Association of mandibular canine impaction and anatomical factors: A multicentre retrospective panoramic study in Latin America.

INTRODUCTION: Mandibular canine impaction is infrequent in dental eruption anomalies and treatment is very challenging. The aim of this multicenter retrospective panoramic study in Latin America was to evaluate panoramic radiographic imaging characteristics of mandibular canine impaction (impaction area, mandibular base contact, transmigration, impaction height and sex) and their associations. MATERIAL AND METHODS: This cross-sectional study evaluated 212 digital panoramic radiographs from three radiological centres in Tingo Maria (Peru), Bogota and Tunja (Colombia). The study included children of both sexes with impacted mandibular canines. Mandibular alpha angle, contact with mandibular basal bone (MBB), impacted sector according to 10 sectors with an adaptation of the Ericson and Kurol method, presence of transmigration and the impacted height were measured and the relationship among these measures was analyzed. Fisher's exact test, Chi-square and binary logistic regression were used. (P<0.05). RESULTS: The mandibular canine impaction showed contact with the MBB (32.08%), dental transmigration (36.79%), mainly located at an apical (40.09%) and sub-apical (36.79%) level. Transmigration mainly occurred in sectors 6 (33.30%) and 10 (25.60%) (P<0.001). It was found that for each year of increase in age, the possibility of contact with the MBB decreased (ß=0.89, P=0.010), and as the alpha angle increased by one degree the probability of contact with the MBB decreased (ß=0.97, P=0.001) and the probability of transmigration increased (ß=1.05, P<0.001). CONCLUSIONS: One third of the impacted canines were in contact with the MBB, while another third presented dental transmigration and were mainly located apically and subapically of the incisor roots. These imaging features should be taken into account when planning orthodontic treatment.

Ectopic pregnancy with a contralateral corpus luteum: Case report.

The following report describes the case of an ectopic pregnancy with contralateral corpus luteum after spontaneous conception. The patient was a 33- year-old female (gravida 3, segmentary C sections 3), with positive pregnancy test, and an Intrauterine Device (IUD). The patient was asymptomatic. At vaginal ultrasound, we observed an anteverted uterus of normal shape and size, a 20 x 12 mm intramural myoma and an irregular endometrial thickness of 16.5 mm, with no intrauterine sac. An ectopic pregnancy in the left Fallopian tube and a contralateral corpus luteum were detected, possibly as consequence of ovum pick up through the opposite tube (oocyte transmigration). Further laparoscopic and histopathologic studies confirmed our findings, and the ectopic pregnancy was successfully removed. In conclusion, oocyte transmigration is a common event and should be account when we wish to provide medical advice to patients with a single Fallopian tube trying to conceive. There are real chances for a patient to become pregnant even when only a single tube is present.

Transmigration of Trypanosoma cruzi trypomastigotes through 3D cultures resembling a physiological environment.

To disseminate and colonise tissues in the mammalian host, Trypanosoma cruzi trypomastogotes should cross several biological barriers. How this process occurs or its impact in the outcome of the disease is largely speculative. We examined the in vitro transmigration of trypomastigotes through three-dimensional cultures (spheroids) to understand the tissular dissemination of different T. cruzi strains. Virulent strains were highly invasive: trypomastigotes deeply transmigrate up to 50 µm inside spheroids and were evenly distributed at the spheroid surface. Parasites inside spheroids were systematically observed in the space between cells suggesting a paracellular route of transmigration. On the contrary, poorly virulent strains presented a weak migratory capacity and remained in the external layers of spheroids with a patch-like distribution pattern. The invasiveness-understood as the ability to transmigrate deep into spheroids-was not a transferable feature between strains, neither by soluble or secreted factors nor by co-cultivation of trypomastigotes from invasive and non-invasive strains. Besides, we demonstrated that T. cruzi isolates from children that were born congenitally infected presented a highly migrant phenotype while an isolate from an infected mother (that never transmitted the infection to any of her children) presented significantly less migration. In brief, we demonstrated that in a 3D microenvironment each strain presents a characteristic migration pattern that can be associated to their in vivo behaviour. Altogether, data presented here repositionate spheroids as a valuable tool to study host-pathogen interactions.

The Trojan Horse Model in Paracoccidioides: A Fantastic Pathway to Survive Infecting Human Cells.

