Displasia fibrosa maxilar. Del diagnóstico al tratamiento. Reporte de caso / Maxillary fibrous dysplasia. From diagnosis to treatment: Case report / Displasia fibrosa maxilar. Do diagnóstico ao tratamento: Relato de caso

La displasia fibrosa se puede presentar, en cualquier persona, por una mutación en los primeros meses de gestación. Se trata de lesiones óseas benignas en pacientes jóvenes, en las que el tejido óseo normal es sustituido por tejido conectivo fibroso, debido a una alteración funcional de las células, siendo esta la antesala de una neoplasia. El objetivo de éste artículo es presentar un caso local de Displasia Fibrosa Maxilar, enfatizando el manejo clínico, radiográfico, pre y postoperatorio más pertinente. Por lo tanto, se describe el caso de un paciente adolescente de género masculino, afectado por displasia fibrosa en hemimaxilar derecho, a quien le fueron realizados los estudios imagenológicos e histopatológicos necesarios para obtener el diagnóstico definitivo y decidir el abordaje menos invasivo posible cumpliendo con estándares de estética facial; se realizó abordaje intrabucal para shaving óseo, con sedación consciente bajo estricta vigilancia de la especialista en anestesiología y reanimación. Una vez logrado el contorno deseado mediante el uso de piezas de mano de alta y baja velocidad, se realizó la sutura de los tejidos y el paciente egresó ambulante y con buen estado general de salud.

Fibrous dysplasia can occur in any person due to a mutation in the first months of gestation. These are benign bone lesions in young patients, in which the normal bone tissue is replaced by fibrous connective tissue, due to a functional alteration of the cells, being this the prelude to a neoplasm. The aim of this article is to present a local case of Maxillary Fibrous Dysplasia, emphasizing the most relevant clinical, radiographic, pre and postoperative management. Therefore, we describe the case of an adolescent male patient, affected by fibrous dysplasia in the right hemimaxillary, who underwent the necessary imaging and histopathological studies to obtain the definitive diagnosis and decide the least invasive approach possible in compliance with facial aesthetic standards; an intraoral approach was performed for bone shaving, with conscious sedation under strict supervision of the specialist in anesthesiology and resuscitation. Once the desired contour was achieved through the use of high and low speed handpieces, the tissues were sutured and the patient was discharged ambulatory and in good general health.

A displasia fibrosa pode ocorrer em qualquer pessoa devido a uma mutação nos primeiros meses de gestação. São lesões ósseas benignas em pacientes jovens, nas quais o tecido ósseo normal é substituído por tecido conjuntivo fibroso, devido a uma alteração funcional das células, sendo esse o prelúdio de uma neoplasia. O objetivo deste artigo é apresentar um caso local de Displasia Fibrosa Maxilar, enfatizando o manejo clínico, radiográfico, pré e pós-operatório mais pertinente. Portanto, descrevemos o caso de um paciente adolescente do sexo masculino, afetado por displasia fibrosa no hemimaxilar direito, que foi submetido aos exames de imagem e histopatológicos necessários para obter um diagnóstico definitivo e decidir sobre a abordagem menos invasiva possível, em conformidade com os padrões estéticos faciais; foi realizada uma abordagem intraoral para raspagem óssea, com sedação consciente sob estrita supervisão do especialista em anestesiologia e ressuscitação. Depois que o contorno desejado foi obtido com o uso de peças de mão de alta e baixa velocidade, os tecidos foram suturados e o paciente recebeu alta ambulatorial em bom estado geral de saúde.

Pliocene sigmodontine rodents (Mammalia: Cricetidae) in northernmost South America: test of biogeographic hypotheses and revised evolutionary scenarios.

