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1.
Rev. odontopediatr. latinoam ; 13: 224568, 2023. ilus
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1551941

RESUMO

Introducción: El objetivo principal de la terapia pulpar es mantener la integridad y salud de los dientes y sus estructuras de soporte. En odontopediatría, el tratamiento de molares primarios diagnosticados con pulpitis irreversible o necrosis pulpar representa uno de los grandes desafíos en la práctica clínica debido a la complejidad de la anatomía radicular, tiempo de trabajo y dificultad para la correcta instrumentación. La técnica "Lesion Sterilization Tissue Repair" (LSTR) busca esterilizar la lesión y reparar tejidos por medio del uso de pastas antibióticas sin la necesidad de instrumentar los canales radiculares. Reporte de caso: Paciente femenina de 9 años que asiste a la consulta odontológica asintomática. En el examen clínico el diente segundo molar primario lado mandibular izquierdo (diente #75) presenta lesión activa y cavitada de caries dental, absceso y movilidad grado I. En la radiografía periapical presenta área radiolúcida en la región de la furca, sugiriendo el diagnóstico de necrosis pulpar. Para el tratamiento pulpar se optó por realizar la técnica LSTR con la pasta CTZ, compuesta por cloranfenicol, tetraciclina, óxido de zinc y eugenol. Posteriormente, el molar fue restaurado con una corona de acero inoxidable. Después de 8 meses, el diente se encuentra asintomático, con la restauración satisfactoria, movilidad fisiológica e integridad gingival; radiográficamente hay ausencia de radiolucidez en la región de la furca y reabsorción ósea patológica. Conclusión: el tratamiento endodóntico en el molar primario con necrosis pulpar utilizando la técnica LSTR con la pasta CTZ presentó excelentes resultados clínicos y radiográficos


Introdução. O objetivo principal da terapia pulpar é manter a integridade e saúde dos dentes e de suas estruturas de suporte. Na odontopediatria, o tratamento de molares decíduos diagnosticados com pulpites irreversíveis ou necrose pulpar representa um grande desafio na prática clínica devido à complexidade da anatomia radicular, tempo de trabalho e dificuldade para uma correta instrumentação. A técnica "Lesión Sterilization Tissue Repair" (LSTR) busca esterilizar a lesão e reparar tecidos através de pastas antibióticas sem a necessidade da instrumentação dos canais radiculares. Relato de caso. Uma paciente do sexo feminino, 09 anos, assintomática e em acompanhamento na clínica odontológica, foi atendida com uma lesão ativa e cavitada de cárie no dente 75. O dente apresentava abscesso e mobilidade grau I. A radiografia periapical mostrou uma área radiolúcida na região de furca, sugerindo o diagnóstico de necrose pulpar. Para o tratamento pulpar, optou-se pela técnica LSTR com a pasta CTZ, composta por cloranfenicol, tetraciclina, óxido de zinco e eugenol. Posteriormente, o molar decíduo foi restaurado com coroa de aço. Após 8 meses, o dente encontra-se assintomático, com restauração satisfatória, mobilidade fisiológica e integridade gengival. Radiograficamente, há ausência de radiolucidez na região de furca e reabsorção óssea patológica. Conclusão. O tratamento endodôntico em molar decíduo com necrose pulpar utilizando a técnica LSTR com a pasta CTZ apresentou excelentes resultados clínicos e radiográficos