Paracoccidioidomycosis (PCM) is the most relevant systemic endemic mycosis limited to Latin American countries. The etiological agents are thermally dimorphic species of the genus Paracoccidioides. Infection occurs via respiratory tract by inhalation of propagules from the environmental (saprophytic) phase. In the lung alveoli the fungus converts to the characteristic yeast phase (parasitic) where interact with extracellular matrix proteins, epithelial cells, and the host cellular immunity. The response involves phagocytic cells recognition but intracellular Paracoccidioides have demonstrated the ability to survive and also multiply inside the neutrophils, macrophages, giant cells, and dendritic cells. Persistence of Paracoccidioides as facultative intracellular pathogen is important in terms of the fungal load but also regarding to the possibility to disseminate penetrating other tissues even protected by the phagocytes. This strategy to invade other organs via transmigration of infected phagocytes is called Trojan horse mechanism and it was also described for other fungi and considered a factor of pathogenicity. This mini review comprises a literature revision of the spectrum of tools and mechanisms displayed by Paracoccidioides to overcame phagocytosis, discusses the Trojan horse model and the immunological context in proven models or the possibility that Paracoccidioides apply this tool for dissemination to other tissues.

Transmigración de canino mandibular: etiología, manejo quirúrgico y consideraciones especiales / Mandibular canine transmigration: etiology, surgical management and special considerations

En raras ocasiones, el canino mandibular derecho o izquierdo se coloca en el lado opuesto al habitual. Esta perturbación se define como la transmigración. Existen diversas teorías de su etiología, así como factores que la condicionan. La transmigración mandibular es un término que no está descrito en la literatura contemporánea y son pocos los casos reportados a nivel mundial. Presentamos un caso de trasmigración de canino mandibular derecho, posicionado por debajo del agujero mentoniano de lado izquierdo, cerca del borde basal mandibular, el cual se extrajo bajo anestesia general. Presentamos la etiología, técnica quirúrgica y consideraciones especiales en casos de trasmigración de canino mandibular (AU)

In rare occasions right or left mandibular canine is positionated at opposed side of habitual. This disturbance is defined as transmigration. There exist diverse theories about its etiology as well as conditioning factors. Mandibular transmigration is a non described term in modern literature and there are only a few reported cases at world level. We present one case of right canine transmigration positionated intimately below of left side mentonian hole near of mandibular basal edge which it was extracted under general anesthesia. We present also the etiology, surgical technique and special considerations of mandibular canine transmigration cases (AU)

Transmigration of Trypanosoma cruzi Trypomastigotes through 3D Spheroids Mimicking Host Tissues.

While cellular invasion by T. cruzi trypomastigotes and intracellular amastigote replication are well-characterized events that have been described by using 2D monolayer cultures, other relevant parasite-host interactions, like the dynamics of tissue invasiveness, cannot be captured using monolayer cultures. Spheroids constitute a valuable three-dimensional (3D) culture system because they mimic the microarchitecture of tissues and provide an environment similar to the encountered in natural infections, which includes the presence of extracellular matrix as well as 3D cell-cell interactions. In this work, we describe a protocol for studying transmigration of T. cruzi trypomastigotes into 3D spheroids. In the experimental setup, cells and parasites are labelled with two fluorescent dyes, allowing their visualization by confocal microscopy. We also describe the general procedure and setting of the confocal microscope and downstream applications for acquisition and reconstruction of 3D images. This model was employed to analyze the transmigration of trypomastigotes from the highly virulent and pantropic RA T. cruzi strain. Of course, other aspects encountered by T. cruzi in the mammalian host environment can be studied with this methodology.

Cryptococcal dissemination to the central nervous system requires the vacuolar calcium transporter Pmc1.

Cryptococcus neoformans is a basidiomycetous yeast and the cause of cryptococcosis in immunocompromised individuals. The most severe form of the disease is meningoencephalitis, which is one of the leading causes of death in HIV/AIDS patients. In order to access the central nervous system, C. neoformans relies on the activity of certain virulence factors such as urease, which allows transmigration through the blood-brain barrier. In this study, we demonstrate that the calcium transporter Pmc1 enables C. neoformans to penetrate the central nervous system, because the pmc1 null mutant failed to infect and to survive within the brain parenchyma in a murine systemic infection model. To investigate potential alterations in transmigration pathways in these mutants, global expression profiling of the pmc1 mutant strain was undertaken, and genes associated with urease, the Ca2+ -calcineurin pathway, and capsule assembly were identified as being differentially expressed. Also, a decrease in urease activity was observed in the calcium transporter null mutants. Finally, we demonstrate that the transcription factor Crz1 regulates urease activity and that the Ca2+ -calcineurin signalling pathway positively controls the transcription of calcium transporter genes and factors related to transmigration.

