Neurofibromatosis tipo 1 y manifestación en el Territorio Maxilofacial: Reporte de un caso y Revisión de la Literatura

Introducción: El neurofibroma corresponde a un tumor benigno que compromete la vaina neural del tejido nervioso, asociándose íntimamente a la neurofibromatosis. Debido al compromiso de nervios periféricos y/o centrales, su expresión clínica es muy variada producto de la compresión y/o desplazamiento de estructuras vecinas dificultando así su diagnóstico. Objetivo: El objetivo de este artículo, es el de realizar una revisión de la literatura en relación con la neurofibromatosis y sus manifestaciones en el territorio máxilofacial en conjunto con la presentación de un caso de hipercondilismo mandibular asociado a un neurofibroma en la región de la articulación temporomandibular en un paciente con antecedentes de neurofibromatosis. Métodos: Se presenta el caso de un paciente con laterognasia y antecedentes de Neurofibromatosis tipo I (NF1). Por medio de estudio imagenológico, se confirma Hipercondilismo derecho y presencia de una zona radiolúcida relacionada con el cuello del cóndilo comprometido, cuyo resultado histopatológico confirmo el diagnóstico de neurofibroma. Conclusiones: Existe una muy variada clínica en pacientes con NF1, presentando una predisposición a la formación de neurofibromas y alteraciones oseas que pudiesen comprometer el territorio máxilofacial y causar asimetrías faciales. Debido a esto, resulta imprescindible tener conocimiento y consideración de ambas patologías para una correcta planificación del tratamiento de los pacientes.

Introduction: Neurofibroma is a benign tumor that compromises the neural sheath of nerve tissue, intimately associated with Neurofibromatosis. Due to the involvement of peripheral and/or central nerves, its clinical expression is wide as a result of compression and/or displacement of neighboring structures, making its diagnosis difficult. Objective: The aim of this article is to review the literature on Neurofibromatosis and its manifestations in the maxillofacial territory, along with the presentation of a case of mandibular Hyperchondylism associated with a neurofibroma in the temporomandibular joint region in a patient with a history of Neurofibromatosis. Methods: We present the case of a patient with laterogenesis and a history of Neurofibromatosis type I (NF1). By imaging study, a right Hyperchondylism is detected along with the presence of a radiolucent area related to the neck of the compromised condyle, whose histopathological result confirmed the diagnosis of neurofibroma. Conclusions: There is a diverse clinical picture in patients with NF1, presenting a pre-disposition to neurofibromas development and bone abnormalities, leading to the compromise of the maxillofacial territory and causing facial asymmetries. Because of this, it is essential to have knowledge and consideration of both pathologies for the right planning of patient treatment.

The low affinity A2B adenosine receptor enhances migratory and invasive capacity in vitro and angiogenesis in vivo of glioblastoma stem-like cells.

Glioblastoma (GBM) is the most common and deadly malignant brain tumor, with a median survival of 15 to 17 months for a patient. GBM contains a cellular subpopulation known as GBM stem-like cells (GSCs) that persist in hypoxic niches and are capable of infiltrating into healthy brain tissue. For this reason, GSCs are considered one of the main culprits for GBM recurrence. A hypoxic microenvironment increases extracellular adenosine levels, activating the low affinity A2B adenosine receptor (A2BAR). Adenosine, through A2BAR, is capable of modulating invasiveness. However, its role in the invasion/migration of hypoxic-GSCs is still unknown. This study aims to understand the importance of A2BAR in modulating the migratory/invasive capacity of GSCs under hypoxia. Data analysis from The Cancer Genome Atlas (TCGA) program correlates A2BAR expression with high-grade glioma and hypoxic necrotic areas. U87MG and primary culture-derived GSCs under hypoxic conditions (0.5% O2) increased A2BAR mRNA and protein levels. As expected, the migratory and invasive capacity of GSCs increased under hypoxia, which was counteracted by blocking A2BAR, through the downregulation of MMP9 activity and epithelial-mesenchymal transition marker expression. Finally, in a xenograft mouse model, we demonstrate that treatment with MRS1754 did not affect the tumor volume but could decrease blood vessel formation and VEGF expression. Our results suggest that extracellular adenosine, through the activation of A2BAR, enhances the migratory and invasive capacity of GSCs in vitro under hypoxic conditions. Targeting A2BAR can be an effective therapy for GBM recurrence.

