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1.
J Dent Res ; 96(4): 380-387, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28792274

RESUMEN

The Global Burden of Disease 2015 study aims to use all available data of sufficient quality to generate reliable and valid prevalence, incidence, and disability-adjusted life year (DALY) estimates of oral conditions for the period of 1990 to 2015. Since death as a direct result of oral diseases is rare, DALY estimates were based on years lived with disability, which are estimated only on those persons with unmet need for dental care. We used our data to assess progress toward the Federation Dental International, World Health Organization, and International Association for Dental Research's oral health goals of reducing the level of oral diseases and minimizing their impact by 2020. Oral health has not improved in the last 25 y, and oral conditions remained a major public health challenge all over the world in 2015. Due to demographic changes, including population growth and aging, the cumulative burden of oral conditions dramatically increased between 1990 and 2015. The number of people with untreated oral conditions rose from 2.5 billion in 1990 to 3.5 billion in 2015, with a 64% increase in DALYs due to oral conditions throughout the world. Clearly, oral diseases are highly prevalent in the globe, posing a very serious public health challenge to policy makers. Greater efforts and potentially different approaches are needed if the oral health goal of reducing the level of oral diseases and minimizing their impact is to be achieved by 2020. Despite some challenges with current measurement methodologies for oral diseases, measurable specific oral health goals should be developed to advance global public health.


Asunto(s)
Enfermedades Estomatognáticas/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Costo de Enfermedad , Femenino , Salud Global/estadística & datos numéricos , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Prevalencia , Años de Vida Ajustados por Calidad de Vida , Factores de Riesgo , Enfermedades Estomatognáticas/etiología , Adulto Joven
2.
Poult Sci ; 83(1): 109-18, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14761092

RESUMEN

Our objective was to simulate the pink color defect in cooked chicken breast meat with treatment combinations that would induce measurable changes in the conditions of raw meat. In addition, the feasibility of using induced raw meat conditions to develop a logistic regression model for prediction of pinking was studied. Approximately 960 breast fillets from 2 plants with 2 replications were used for inducing in situ conditions with 16 combinations of sodium chloride, sodium tripolyphosphate, sodium erythorbate, and sodium nitrite (present and not present). Muscles in all treatments were subjected to individual injections, followed by tumbling, cooking, and chilling. Raw samples were analyzed for pH, oxidation-reduction potential, and pigment evaluation. Results indicated a significant role of induced in situ conditions of raw meat in the occurrence of pinking. Presence of 1 ppm or more of sodium nitrite in raw meat produced significant pinking of cooked meat. The light muscle color group was least affected and the dark group was most affected by induced pH, oxidation-reduction potential conditions, and metmyoglobin and nitrosopigment content. The predictive ability of the logistic model was more than 90% with nitrosopigment, pH, and reducing conditions being the most important factors. Moreover, validation of the model was confirmed by close association between observed pink samples and those predicted as pink.


Asunto(s)
Conservación de Alimentos/métodos , Conservantes de Alimentos/administración & dosificación , Tecnología de Alimentos/métodos , Carne/normas , Pigmentación , Animales , Pollos , Manipulación de Alimentos/métodos , Conservantes de Alimentos/farmacología , Industria de Procesamiento de Alimentos/normas , Concentración de Iones de Hidrógeno , Modelos Logísticos , Oxidación-Reducción , Polifosfatos/administración & dosificación , Polifosfatos/farmacología , Cloruro de Sodio/administración & dosificación , Cloruro de Sodio/farmacología , Nitrito de Sodio/administración & dosificación , Nitrito de Sodio/farmacología
3.
Poult Sci ; 82(6): 1049-59, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12817464

RESUMEN

The objective of the study was to establish a pink threshold and simulate the pink defect in cooked chicken breast meat with treatment combinations that would induce significant changes in the color of raw and cooked meat. The subjective pink threshold used in judging pink discoloration was established at a* = 3.8. Samples of three color groups (normal, lighter than normal, and darker than normal) of boneless, skinless chicken breast muscles were selected based on instrumental color values. The in situ changes were induced using sodium chloride, sodium tripolyphosphate, sodium erythorbate, and sodium nitrite at two levels: present and not present. Fillets in all treatments were subjected to individual injections, followed by tumbling, cooking, and chilling. Samples were analyzed for color [lightness (L*), red/green axis (a*), yellow/blue axis (b*)] and reflectance spectra. Simulation of the pink defect was achieved in eight of the 16 treatment combinations when sodium nitrite was present and in an additional two treatment combinations when it was absent. Pinking in cooked samples was affected (P < 0.05) by L* of raw meat color. Results confirmed that it was possible to simulate the undesired pinking in cooked chicken white meat when in situ conditions were induced by sodium chloride, sodium tripolyphosphate, and sodium nitrite. The continuation of the simulation study can aid in developing alternative processing methods to eliminate potential pink defects.


