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1.
Oper Dent ; 48(4): 404-415, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37302142

RESUMO

The effect of annual at-home bleaching on the color, translucency, and whiteness properties of computer-aided design and computer-aided manufacturing (CAD-CAM) monolithic materials requires investigation. The aim of the present in vitro study was to evaluate the effect of simulated annual at-home bleaching (consisting of daily applications for 10 hours a day for 14 days), for up to 3 years, on susceptibility to staining (ΔE00), translucency (ΔTP00), and whiteness (ΔWID) variations and on topography of CAD-CAM monolithic materials. Disks from the Lava Ultimate (LU), Vita Enamic (VE), IPS Empress CAD (EMP), and IPS e.max CAD (EMAX) were allocated as follows: 1) nonbleached or 2) bleached with 10% carbamide peroxide. After reading the CIE L*a*b* coordinates at baseline (R0), specimens were bleached or not and subsequently immersed for a 1-year simulated period in coffee before the next reading (R1). This process was repeated two more times, resulting in R2 and R3. The ΔE00, ΔTP00, and ΔWID between R1, R2, and R3 in relation to R0 were calculated. The surface topography was analyzed by scanning electron microscopy. In general, bleaching increased the staining susceptibility of all materials when compared to the nonbleached groups and that of the LU, VE, and EMAX over the years. Bleaching decreased the translucency of the VE in all years and over the years. When compared to the nonbleached groups, bleaching decreased the whiteness of the LU and EMAX and increased the whiteness of the EMP, while the VE was not affected. In the LU, the whiteness decreased over the years in both treatments, whereas the other materials were not affected with time. All materials showed progressive topographic changes over the years. The simulated annual at-home bleaching with 10% carbamide peroxide adversely affected the topography and the optical and/or colorimetric properties of the evaluated materials.


Assuntos
Cerâmica , Desenho Assistido por Computador , Peróxido de Carbamida , Cor , Teste de Materiais , Propriedades de Superfície , Coloração e Rotulagem , Porcelana Dentária
2.
Oper Dent ; 46(4): 428-437, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624105

RESUMO

Little is known about the impact of bleaching on the optical properties of computer-aided design and computer-aided manufactured (CAD-CAM) monolithic materials. The aim of the present study was to evaluate the effect of one session of in-office bleaching on stain removal, staining susceptibility, translucency, and whiteness variations of CAD-CAM monolithic materials. Disks were fabricated from Lava Ultimate (LU), Vita Enamic (VE), Vita Suprinity (VS), and IPS e.max CAD (IPS). A spectrophotometer was used to register Commission Internationale de l'Eclairage L*a*b* coordinates. For stain removal, 80 specimens from each material were assessed at baseline (R0) and after immersion in deionized water or coffee for 36.5 days followed or not by bleaching with 40% hydrogen peroxide (R1). For staining susceptibility, 80 specimens from each material were analyzed at baseline (R0'), and after having been bleached or not and immersed in deionized water or coffee (R1'). Both analyses were calculated as the color difference (ΔE00) between R1-R0 and R1'-R0', respectively. Differences in translucency (ΔTP00) and whiteness (ΔWID) between R1-R0 and R1'-R0' were also calculated. Data were analyzed by three-way ANOVA and the Games-Howell post hoc test (α=0.05). Clinical significance was based on 50%:50% perceptibility and acceptability thresholds for ΔE00, ΔTP00 and ΔWID, respectively. Surfaces were analyzed by scanning electron microscopy. Coffee increased ΔE00 in LU, VE, and VS, and decreased their translucency and whiteness, whereas the IPS had only its whiteness affected. Bleaching after immersion in coffee decreased ΔE00 in LU and VE, and increased translucency and whiteness of LU, VE, and VS. No effect was observed on IPS. Bleaching before immersion in coffee decreased translucency of LU, but within the acceptable interval, while VE exhibited lower ΔE00, and became more translucent and less dark. Both VS and IPS were not affected. One session of in-office bleaching benefited optical properties of the previously stained LU, VE, and VS, without increasing their susceptibility to staining or adversely providing clinically unacceptable variations in their translucency and whiteness. All variations exhibited by the IPS were below the perceptible threshold.