Unusual transmigration of canines: report of two cases in a family

Introduction: Transmigration is pre-eruptive migration of tooth across the midline. The etiology of this rare anomaly is unknown. Transmigration is largely related to mandibular canines. Although maxillary canine transmigrations are found in the literature, they are still a rare entity. Objective: The aim of the present paper is to report two cases of unusual transmigrations of canines in two immediate members of a family and to report the first case of simultaneous transmigration of maxillary and mandibular canines in an Indian adolescent. Case report: A rare case of simultaneous transmigration of maxillary and mandibular canine in Indian adolescent along with bilateral transmigration of mandibular canines in her father is described here. Conclusion: Transmigration of canines in two immediate members of family needs to be further studied for familial occurrence of transmigration.

First case of bimaxillary transmigration of impactedcanines: report of a rare case and review of literature / Primeiro caso de transmigração bimaxilar de caninosimpactados: relato de um caso raro e revisão da literatura

Objective: To present a rare case of bimaxillary transmigration of impacted canines. Discussion: Preeruptivemigration of a tooth across the midline is termed transmigration. Transmigration typically affectsthe mandibular canines, but occurs rarely in maxillary canines as well. Transmigration of mandibular canineacross the midline is rare. An even less common finding is transmigration of maxillary canine acrossthe midline. The least common finding is bimaxillary occurrence of canines transmigration. Conclusion:Migration of both upper and lower canine teeth on the same side across the midline is called bimaxillarytransmigration, which is a very rare phenomenon of oral and maxillofacial complex, often undetected inroutine dental examination, neither clinical, nor periapical radiographic examination.

Objetivo: Apresentar um caso raro de transmigração bimaxilar de caninos impactados. Discussão: A migraçãopré-eruptiva de um dente através da linha média é denominado transmigração. A transmigraçãotipicamente afeta os caninos inferiores, mas pode ocorrer raramente em caninos superiores também. Transmigraçãode canino inferior através da linha média é rara, porém um achado ainda menos comum é a ocorrênciade transmigração bimaxilar de caninos. Conclusão: A migração de caninos superiores e inferiores nomesmo lado e cruzando a linha média é chamada de transmigração bimaxilar, um fenômeno raro de sistema bucal e maxilofacial, frequentemente diagnosticado em exame clínico odontológico de rotina ou exame radiográficoperiapical.

Bilateral transmigration of impacted mandibular canines: report of two cases and review / Transmigração bilateral de caninos inclusos mandibulares: relato de dois casos e revisão

Objective: To present and discuss a rare case of transmigration of bilateral mandibular canines. To review the literature and to discuss treatment. Discussion: Transmigration of the canine tooth is an uncommonphenomenon, often undetected in routine dental examinations. The less common finding is type 5 (the canine is positioned vertically in the midline with the long axis of the tooth crossing the midline)and the least common phenomenon is bilateral occurrence of type 5. There is no known etiology for its occurrence. Conclusion: Transmigration of mandibular canines across the midline is a rare condition. An even less common finding is bilateral transmigration of canines across the midline.

Objetivo: Apresentar e discutir um caso raro de transmigração bilateral de caninos mandibulares; revisar a literatura; e discutir tratamentos. Discussão: A transmigração de caninos é um fenômeno incomum que frequentemente não édetectado no exame clínico de rotina. O achado menos comum é o tipo 5 (canino posicionado verticalmente com o seulongo eixo cruzando a linha média) e o fenômeno menos comum é a ocorrência bilateral do tipo 5 de transmigração. A sua etiologia é desconhecida. Conclusão: A transmigração de caninos mandibulares cruzando a linha média é rara e um achado ainda menos comum é a transmigração bilateral de caninos cruzando a linha média.

Estudo da transmigração bacteriana na apendicite experimental em coelhos

The present study aims to evaluate the occurrence of the bacterial transmigration in induced ezxperimental appendicitis in rabbitis through complete oclusion of the vermiform appendix. 24 New Zealand white rabbits with a body weight ranging from 2500 to 3000 grams were used. They were divided into 2 groups. The animals from group I were submitted to a median laparotomy and fragments from the spleen, left kidney, right lung, abdominal limphonode, light content from the vermiform appendix and blood from the portal vein were withdrawn for culture. The animals from group 2 were submitted to median laparotomy and complete occlusion of the vermiform appendix in order to induce appendicitis and, after 24 hours, material was collected following the steps of group 1. It was not observed an increase in bacteria in the samples analysed in the Control Group Group 1). The increase of Escherichia coli was observed in all the animals from the Experiment Group (Group 2). The bacterial transmigration occured after 24-hour observation in rabbits with experimental appendicitis.