Ameloblastoma uniquístico patrón mural: Reporte de un caso

El ameloblastoma es un tumor odontogénico agresivo que se clasifica en uniquístico, extraóseo/periférico y metastatizante. Una mujer de 42 años acudió al Servicio de Cirugía Oral y Maxilofacial por aumento de volumen hemifacial izquierdo de 6 meses de evolución. Al examen se observó aumento de volumen de la región parotídea y submandibular izquierda, abombamiento tablas óseas mandibulares y movilidad dental. La tomografía axial computarizada reveló una lesión de aspecto quístico en la región mandibular. Se realizó la biopsia incisional y el tratamiento quirúrgico conservador. El diagnóstico histopatológico fue ameloblastoma uniquístico patrón mural. Luego de seis meses de descompresión, se realizó una nueva biopsia incisional, curetaje óseo y se aplicó solución de Carnoy. Once meses posteriores a la primera intervención, se constató radiográficamente aposición ósea de la lesión. El tratamiento de estos ameloblastomas continúa siendo controversial por lo que cada caso se debe abordar de manera única.

Ameloblastoma is an aggressive odontogenic tumor classified as unicystic, extraosseous / peripheral, and metastasizing. A 42-year-old woman was attended at the Oral and Maxillofacial Surgery Service due to a 6-month facial asymmetry. Clinically, we observed a volume increase of the left parotid and submandibular region, bulging of the mandibular bone tables and dental mobility. Computed Tomography revealed a cystic-like lesion in the mandibular region. An incisional biopsy and conservative surgical treatment were performed. The histopathological diagnosis was unicystic ameloblastoma, mural pattern. After six months of decompression, a new incisional biopsy and bone curettage were performed, and Carnoy's solution was applied. Eleven months after the first intervention, bone apposition was observed in the x-ray. The treatment of these ameloblastomas continues to be controversial, so every case should be approached in a unique manner.

Carcinoma ameloblástico mandibular: un diagnóstico infrecuente y desafiante / Mandibular ameloblastic carcinoma: an infrequent and challenging diagnosis

El carcinoma ameloblástico es un tumor odontogénico epitelial maligno, infrecuente y de mal pronóstico. Histopatológicamente es una lesión que conserva un patrón de diferenciación ameloblastomatoso, pero presenta características citológicas de malignidad. Debido a su rareza, existe poca información sobre su comportamiento biológico, el cual es reconocido en la literatura por ser inespecífico y variable, ya que puede presentarse como una lesión con características compatibles con una lesión benigna o como una entidad patológica agresiva altamente maligna. Esto último ha supuesto una dificultad no solo en su diagnóstico, sino también en la planificación terapéutica. Se reporta un caso de un carcinoma ameloblástico mandibular en un paciente perteneciente a la séptima década de la vida, destacando sus características clínicas, imagenológicas e histológicas variables que permitieron llegar a un diagnóstico correcto. (AU)

Ameloblastic carcinoma is a rare, malignant epithelial odontogenic tumor with a poor prognosis. Histopathologically it preserves an ameloblastomatous differentiation pattern but shows cytological features of malignancy. Due to its rarity, there is limited information on its biological behavior, which is recognized in the literature for being nonspecific and variable, as it may present as a lesion with characteristics compatible with a benign lesion or as a highly malignant aggressive pathological entity. The latter has been a difficulty not only in its diagnosis but also in the therapeutical planning. This article reports a case of a mandibular ameloblastic carcinoma occurring in a patient in the seventh decade of life, highlighting its variable clinical, imaging and histological characteristics that allowed us to reach a definitive diagnosis. (AU)

Mucormicosis Maxilar posterior, secundaria a una exodoncia: Reporte de un caso y revisión de la literatura / Posterior maxillary mucormycosis, secondary to an exodontics: A case report and literature review

RESUMEN: La Mucormicosis se describe como una infección fúngica de tipo oportunista y potencialmente mortal, reportándose en la literatura como la tercera en frecuencia, muy por detrás de la Candidiasis y Aspergilosis. Esta infección es causada por hongos de la familia de los Mucorales. Se presenta el caso de un hombre con Diabetes Mellitus II con un control metabólico deficiente, el cual posterior a una exodoncia, presenta una Mucormicosis Maxilar, presentando una etiología atípica y logrando ser confirmada posterior a biopsias y pruebas de cultivo, demostrando elementos del tipo Mucor. Se realizó una Maxilectomía parcial del lado afectado como tratamiento con una evolución favorable. Esta revisión destaca la importancia de la búsqueda activa basada en la semiología y la importancia de los exámenes complementarios, implicando lograr un correcto diagnóstico y pronóstico de la enfermedad.