Assuntos
Cerâmica , Resinas Compostas , Cor , Desenho Assistido por Computador , Porcelana Dentária , Teste de Materiais , Propriedades de Superfície
3.
Neotrop Entomol ; 42(2): 191-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23949754

RESUMO

Cannibalism in the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) (FAW), is a limiting factor in a baculovirus production system. To detect the impact of cannibalism, a two-step bioassay was conducted with different larval ages of FAW fed on two food sources (corn and castor bean leaves) contaminated with the S. frugiperda multiple-embedded nucleopolyhedrovirus. In a first bioassay, the food source affected the cannibalism, being higher for all larval ages tested (5-, 6- and 7-day-old larvae) in larvae fed on corn than on those fed on castor bean leaves. Larval mortality, weight equivalent and larval equivalents (LEs) per hectare decreased as the larval age increased. Larval weight, occlusion bodies (OBs)/larva and total OBs increased when the larval age increased. In a second bioassay, in which only 6- and 7-day-old larvae were used because of the performance in the first bioassay, the cannibalism rates were affected by the interaction between food sources and time of feeding (48 and 72 h), reaching the highest values for 6- and 7-day-old larvae fed on corn leaves for 72 h. Mortality of the FAW was affected by the interaction between food sources, larval age and time of feeding. The lowest mortalities were on 7-day-old larvae when they were fed on castor bean leaves for 48 and 72 h. Larval weight, OBs/larva, total OBs and LEs were affected by the interaction between food sources and larval age. A significant correlation was observed between larval weight and OBs/larva that fed on both food sources, suggesting that larval weight can be used to achieve a concentration to be sprayed in 1 ha.


Assuntos
Baculoviridae , Canibalismo , Lepidópteros/fisiologia , Lepidópteros/virologia , Animais , Alimentos , Larva/virologia , Folhas de Planta
4.
Genome Announc ; 1(1)2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23405345

RESUMO

The canine respiratory coronavirus (CRCoV) K37 strain of the family Coronaviridae, group 2, was isolated in South Korea. Its genome was analyzed by nucleotide sequencing and was determined to have 31,029 bp. The small open reading frames situated between the spike and envelope genes of most of the CRCoV strains (except the CRCoV 4180 strain) were found to encode three nonstructural proteins (4.9 kDa, 2.7 kDa, and 12.8 kDa), while those of bovine coronavirus (BCoV) encode another three nonstructural proteins (4.9 kDa, 4.8 kDa, and 12.7 kDa) and those of a recently isolated bovine respiratory coronavirus (BRCoV) were found to encode only two nonstructural proteins (4.9 kDa and 12.7 kDa). The differences in the genes encoding these small nonstructural proteins may be associated with the emergence of highly similar viruses in different hosts.

5.
Transbound Emerg Dis ; 60(6): 546-51, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22925439

RESUMO

The major policy for eradication of classical swine fever (CSF) in South Korea has focused on the implementation of compulsory vaccination of the susceptible pig population. A vaccine strain of CSF virus, the LOM strain, is used to maintain high herd seroconversion, a practice complementary to the 'stamping-out policy' and restriction of animal movement during disease outbreaks. To survey for the prevalence of CSF in domestic pigs in South Korea over the past 13 years (1999-2011), we tested 4 193 782 and 1 162 645 samples for antibodies and antigens, respectively. Whereas seropositivity for CSF antibodies has been maintained at over 95% in the mainland, in Jeju Island, where no-vaccination has been administered since 1999, seroprevalence has been below 1% during the last 3 years of study (2009-2011). The highest number of outbreaks in South Korea occurred in 2002 and 2003; since then, outbreaks have decreased each year, with the last CSF outbreak recorded in 2009. No outbreaks have occurred during the past 3 years, and a high level of herd immunity has been maintained in the mainland pig population for 8 years; therefore, South Korea could now switch to a no-vaccination policy throughout the country. However, the constant threat of the re-emergence of the disease in the susceptible pig population should be the main consideration in planning and carrying out the last phase of the CSF eradication process.