Introduction. The main goal of pulp therapy is to maintain the integrity and health of teeth and their supporting structures. In pediatric dentistry, the treatment of primary molars diagnosed with irreversible pulpitis or pulp necrosis is one of the great challenges in clinical practice due to the complexity of root anatomy, working time, and difficulty for correct instrumentation. The "Lesion Sterilization Tissue Repair" (LSTR) technique aims to sterilize the lesion and repair tissues through the use of antibiotic pastes without the need to instrument the root canals. Case report. A 9-year-old female patient attends the dental clinic asymptomatically. In the clinical examination, the second primary mandibular molar on the left side (tooth #75) presents an active and cavitated dental caries lesion, abscess, and grade I mobility. On the periapical radiograph, it presents a radiolucent area in the furcation region, suggesting the diagnosis of pulp necrosis. For pulp treatment, the LSTR technique with CTZ paste was chosen, composed of chloramphenicol, tetracycline, zinc oxide and eugenol. Subsequently, the molar was restored with a stainless steel crown. After 8 months, the tooth is asymptomatic, with satisfactory restoration, physiological mobility, and gingival integrity; radiographically there is no radiolucency in the furcation region and pathological bone resorption. Conclusion. The endodontic treatment in the primary molar with pulp necrosis using the LSTR technique with CTZ paste presented excellent clinical and radiographic results


Assuntos
Humanos , Feminino , Criança , Antibacterianos
2.
Mol Biol Evol ; 39(10)2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36149808

RESUMO

Appropriate flowering time is a crucial adaptation impacting fitness in natural plant populations. Although the genetic basis of flowering variation has been extensively studied, its mechanisms in nonmodel organisms and its adaptive value in the field are still poorly understood. Here, we report new insights into the genetic basis of flowering time and its effect on fitness in Panicum hallii, a native perennial grass. Genetic mapping in populations derived from inland and coastal ecotypes identified flowering time quantitative trait loci (QTL) and many exhibited extensive QTL-by-environment interactions. Patterns of segregation within recombinant hybrids provide strong support for directional selection driving ecotypic divergence in flowering time. A major QTL on chromosome 5 (q-FT5) was detected in all experiments. Fine-mapping and expression studies identified a gene with orthology to a rice FLOWERING LOCUS T-like 9 (PhFTL9) as the candidate underlying q-FT5. We used a reciprocal transplant experiment to test for local adaptation and the specific impact of q-FT5 on performance. We did not observe local adaptation in terms of fitness tradeoffs when contrasting ecotypes in home versus away habitats. However, we observed that the coastal allele of q-FT5 conferred a fitness advantage only in its local habitat but not at the inland site. Sequence analyses identified an excess of low-frequency polymorphisms at the PhFTL9 promoter in the inland lineage, suggesting a role for either selection or population expansion on promoter evolution. Together, our findings demonstrate the genetic basis of flowering variation in a perennial grass and provide evidence for conditional neutrality underlying flowering time divergence.


Assuntos
Poaceae , Locos de Características Quantitativas , Mapeamento Cromossômico , Ecótipo , Flores/genética , Interação Gene-Ambiente , Poaceae/genética
3.
Int J Paediatr Dent ; 32(2): 240-250, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34115431

RESUMO

BACKGROUND: Currently, there is no consensus on the superiority of any material for the restorative treatment of molars affected by molar-incisor hypomineralization (MIH). AIM: To evaluate the survival of restorations with stainless-steel crown (SSC) or composite resin (CR) in first permanent molars affected by MIH for 24 months. DESIGN: In this retrospective cohort study, 61 CR and 54 SSC restorations placed on molars affected by MIH of patients, aged between 7 and 10, that were treated and overseen at a university dental clinic in the period of 2017-2020 were evaluated. The primary outcome was the failure-free survival time. Parametric survival models were used for data censored by interval, and the comparison between SSC and CR was performed using the hazard ratio function with a 95% confidence interval. RESULTS: The survival of SSC and CR restorations after 24 months was 94.4% and 49.2%, respectively. This difference was influenced by the presence of previous restoration (aHR = 3.4; 95% CI: 1.2-9.4) and cusp involvement (aHR = 4.0; 95% CI: 1.5-11.2). CONCLUSION: In molars with MIH and the need for restorative treatment, SSC had a significantly higher survival rate than CR over 24 months.


