Extraosseous Calcifying Odontogenic Cyst Initially Interpreted as a Parulis.

Extraosseous variants of odontogenic cysts are an infrequent clinical finding, although they have a relatively indolent biological behavior compared to their intraosseous counterparts; due to their nature and clinical appearance, these lesions can be confused with multiple entities that affect soft tissues, so their diagnosis can only be achieved through surgical removal and subsequent histopathological analysis. The extraosseous/peripheral variant of calcifying odontogenic cyst (E/PCOC) has a heterogeneous clinical presentation mainly in terms of size and involvement or not of adjacent anatomical structures such as bone and teeth; in addition, there are few cases reported to date; thus, there are still clinical features to be elucidated. This report presents a child affected by E/PCOC in an unusual location, as well as its therapeutic management, which at first time was suspected of endodontic nature, due to a history of dental trauma.

Pleiotrophin and the Expression of Its Receptors during Development of the Human Cerebellar Cortex.

During embryonic and fetal development, the cerebellum undergoes several histological changes that require a specific microenvironment. Pleiotrophin (PTN) has been related to cerebral and cerebellar cortex ontogenesis in different species. PTN signaling includes PTPRZ1, ALK, and NRP-1 receptors, which are implicated in cell differentiation, migration, and proliferation. However, its involvement in human cerebellar development has not been described so far. Therefore, we investigated whether PTN and its receptors were expressed in the human cerebellar cortex during fetal and early neonatal development. The expression profile of PTN and its receptors was analyzed using an immunohistochemical method. PTN, PTPRZ1, and NRP-1 were expressed from week 17 to the postnatal stage, with variable expression among granule cell precursors, glial cells, and Purkinje cells. ALK was only expressed during week 31. These results suggest that, in the fetal and neonatal human cerebellum, PTN is involved in cell communication through granule cell precursors, Bergmann glia, and Purkinje cells via PTPRZ1, NRP-1, and ALK signaling. This communication could be involved in cell proliferation and cellular migration. Overall, the present study represents the first characterization of PTN, PTPRZ1, ALK, and NRP-1 expression in human tissues, suggesting their involvement in cerebellar cortex development.

Oral cancer and precancer in Oral Pathology and Medicine curricula of Mexican dental schools.

OBJECTIVE: To identify the teaching-learning process characteristics of Oral Pathology and Medicine (OP&M) related to oral potentially malignant disorders (OPMDs) and oral cancer (OC), in the dental schools' curricula in Mexico, to analyze the approach given to this topic worldwide, and to provide the possible solution strategies. MATERIALS AND METHODS: Questionnaires were sent to OP&M deans and professors from public Mexican Universities to explore the curriculum and academic profile of the dental schools. The recommendations gathered from a workshop with expert professors on the challenges in OPMD/OC teaching were reported. RESULTS: Twenty-two dental schools participated (22 deans, 30 professors). The most widely used strategies were clinical-case resolving (86%) and presentations (73%). Although 77.3% of the programs included maxillofacial lesions, only 40.9% contemplated OPMD/OC. Only 45% of the programs developed community activities for early OC detection. The workshop recommendations were (i) multidisciplinary approach to OPMD/OC teaching, involving OP&M professors in other dental and nondental courses; (ii) implementation of the most effective teaching techniques (currently, problem-based learning and clinical-case presentation) in OP&M curricula; (iii) education of OP&M professors on teaching-learning processes. CONCLUSIONS: These recommendations from the Mexican context, integrated with similar experiences from other countries could contribute to develop a unique, internationally acknowledged OP&M curriculum.

Vascular malformation of tongue with phlebothrombosis/phlebolith in a young patient: an unusual presentation.

Venous malformations (VMs) are a type of vascular malformation formed by abnormally developed venous channels, with variations in size, pathway and thickness and are therefore a condition which can predispose to thrombosis. We present the case of a VM associated with phlebothrombosis/phlebolith, located on the lingual dorsum of a 20-year-old female patient. Clinical examination revealed a nodule of approximately 5 mm in diameter involving the anterior third of lingual dorsum, with a firm, compressible and non-pulsatile consistency. Histopathologically, the lesion revealed a VM with evidence of phlebothrombosis and phlebolith development. Although VMs manifest infrequently in this age group, they should be considered in the differential diagnosis of other lesions with similar characteristics in young people.

Extraosseous odontogenic fibroma with a clear cells component: a 5-year follow-up.

