixture composition and flows at atmospheric pressure conditions. The synthesis method is based on decomposition of the carbon-containing precursor (CH4) in the "hot" microwave plasma environment into carbon atoms and molecules, which are further converted into solid carbon nuclei in the "colder" plasma zones. By tailoring of the plasma environment, a controlled synthesis of graphene sheets and diamond-like nanoparticles was achieved. Selective synthesis of graphene flakes was achieved at a microwave power of 1 kW, Ar and methane flow rates of 600 sccm and 2 sccm respectively, while the predominant synthesis of diamond-like nanoparticles was obtained at the same power, but with higher flow rates, i.e. 1000 and 7.5 sccm, respectively. Optical emission spectroscopy was applied to detect the plasma emission related to carbon species from the 'hot' plasma zone and to determine the main plasma parameters. Raman spectroscopy and scanning electron microscopy have been applied to characterize the synthesized nanostructures. A previously developed theoretical model was further updated and employed to understand the mechanism of CH4 decomposition and formation of the main building units, i.e. C and C2, of the carbon nanostructures. An insight into the physical chemistry of carbon nanostructure formation in a high energy density microwave plasma environment is presented.

6.
Neotrop Entomol ; 47(2): 211-255, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28971353

RESUMO

The genus Praepedaliodes Forster, 1964, the only representative of the mega-diverse mostly Andean Pedaliodes complex lineage in the Brazilian Atlantic Forest, is revised. Prior to this study, four species were known, P. phanias (Hewitson, 1862), P. granulata (Butler, 1868), P. amussis (Thieme, 1905) and P. exul (Thieme, 1905). Here, a further six are described, all from SE Brazil, expanding to 10 the number of species in this genus. Lectotypes are designated for P. phanias, P. granulata and P. amussis. The genus is most diverse in the Serra da Mantiqueira (São Paulo, Rio de Janeiro, Minas Gerais) and in the Serra Geral (Paraná, Santa Catarina) with seven species occurring in both ranges. Praepedaliodes phanias is the most widespread species and the only one found in the western part of the Atlantic Forest; only this species and P. duartei Dias, Dolibaina & Pyrcz n. sp. occurring to near sea level. Other species, P. zaccae Dolibaina, Dias & Pyrcz n. sp., P. francinii Freitas & Pyrcz n. sp., P. sequeirae Pyrcz, Dias & Dolbaina n. sp., P. landryi Pyrcz & Freitas n. sp. and P. pawlaki Pyrcz & Boyer n. sp. are strictly montane and the highest species richness is reached at 1400-1800 m. One species, P. sequeirae n. sp., is a narrow endemic found only at timberline in the Agulhas Negras massif above 2300 m. Immature stages are described for two species, P. phanias and P. landryi n. sp. Molecular data (barcode region of cytochrome oxidase, subunit I) and adult morphology, including male and female genitalia, support the genus as monophyletic, belonging to a predominantly Andean clade of the Pedaliodes Butler, 1867 complex. Morphological evidences, in particular female genitalia comparative analysis, indicate the genera Physcopedaliodes Forster, 1964 and Panyapedaliodes Forster, 1964 as possibly the closest relatives to Praepedaliodes. Molecular data are inconclusive in this respect.


Assuntos
Borboletas/anatomia & histologia , Borboletas/classificação , Animais , Brasil , Feminino , Florestas , Masculino , Filogenia
7.
Neotrop Entomol ; 45(5): 524-536, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27255765

RESUMO

Six species of Adelpha Hübner from Balneário Barra do Sul (Santa Catarina) and Morretes (Paraná) were collected as eggs or larvae and reared in captivity, aiming to provide descriptions and photography of the immature stages and imagoes. The species studied were Adelpha radiata radiata Fruhstorfer; Adelpha serpa serpa (Boisduval); Adelpha plesaure plesaure Hübner; Adelpha thesprotia (C. Felder & R. Felder); Adelpha lycorias lycorias (Godart); and Adelpha capucinus velia (C. Felder & R. Felder). Two new records of host plants were provided, Tapirira guianensis Aubl. for A. radiata radiata and Heteropterys for A. capucinus velia. This study provides a summary of host plants and the seasonality of occurrence of immature stages of these species. Data were organized in photographic plates that could be useful for the identification process.


Assuntos
Borboletas , Animais , Brasil , Borboletas/anatomia & histologia , Borboletas/crescimento & desenvolvimento , Florestas , Larva
8.
Reprod Domest Anim ; 47(2): 196-202, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21806689

RESUMO

The function of prion-like protein Doppel was suggested to be related to male fertility. In this study, the importance of ovine Doppel polypeptide on spermatozoa capacitation and fertilization was evaluated. After refolding, recombinant Doppel (rDpl) was supplemented with different concentrations (40, 80 or 190 ng/ml) to ovine spermatozoa during the capacitation process. In experiment 1, post-thawed ovine spermatozoa were incubated with different concentrations of rDpl during 1 h for swim-up, and changes in sperm motility, concentration, vigour, viability and capacitation were monitored (10 replicates). In experiment 2, the fertilization ability of post-swim-up spermatozoa incubated as above was tested through heterologous fertilization of bovine in vitro matured oocytes (n = 423, three replicates). Regardless of dosage, rDpl improved (p ≤ 0.03) spermatozoa viability. Sperm individual motility and vigour were the highest (p ≤ 0.04) for the group receiving 190 ng/ml rDpl. Sperm supplemented with the highest doses of rDpl achieved higher (p = 0.02) fertilization rates (56.0 ± 3.0%) than control (39.1 ± 2.2%) and 40 ng/ml rDpl (39.8 ± 2.7%). Preliminary data suggest that Doppel protein may enhance in vitro spermatozoa fertilizing ability.


