Cese en el desarrollo radicular. Secuelas orales del Síndrome de Stevens-Johnson: Reporte de un caso / Cesse no desenvolvimento radicular. Sequelas orais da síndrome de Stevens-Johnson: relato de caso / Cease in root development. Oral sequelae of Stevens-Johnson Syndrome: A case report

Resumen El Síndrome de Stevens-Johnson (SSJ) y la Necrólisis Epidérmica Tóxica (NET) son enfermedades que se encuentran dentro del espectro de las reacciones adversas cutáneas severas. Estas enfermedades comprometen cavidad oral entre el 25% y 50% de los casos. Se presenta el caso de un paciente de 10 años de edad que sufrió unataque agudo de SSJ a la edad de 6 años. Con implicación de la cavidad oral debido a las secuelas que presenta mucosa oral, raíces cortas y poco desarrolladas en todos los órganos dentario sin otra causa atribuible en su historial médico, diferente al SSJ. La edad a la que se presentó la enfermedad y el estadio de desarrollo dental señalan como causa probable el ataque agudo de SSJ, lo que permite concluir que durante su curso ocurrió un daño en la vaina epitelial de Hertwig, provocando apoptosis y, en consecuencia, un cese en el desarrollo radicular.

Abstract Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are diseases that are within the spectrum of severe cutaneous adverse reactions. These diseases compromise the oral cavity in 25% to 50% of the cases. We present a case of a 10-year-old patient who suffered an acute attack of SJS at the age of 6 years. In the oral cavity, he presented sequelae in the oral mucosa, delayed root developed in all teeth, with no other cause attributable in its medical history, different to the SJS. The age at which the disease occurred and the stage of dental development point to that the acute SJS as a probable cause, which allows us to conclude that damage occurred in the Hertwig epithelial sheath during its course, causing apoptosis and, consequently, a cessation in root development.

Resumo A síndrome de Stevens-Johnson (SJS) e a Necrólise Epidérmica Tóxica (NET) são doenças que estão dentro do espectro de reações adversas cutâneas graves. Essas doenças comprometem a cavidade oral em 25% a 50% dos casos. É apresentado um caso de um paciente de 10 anos de idade que sofreu um ataque agudo de SJS aos 6 anos de idade. Na cavidade oral, apresentava sequelas na mucosa oral, raízes curtas e pouco desenvolvidas em todos os dentes, sem outra causa atribuível no seu histórico médico, diferente da SJS. A idade em que a doença ocorreu e o estágio do desenvolvimento dentário apontam o ataque agudo da SJS como causa provável, o que permite concluir que o dano ocorreu na bainha epitelial de Hertwig durante o seu curso, causando apoptose e, consequentemente, cesse no desenvolvimento radicular.

Long non-coding RNAs: Fine-tuning the developmental responses in plants

Plant developmental biology is associated with various gene regulatory pathways involved in different phases of their lifecycle. In course of development, growth and differentiation of different organs in plants are regulated by specific sets ofgene expression. With the advances in genomic and bioinformatic techniques, particularly high-throughput sequencingtechnology, many transcriptional units with no protein-coding potential have been discovered. Previously thought to be thedark matters of genome, long non-coding RNAs (lncRNAs) are gradually gaining importance as crucial players in generegulation during different developmental phases. Some lncRNAs, showing complementarity to microRNAs (miRNAs), areused as endogenous target mimics of specific miRNA family. A number of lncRNAs can also act as natural antisensetranscripts to attenuate the expression of coding genes. Although lncRNA-mediated regulations have extensively beenstudied in animals, plant lncRNA research is still in its initial phase. The present review highlights the regulatory mechanism and different physiological aspects of lncRNAs in plant development. In plants, lncRNAs are found to be associatedwith a number of plant developmental functions such as lateral root development, vernalization, photomorphogenesis,pollen development, fiber development and nodulation. Understanding these potent roles of lncRNAs in plant developmentcan further provide novel tools for crop improvement programs in future.

Root dysplasias of human teeth: a review / 中华口腔医学杂志

Tooth development is a complex physiological process, which goes through bud stage, cap stage, bell stage and root development stage. The aim of this review article is to report the clinical manifestations of root malformations and the mechanisms of root dysplasias of human teeth. The effects of epithelial root sheath on the development of tooth roots were also elaborated.