Asunto(s)
Culinaria , Carne/normas , Animales , Pollos , Color , Conservantes de Alimentos/administración & dosificación , Conservantes de Alimentos/farmacología , Polifosfatos/administración & dosificación , Polifosfatos/farmacología , Cloruro de Sodio/administración & dosificación , Cloruro de Sodio/farmacología , Nitrito de Sodio/administración & dosificación , Nitrito de Sodio/farmacología
4.
J Virol ; 75(18): 8803-17, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11507225

RESUMEN

The herpes simplex virus type 1 (HSV-1) U(L)34 protein is likely a type II membrane protein that localizes within the nuclear membrane and is required for efficient envelopment of progeny virions at the nuclear envelope, whereas the U(L)31 gene product of HSV-1 is a nuclear matrix-associated phosphoprotein previously shown to interact with U(L)34 protein in HSV-1-infected cell lysates. For these studies, polyclonal antisera directed against purified fusion proteins containing U(L)31 protein fused to glutathione-S-transferase (U(L)31-GST) and U(L)34 protein fused to GST (U(L)34-GST) were demonstrated to specifically recognize the U(L)31 and U(L)34 proteins of approximately 34,000 and 30,000 Da, respectively. The U(L)31 and U(L)34 gene products colocalized in a smooth pattern throughout the nuclear rim of infected cells by 10 h postinfection. U(L)34 protein also accumulated in pleiomorphic cytoplasmic structures at early times and associated with an altered nuclear envelope late in infection. Localization of U(L)31 protein at the nuclear rim required the presence of U(L)34 protein, inasmuch as cells infected with a U(L)34 null mutant virus contained U(L)31 protein primarily in central intranuclear domains separate from the nuclear rim, and to a lesser extent in the cytoplasm. Conversely, localization of U(L)34 protein exclusively at the nuclear rim required the presence of the U(L)31 gene product, inasmuch as U(L)34 protein was detectable at the nuclear rim, in replication compartments, and in the cytoplasm of cells infected with a U(L)31 null virus. When transiently expressed in the absence of other viral factors, U(L)31 protein localized diffusely in the nucleoplasm, whereas U(L)34 protein localized primarily in the cytoplasm and at the nuclear rim. In contrast, coexpression of the U(L)31 and U(L)34 proteins was sufficient to target both proteins exclusively to the nuclear rim. The proteins were also shown to directly interact in vitro in the absence of other viral proteins. In cells infected with a virus lacking the U(S)3-encoded protein kinase, previously shown to phosphorylate the U(L)34 gene product, U(L)31 and U(L)34 proteins colocalized in small punctate areas that accumulated on the nuclear rim. Thus, U(S)3 kinase is required for even distribution of U(L)31 and U(L)34 proteins throughout the nuclear rim. Taken together with the similar phenotypes of the U(L)31 and U(L)34 deletion mutants, these data strongly suggest that the U(L)31 and U(L)34 proteins form a complex that accumulates at the nuclear membrane and plays an important role in nucleocapsid envelopment at the inner nuclear membrane.


Asunto(s)
Herpesvirus Humano 1/fisiología , Proteínas Nucleares/metabolismo , Nucleocápside/metabolismo , Proteínas Virales/metabolismo , Ensamble de Virus/fisiología , Animales , Núcleo Celular/metabolismo , Chlorocebus aethiops , Herpesvirus Humano 1/metabolismo , Humanos , Proteínas Nucleares/genética , Nucleocápside/fisiología , Proteínas Serina-Treonina Quinasas/metabolismo , Células Tumorales Cultivadas , Células Vero , Proteínas Virales/genética
5.
Poult Sci ; 79(8): 1183-8, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10947189

RESUMEN

Marinades containing 0, 0.4, 0.8, and 1.2% apple flavoring were examined to determine the effect of an aqueous apple flavoring on the quality and sensory characteristics of boneless, skinless chicken breast. Marinade pickup and purge loss increased significantly with an increase of apple flavoring in marinades. Incorporation of apple flavoring in the marinades did not affect cook loss of the treatments, except for breast marinated in 1.2% apple flavor, which had higher cook loss. Apple flavoring did not affect final product yield of marinated breast. Shear values were similar for all treatments except marinades with 0.8% apple flavoring, which had lower shear values. Participants detected increases in fruity flavor with an increase of apple flavoring in the marinade. Products containing no apple flavoring were rated as "like moderately" to "like slightly." Products with 0.4% apple flavoring were rated "like slightly," and degree of liking declined to "neither like nor dislike" as apple flavoring increased. Incorporation of acceptable levels of apple flavoring is limited to 0.4%.