Assuntos
Resinas Compostas , Hipoplasia do Esmalte Dentário , Criança , Coroas , Hipoplasia do Esmalte Dentário/terapia , Restauração Dentária Permanente , Humanos , Incisivo , Dente Molar , Estudos Retrospectivos , Aço
4.
Int J Paediatr Dent ; 32(1): 1-10, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33629389

RESUMO

BACKGROUND: The second permanent molar plays an important role when considering extraction of first permanent molars severely affected by molar-incisor hypomineralization (MIH). AIM: To assess the association between MIH and enamel hypomineralization of the second permanent molars in terms of presence and severity. DESIGN: In this retrospective cross-sectional study, permanent teeth were evaluated in 453 patients between the ages of 13 and 16 at a dental clinic, using intraoral photographs. A calibrated examiner classified enamel hypomineralization using the MIH index and dental caries experience using the DMFT and DMFS indices. Statistical analyses were performed using a linear generalized model and ordinal logistic regression. RESULTS: The most commonly affected teeth by enamel hypomineralization were permanent molars, whereas incisors, premolars, and canines were less affected. The presence of severe defects in the first permanent molars was associated with mild defects in the second permanent molars (OR = 4.01; 95% CI: 2.50-7.77). Enamel hypomineralization was associated with increased caries experience (PR = 5.54; 95% CI: 3.81-9.06). CONCLUSION: Enamel hypomineralization mainly affects the first and second permanent molars. Mild defects in the second permanent molars tend to be more frequent in patients with severe MIH in the first permanent molars. The presence of enamel hypomineralization was associated with higher dental caries experience.


Assuntos
Cárie Dentária , Incisivo , Adolescente , Estudos Transversais , Humanos , Dente Molar , Estudos Retrospectivos
5.
AoB Plants ; 13(2): plab002, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33708370

RESUMO

Geographic patterns of within-species genomic diversity are shaped by evolutionary processes, life history and historical and contemporary factors. New genomic approaches can be used to infer the influence of such factors on the current distribution of infraspecific lineages. In this study, we evaluated the genomic and morphological diversity as well as the genetic structure of the C4 grass Panicum hallii across its complex natural distribution in North America. We sampled extensively across the natural range of P. hallii in Mexico and the USA to generate double-digestion restriction-associated DNA (ddRAD) sequence data for 423 individuals from 118 localities. We used these individuals to study the divergence between the two varieties of P. hallii, P. hallii var. filipes and P. hallii var. hallii as well as the genetic diversity and structure within these groups. We also examined the possibility of admixture in the geographically sympatric zone shared by both varieties, and assessed distribution shifts related with past climatic fluctuations. There is strong genetic and morphological divergence between the varieties and consistent genetic structure defining seven genetic clusters that follow major ecoregions across the range. South Texas constitutes a hotspot of genetic diversity with the co-occurrence of all genetic clusters and admixture between the two varieties. It is likely a recolonization and convergence point of populations that previously diverged in isolation during fragmentation events following glaciation periods.

7.
Nat Commun ; 9(1): 5213, 2018 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-30523281

RESUMO

Environmental stress is a major driver of ecological community dynamics and agricultural productivity. This is especially true for soil water availability, because drought is the greatest abiotic inhibitor of worldwide crop yields. Here, we test the genetic basis of drought responses in the genetic model for C4 perennial grasses, Panicum hallii, through population genomics, field-scale gene-expression (eQTL) analysis, and comparison of two complete genomes. While gene expression networks are dominated by local cis-regulatory elements, we observe three genomic hotspots of unlinked trans-regulatory loci. These regulatory hubs are four times more drought responsive than the genome-wide average. Additionally, cis- and trans-regulatory networks are more likely to have opposing effects than expected under neutral evolution, supporting a strong influence of compensatory evolution and stabilizing selection. These results implicate trans-regulatory evolution as a driver of drought responses and demonstrate the potential for crop improvement in drought-prone regions through modification of gene regulatory networks.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Genômica/métodos , Panicum/genética , Estresse Fisiológico , Redes Reguladoras de Genes , Genes de Plantas/genética , Genótipo , Panicum/classificação , Filogenia , Locos de Características Quantitativas/genética , Especificidade da Espécie
8.
BMC Genomics ; 19(1): 792, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30384830