ABSTRACT: Mucormycosis is described as an opportunistic and life-threatening fungal infection, being reported in the literature as the third in frequency, far behind candidiasis and aspergillosis. This infection is caused by fungi of the Mucorales family. We present the case of a man with Diabetes Mellitus II with poor metabolic control who, after an extraction, presents a Maxillary Mucormycosis, with an atypical etiology and confirmed after biopsies and culture tests, demonstrating elements of the Mucor type. A partial maxillectomy was performed on the affected side as a treatment with a favorable outcome. This review highlights the importance of active search based on semiology and of complementary examinations, implying a correct diagnosis and prognosis of the disease.

Decreased Equilibrative Nucleoside Transporter 1 (ENT1) Activity Contributes to the High Extracellular Adenosine Levels in Mesenchymal Glioblastoma Stem-Like Cells.

Glioblastoma multiforme is one of the most malignant types of cancer. This is mainly due to a cell subpopulation with an extremely aggressive potential, called glioblastoma stem-like cells (GSCs). These cells produce high levels of extracellular adenosine which has been associated with increased chemoresistance, migration, and invasion in glioblastoma. In this study, we attempted to elucidate the mechanisms that control extracellular adenosine levels in GSC subtypes. By using primary and U87MG-derived GSCs, we associated increased extracellular adenosine with the mesenchymal phenotype. [3H]-adenosine uptake occurred mainly through the equilibrative nucleoside transporters (ENTs) in GSCs, but mesenchymal GSCs have lower expression and ENT1-mediated uptake activity than proneural GSCs. By analyzing expression and enzymatic activity, we determined that ecto-5'-nucleotidase (CD73) is predominantly expressed in proneural GSCs, driving AMPase activity. While in mesenchymal GSCs, both CD73 and Prostatic Acid Phosphatase (PAP) contribute to the AMP (adenosine monophosphate) hydrolysis. We did not observe significant differences between the expression of proteins involved in the metabolization of adenosine among the GCSs subtypes. In conclusion, the lower expression and activity of the ENT1 transporter in mesenchymal GSCs contributes to the high level of extracellular adenosine that these GSCs present.

FK506 Attenuates the MRP1-Mediated Chemoresistant Phenotype in Glioblastoma Stem-Like Cells.

Poor response to current treatments for glioblastoma has been attributed to the presence of glioblastoma stem-like cells (GSCs). GSCs are able to expel antitumor drugs to the extracellular medium using the multidrug resistance-associated protein 1 (MRP1) transporter. Tacrolimus (FK506) has been identified as an MRP1 regulator in differentiated glioblastoma (GBM) cells (non-GSCs); however, the effect of FK506 on GSCs is currently unknown. The objective of the following research is to evaluate the effect of FK506 on the MRP1-related chemo-resistant phenotype of GSCs. For this, U87MG and C6 glioma cell lines were used to generate non-GSCs and GSCs. mRNA and MRP1-positive cells were evaluated by RT-qPCR and flow cytometry, respectively. A Carboxyfluorescein Diacetate (CFDA)-retention assay was performed to evaluate the MRP1 activity. Apoptosis and MTT assays were employed to evaluate the cytotoxic effects of FK506 plus Vincristine (MRP1 substrate). GSC-derived subcutaneous tumors were generated to evaluate the in vivo effect of FK506/Vincristine treatment. No differences in transcript levels and positive cells for MRP1 were observed in FK506-treated cells. Lesser cell viability, increased apoptosis, and CFDA-retention in the FK506/Vincristine-treated cells were observed. In vivo, the FK506/Vincristine treatment decreased the tumor size as well as ki67, Glial Fibrillary Acidic Protein (GFAP), and nestin expression. We conclude that FK506 confers a chemo-sensitive phenotype to MRP1-drug substrate in GSCs.

American lobster Cathepsin D, an aspartic peptidase resistant to proteolysis and active in organic solvents, non-ionic detergents and salts.