Asunto(s)
Pollos , Aromatizantes , Manipulación de Alimentos , Frutas , Fosfatos , Productos Avícolas , Animales , Comportamiento del Consumidor , Gusto
6.
Virology ; 266(2): 310-8, 2000 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-10639317

RESUMEN

The U(L)33 protein is one of six genes (including U(L)6, U(L)15, U(L)17, U(L)28, and U(L)32) required for cleavage of viral concatemeric DNA into unit-length genomes and packaging of the virus genomes into preformed capsids. The U(L)25 gene product is dispensable for cleavage of viral DNA but essential for packaging of DNA into capsids. A polyclonal antiserum was produced against an affinity-purified protein containing the full-length U(L)33 gene product of herpes simplex virus 1 fused to glutathione-S-transferase. A protein of approximate M(r) 19,000 that reacted with the antiserum was detected in immunoblots of herpes simplex virus 1-infected cellular lysates. This protein was not detected in lysates of mock-infected cells or cells infected with a mutant virus containing a stop codon in U(L)33, indicating that the 19,000 M(r) protein is the product of the U(L)33 open reading frame. The U(L)33 gene product was not detected in purified virions or capsids. Accumulation of the U(L)33 protein to detectable levels required viral DNA synthesis, indicating that the protein was regulated as a late gene. Indirect immunofluorescence analysis demonstrated that U(L)33 protein accumulated predominantly within replication compartments in the central domains of infected cell nuclei and within the cytoplasm. Localization of the U(L)33 gene product in replication compartments was maintained in cells infected with a variety of cleavage/packaging mutants.


Asunto(s)
Genes Virales , Herpesvirus Humano 1/genética , Proteínas Virales/genética , Animales , Anticuerpos Antivirales , Línea Celular , Núcleo Celular/virología , Chlorocebus aethiops , ADN Viral/genética , Expresión Génica , Herpesvirus Humano 1/patogenicidad , Herpesvirus Humano 1/fisiología , Humanos , Peso Molecular , Mutación , Células Vero , Proteínas Virales/química , Proteínas Virales/metabolismo , Replicación Viral
7.
Plant Mol Biol ; 25(1): 13-21, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8003693

RESUMEN

A gene encoding a thioredoxin protein was identified in the chloroplast genome of the rhodophyte Porphyra yezoensis. The P. yezoensis trxA gene contains 324 bp and is transcribed into a 0.7 kb messenger RNA. Analysis of the transcription start site demonstrates that canonical chloroplast -10 and -35 sequences are not present. The deduced amino acid sequence of the thioredoxin gene from the red algae has the greatest similarity to type m thioredoxins, providing strong support for the hypothesis that type m thioredoxins in photosynthetic eukaryotes originated from an engulfed bacterial endosymbiont. Hybridization analysis of nuclear and chloroplast DNAs from several members of the phyla Chromophyta and Rhodophyta using P. yezoensis DNA as a probe demonstrated strong hybridization to the chloroplast and nuclear genomes of Griffithsia pacifica and a weak cross-hybridization to the chromophyte P. foliaceum. The G. pacifica chloroplast gene has a 66% identity with the P. yezoensis DNA, contains conserved active site amino acid residues, but lacks a methionine start codon.


Asunto(s)
Cloroplastos/química , Rhodophyta/genética , Tiorredoxinas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Núcleo Celular/química , Datos de Secuencia Molecular , Rhodophyta/ultraestructura , Homología de Secuencia de Aminoácido , Tiorredoxinas/química
9.
Cell ; 65(3): 507-15, 1991 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-2018976

RESUMEN

The mechanism that causes large regions of eukaryotic chromosomes to remain unreplicated until late in S phase is not understood. We have found that 67 kb of telomere-adjacent DNA at the right end of chromosome V in S. cerevisiae is replicated late in S phase. An ARS element in this region, ARS501, was shown by two-dimensional gel analysis to be an active origin of replication. Kinetic analyses indicate that the rate of replication fork movement within this late region is similar to that in early replicating regions. Therefore, the delayed replication of the region is a consequence of late origin activation. The results also support the idea that the pattern of interspersed early and late replication along the chromosomes of higher eukaryotes is a consequence of the temporal regulation of origin activation.