RESUMO

BACKGROUND: Understanding how and why genetic variation is partitioned across geographic space is of fundamental importance to understanding the nature of biological species. How geographical isolation and local adaptation contribute to the formation of ecotypically differentiated groups of plants is just beginning to be understood through population genomic studies. We used whole genome sequencing combined with association study of climate to discover the drivers of differentiation in the perennial C4 grass Panicum hallii. RESULTS: Sequencing of 89 natural accessions of P.hallii revealed complex population structure across the species range. Major population genomic separation was found between subspecies P.hallii var. hallii and var. filipes as well as between at least four major unrecognized subgroups within var. hallii. At least 139 genomic SNPs were significantly associated with temperature or precipitation across the range and these SNPs were enriched for non-synonymous substitutions. SNPs associated with temperature and aridity were more often found in or near genes than expected by chance and enriched for putative involvement in dormancy processes, seed maturation, response to hyperosmosis and salinity, abscisic acid metabolism, hormone metabolism, and drought recovery. CONCLUSIONS: Both geography and climate adaptation contribute significantly to patterns of genome-wide variation in P.hallii. Population subgroups within P.hallii may represent early stages in the formation of ecotypes. Climate associated loci identified here represent promising targets for future research in this and other perennial grasses.


Assuntos
Adaptação Biológica , Clima , Interação Gene-Ambiente , Genética Populacional , Genoma de Planta , Genômica , Panicum/fisiologia , Variação Genética , Genômica/métodos , Genótipo , Geografia
9.
Plant Physiol ; 172(2): 734-748, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27246097

RESUMO

Identifying the physiological and genetic basis of stress tolerance in plants has proven to be critical to understanding adaptation in both agricultural and natural systems. However, many discoveries were initially made in the controlled conditions of greenhouses or laboratories, not in the field. To test the comparability of drought responses across field and greenhouse environments, we undertook three independent experiments using the switchgrass reference genotype Alamo AP13. We analyzed physiological and gene expression variation across four locations, two sampling times, and three years. Relatively similar physiological responses and expression coefficients of variation across experiments masked highly dissimilar gene expression responses to drought. Critically, a drought experiment utilizing small pots in the greenhouse elicited nearly identical physiological changes as an experiment conducted in the field, but an order of magnitude more differentially expressed genes. However, we were able to define a suite of several hundred genes that were differentially expressed across all experiments. This list was strongly enriched in photosynthesis, water status, and reactive oxygen species responsive genes. The strong across-experiment correlations between physiological plasticity-but not differential gene expression-highlight the complex and diverse genetic mechanisms that can produce phenotypically similar responses to various soil water deficits.


Assuntos
Secas , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Genômica/métodos , Panicum/genética , Adaptação Fisiológica/genética , Ecossistema , Fotossíntese/genética , Folhas de Planta/genética , Análise de Componente Principal , Solo/química , Estresse Fisiológico , Água/metabolismo
10.
Acta biol. colomb ; 20(2): 163-173, mayo-ago. 2015. ilus, tab
Artigo em Inglês | LILACS | ID: lil-743853

RESUMO

Collections of frozen tissue samples stand as keystone sources of molecular information to construct biodiversity knowledge, and are particularly challenged if they focus on megadiverse countries. In 1998 the Humboldt Institute (Instituto de Investigación de Recursos Biológicos Alexander von Humboldt) began a tissue collection of Colombian biodiversity (IAvH-CT) and the aim of this work is to present a diagnostic and an historical perspective for that collection, constructed by compiling information and experiences on its management as well as by organizing and curating the information of each catalogued sample. After 16 years, the IAvH-CT harbors 16,469 samples, which represent around 2530 species from 1289 genera, and 323 families of the Colombian biodiversity. Samples are biased toward plants (44 %) and birds (40 %), but also include other animal taxa. Geographically, IAvH-CT includes samples from all Colombian departments, but there is broad variation in their coverage. When compared with other international collections, IAvH-CT fulfills several standards of sample storage and data management, but its major weakness is that several tissues seem to lack a vouchered specimen. Tissues housed at IAvH-CT have been included in at least 48 studies published in several scientific journals. IAvH-CT is implementing strategies to improve curatorial standards, fill-in taxonomic gaps, and to explore the potential of its samples to understand the outstanding Colombian biota in a cooperative research framework among institutions.