The extraosseous/peripheral odontogenic fibroma (E/POF) is a benign mesenchymal odontogenic tumour found on the gingival surface with clinical characteristics identical to those of reactive lesions. A histopathological analysis is the only method for determining the difference between reactive lesions and these neoplastic lesions, whose recurrence potential varies between 38.9% and 50%, highlighting the importance of correct diagnosis. The following report describes an E/POF case with a clear cells component, as well as a long-term follow-up treatment, which we emphasise due to its potential for recurrence.

Host-Pathogen Molecular Factors Contribute to the Pathogenesis of Rhizopus spp. in Diabetes Mellitus.

Purpose of Review: Infectious diseases represent up to 12% of all deaths in people with diabetes mellitus (DM). The development and progression of DM generate a chronic inflammatory state with unique characteristics that have been exploited by some pathogens; one of them is Rhizopus spp., a fungus considered the causative agent of mucormycosis. This disease has a poor prognosis with high mortality rates, and the apparition of resistant isolates each year has become a worrying concern. DM is an actual and continuing health problem, and for that reason, it is of foremost importance to study the pathogenesis of mucormycosis to generate new prevention and treatment strategies. Recent Findings: The worldwide incidence of mucormycosis has increased in recent years. The pathogenic mechanisms and factors identified in Rhizopus spp. are the cell wall, spore germination, proteins, and enzymes related to iron sequestration, CotH fungal protein, positive regulation of the GRP78 cell receptor, and immune evasion due to survival within phagocytes, among others. The physiopathology of DM offers favorable conditions for the successful replication of Rhizopus spp. Summary: The main reason for increase of incidence of mucormycosis caused by Rhizopus spp. has been associated with the rise of worldwide prevalence of DM. Knowing the fungal pathogenic mechanisms as well as the relationships between Rhizopus with the microenvironment found in the human body will undoubtedly help generate better antifungals to enhance treatment outcomes. Nowadays, some strategies to combat the fungus are based on the knowledge of its proteins, cellular interactions, and iron metabolism.

Multiple calcifying hyperplastic dental follicles: a major diagnostic consideration in multiple pericoronal lesions - report of two cases.

BACKGROUND: Pericoronal radiolucent lesions are a common radiographic finding, but it is rare that they occur in multiple forms. Multiple calcifying hyperplastic dental follicles (MCHDF) are entities with few cases described to date; nevertheless, they appear to have a very particular phenotypic pattern. CASES PRESENTATION: Case 1: A 10-year-old male was evaluated radiographically, revealing four impacted canines, each accompanied by unilocular pericoronal radiolucency. Case 2: A 16-year-old male was planning orthodontic treatment; following his radiological evaluation all third molars were found to be accompanied with pericoronal radiolucencies. Enucleation, and third molar removal along with the pericoronal tissue were the respective treatments. Microscopically, in both cases, the specimens shown odontogenic epithelium, and type I and II calcifications in the hyperplastic follicles, all these characteristics were consistent with MCHDF. CONCLUSION: Although MCHDF are a rare entity, they must be considered in the differential diagnosis of multiple pericoronal lesions. Under the light of the current evidence, the histological findings may be relatively heterogeneous, but their integration with both the clinical data, which are apparently particular, and with the radiographic characteristics, can lead to a definitive diagnosis.

Molecular iodine exerts antineoplastic effects by diminishing proliferation and invasive potential and activating the immune response in mammary cancer xenografts.

BACKGROUND: The immune system is a crucial component in cancer progression or regression. Molecular iodine (I2) exerts significant antineoplastic effects, acting as a differentiation inductor and immune modulator, but its effects in antitumor immune response are not elucidated. METHODS: The present work analyzed the effect of I2 in human breast cancer cell lines with low (MCF-7) and high (MDA-MB231) metastatic potential under both in vitro (cell proliferation and invasion assay) and in vivo (xenografts of athymic nude mice) conditions. RESULTS: In vitro analysis showed that the 200 µM I2 supplement decreases the proliferation rate in both cell lines and diminishes the epithelial-mesenchymal transition (EMT) profile and the invasive capacity in MDA-MB231. In immunosuppressed mice, the I2 supplement impairs implantation (incidence), tumoral growth, and proliferation of both types of cells. Xenografts of the animals treated with I2 decrease the expression of invasion markers like CD44, vimentin, urokinase plasminogen activator and its receptor, and vascular endothelial growth factor; and increase peroxisome proliferator-activated receptor gamma. Moreover, in mice with xenografts, the I2 supplement increases the circulating level of leukocytes and the number of intratumoral infiltrating lymphocytes, some of them activated as CD8+, suggesting the activation of antitumor immune responses. CONCLUSIONS: I2 decreases the invasive potential of a triple negative basal cancer cell line, and under in vivo conditions the oral supplement of this halogen activates the antitumor immune response, preventing progression of xenografts from laminal and basal mammary cancer cells. These effects allow us to propose iodine supplementation as a possible adjuvant in breast cancer therapy.