Asunto(s)
Replicación del ADN , ADN de Hongos/biosíntesis , Fase S , Saccharomyces cerevisiae/metabolismo , Secuencia de Bases , Cromosomas Fúngicos , Cinética , Saccharomyces cerevisiae/genética
10.
Mol Cell Biol ; 9(10): 4488-94, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2685553

RESUMEN

The replication of putative replication origins (ARS elements) was examined for 200 kilobases of chromosome III of Saccharomyces cerevisiae. By using synchronous cultures and transfers from dense to light isotope medium, the temporal pattern of mitotic DNA replication of eight fragments that contain ARSs was determined. ARS elements near the telomeres replicated late in S phase, while internal ARS elements replicated in the first half of S phase. The results suggest that some ARS elements in the chromosome may be inactive as replication origins. The actively expressed mating type locus, MAT, replicated early in S phase, while the silent cassettes, HML and HMR, replicated late. Unexpectedly, chromosome III sequences were found to replicate late in G1 at the arrest induced by the temperature-sensitive cdc7 allele.


Asunto(s)
Replicación del ADN/genética , Replicón/fisiología , Saccharomyces cerevisiae/genética , Mapeo Cromosómico , Cromosomas Fúngicos , Sondas de ADN , Cinética , Replicón/genética , Saccharomyces cerevisiae/metabolismo
11.
Meat Sci ; 24(2): 133-41, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-22055886

RESUMEN

Forty-eight fresh hams and bellies were obtained from 24 market weight hogs (x = 94·5 kg) of which twelve were electrically stimulated (ES) by pulsing current immediately after exsanguination. The left side of each non-stimulated (NS) carcas was fabricated after conditioning for 3h post mortem at 17°C (NS hot-processed). The left sides of ES carcasses were fabricated 1 h pm. The right sides were fabricated following a 24 h cooler chill at 2°C (conventionally chilled: CP). Hams from ESCP carcasses had higher (P < 0·05) smokehouse yields than hams from NS carcasses. Hams that were hot-processed had higher smokehouse yields than the NSCP hams. Time of fabrication (1, 3 or 24h post mortem) did not affect smokehouse yields. Conventionally chilled bellies obtained from ES carcasses showed higher (P < 0·05) residual nitrite levels than those front electrically stimulated hot-processed (ESHP) carcasses. No differences were found for residual nitrite levels in the non-electrically stimulated sides. Panelists were unable to detect any sensory differences from the bacon strips. Sensory scores of ham slices were more juicy for non-stimulated hot-processed carcasses (NSHP) than those from ESHP carcasses. Panelists found the ham slices from NSCP carcasses to be more tender (P < 0·05) than those from electrically stimulated cold-processed (ESCP) carcasses. Results from this study clearly indicated that hot-processing of pork can provide hams and bellies that are acceptable for the production of cured hams and bacon of comparable quality and yield to those currently being produced under conventional processing methods.

12.
Mol Cell Biol ; 7(10): 3566-73, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3316982

RESUMEN

We have examined the replication and segregation of the Saccharomyces cerevisiae 2 microns circle. The amplification of the plasmid at low copy numbers requires site-specific recombination between the 2 microns inverted repeat sequences catalyzed by the plasmid-encoded FLP gene. No other 2 microns gene products are required. The overexpression of FLP in a strain carrying endogenous 2 microns leads to uncontrolled plasmid replication, longer cell cycles, and cell death. Two different assays show that the level of Flp activity decreases with increasing 2 microns copy number. This regulation requires the products of the REP1 and REP2 genes. These gene products also act together to ensure that 2 microns molecules are randomly segregated between mother and daughter cells at cell division.


Asunto(s)
ADN de Hongos/genética , Proteínas Fúngicas/fisiología , Genes Fúngicos , Plásmidos , Saccharomyces cerevisiae/genética , Replicación del ADN , Regulación de la Expresión Génica , Genes , Mitosis , Proteínas Recombinantes de Fusión/genética , Recombinación Genética
13.
J Bacteriol ; 169(6): 2570-8, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3294798