We document the first occurrence of Sigmodontinae (Mammalia, Rodentia, Cricetidae) from the Pliocene of northern South America, from the San Gregorio Formation of northwestern Venezuela. The recovered isolated molars are identified as Oligoryzomys sp. and Zygodontomys sp., two currently widespread sigmodontines in South America. These records constitute the oldest representatives of these genera, potentially new species, and the first Pliocene occurrence for Oryzomyini and the whole subfamily outside Argentina. Hypotheses on the historical biogeography of sigmodontines have been constructed almost exclusively using genetic data and the fossils we report provide a new kind of evidence. The occurrence of Oligoryzomys sp. and Zygodontomys sp. in Venezuela provides novel information for the diversification models suggested for Oligoryzomys, by supporting a potential eastern corridor of open environments from northern to southern South America. The presence of sigmodontines from the locality home of the new reports, Norte Casa Chiguaje, is consistent with the palaeoenvironmental conditions originally proposed for it based on mammals and botanical records, being characterized as mixed open grassland/forest areas surrounding permanent freshwater systems. The new sigmodontine evidence is used to discuss the putative scenarios of the ancient evolution of the subfamily in South America, favouring a model in which open areas (savannahs) to the east of the Andes played crucial role aiding or obstructing Late Miocene-Pliocene sigmodontine dispersion southwards.

A new hybodontiform shark (Strophodus Agassiz 1838) from the Lower Cretaceous (Valanginian-Hauterivian) of Colombia.

The vertebrate marine faunas that inhabited northern South America during the Cretaceous are still poorly known. This study is a contribution to a growing wave of new studies on Lower Cretaceous vertebrates from Colombia. Here we report and describe a new species of a hybodontiform shark of the genus Strophodus, which we named Strophodus rebecae sp. nov., based on isolated teeth, that were collected in Valanginian-Hauterivian rocks of the Rosa Blanca Formation (Carrizal and El Sapo Members) near the town of Zapatoca, Santander Department, Andes of Colombia. In addition, we describe two other fragmented teeth assigned to Strophodus sp. from the Rosa Blanca Fm. The new species from Colombia represents the only Cretaceous record of Strophodus from Gondwana, offering new insights into the paleogeographic distribution of the genus, as well as increasing the knowledge about the scarce hybodontiform paleodiversity known from South America. The presence of Strophodus in the Rosa Blanca Formation suggests that these durophagous (shell-crushing) fishes played an important role as predators of the abundant and diverse invertebrate fauna present in these ancient tropical coastal ecosystems of Gondwana.

Sperm whales (Physeteroidea) from the Pisco Formation, Peru, and their trophic role as fat sources for late Miocene sharks.

Shark-cetacean trophic interactions, preserved as bite marks in the fossil record, mostly correspond to isolated or fragmentary findings that bear limited information about major trophic patterns or roles. Here, we provide evidence of focalized foraging by sharks in the form of tooth bite marks over physeteroids fossil bones from the late Miocene of Peru. These findings indicate that sharks were targeting the forehead of coeval physeteroids to actively feed on their lipid-rich nasal complexes. Miocene physeteroids displayed a broad diversity, including giant predatorial forms, small benthic foragers and suction feeders. Like their extant relatives, these animals exhibited enlarged fatty forehead organs responsible for their sound production capabilities, thus evolving taxon-specific cranial architecture. Bite marks are found on the cranial bones where these structures were attached, indicating that sharks actively targeted this region; but also, in areas that would only be accessible following the consumption of the surrounding soft tissues. The shape of the bite marks and their distribution suggests a series of consecutive scavenging events by individuals of different shark species. Similar bite patterns can be recognized on other Miocene physeteroids fossils from across the globe, suggesting that sharks actively exploited physeteroid carcasses as fat sources.

A Pliocene-Pleistocene continental biota from Venezuela.