Suitable peptidases for biotechnological applications are those active at low temperature, in organic solvents, detergents or proteolytic additives. American lobster cathepsin D1 (CD1) is an enzyme highly efficient at 5-50°C and at pH 2.5-5.5. We assessed the effect of common industrial additives on CD1 activity. CD1 was isolated from lobster gastric fluid by chromatography. The proteolytic activity was measured using a fluorogenic specific substrate and the conformation by intrinsic fluorescence. Non-ionic detergents Tween-20 and Triton X-100 stabilize the peptidase activity. Ethanol, methanol and isopropanol [5-15% (v/v)] increased the enzyme activity up to 80%. The enzyme is active until 2.5M urea and is resistant to proteolysis by papain and renin. In this work, a crustacean peptidase that remains active when exposed to different chemical and proteolytic additives is reported, evincing that crustaceans are a good model for discovery of novel stable peptidases for future pharmaceutical, cosmetic and alimentary applications.

Agrandamiento gingival por ciclosporina: reporte de un caso / Gingival enlargement due to cyclosporine: a case report

El agrandamiento gingival (AG) es el aumento de volumen anormal de la encía que genera cambios estéticos y síntomas clínicos como sangrado gingival espontáneo o inducido, trastornos periodontales y migración patológica dentaria, entre otros. Este proceso patológico puede ser un efecto secundario a ciertos fármacos como anticonvulsivantes, bloqueadores de canales de calcio e inmunosupresores. Se presenta el caso de un paciente sexo masculino de 74 años de edad con antecedentes de trasplante renal, en tratamiento con ciclosporina, que acude por aumento del volumen intraoral, clínicamente compatible con agrandamiento gingival. Se realiza tratamiento basado en exodoncias, biopsia y control de placa. A los 2 meses se pudo observar una regresión de la lesión, y se confirma el diagnóstico con el estudio histopatológico. El manejo actual del tratamiento de esta enfermedad se basa en el control de la placa. Se sugiere dar un enfoque multidisciplinario y crear protocolos para derivar oportunamente antes de la expresión más agresiva de la enfermedad.

Gingival enlargement is an abnormal increased volume of the gum that induces cosmetic changes and clinical symptoms, such as gingival bleeding, periodontal disorders, pathological tooth migration, among others. This condition can be a side effect of certain drugs such as anticonvulsants, calcium channel blockers, and immunosuppressants. A 74 year-old male patient with a medical record of kidney transplant secondary to chronic renal failure receiving cyclosporine for the past 14 years is referred to our Hospital with the chief complaint of gingival enlargement. The treatment is based on tooth extractions, biopsy and periodontal treatment. A complete regression of the lesion was observed after two months. The current approach to treat this disease is focused on plaque control. A multidisciplinary approach should be used and clinical protocols prepared that allow early treatment and avoidance of more aggressive disease expression.

Oral metastasis of renal cell carcinoma, presentation of a case.

The oral cavity constitutes a site of low prevalence for metastasis of malignant tumors. Nevertheless, it has a high prevalence for metastasis of renal origin. Besides the kidneys, there are other primary sites with high prevalence of metastasis to the oral mucosa, such as the lungs, skin and breasts. Metastasis is common in patients with a background of treated renal tumors, thereby, it is proper to determine the possibility of oral metastasis as part of the protocol of attention. However, it constitutes a diagnostic challenge when it presents in patients with no renal antecedents. It is in this type of patients that the diagnosis of carcinoma is achieved by means of a metastasis. Survival rate in these patients is short because at the time of the metastasis diagnosis, the general compromise is high. The following report describes a case referred from the Rheumatology Unit with an intraoral tumor, that was finally diagnosed as a Metastasic Renal Cell Carcinoma with multiple metastasis.

Oral metastasis of renal cell carcinoma, presentation of a case

The oral cavity constitutes a site of low prevalence for metastasis of malignant tumors. Nevertheless, it has a highprevalence for metastasis of renal origin. Besides the kidneys, there are other primary sites with high prevalence ofmetastasis to the oral mucosa, such as the lungs, skin and breasts.Metastasis is common in patients with a background of treated renal tumors, thereby, it is proper to determine thepossibility of oral metastasis as part of the protocol of attention. However, it constitutes a diagnostic challengewhen it presents in patients with no renal antecedents. It is in this type of patients that the diagnosis of carcinomais achieved by means of a metastasis. Survival rate in these patients is short because at the time of the metastasisdiagnosis, the general compromise is high.The following report describes a case referred from the Rheumatology Unit with an intraoral tumor, that was finallydiagnosed as a Metastasic Renal Cell Carcinoma with multiple metastasis (AU)

Beckwith Wiedemann syndrome: presentation of a case report.