Assuntos
Proteínas Ligadas por GPI/metabolismo , Príons/metabolismo , Carneiro Doméstico/fisiologia , Espermatozoides/fisiologia , Animais , Clonagem Molecular , Fertilização in vitro/veterinária , Proteínas Ligadas por GPI/genética , Regulação da Expressão Gênica/fisiologia , Masculino , Príons/genética , Capacitação Espermática/fisiologia , Motilidade dos Espermatozoides/fisiologia
10.
Br Poult Sci ; 45(5): 648-56, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15623219

RESUMO

(1) Cellulases and xylanases display a modular architecture that comprises a catalytic module linked to one or more non-catalytic carbohydrate-binding modules (CBMs). On the basis of primary structure similarity, CBMs have been classified into more than 30 different families. These non-catalytic modules mediate a prolonged and intimate contact of the enzyme with the target substrate, eliciting efficient hydrolysis of the insoluble polysaccharides. (2) Xylanases are very effective in improving the nutritive value of wheat- or rye-based diets for broiler chicks although the role of non-catalytic CBMs in the function of exogenous modular xylanases in vivo remains to be determined. (3) A study was undertaken to investigate the importance of a family 6 CBM in the function of recombinant derivatives of xylanase 11A (Xyn11A) of Clostridium thermocellum used to supplement cereal-based diets for poultry. (4) The data show that birds fed on a wheat-based diet supplemented with the modular xylanase display an increased final body weight when compared with birds receiving Xyn11A catalytic module or birds receiving the enzyme mixture Roxazyme G. (5) Interestingly, the modular xylanase was truncated and transformed into its single domain counterpart on the duodenum of birds fed on the wheat-based diets, most possibly due to the action of pancreatic proteases. (6) Together the data point to the importance of CBMs in the function of feed xylanases and suggest, that in chicken fed on wheat-based diets, the main sites for exogenous enzymes action might be the gastrointestinal (GI) compartments preceding the duodenum, most probably the crop.


Assuntos
Metabolismo dos Carboidratos , Galinhas , Dieta , Grão Comestível , Endo-1,4-beta-Xilanases/administração & dosagem , Endo-1,4-beta-Xilanases/química , Animais , Sítios de Ligação , Clostridium thermocellum/enzimologia , Suplementos Nutricionais , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática , Glicosídeo Hidrolases/administração & dosagem , Masculino , Complexos Multienzimáticos/administração & dosagem , Proteínas Recombinantes , Secale , Triticum , Aumento de Peso
11.
Biochemistry ; 40(31): 9167-76, 2001 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-11478884

RESUMO

The majority of plant cell wall hydrolases are modular enzymes which, in addition to a catalytic module, possess one or more carbohydrate-binding modules (CBMs). These carbohydrate-active enzymes and their constituent modules have been classified into a number of families based upon amino acid sequence similarity. The Clostridium thermocellum xylanase, Xyn10B, contains two CBMs that belong to family 22 (CBM22). The crystal structure of the C-terminal CBM22 (CBM22-2) was determined in a previous study [Charnock, S. J., et al. (2000) Biochemistry 39, 5013--5021] and revealed a surface cleft which presents several conserved residues that are implicated in ligand binding. These amino acids have been substituted and the structure and biochemical properties of the mutants analyzed. The data show that R25A, W53A, Y103A, Y136A, and E138A exhibit greatly reduced affinity for xylotetraose relative to that of the wild-type protein. Conversely, mutations Y103F and Y136F have little effect on ligand binding. Using thermodynamic, X-ray, and NMR measurements on the mutants, we show that the cleft of CBM22-2 does indeed form the ligand-binding site. Trp 53 and Tyr 103 most likely participate in hydrophobic stacking interactions with the ligand, while Glu 138 makes one or more important hydrogen bonds with the tetrasaccharide. Although Arg 25 and Tyr 136 are likely to form hydrogen bonds with the ligand, they are also shown to play a critical role in maintaining the structural integrity of the binding cleft.