The Pliocene-Pleistocene transition in the Neotropics is poorly understood despite the major climatic changes that occurred at the onset of the Quaternary. The San Gregorio Formation, the younger unit of the Urumaco Sequence, preserves a fauna that documents this critical transition. We report stingrays, freshwater bony fishes, amphibians, crocodiles, lizards, snakes, aquatic and terrestrial turtles, and mammals. A total of 49 taxa are reported from the Vergel Member (late Pliocene) and nine taxa from the Cocuiza Member (Early Pleistocene), with 28 and 18 taxa reported for the first time in the Urumaco sequence and Venezuela, respectively. Our findings include the first fossil record of the freshwater fishes Megaleporinus, Schizodon, Amblydoras, Scorpiodoras, and the pipesnake Anilius scytale, all from Pliocene strata. The late Pliocene and Early Pleistocene ages proposed here for the Vergel and Cocuiza members, respectively, are supported by their stratigraphic position, palynology, nannoplankton, and 86Sr/88Sr dating. Mammals from the Vergel Member are associated with the first major pulse of the Great American Biotic Interchange. In contrast to the dry conditions prevailing today, the San Gregorio Formation documents mixed open grassland/forest areas surrounding permanent freshwater systems, following the isolation of the northern South American basin from western Amazonia. These findings support the hypothesis that range contraction of many taxa to their current distribution in northern South America occurred rapidly during at least the last 1.5 million years.

Equatorial pliosaurid from Venezuela marks the youngest South American occurrence of the clade.

Pliosaurids were the dominant macropredators in aquatic environments at least since the Middle Jurassic until their extinction in the early Late Cretaceous. Until very recently, the Cretaceous record of Pliosauridae has been poor and difficult to interpret from the taxonomic and phylogenetic perspective. Despite that the knowledge of Cretaceous pliosaurids improved in recent years, numerous aspects of their evolutionary history still remain only poorly known. Here, we report the first pliosaurid material from Venezuela. The taxon is most likely earliest Cenomanian in age, thus representing the youngest occurrence of Pliosauridae from South America. The Venezuelan taxon is based on a well-preserved tooth crown whose morphology and outer enamel structural elements appear to resemble especially those observable in the giant pliosaurid Sachicasaurus vitae from the Lower Cretaceous of Colombia. The new discovery extends the pliosaurid record on the continent by more than 10 million years and likely marks the southernmost Upper Cretaceous occurrence of Pliosauridae, worldwide. We also briefly discuss the affinities of the enigmatic Venezuelan elasmosaurid Alzadasaurus tropicus and highlight similarities to elasmosaurids from the Western Interior Seaway.

A stem delphinidan from the Caribbean region of Venezuela.

The dense Miocene record of cetaceans is known from localities along the coasts of all continents, mostly in the northern Atlantic or the eastern Pacific regions, but Antarctica. Fossils from the Caribbean region are few and include of a couple of findings from Panama and Venezuela. Here, we report a partly complete skull from the Caujarao Formation (middle Miocene), Falcon State, Caribbean region of Venezuela. Our phylogenetic analyses indicate that the Caujarao specimen is a 'stem delphinidan', a group that includes several taxa of early diverging odontocetes whose phylogenetic affinities remain a matter of debate. The fossil record has shown that this group of stem delphinidans was taxonomically diverse, but displayed a somewhat homogeneous cranial patterning, with most of the variations being found within the mandible or tympanoperiotic characters. As other stem delphinidans the Caujarao odontocete displays an enlarged temporal fossa and a fairly symmetrical cranium. Because the skull is missing several key diagnostic characters due to the preservation state of the specimen, a more precise taxonomic identification is not possible. Despite this, the finding of this specimen highlights the importance of the fossil record from the Neogene of Venezuela, and the importance of the area to understand cetacean evolution in the proto-Caribbean.

Diversity and paleoenvironmental implications of an elasmobranch assemblage from the Oligocene-Miocene boundary of Ecuador.