RESUMEN

We have analyzed the functions encoded by the bgl operon in Escherichia coli K-12. Based on the ability of cloned regions of the operon to complement a series of Bgl- point mutations, we show that the three bgl structural genes, bglC, bglS, and bglB, are located downstream of the regulatory locus bglR in the order indicated. Using a bgl-lacZ transcriptional fusion, we show that bglC and bglS are involved in regulating operon expression. The presence of the bglC gene in trans is absolutely required for the expression of the fusion, which is constitutive when only the bglC gene is present. When the bglC and the bglS genes are both present in the cell, expression of the fusion requires a beta-glucoside inducer. From these observations, we conclude that (i) the bglC gene encodes a positive regulatory of bgl operon expression and (ii) the bglS gene encodes a negative regulator of operon expression, causing the requirement for a beta-glucoside inducer. These conclusions are supported by our observations that (i) a majority of bglC mutants exhibits a Bgl- phenotype, whereas rare trans-dominant mutations in bglC result in constitutive expression of the bgl operon and the fusion, and (ii) mutations in the bglS gene lead to constitutive expression of the fusion. Based on several lines of evidence presented, we propose that the bglS gene product has an additional role as a component of the beta-glucoside transport system.


Asunto(s)
Escherichia coli/genética , Genes Bacterianos , Glucósidos/metabolismo , Glicósidos/metabolismo , Operón , Arbutina/metabolismo , Alcoholes Bencílicos/metabolismo , Mapeo Cromosómico , Regulación de la Expresión Génica , Genes , Genes Reguladores , Mutación , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/genética , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/genética , Transcripción Genética
14.
J Mol Biol ; 191(1): 85-95, 1986 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-3025456

RESUMEN

The regulatory region (bglR) of the cryptic bgl operon was characterized by DNA sequence analysis and transcription mapping. Bgl(-)-specific transcription was found to occur in both the wild-type Bgl- and mutant Bgl+ cells. However, the steady-state level of bgl RNA was much higher in the Bgl+ mutant than in the wild-type. Activation of the bgl operon by insertion sequence-mediated bglR mutations or point mutations in bglR is therefore the result of increased transcription. The ethylmethane sulfonate-induced point mutations in bglR are alterations in a single base in the cAMP binding protein (CAP) binding site, leading to a stronger binding of the CAP-cAMP complex. The IS1 and IS5-mediated bglR mutations analyzed show that the insertion sequences can activate the bgl operon by integration 78 to 125 base-pairs upstream from the transcription initiation site. The role of the insertion sequences in activation of the bgl operon is discussed.


Asunto(s)
Proteínas Portadoras/genética , Proteína Receptora de AMP Cíclico , Elementos Transponibles de ADN , Elementos de Facilitación Genéticos , Regulación de la Expresión Génica , Genes Reguladores , Mutación , Secuencia de Bases , Proteínas Portadoras/metabolismo , AMP Cíclico/metabolismo , ADN Bacteriano , Escherichia coli/genética , Escherichia coli/metabolismo , Plásmidos , Transcripción Genética
17.
Cell ; 31(1): 43-51, 1982 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6297752

RESUMEN

Escherichia coli deletion mutants lacking DNA topoisomerase I have been identified previously and shown to grow at a normal rate. We show that such strains grow normally only because of spontaneously arising mutations that compensate for the topoisomerase I defect. Several of these compensatory mutations have been found to map at or near the genes encoding DNA gyrase, gyrA and gyrB. DNA gyrase assays of crude extracts show that strains carrying the mutations have lower gyrase activity. Thus the mutations are in the gyrase structural genes or in nearby regulatory sequences. These results, in conjunction with DNA supercoiling measurements of others, indicate that in vivo DNA superhelicity is a result of a balance between topoisomerase I and gyrase activities. An excess of negative supercoils due to an absence of topoisomerase I is deleterious to the cell, but a moderate gyrase deficiency is not harmful.


Asunto(s)
ADN-Topoisomerasas de Tipo II/genética , ADN-Topoisomerasas de Tipo I/genética , Escherichia coli/enzimología , Genes Bacterianos , Genes Virales , Mutación , Deleción Cromosómica , Escherichia coli/genética , Regulación de la Expresión Génica , Genotipo , Operón , Especificidad de la Especie , Transducción Genética
19.
Arch Ophthalmol ; 99(6): 1093-1100, 1981 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7236109

RESUMEN

We present an introduction to a clinical quantitative corneascope for measurement of corneal topography in detail. This instrument provides contour keratometry in all corneal meridians. We review the normal myopic and hyperopic eye contours, keratoconus, pellucid marginal degeneration, and wound gape and compression related to cataract surgery. We present a modified Placido disk for office use that incorporates the unique incident light image of the corneascope for rapid review of irregular corneal contours. Corneal topography irregularities frequently contribute to devastating refractive states of the eye and should be examined carefully when keratorefractive surgery is considered.


Asunto(s)
Córnea/anatomía & histología , Oftalmología/instrumentación , Enfermedades de la Córnea/patología , Humanos , Errores de Refracción/patología
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