Root development in Bupleurum chinense and its impact factors / 中草药

Objective To identificate the development process and impact factors of lateral root in Bupleurum chinense. Methods The dynamic growth of lateral root primordia was observed by applying paraffin sectioning, and by light microscopy. In addition, the influence of growth regulators treatment on lateral root growth was also investigated. Results The lateral root primordium formation of B. chinense started near the pericycle cells, part of the endodermis cells also participated in this formation; 10 μmol/L IAA and Ca2+ greatly promoted the development of lateral root, but its high concentration inhibited lateral root emergence; 0.1 μmol/L TIBA and 10 μmol/L EDTA promoted the development of lateral root, but its high concentration inhibited lateral root emergence. Conclusion This research method can also be applied in other pharmaceutical plants, such as Angelica sinensis and Panax ginseng. So the study is very important to medicinal plant cultivation and breeding.

A clinical study on the revascularization of immature permanent teeth with infected necrotic pulp tissue and apical periodontitis / 实用口腔医学杂志

Objective:To evaluate the clinical effect of the revaseularization procedure for immature teeth with necrotic pulp and apical periodontitis.Methods:12 immature teeth with necrotic pulp and apical periodontitis in 12 patients(9-13 years old) were treated with revascularization protocol.The patients were followed up for 21-24 months.Results:All teeth were cured.4 types of responses were observed:①Increased thickening of the canal walls and continued root maturation;②Severe calcification of the canal space beneath MTA;③Partial pulp canal obliteration;④Continued root development with an open apex.Conclusion:Revascularization procedure may the formation of the root apex but not in all the cases.Excessive deposition of hard tissue might caused calcification in canal space.

Evaluation of the Impact of Alveolar Bone Resorption on the Root Formation of Molars in Transgenic Mice with RANK Over-expression / Evaluación del Imapacto de la Resorción Ósea Alveolar sobre la Formación Radicular de Molares en Ratones Transgénicos con Sobreexpresión de RANK

Alterations in the balance of the osteoblastic-osteoclastic activity (osteopetrosis, osteolysis) have an impact on the dental development. The over activation of the osteoclastogenesis pathway RANK/RANKL/OPG in RANKTg mice produces an acceleration of tooth eruption and root elongation, suggesting this pathway could control the speed of tooth formation. Evaluate the effect of osteoclastic hyperactivity on the root formation of molars in RANKTg mice. Histologic study both descriptive and comparative of the impact of hyper-resorption of the alveolar bone in Hertwig's epithelial root sheath (HERS) of molars in both RANKTg mice and controls. This is done through the immuno-detection of matrical, epithelial and cellular proliferation proteins with histological, histoenzymology and inmunohistochemical techniques. Osteoclastic hiperactivity in alveolar bone does not alter the root structure and integrity of molars in RANKTg mice; the acceleration in root formation does not alter the HERS integrity. An area of cellular hyper-proliferation in the apical follicular tissue of HERS was found, which could regulate root growth in response to osteoclastic activity. The overexpressed RANK produces an inhibition of amelogenin expression at 5 days of age, suggesting an indirect regulation of these cells by RANK/RANKL. Exploring other molecular factors expressed in HERS, and the related engram, would make possible the use of new therapies for the control of osseous and inflammatory pathologies during root formation.

Las alteraciones en el balance de la actividad osteoblástica-osteoclástica (osteopetrosis, osteolisis) tienen un impacto en el desarrollo dental. La activación de la vía sobre la osteoclastogénesis RANK/RANKL/OPG en ratones RANKTg produce una aceleración de la erupción de los dientes y elongación de las raíces, lo que sugiere que esta vía podría controlar la velocidad de formación de los dientes. El objetivo de este estudio consiste en evaluar el efecto de la hiperactividad osteoclástica en la formación de las raíces de los molares en ratones RANKTg. Se realizó un estudio histológico descriptivo y comparativo del impacto de la hiper-reabsorción del hueso alveolar sobre la vaina epitelial radicular (de Hertwig - HERS) de molares en ratones RANKTg y controles. Se realizó la inmuno-detección de la proliferación matricial, epitelial y celular de proteínas, combinada con técnicas histológicas, inmunohistoquímicas e histoenzimológicas. La hiperactividad osteoclástica en el hueso alveolar no altera la estructura de la raíz dentaria y la integridad de los molares en ratones RANKTg; la aceleración de la formación de la raíz no altera la integridad de la misma. Se encontró un área de hiper-proliferación celular en el tejido folicular apical del HERS, que podría regular el crecimiento de la raíz en respuesta a la actividad osteoclástica. La sobreexpresión en los RANK produce una inhibición de la expresión de amelogenina a los 5 días de edad, lo que sugiere una regulación indirecta de estas células por RANK/RANKL. La exploración de otros factores moleculares expresados en HERS, y el engrama relacionado, haría posible el uso de nuevas terapias para el control de patologías óseas e inflamatorias durante la formación de la raíz dentaria.