The occurrence and diversity of elasmobranchs from the Oligocene-Miocene boundary from Tropical America is poorly known in comparison with the paleodiversity from younger Neogene intervals of the region. Here we describe a new elasmobranch assemblage from the rich fossil site of Montañita-Olón (Dos Bocas Formation, Santa Elena, Ecuador), where other vertebrates have already been described: for example, sea turtles and cetaceans. We report a total of 27 elasmobranch taxa, 19 of which are new fossil records for Ecuador, 10 new records for the Central Eastern Pacific and four new records for South America. Additionally, in order to reconstruct the environment where these marine remains were deposited, we performed abundance, paleobathymetric and habitat preference analyses, concluding that they were likely deposited in an outer neritic (open shelf) environment. The study of Oligocene and early Miocene marine elasmobranchs faunas in Tropical America is key to addressing the issues in the evolutionary history of this group.

Subtle Lisfranc Injuries: Fix It, Fuse It, or Bridge It?

The management of Lisfranc injuries is challenging considering the broad spectrum of energy involved and highly variable clinical presentation. Despite the advances in surgical techniques, subtle Lisfranc injuries can lead to chronic pain and permanent disability. Surgical treatment is mandatory for all the unstable injuries; however, the best surgical technique remains controversial. The most predictive factor for a successful outcome is the maintenance of anatomic alignment; therefore, the selection of the appropriate surgical technique is of paramount importance. This article reviews the current treatment options and describes the selection of the surgical technique based on the different clinical presentations.

Spondyloarthropathy in vertebrae of the aquatic Cretaceous snake Lunaophis aquaticus, and its first recognition in modern snakes.

Inflammatory arthritis is documented for the first time in snakes. Ossification of the intervertebral capsule and zygapophyseal joints resulting in segmental vertebral fusion was observed in the aquatic Cretaceous snake Lunaophis aquaticus. Such pathologic alterations are pathognomonic for the spondyloarthropathy form of inflammatory arthritis. A survey of 2144 snakes in recent collections, performed to identify Holocene prevalence, revealed only two occurrences in extant snakes. The findings in Bitis gabonica and Elaphe taeniura were indistinguishable from those noted in Lunaophis aquaticus and identical to those previously recognized in modern varanids. The pathology likely represents a form of reactive arthritis related to enteropathic infection. While the disease probably did not affect general locomotion, its vertebral column position may have compromised mating.

Neogene sharks and rays from the Brazilian 'Blue Amazon'.

The lower Miocene Pirabas Formation in the North of Brazil was deposited under influence of the proto-Amazon River and is characterized by large changes in the ecological niches from the early Miocene onwards. To evaluate these ecological changes, the elasmobranch fauna of the fully marine, carbonate-rich beds was investigated. A diverse fauna with 24 taxa of sharks and rays was identified with the dominant groups being carcharhiniforms and myliobatiforms. This faunal composition is similar to other early Miocene assemblages from the proto-Carribbean bioprovince. However, the Pirabas Formation has unique features compared to the other localities; being the only Neogene fossil fish assemblage described from the Atlantic coast of Tropical Americas. Phosphate oxygen isotope composition of elasmobranch teeth served as proxies for paleotemperatures and paleoecology. The data are compatible with a predominantly tropical marine setting with recognized inshore and offshore habitats with some probable depth preferences (e.g., Aetomylaeus groups). Paleohabitat of taxa particularly found in the Neogene of the Americas (†Carcharhinus ackermannii, †Aetomylaeus cubensis) are estimated to have been principally coastal and shallow waters. Larger variation among the few analyzed modern selachians reflects a larger range for the isotopic composition of recent seawater compared to the early Miocene. This probably links to an increased influence of the Amazon River in the coastal regions during the Holocene.

Neogene Proto-Caribbean porcupinefishes (Diodontidae).