Activation of peroxisome proliferator-activated receptor gamma is crucial for antitumoral effects of 6-iodolactone.

BACKGROUND: Molecular iodine (I2) exhibits antiproliferative and apoptotic effects on in vivo and in vitro cancer models. These effects are thought to be mediated by an iodinated arachidonic acid derivative, 6-iodolactone (6IL), and one of the proposed mechanisms is that 6IL activates Peroxisome Proliferator-Activated Receptors type gamma (PPARG). These receptors have been implicated in the inhibition of carcinogenic processes, in addition to their classical role in maintaining lipid and glucose homeostasis. The aim of this study was to determine whether PPARG participates in the 6IL antiproliferative and apoptotic effects on the mammary cancer cell line MCF-7. METHODS: The 6IL/PPARG complex was inhibited by the PPARG antagonist GW9662, in both an endogenous and overexpressed (adenoviral vector infection) context, and stable PPARG-knockdown MCF-7 cells (RNA interference, confirmed with hydrolysis probes and Western blot), were used to corroborate the PPARG participation. 6IL effects on proliferation (measured by Trypan Blue exclusion) and apoptosis (phosphatidylserine identification by flow cytometer) were evaluated in conditions of chemical inhibition (GW9662) and silencing (RNA interference). A wound-healing assay was conducted on wild-type and stable PPARG-knockdown MCF-7 cells to evaluate the antimigrational effect of 6IL. Caspase-8 activity was evaluated to determine if the extrinsic pathway is involved in the effects of 6IL and I2 treatment. RESULTS: Antiproliferative and pro-apoptotic 6IL effects require the activation of PPARG. In addition, wound-healing assays show that 6IL is able to inhibit MCF-7 cell migration and that PPARG plays a role in this phenomenon. Finally, the data exclude the participation of the extrinsic apoptotic pathway in 6IL- and I2-induced apoptosis. CONCLUSIONS: These results support the previously proposed mechanism, in which the I2 effects are mediated by 6IL, and they provide further support for the use of I2 as coadjuvant in breast cancer treatment.

6-iodolactone, key mediator of antitumoral properties of iodine.

An iodinated derivative of arachidonic acid, 5-hydroxy-6-iodo-8,11,14-eicosatrienoic acid, δ-lactone (6-IL) has been implicated as a possible intermediate in the autoregulation of the thyroid gland by iodine. In addition to antiproliferative and apoptotic effects observed in thyrocytes, this iodolipid could also exert similar actions in cells derived from extrathyroidal tissues like mammary gland, prostate, colon, or the nervous system. In mammary cancer (solid tumors or tumor cell lines), 6-IL has been detected after molecular iodine (I2) supplement, and is a potent activator of peroxisome proliferator-activated receptor type gamma (PPARγ). These observations led us to propose I2 supplement as a novel coadjutant therapy which, by inducing differentiation mechanisms, decreases tumor progression and prevents chemoresistance. Some kinds of tumoral cells, in contrast to normal cells, contain high concentrations of arachidonic acid, making the I2 supplement a potential "magic bullet" that enables local, specific production of 6-IL, which then exerts antineoplastic actions with minimal deleterious effects on normal tissues.

Leiomyomatous hamartoma: report of two cases and review of the literature.

Two cases of leiomyomatous hamartoma (LH) in patients of Latin ancestry are reported here. The first lesion was detected on the incisive papilla of a 19-year-old woman; this is an unusual age because these lesions are commonly observed during the first years of life. The second lesion found on the middle-dorsum of the tongue was observed in a 5-month-old boy. The diagnosis was based on the histopathological appearance and confirmed by immunohistochemistry with positivity for smooth muscle actin, muscle-specific actin, S-100 protein and desmin. To date, only 16 cases have been reported in the English-language literature. Controversial epidemiological data, histogenesis, clinical/histopathological features, and differential diagnosis are discussed herein.