Autotransplantation of immature third molars; Pulp healing, periodontal healing and root development

PURPOSES: The aim of this study was to evaluate pulp healing, periodontal healing, root development of autotransplantation of immature third molars and show its viability in treatment of early loss of tooth in young patients MATERIALS AND METHODS: In this article we performed a retrospective study with 41 transplanted teeth in 36 patients. The Mean age at the time of surgery was 17 years(range 13-24 years) and mean postoperative follow up period was 2.4 years(range 1-6 years) We evaluated the survival rate, pulp healing, periodontal healing, root development of the above teeth RESULTS: At the last examination 40 teeth among 41 transplants were still present so survival rate was 97.6%. The pulpal healing was found in 38 teeth of 41 transplants. The periodontal healing was found in 38 transplants. The continuous root development was seen in 38 transplants. CONCLUSIONS: From the above results, the autotransplantation of immature third molars was found to be a useful and reliable treatment method for early loss of teeth in adolescents and young adults.

Sistema radicular de três porta-enxertos para lima ácida 'tahiti' no estado do Piauí / Evaluation of three rootstocks root system for acid lime 'tahiti' at Piauí state

O objetivo deste trabalho foi avaliar o desenvolvimento radicular de três porta-enxertos para lima ácida‘Tahiti’ [Citrus latifolia (Yu.Tanaka) Tanaka]: limão Cravo (C. limonia Osbeck); citrumelo Swingle[Poncirus trifoliata (L.) Raf. x C. paradisi Macf.]; trifoliata Flying Dragon (P. trifoliata (L.) Raf.var. (FD),no município de José de Freitas, Piauí, localizado a 04º 52’ latitude S e 42º 42’ longitude W, e altitude de110m, onde predomina clima Aw. Foram abertas trincheiras com quatro repetições, para colocação dequadro-gabarito de madeira, com divisórias de 0,1 m na profundidade por 0,2 m na largura, perfazendocinco camadas na profundidade e seis posições na largura, definindo quadrículas de 200 cm2 na parededas trincheiras, de onde foram obtidas fotografias digitais. Estas fotografias foram analisadas pelosoftware SIARCS 3.0 para dimensionamento do sistema radicular e os dados obtidos, submetidos àanálise de variância e posteriormente ao teste de Tukey, ao nível de 5% de probabilidade. O delineamentoexperimental foi inteiramente casualizado. Os sistemas radiculares dos porta-enxertos tiveramconcentração de 90% até a profundidade de 0,4 m, sendo que nos primeiros 0,2 m concentrou-se 60% docomprimento das raízes. O sistema radicular do limão Cravo demonstrou ser superior, em comprimento(cm.200 cm-2), aos dos porta-enxertos trifoliata Flying Dragon e citrumelo Swingle.

The objective of this work was to evaluate the development of the root system of three rootstocks for'Tahiti'acid lime [Citrus latifolia (Yu.Tanaka) Tanaka]: Rangpur lime (C. limonia Osbeck); Swinglecitrumelo [Poncirus trifoliata (L.) Raf. x C. paradisi Macf.]; Flying Dragon trifoliate (P. trifoliata (L.)Raf.var. (FD) ­ in the soil and environment conditions of the county of José de Freitas, Piauí, located on04º 52' latitude S and 42º 42' longitude W and 110 m of altitude, in Aw climate. It was used the trenchmethod. A wooden frame divided into 0.1 x 0.2 m parts was fixed in the soil profile and a digital photographwas taken from each part. These photographs were analyzed by software SIARCS 3.0 for sizing of theroot system and the data gotten, submitted to the analysis of variance with Tukey test at the level of 5%of probability. The experimental design was entirely randomized, with three treatments (rootstocks) andfour replications (trenches). The root systems of the rootstocks had 90% of concentration until thedepth of 0,4 m, and it was observed that 60% of the roots were concentrated in the first 0,2 m. The rootsystem of the Rangpur lime demonstrated to be superior, in lenght (cm.200 cm-²) to the Flying Dragontrifoliate and Swingle citrumelo root systems.