Fossil Diodontidae in Tropical America consist mostly of isolated and fused beak-like jawbones, and tooth plate batteries. These durophagous fishes are powerful shell-crushing predators on shallow water invertebrate faunas from Neogene tropical carbonate bottom, rocky reefs and surrounding flats. We use an ontogenetic series of high-resolution micro CT of fossil and extant species to recognize external and internal morphologic characters of jaws and tooth plate batteries. We compare similar sizes of jaws and/or tooth-plates from both extant and extinct species. Here, we describe three new fossil species including †Chilomycterus exspectatus n. sp. and †Chilomycterus tyleri n. sp. from the late Miocene Gatun Formation in Panama, and †Diodon serratus n. sp. from the middle Miocene Socorro Formation in Venezuela. Fossil Diodontidae review included specimens from the Neogene Basins of the Proto-Caribbean (Brazil: Pirabas Formation; Colombia: Jimol Formation, Panama: Gatun and Tuira formations; Venezuela: Socorro and Cantaure formations). Diodon is present in both the Atlantic and Pacific oceans, whereas the distribution of Chilomycterus is highly asymmetrical with only one species in the Pacific. It seems that Diodon was as abundant in the Caribbean/Western Atlantic during the Miocene as it is there today. We analyze the paleogeographic distribution of the porcupinefishes group in Tropical America, after the complete exhumation of the Panamanian isthmus during the Pliocene.

Miocene flooding events of western Amazonia.

There is a considerable controversy about whether western Amazonia was ever covered by marine waters during the Miocene [23 to 5 Ma (million years ago)]. We investigated the possible occurrence of Miocene marine incursions in the Llanos and Amazonas/Solimões basins, using sedimentological and palynological data from two sediment cores taken in eastern Colombia and northwestern Brazil together with seismic information. We observed two distinct marine intervals in the Llanos Basin, an early Miocene that lasted ~0.9 My (million years) (18.1 to 17.2 Ma) and a middle Miocene that lasted ~3.7 My (16.1 to 12.4 Ma). These two marine intervals are also seen in Amazonas/Solimões Basin (northwestern Amazonia) but were much shorter in duration, ~0.2 My (18.0 to 17.8 Ma) and ~0.4 My (14.1 to 13.7 Ma), respectively. Our results indicate that shallow marine waters covered the region at least twice during the Miocene, but the events were short-lived, rather than a continuous full-marine occupancy of Amazonian landscape over millions of years.

Dysregulation and detection methods of EGFR in oral cancer: a narrative review / Desregulación y métodos de detección del EGFR en cáncer oral: revisión narrativa

Abstract: epidermal growth factor receptor (EGFR) is a transmembrane glycoprotein, with an intracellular domain and tyrosine kinase function (TK) involved in cell proliferation. Dysfunctions in EGFR signaling pathways have been associated with oral malignant tumors such as oral squamous cell carcinoma (OSCC). Dysfunctions of EGFR may result from: increased EGF ligand; EGFR overexpression and copy number gain of the EGFR gene (EGFR CNG); EGFR mutations; failure in the downregulation of EGFR; and EGFR crosstalk. Of these alterations, overexpression of EGFR is by far the most studied dysfunction in OSCC. Clinicians should identify possible alterations of EGFR in the oral mucosa of patients, as EGFR can act as a biomarker for the diagnosis and prognosis of OSCC. Currently, there are several methods and techniques for detecting EGFR. Immunohistochemistry (IHC), fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR), are used to identify overexpression of EGFR, EGFR CNG and EGFR mutations, respectively. Detection of EGFR as a biomarker is key to identify any oral malignant transformation. Consequently, it becomes imperative to implement a non-invasive and inexpensive method of early diagnosis for OSCC in clinical practice.