Introdução: A queda extrínseca dos mecanismos de defesa de um hospedeiro é vista classicamente como uma infecção, que resulta na aquisição de um tecido normal, de um novo microorganismo, cuja virulência é fundamental para a sua patogenia.Na década de 50, estudos comprovaram que bactérias e endotoxinas podem ultrapassar a barreira intestinal e atingir a circulação, demonstrando ainda, que a flora intestinal representa uma importante fonte para o desenvolvimento da infecção sistêmica. Objetivo: o presente estudo visa avaliar a ocorrência de transmigração bacteriana em apendicite experimental induzida em coelhos, mediante a oclusão completa do apêndice vermiforme. Métodos: foram utilizados 24 coelhos brancos, da linhagem Nova Zelândia, com peso corporal variando de 2500 a 3000 gramas, sendo então divididos em 2 grupos. Os animais do Grupo I foram submetidos a laparotomia mediana e retirada de fragmentos do baço, rim esquerdo, pulmão direito, linfonodo abdominal, conteúdo da luz do apêndice vermiforme e sangue da veia porta para cultura. Os animais do Grupo II foram submetidos a laparotomia mediana e oclusão completa do apêndice vermiforme para a indução de apendicite e, após 24 horas, realizada a coleta do material nos moldes do Grupo I. Resultados: No Grupo controle (Grupo I), não se observou o crescimento de bactérias nas amostras analisadas. No Grupo experimento (Grupo II), observou-se o crescimento de Escherichia coli em todos os animais. Conclusão: Ocorreu transmigração bacteriana após 24 horas de observação em coelhos com apendicite experimental.

Estudo da transmigração bacteriana na apendicite experimental em coelhos

The present study aims to evaluate the occurrence of the bacterial transmigration in induced ezxperimental appendicitis in rabbitis through complete oclusion of the vermiform appendix. 24 New Zealand white rabbits with a body weight ranging from 2500 to 3000 grams were used. They were divided into 2 groups. The animals from group I were submitted to a median laparotomy and fragments from the spleen, left kidney, right lung, abdominal limphonode, light content from the vermiform appendix and blood from the portal vein were withdrawn for culture. The animals from group 2 were submitted to median laparotomy and complete occlusion of the vermiform appendix in order to induce appendicitis and, after 24 hours, material was collected following the steps of group 1. It was not observed an increase in bacteria in the samples analysed in the Control Group Group 1). The increase of Escherichia coli was observed in all the animals from the Experiment Group (Group 2). The bacterial transmigration occured after 24-hour observation in rabbits with experimental appendicitis.

Introdução: A queda extrínseca dos mecanismos de defesa de um hospedeiro é vista classicamente como uma infecção, que resulta na aquisição de um tecido normal, de um novo microorganismo, cuja virulência é fundamental para a sua patogenia.Na década de 50, estudos comprovaram que bactérias e endotoxinas podem ultrapassar a barreira intestinal e atingir a circulação, demonstrando ainda, que a flora intestinal representa uma importante fonte para o desenvolvimento da infecção sistêmica. Objetivo: o presente estudo visa avaliar a ocorrência de transmigração bacteriana em apendicite experimental induzida em coelhos, mediante a oclusão completa do apêndice vermiforme. Métodos: foram utilizados 24 coelhos brancos, da linhagem Nova Zelândia, com peso corporal variando de 2500 a 3000 gramas, sendo então divididos em 2 grupos. Os animais do Grupo I foram submetidos a laparotomia mediana e retirada de fragmentos do baço, rim esquerdo, pulmão direito, linfonodo abdominal, conteúdo da luz do apêndice vermiforme e sangue da veia porta para cultura. Os animais do Grupo II foram submetidos a laparotomia mediana e oclusão completa do apêndice vermiforme para a indução de apendicite e, após 24 horas, realizada a coleta do material nos moldes do Grupo I. Resultados: No Grupo controle (Grupo I), não se observou o crescimento de bactérias nas amostras analisadas. No Grupo experimento (Grupo II), observou-se o crescimento de Escherichia coli em todos os animais. Conclusão: Ocorreu transmigração bacteriana após 24 horas de observação em coelhos com apendicite experimental.