Assuntos
Vírus da Febre Suína Clássica/isolamento & purificação , Peste Suína Clássica/epidemiologia , Surtos de Doenças/veterinária , Sus scrofa/virologia , Animais , Peste Suína Clássica/prevenção & controle , Peste Suína Clássica/virologia , Vírus da Febre Suína Clássica/imunologia , Surtos de Doenças/prevenção & controle , Prevalência , República da Coreia/epidemiologia , Suínos , Vacinação/veterinária , Vacinas Virais/administração & dosagem
7.
Z Naturforsch C J Biosci ; 56(3-4): 269-72, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11371019

RESUMO

Viscidone (0.5%), vanillin, 3',4'-(methylendioxy)acetophenone, 3-ethoxy-4-methoxybenzaldehyde, cinnamic acid, 3-methoxy-4-hydroxymethyl ester were isolated from propolis of hives from Cuncumen. This is the first report on propolis composition of an arid and a Mediterranean type climate area.


Assuntos
Própole/química , Animais , Abelhas , Benzaldeídos/análise , Chile , Cinamatos/análise , Clima , Pólen/química , Própole/isolamento & purificação
9.
Theor Appl Genet ; 99(3-4): 561-9, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22665190

RESUMO

Resistance to Fusarium head blight (FHB), deoxynivalenol (DON) accumulation, and kernel discoloration (KD) in barley are difficult traits to introgress into elite varieties because current screening methods are laborious and disease levels are strongly influenced by environment. To improve breeding strategies directed toward enhancing these traits, we identified genomic regions containing quantitative trait loci (QTLs) associated with resistance to FHB, DON accumulation, and KD in a breeding population of F(4:7) lines using restriction fragment length polymorphic (RFLP) markers. We evaluated 101 F(4:7) lines, derived from a cross between the cultivar Chevron and an elite breeding line, M69, for each of the traits in three or four environments. We used 94 previously mapped RFLP markers to create a linkage map. Using composite interval mapping, we identified 10, 11, and 4 QTLs associated with resistance to FHB, DON accumulation, and KD, respectively. Markers flanking these QTLs should be useful for introgressing resistance to FHB, DON accumulation, and KD into elite barley cultivars.

10.
Eur J Nucl Med ; 25(10): 1404-11, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9818280

RESUMO

Our aim was to evaluate the use of dual-isotope thallium-201 (Tl) and technetium-99m sestamibi (sestamibi) simultaneous acquisition in brain single-photon emission tomography (SPET) for the differentiation between brain lymphoma and benign central nervous system (CNS) lesions in AIDS patients. Thirty-six consecutive patients with enhancing mass lesions on magnetic resonance (MR) imaging were included in the study. SPET of the brain was performed to obtain simultaneous Tl and sestamibi images. Regions-of-interest were drawn around the lesion and on the contralateral side to calculate uptake ratios. The final diagnosis was reached by pathologic findings in 17 patients and clinical and/or MR follow-up in 19 patients. Of the 36 patients, 11 had brain lymphoma, 1 glioblastoma multiforme, 15 toxoplasmosis and 9 other benign CNS lesions. Correlation between SPET and the final diagnosis revealed in 10 true-positive, 23 true-negative, 1 false-positive and 2 false-negative studies. All patients with toxoplasmosis had negative scans. A patient with a purulent infection had positive scans. Tl and sestamibi scans were concordant in every lesion. The same lesions that took up Tl were also visualized with sestamibi. However, sestamibi scans showed higher lesion-to-normal tissue uptake ratios (3.7 +/- 1.8) compared with those of Tl (2.3 +/- 0.8, P < 0.002). Simultaneous acquisition of Tl and sestamibi can help differentiate CNS lymphoma from benign brain lesions in AIDS patients.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Neoplasias Encefálicas/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Sestamibi , Radioisótopos de Tálio , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Neoplasias Encefálicas/complicações , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada de Emissão de Fóton Único
11.
J NeuroAIDS ; 2(1): 21-42, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-16873183