Resumen: el receptor del factor de crecimiento epidérmico (EGFR) es una glicoproteína transmembrana, con un dominio intracelular y función tirosina quinasa (TK) que participa en la proliferación celular. Las fallas en las vías de señalización del EGFR se han asociado con la formación de tumores malignos orales como el carcinoma oral de células escamosas (COCE). El incorrecto funcionamiento del EGFR puede producirse por: aumento del ligando EGF; sobreexpresion del EGFR y ganancia en el número de copias del gen EGFR (GNC EGFR); mutaciones del EGFR; falla en la regulación negativa del EGFR; y diafonía del EGFR. De las alteraciones mencionadas, la sobreexpresion de EGFR es por lejos la disfunción más estudiada en COCE. Para el clínico es importante poder identificar las posibles alteraciones del EGFR en la mucosa oral del paciente, esto debido a que el EGFR puede actuar como un biomarcador de diagnóstico y pronóstico para COCE. En la actualidad existen diversos métodos para detectar el EGFR. La inmunohistoquímica (IHC), la hibridación fluorescente in situ (FISH) y la reacción en cadena de la polimerasa (PCR), son técnicas utilizadas para identificar la sobreexpresion del EGFR, GNC EGFR y mutaciones del EGFR, respectivamente. La necesidad de detección de estas alteraciones se debe a la transcendencia del EGFR como biomarcador de transformación maligna. Lo anterior, hace necesario implementar un método de diagnóstico precoz para COCE que sea no invasivo y de bajo costo para la práctica clínica.

TGF-beta alterations in oral squamous cell carcinoma: narrative review / Alteraciones de TGF-beta en el carcinoma oral de células escamosas: revisión narrativa

The transforming growth factor beta (TGF-beta) is a cytokine that plays crucial roles in the regulation of angiogenesis, immune response, proliferation, migration and apoptosis of cells. In addition, it can inhibit cell progression and stimulate apoptosis in early stages of cancer. TGF-beta is a multifunctional homodimeric protein secreted by various cell lines, which have three different isoforms: TGF-beta1, TGF-beta2 and TGF-beta3. In normal conditions, TGF-beta1 activates some tumor suppressor cell signaling pathways that inhibit proliferation and are involved in cell migration, differentiation and apoptosis. However, in more advanced stages of cancer, when TGF-beta1 is altered, it acts as a promoter of tumorigenesis and may cause: 1) increased TGF-beta1, 2) overexpression of TGF-beta1 receptors (TbetaR), 3) TbetaR mutations, and 4) downregulation of TGF-beta receptor. In oral squamous cell carcinoma, the path is altered especially at the level of transmembrane receptors, with the TbetaR-II and TbetaR-III subtypes being the most affected. However, there is little information on the prognostic role it plays in the various types of cancers. It is important to study the signaling pathways of TGF-beta in order to develop techniques that may help detect their alterations and restore their normal operation. The objective of this review is to describe the alterations of TGF-beta in oral squamous cell carcinoma.

El factor de crecimiento transformante beta (TGF-beta) es una citocina que cumple funciones fundamentales en la regulación de la angiogénesis, respuesta inmune, proliferación, migración y apoptosis celular. Además, puede inhibir la progresión celular y estimular la apoptosis en etapas tempranas del cáncer. El TGF-beta es una proteína homodimérica multifuncional secretada por diversas líneas celulares, que presentan 3 isoformas: TGF-beta1, TGF-beta2 y TGF-beta3. En condiciones normales TGF-beta1 activa a algunas vías de señalización celular supresoras de tumores que inhiben la proliferación, y participan en la migración, diferenciación y apoptosis. Sin embargo, cuando esta se ve alterada, en etapas más avanzadas del cáncer actúa como promotor de la tumorogénesis, pudiendo producir: 1) aumento del TGF-beta1, 2) sobre expresión de los receptores del TGF-beta1 (TbetaR), 3) mutaciones de TbetaR, y 4) falla en la regulación negativa de TbetaR. En el carcinoma oral de células escamosas, la vía se ve alterada especialmente a nivel de sus receptores transmembranales, siendo los subtipos TbetaR-II y TbetaR-III los más afectados. Sin embargo, es escasa la información sobre el rol pronóstico que juega en los diversos tipos de cánceres. Es importante estudiar las vías de señalización de TGF-beta para desarrollar técnicas que detecten sus alteraciones y restauren el funcionamiento del sistema. El objetivo de esta revisión es describir las alteraciones de TGF-beta en carcinoma oral de células escamosas.