Las colecciones de tejidos son fuentes fundamentales de información molecular para el conocimiento de la biodiversidad, y son particularmente desafiantes si están enfocadas en países megadiversos. En 1998 el Instituto Humboldt (Instituto de Investigación de Recursos Biológicos Alexander von Humboldt) inició una colección de tejidos de la biodiversidad colombiana (IAvH-CT). El objetivo de este trabajo es presentar un diagnóstico y una perspectiva histórica de esta colección, mediante la compilación de información y de experiencias sobre su manejo y organizando y curando la información de cada muestra catalogada. Después de 16 años IAvH-CT resguarda 16,469 muestras, que representan alrededor de 2530 especies de 1289 géneros y 323 familias de la biodiversidad colombiana. El número de muestras está sesgado hacia plantas (44 %) y aves (40 %), pero también incluyen otros taxones animales. Geográficamente, IAvH-CT incluye muestras de todos los departamentos colombianos, pero hay una gran variación en su cobertura. Al ser comparada con otras colecciones internacionales se encuentra que IAvH-CT cumple varios estándares de almacenamiento de muestras y de manejo de datos, pero su gran debilidad es que varios tejidos aparentemente carecen de un ejemplar de referencia. Varios tejidos almacenados en IAvH-CT han sido incluidos en al menos 48 estudios publicados en varias revistas científicas. IAvH-CT está implementando estrategias para mejorar la curaduría, llenar vacíos taxonómicos y explorar el potencial de sus muestras para entender la impresionante biota colombiana en un marco de investigación en cooperación con otras instituciones.

11.
BMC Genomics ; 15: 527, 2014 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-24964784

RESUMO

BACKGROUND: In light of the changes in precipitation and soil water availability expected with climate change, understanding the mechanisms underlying plant responses to water deficit is essential. Toward that end we have conducted an integrative analysis of responses to drought stress in the perennial C4 grass and biofuel crop, Panicum virgatum (switchgrass). Responses to soil drying and re-watering were measured at transcriptional, physiological, and metabolomic levels. To assess the interaction of soil moisture with diel light: dark cycles, we profiled gene expression in drought and control treatments under pre-dawn and mid-day conditions. RESULTS: Soil drying resulted in reduced leaf water potential, gas exchange, and chlorophyll fluorescence along with differential expression of a large fraction of the transcriptome (37%). Many transcripts responded differently depending on time of day (e.g. up-regulation pre-dawn and down-regulation mid-day). Genes associated with C4 photosynthesis were down-regulated during drought, while C4 metabolic intermediates accumulated. Rapid changes in gene expression were observed during recovery from drought, along with increased water use efficiency and chlorophyll fluorescence. CONCLUSIONS: Our findings demonstrate that drought responsive gene expression depends strongly on time of day and that gene expression is extensively modified during the first few hours of drought recovery. Analysis of covariation in gene expression, metabolite abundance, and physiology among plants revealed non-linear relationships that suggest critical thresholds in drought stress responses. Future studies may benefit from evaluating these thresholds among diverse accessions of switchgrass and other C4 grasses.


Assuntos
Regulação da Expressão Gênica de Plantas , Metabolômica , Panicum/metabolismo , Transcriptoma , Secas , Panicum/genética , Fotossíntese/genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Análise de Sequência de RNA , Água/metabolismo
12.
J Pediatr Endocrinol Metab ; 27(9-10): 961-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24859509

RESUMO

Hypoparathyroidism, sensorineural deafness and renal dysplasia syndrome (HDRS) is comprised of a triad of conditions. It is an autosomal dominant condition caused by mutations in the GATA3 gene, located at 10p15, a critical region in the development of the embryonic parathyroid glands, inner ear, and kidneys. Here we describe the case of a patient with all three components of HDR syndrome diagnosed in the neonatal period who presented with cerebral infarction, hypocalcemia, and renal anomalies. Upon chromosomal microarray he was found to have an interstitial deletion at 10p, which produced a partial deletion in the GATA3 gene.