RESUMO

PURPOSE: Analyze the value of TL-201 (Tl) brain single-photon emission computed tomography (SPECT), to differentiate CNS lymphoma from toxoplasmosis in AIDS patients. MATERIAL AND METHODS: Twenty-four AIDS patients with MR enhancing lesion(s), underwent a brain Tl SPECT. Final diagnosis was established by pathology and clinical/MR follow-up. RESULTS: Nine patients had CNS tumor, 9 toxoplasmosis and 6 other non-tumorous lesions. The sensitivity of T1 to diagnose CNS tumor was 77% and the specificity 93%. Two false negative studies correspond to tumors with significant necrosis. CONCLUSIONS: T1 proved useful for differentiating brain neoplasm from toxoplasmosis. Tumors with significant necrosis, did not show the expected increase in T1 uptake. Determination of T1 uptake ratios help detect tumor with faint tracer uptake.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Linfoma Relacionado a AIDS/diagnóstico , Tomografia Computadorizada de Emissão de Fóton Único , Toxoplasmose/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico por imagem , Infecções Oportunistas Relacionadas com a AIDS/patologia , Adulto , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/diagnóstico por imagem , Neoplasias do Sistema Nervoso Central/patologia , Glioblastoma/diagnóstico , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Humanos , Linfoma Relacionado a AIDS/diagnóstico por imagem , Linfoma Relacionado a AIDS/patologia , Imageamento por Ressonância Magnética , Toxoplasmose/diagnóstico por imagem , Toxoplasmose/patologia
12.
Genome ; 40(2): 249-52, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18464824

RESUMO

The gene Pch2 in 'Cappelle Desprez' is one of two genes found in hexaploid wheat known to confer resistance to eyespot disease. This study was conducted to develop an RFLP linkage map of the distal portion of wheat chromosome 7AL, and to locate and identify markers closely associated with Pch2 for use in marker-assisted selection. Ten loci in addition to Pch2 were mapped on chromosome 7AL, using segregation data from 102 homozygous chromosome 7A recombinant substitution lines derived from 'Chinese Spring' x 'Chinese Spring' ('Cappelle Desprez' 7A). The Pch2 locus was bracketed by two RFLP markers, one 11.0 cM distal to Xcdo347 and the other 18.8 cM proximal to Xwg380. The position of Pch2 on chromosome 7AL is similar to that of Pch1 on chromosome 7DL, suggesting that these resistance genes are homoeoloci. Although no single marker was closely linked to Pch2, simultaneous selection of the flanking RFLP markers Xcdo347 and Xwg380 could be used for selecting Pch2, since double recombination occurred in only 3% of the recombinant population. The use of the flanking RFLP markers to select for Pch2, in combination with previously identified Pch1-linked markers, would facilitate the development of cultivars carrying two genes for resistance to eyespot.

13.
Int J Lepr Other Mycobact Dis ; 58(4): 651-9, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2280115

RESUMO

A 6-year prospective study of 79 household contacts of leprosy cases was made in order to correlate the development of the disease with their specific T-cell immunity, measured by the Mitsuda test, and levels of anti-Mycobacterium leprae antibodies determined in three consecutive observations with the FLA-ABS test. Overall in the contacts, 71.7% were Mitsuda positive and 93.6% showed seropositivity, without regard to their age, sex, or leprosy type of their index case. Households were divided into lower-risk and higher-risk groups according to either the paucibacillary or multibacillary character of their index case. The lower-risk group consisted of 19 contacts of 2 tuberculoid (TT) and 5 indeterminate cases. The higher-risk group was made up of 60 household contacts of 18 active lepromatous (LL) cases. All but two contacts in the former group had a positive Mitsuda reaction; the most common antibody titer was 1:160, with a tendency to stabilize or decrease over time. In the two Mitsuda-negative contacts, increased antibody levels were observed. In the higher-risk group, 61.6% were Mitsuda positive and showed a humoral profile similar to those Mitsuda positive in the lower-risk group. In most of the Mitsuda-negative LL contacts, the antibody levels remained constant or progressively increased, suggesting a high probability of active subclinical infection. This assumption was partially supported by the finding of a new borderline lepromatous (BL) leprosy case in the Mitsuda-negative LL contact group. Nevertheless, the contribution of the close and extensive contact with a multibacilliferous case as a risk factor was difficult to evaluate because of the small size of the sample studied.


Assuntos
Anticorpos Antibacterianos/sangue , Hanseníase/transmissão , Mycobacterium leprae/imunologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Família , Feminino , Seguimentos , Humanos , Antígeno de Mitsuda , Hanseníase/imunologia , Hanseníase Virchowiana/imunologia , Hanseníase Virchowiana/transmissão , Hanseníase Tuberculoide/imunologia , Hanseníase Tuberculoide/transmissão , Masculino , México , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
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