The Path towards Endangered Species: Prehistoric Fisheries in Southeastern Brazil.

Brazilian shellmounds are archaeological sites with a high concentration of marine faunal remains. There are more than 2000 sites along the coast of Brazil that range in age from 8,720 to 985 cal BP. Here, we studied the ichthyoarchaeological remains (i.e., cranial/postcranial bones, otoliths, and teeth, among others) at 13 shellmounds on the southern coast of the state of Rio de Janeiro, which are located in coastal landscapes, including a sandy plain with coastal lagoons, rocky islands, islets and rocky bays. We identified patterns of similarity between shellmounds based on fish diversity, the ages of the assemblages, littoral geomorphology and prehistoric fisheries. Our new radiocarbon dating, based on otolith samples, was used for fishery characterization over time. A taxonomical study of the ichthyoarchaeological remains includes a diversity of 97 marine species, representing 37% of all modern species (i.e., 265 spp.) that have been documented along the coast of Rio de Janeiro state. This high fish diversity recovered from the shellmounds is clear evidence of well-developed prehistoric fishery activity that targeted sharks, rays and finfishes in a productive area influenced by coastal marine upwelling. The presence of adult and neonate shark, especially oceanic species, is here interpreted as evidence of prehistoric fisheries capacity for exploitation and possibly overexploitation in nursery areas. Various tools and strategies were used to capture finfish in seasonal fisheries, over rocky reef bottoms and in sandy littoral environments. Massive catches of whitemouth croaker, main target dermersal species of South Atlantic coast, show evidence of a reduction in body size of approximately 28% compared with modern fisheries. Fishery activity involving vulnerable species, especially in nursery areas, could mark the beginning of fish depletion along the southeastern Brazilian coast and the collapse of natural fish populations.

An enigmatic aquatic snake from the Cenomanian of Northern South America.

We report the first record of a snake from the Cretaceous of northern South America. The remains come from the La Luna Formation (La Aguada Member, Cenomanian of Venezuela) and consist of several vertebrae, which belong to the precloacal region of the vertebral column. Comparisons to extant and extinct snakes show that the remains represent a new taxon, Lunaophis aquaticus gen. et sp nov. An aquatic mode of life is supported by the ventral position of the ribs, indicating a laterally compressed body. The systematic relationships of this new taxon are difficult to determine due to the scarcity of fossil material; it is, however, a representative of an early lineage of snakes that exploited tropical marine pelagic environments, as reflected by the depositional conditions of the La Aguada Member. Lunaophis is also the first aquatic snake from the Cenomanian found outside of the African and European Tethyan and Boreal Zones.

Osteosarcoma de fémur en un adulto y manejo con artroplastia no convencional. Reporte de un caso / Femur osteosarcoma in an adult and management with non-conventional arthroplasty. Report of a case

El osteosarcoma es el tumor óseo maligno primario más frecuente. Se caracteriza por la producción de osteoide tumoral (trabéculas óseas inmaduras) por parte de las células neoplásicas. Su mayor incidencia se da en la adolescencia y después de los 65 años. Son más comunes en varones y personas de raza negra. A pesar de su baja incidencia este tipo de lesión requiere una atención multidisciplinaria, diagnostico precoz, y tratamientos oportunos para aumentar la sobrevida y mantener la calidad de vida del paciente. En la actualidad y con los adelantos quirúrgicos-reconstructivos, la resección tumoral con cirugía de preservación del miembro es el tratamiento estándar para esta patología. Presentamos el caso de paciente masculino de 25 años quien presentó un osteosarcoma del fémur distal derecho. Fue tratado con quimioterapia adyuvante y resección en bloque y artroplastia total no convencional de la rodilla. Presentamos los resultados de su tratamiento y su evolución a largo plazo(AU)