Assuntos
Infarto Cerebral/complicações , Fator de Transcrição GATA3/genética , Perda Auditiva Neurossensorial/diagnóstico , Hipocalcemia/complicações , Hipoparatireoidismo/diagnóstico , Rim/anormalidades , Nefrose/diagnóstico , Infarto Cerebral/genética , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Neurossensorial/genética , Humanos , Hipocalcemia/genética , Hipoparatireoidismo/complicações , Hipoparatireoidismo/genética , Lactente , Masculino , Mutação , Nefrose/complicações , Nefrose/genética
13.
Aesthet Surg J ; 31(1): 21-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21239669

RESUMO

BACKGROUND: Although rare, instances of visual loss after cosmetic blepharoplasty have been previously reported in the literature. OBJECTIVES: The goal of this study is to summarize the existing literature and report the results of a physician survey in order to provide appropriate guidelines for preventing, diagnosing, and treating this unfortunate complication. METHODS: A 13-question survey was sent to all members of the American Society for Aesthetic Plastic Surgery (ASAPS) and the British Association of Aesthetic Plastic Surgery (BAAPS). Surgeons were queried about their number of years in surgical practice, their average annual caseload of blepharoplasties, and the number of cases of visual loss. The survey also contained questions about the type of anesthesia administered, surgical technique, the presence of risk factors or comorbidities in patients, symptoms, time of presentation, management, and final outcome. RESULTS: A total of 648 responses were received from ASAPS members and 72 from BAAPS members. The overall number of blepharoplasties reported by these respondents was 752,816. Thirty-nine cases of visual loss were reported: 25 permanent and 14 temporary. According to this, the overall incidence of visual loss following blepharoplasty was calculated at 0.0052% (five of 100,000 cases, or one in 20,000). Permanent visual loss was calculated at 0.0033% (three in 100,000, or one in 30,000) and temporary visual loss at 0.0019% (two in 100,000, or one in 50,000). The most common symptoms in affected patients were pain and pressure. Development of symptoms was reported to occur within the first 24 hours, with two peaks: intraoperative to one postoperative hour, and six to 12 postoperative hours. Hypertension was the most common risk factor for postoperative visual loss. Retrobulbar hemorrhage was reported to be the main cause of blindness. The most common management technique reported was orbital decompression, followed by steroids and canthotomy. CONCLUSIONS: According to this study, blindness after blepharoplasty is a rare event. However, every step should be taken to prevent it. Prevention should begin in the preoperative period and should continue intraoperatively and postoperatively. Once the diagnosis of impending visual loss is made, it should be treated as a true surgical emergency, since early treatment has proven beneficial.


Assuntos
Blefaroplastia/efeitos adversos , Cegueira/etiologia , Complicações Pós-Operatórias/etiologia , Cegueira/epidemiologia , Cegueira/prevenção & controle , Coleta de Dados , Humanos , Hipertensão/complicações , Dor/epidemiologia , Dor/etiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Hemorragia Retrobulbar/complicações , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Reino Unido/epidemiologia , Estados Unidos/epidemiologia
14.
Plast Reconstr Surg ; 126(5): 231e-245e, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21042070

RESUMO

Reconstruction of the eyelids can range from simple repair to the integration of multiple complex procedures. Knowledge of eyelid anatomy, adequate preoperative planning, and meticulous surgical technique will optimize the anatomical and functional result. The purpose of this article is to review the relevant anatomy for eyelid reconstruction, to simplify defect analysis and preoperative planning, and to provide options for reconstruction of this complex area.


Assuntos
Blefaroplastia/métodos , Pálpebras/anatomia & histologia , Humanos
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