Beckwith Wiedemann Syndrome (BWS) is a rare congenital disease of low prevalence. However, it presents a high prevalence within the genetic pathologies of overgrowth. This syndrome presents typical manifestations such as macroglossia, macrosomy at birth, omphalocele and defects of the anterior abdominal wall. Its origin is known to be genetic, but its mechanism of generation is not clear. This syndrome has been the object of wide studies since investigators have established a relationship between the methods of assisted fertilization (assisted reproduction treatment, ART) and its appearance. Currently, research is oriented towards the improvement of the prenatal diagnostic techniques, which would allow a preparation of the multidisciplinary medical team to treat the pathologies with which these patients are born. Next we present the case of a 1 year-old child who consults this service with a diagnosis of macroglossia associated with BWS.

Beckwith Wiedemann Syndrome: Presentation of a case report

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Beckwith Wiedemann Syndrome (BWS) is a rare congenital disease of low prevalence. However, it presents a highprevalence within the genetic pathologies of overgrowth. This syndrome presents typical manifestations such asmacroglossia, macrosomy at birth, omphalocele and defects of the anterior abdominal wall. Its origin is known to be genetic, but its mechanism of generation is not clear. This syndrome has been the object of wide studies since investigators have established a relationship between the methods of assisted fertilization (assisted reproduction treatment, ART) and its appearance.Currently, research is oriented towards the improvement of the prenatal diagnostic techniques, which would allow a preparation of the multidisciplinary medical team to treat the pathologies with which these patients are born.Next we present the case of a 1 year-old child who consults this service with a diagnosis of macroglossia associated with BWS

Aspartic proteinases in the digestive tract of marine decapod crustaceans.

Decapod crustaceans synthesize highly active proteolytic enzymes in the midgut gland and release at least a part of them into the stomach where they facilitate the first step in peptide hydrolysis. The most common proteinases in the gastric fluid characterized so far are serine proteinases, that is, trypsin and chymotrypsin. These enzymes show highest activities at neutral or slightly alkaline conditions. The presence of acid proteinases, as they prevail in vertebrates, has been discussed contradictorily yet in invertebrates. In this study, we show that acid aspartic proteinases appear in the gastric fluid of several decapods. Lobsters Homarus gammarus showed the highest activity with a maximum at pH 3. These activities were almost entirely inhibited by pepstatin A, which indicates a high share of aspartic proteinases. In other species (Panulirus interruptus, Cancer pagurus, Callinectes arcuatus and Callinectes bellicosus), proteolytic activities were present at acid conditions but were distinctly lower than in H. gammarus. Zymograms at pH 3 showed in each of the studied species at least one, but mostly two-four bands of activity. The apparent molecular weight of the enzymes ranged from 17.8 to 38.6 kDa. Two distinct bands were identified which were inhibited by pepstatin A. Acid aspartic proteinases may play an important role in the process of extracellular digestion in decapod crustaceans. Activities were significantly higher in clawed lobster than in spiny lobster and three species of brachyurans. Therefore, it may be suggested that the expression of acid proteinases is favored in certain groups and reduced in others.

Isolation and characterization of trypsin from pyloric caeca of Monterey sardine Sardinops sagax caerulea.

Trypsin from pyloric caeca of Monterey sardine was purified by fractionation with ammonium sulfate, gel filtration, affinity and ionic exchange chromatography. Fraction 102, obtained from ionic exchange chromatography, generated one band in sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and isoelectric focusing. The molecular mass of the isolated trypsin was 25 kDa and showed esterase-specific activity on Nalpha-p-tosyl-L-arginine methyl ester (TAME) that was 4.5 times greater than amidase-specific activity on N-benzoyl-L-arginine-p-nitroanilide. The purified enzyme was partially inhibited by the serine-protease phenyl-methyl-sulfonyl fluoride (PMSF) inhibitor and fully inhibited by the soybean trypsin inhibitor (SBTI) and benzamidine, but was not inhibited by the metallo-protease inactivator EDTA or the chymotrypsin inhibitor tosyl-L-phenylalanine chloromethyl-ketone. The optimum pH for activity was 8.0 and maximum stability was observed between pH 7 and 8. A marked loss in stability was observed below pH 4 and above pH 11. Activity was optimum at 50 degrees C and lost activity at higher temperatures. The kinetic trypsin constants K(m) and k(cat) were 0.051 mM and 2.12 s(-1), respectively, while the catalytic efficiency (k(cat)/K(m)) was 41 s(-1) mM(-1). General characteristics of the Monterey sardine trypsin resemble those of trypsins from other fish, especially trypsins from the anchovy Engraulis japonica and Engraulis encrasicholus and the sardine Sardinops melanostica.