Osteosarcoma is the most common primary malignant bone tumor. It's characterized by the production of tumor osteoid (immature bone trabeculae) by the neoplastic cells. His greatest incidence occurs in adolescence and after age 65. They are more common in males and blacks individuals. The low incidence of this type of injury, requires a multidisciplinary care, early diagnosis and appropriate treatments to increase survival and maintain quality of life of patients. Today, with the reconstructive surgical advances, tumor resection with limb-sparing surgery is the standard treatment for this condition. We present a 25 years old male patient who presented an osteosarcoma of the right distal femur. He was treated with adjuvant chemotherapy and en bloc resection and unconventional Total Knee Arthroplasty. We present the results of their treatment and long-term evolution(AU)

Influencia de la periodontitis en el carcinoma oral de células escamosas: revisión narrativa

El carcinoma oral de células escamosas (COCE) es el tipo de cáncer más frecuente en la cavidad oral, y constituye el 95% de la totalidad de neoplasias malignas a escala bucal. La etiología de COCE es multifactorial y su patogenia se ha asociado, entre otros, a los cambios que acontecen en su microambiente. La inflamación que invade el microambiente de COCE se ha relacionado con la invasión, progresión, carácter fuerte y pronóstico de COCE. Es por tal motivo, que la periodontitis, inflamación del tejido periodontal, de alta prevalencia en la población adulta, se ha relacionado con COCE. Al respecto, estudios clínicos advirtieron que la periodontitis representa un riesgo para desarrollar COCE y estudios in vitro, puntualizaron que la periodontitis favorece la tumorogenicidad y lo combativo de COCE. El objetivo de la siguiente revisión narrativa es describir los efectos de la periodontitis en el comportamiento del carcinoma oral de células escamosas.

Oral squamous cell carcinoma (OSCC) is the most common type of cancer in the mouth, accounting for 95% of all malignancies in the oral cavity. The etiology of OSCC is multifactorial and its pathogenesis has been associated, among others, with the changes that occur in its microenvironment. The inflammation that invades the OSCC microenvironment has been related to the invasion, progression, aggressiveness and prognosis of OSCC. It is for this reason that periodontitis, inflammation of the periodontal tissue, of high prevalence in the adult population, has been related to OSCC. In this regard, clinical studies reported that periodontitis presents a risk for developing OSCC and in vitro studies, reported that periodontitis favors the tumorogenicity and aggressiveness of OSCC. The aim of this review is to describe the effects of periodontitis on oral squamous cell carcinoma.

Sawfishes and Other Elasmobranch Assemblages from the Mio-Pliocene of the South Caribbean (Urumaco Sequence, Northwestern Venezuela).

The Urumaco stratigraphic sequence, western Venezuela, preserves a variety of paleoenvironments that include terrestrial, riverine, lacustrine and marine facies. A wide range of fossil vertebrates associated with these facies supports the hypothesis of an estuary in that geographic area connected with a hydrographic system that flowed from western Amazonia up to the Proto-Caribbean Sea during the Miocene. Here the elasmobranch assemblages of the middle Miocene to middle Pliocene section of the Urumaco sequence (Socorro, Urumaco and Codore formations) are described. Based on new findings, we document at least 21 taxa of the Lamniformes, Carcharhiniformes, Myliobatiformes and Rajiformes, and describe a new carcharhiniform species (†Carcharhinus caquetius sp. nov.). Moreover, the Urumaco Formation has a high number of well-preserved fossil Pristis rostra, for which we provide a detailed taxonomic revision, and referral in the context of the global Miocene record of Pristis as well as extant species. Using the habitat preference of the living representatives, we hypothesize that the fossil chondrichthyan assemblages from the Urumaco sequence are evidence for marine shallow waters and estuarine habitats.