Assuntos
Aminoácidos/química , Aminoácidos/metabolismo , Metabolismo dos Carboidratos , Clostridium/enzimologia , Xilosidases/química , Xilosidases/metabolismo , Motivos de Aminoácidos/genética , Substituição de Aminoácidos/genética , Aminoácidos/genética , Sítios de Ligação/genética , Clostridium/genética , Sequência Conservada , Cristalografia por Raios X , Ligantes , Mutagênese Sítio-Dirigida , Ressonância Magnética Nuclear Biomolecular , Oligossacarídeos/metabolismo , Ligação Proteica/genética , Termodinâmica , Triptofano/metabolismo , Xilano Endo-1,3-beta-Xilosidase , Xilanos/metabolismo , Xilosidases/genética
12.
Arch Biochem Biophys ; 286(1): 159-63, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1910283

RESUMO

Pseudomonas aeruginosa is an obligate respirer which can utilize nitrate as a terminal electron acceptor under anaerobic conditions (denitrification). Immediate, transient regulation of nitrate respiration is mediated by oxygen through the inhibition of nitrate uptake. In order to gain an understanding of the bioenergetics of nitrate transport and its regulation by oxygen, the effects of various metabolic inhibitors on the uptake process and on oxygen regulation were investigated. Nitrate uptake was stimulated by the protonophores carbonyl cyanide m-chlorophenylhydrazone and 2,4-dinitrophenol, indicating that nitrate uptake is not strictly energized by, but may be affected by the proton motive force. Oxygen regulation of nitrate uptake might in part be through redox-sensitive thiol groups since N-ethylmaleimide at high concentrations decreased the rate of nitrate transport. Cells grown with tungstate (deficient in nitrate reductase activity) and azide-treated cells transported nitrate at significantly lower rates than untreated cells, indicating that physiological rates of nitrate transport are dependent on nitrate reduction. Furthermore, tungstate grown cells transported nitrate only in the presence of nitrite, lending support to the nitrate/nitrite antiport model for transport. Oxygen regulation of nitrate transport was relieved (10% that of typical anaerobic rates) by the cytochrome oxygen reductase inhibitors carbon monoxide and cyanide.


Assuntos
Nitratos/metabolismo , Oxigênio/farmacologia , Pseudomonas aeruginosa/metabolismo , 2,4-Dinitrofenol , Aerobiose , Anaerobiose , Transporte Biológico/efeitos dos fármacos , Monóxido de Carbono/farmacologia , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Dinitrofenóis/farmacologia , Cinética , Pseudomonas aeruginosa/efeitos dos fármacos
13.
J Biol Chem ; 265(30): 18095-7, 1990 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-2170403

RESUMO

Anaerobic nitrate respiration is regulated by oxygen at the level of nitrate transport; however, the mechanism of O2 inhibition is unknown. Potentially, oxygen could inhibit directly by causing conformational changes in the porter system or indirectly through diversion of electron flow from the nitrate reductase complex to oxygen reduction. Inhibition due to electron diversion implies that nitrate reduction is required for nitrate transport. In this regard, nitrate uptake and its regulation by oxygen were studied in mutants of Escherichia coli (strain AN386) deficient in cytochrome d (RG98), cytochrome o (RG101), and a mutant deficient in both cytochrome d and cytochrome o (RG99). Respiratory nitrate uptake in RG99 was highly resistant to the effects of oxygen supporting the indirect mechanism of electron diversion in oxygen regulation. Nitrate transport in RG98 and RG101 is highly sensitive to oxygen; these mutants exhibited 81 and 85% inhibition, respectively, which is similar to inhibition in the wild type. These results indicate that during nitrate respiration, O2 inhibits transport by limiting the supply of electrons to the nitrate reductase complex.


Assuntos
Grupo dos Citocromos b , Proteínas de Escherichia coli , Escherichia coli/fisiologia , Nitratos/metabolismo , Oxigênio/fisiologia , Aerobiose , Transporte Biológico , Grupo dos Citocromos d , Citocromos/fisiologia , Transporte de Elétrons , Metabolismo Energético , Nitrato Redutase , Nitrato Redutases/metabolismo
14.
Biochem Biophys Res Commun ; 166(1): 424-30, 1990 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-2154208

RESUMO

Nitrate transport and its regulation by oxygen was studied in denitrifying halophilic Pseudomonas stutzeri, strain Zobell, and a Tn-5 transposon nitrite reductase mutant of this organism. The rate of nitrate transport was found to be 130 nanomoles nitrate min-1 mg protein-1 and 150 nanomoles nitrate min-1 mg protein-1 in the wildtype and the nitrite reductase mutant respectively as compared to 26.4 nanomoles nitrate min-1 mg protein-1 in a non-halophilic Pseudomonas stutzeri. Asparagine was found to be the best energy source for nitrate uptake. The ratio of nitrate import to nitrite export was established by measuring extracellular nitrate and nitrite concentrations using HPLC/UV analysis. There was a 1.3:1 (NO3-/NO2-) exchange. High concentrations of nitrate during growth was found to have a negative effect on nitrite metabolism. Oxygen exerted an inhibitory effect on nitrate uptake which was reversible and more pronounced in cells grown on low concentrations of nitrate compared to cells grown at high concentrations of nitrate.


Assuntos
Nitratos/metabolismo , Pseudomonas/metabolismo , Aerobiose , Transporte Biológico/efeitos dos fármacos , Elementos de DNA Transponíveis , Temperatura Alta , Cinética , Mutação , Nitrito Redutases/genética , Nitritos/metabolismo , Oxigênio/farmacologia , Pseudomonas/efeitos dos fármacos , Pseudomonas/genética , Especificidade da Espécie
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