Genome sequencing reveals molecular subgroups in oral epithelial dysplasia.

This study aimed to analyze the molecular characteristics of oral epithelial dysplasia (OED), highlighting the pathways and variants of genes that are frequently mutated in oral squamous cell carcinoma (OSCC) and other cancers. Ten archival OED cases were retrieved for retrospective clinicopathological analysis and exome sequencing. Comparative genomic analysis was performed between high-grade dysplasia (HGD) and low-grade dysplasia (LGD), focusing on 57 well-known cancer genes, of which 10 were previously described as the most mutated in OSCC. HGD cases had significantly more variants; however, a similar mutational landscape to OSCC was observed in both groups. CASP8+FAT1/HRAS, TP53, and miscellaneous molecular signatures were also present. FAT1 is the gene that is most affected by pathogenic variants. Hierarchical divisive clustering showed division between the two groups: "HGD-like cluster" with 4HGD and 2LGD and "LGD-like cluster" with 4 LGD. MLL4 pathogenic variants were exclusively in the "LGD-like cluster". TP53 was affected in one case of HGD; however, its pathway was usually altered. We describe new insights into the genetic basis of epithelial malignant transformation by genomic analysis, highlighting those associated with FAT1 and TP53. Some LGDs presented a similar mutational landscape to HGD after cluster analysis. Perhaps molecular alterations have not yet been reflected in histomorphology. The relative risk of malignant transformation in this molecular subgroup should be addressed in future studies.

Genome sequencing reveals molecular subgroups in oral epithelial dysplasia

Abstract This study aimed to analyze the molecular characteristics of oral epithelial dysplasia (OED), highlighting the pathways and variants of genes that are frequently mutated in oral squamous cell carcinoma (OSCC) and other cancers. Ten archival OED cases were retrieved for retrospective clinicopathological analysis and exome sequencing. Comparative genomic analysis was performed between high-grade dysplasia (HGD) and low-grade dysplasia (LGD), focusing on 57 well-known cancer genes, of which 10 were previously described as the most mutated in OSCC. HGD cases had significantly more variants; however, a similar mutational landscape to OSCC was observed in both groups. CASP8+FAT1/HRAS, TP53, and miscellaneous molecular signatures were also present. FAT1 is the gene that is most affected by pathogenic variants. Hierarchical divisive clustering showed division between the two groups: "HGD-like cluster" with 4HGD and 2LGD and "LGD-like cluster" with 4 LGD. MLL4 pathogenic variants were exclusively in the "LGD-like cluster". TP53 was affected in one case of HGD; however, its pathway was usually altered. We describe new insights into the genetic basis of epithelial malignant transformation by genomic analysis, highlighting those associated with FAT1 and TP53. Some LGDs presented a similar mutational landscape to HGD after cluster analysis. Perhaps molecular alterations have not yet been reflected in histomorphology. The relative risk of malignant transformation in this molecular subgroup should be addressed in future studies.

Long-term SARS-CoV-2 RNA shedding and its temporal association to IgG seropositivity.

Longitudinal characterization of SARS-CoV-2 PCR testing from COVID-19 patient's nasopharynx and its juxtaposition with blood-based IgG-seroconversion diagnostic assays is critical to understanding SARS-CoV-2 infection durations. Here, we retrospectively analyze 851 SARS-CoV-2-positive patients with at least two positive PCR tests and find that 99 of these patients remain SARS-CoV-2-positive after 4 weeks from their initial diagnosis date. For the 851-patient cohort, the mean lower bound of viral RNA shedding was 17.3 days (SD: 7.8), and the mean upper bound of viral RNA shedding from 668 patients transitioning to confirmed PCR-negative status was 22.7 days (SD: 11.8). Among 104 patients with an IgG test result, 90 patients were seropositive to date, with mean upper bound of time to seropositivity from initial diagnosis being 37.8 days (95% CI: 34.3-41.3). Our findings from juxtaposing IgG and PCR tests thus reveal that some SARS-CoV-2-positive patients are non-hospitalized and seropositive, yet actively shed viral RNA (14 of 90 patients). This study emphasizes the need for monitoring viral loads and neutralizing antibody titers in long-term non-hospitalized shedders as a means of characterizing the SARS-CoV-2 infection lifecycle.

Manejo Multidisciplinario de la Cavidad Oral en Pacientes COVID-19 bajo Ventilación Mecánica Invasiva. Rol del Equipo Odontológico / Multidisciplinary Management of the Oral Cavity in COVID-19 Patients under Invasive Mechanical Ventilation. Role of the Dental Team

RESUMEN: El objetivo de este artículo es presentar algunas consideraciones odontológicas y un protocolo de mantención para el manejo y cuidado de cavidad oral en pacientes en ventilación mecánica invasiva (VMI) en unidades de cuidados intensivos hospitalarios. Además, presentar recomendaciones para la implementación de estas. Desde el desarrollo del COVID-19 en el mundo, los casos de VMI prolongada han aumentado y junto con ellos, se ha visibilizado las complicaciones propias de este tipo de terapia, dentro de las cuales encontramos aquellas que afectan la cavidad oral. Los centros hospitalarios normalmente cuentan con servicios dentales conformados por distintas especialidades, las cuales en un trabajo mancomunado pueden entregar herramientas y educar al personal encargado para el cuidado de la cavidad oral en estos pacientes si es que son requeridos, siendo el odontólogo el encargado de evaluar las distintas situaciones clínicas y entregar directrices para la prevención y tratamiento de patología de la cavidad oral. En este trabajo se describen los pasos a seguir para realizar una correcta higiene oral de estos pacientes y el manejo de las distintas complicaciones posibles de observar, junto con la experiencia local de cómo solucionarlos de la mejor manera. Consideramos importante que las unidades de cuidados intensivos (UCI) conozcan el rol del odontólogo y las acciones que este equipo puede aportar en el cuidado de los pacientes hospitalizados para disminuir los riesgos asociados a ventilación prolongada, basados principalmente en el manejo de la higiene oral y lesiones asociadas.

ABSTRACT: The aim of this sutudy dental considerations and an oral cavity maintenance and care protocol in patients on invasive mechanical ventilation (IMV) in hospital intensive care units. Since the development of COVID-19 in the world, cases of prolonged IMV have increased and together with them, the complications of this type of therapy have been made visible, among which we find those that affect the oral cavity. Hospital centers normally have dental services made up of different specialties, which in a joint effort can provide tools and educate the personnel in charge of the care of the oral cavity in these patients if they are required, being the dentist the one in charge of evaluating and deliver guidelines for the prevention and treatment of pathology of the oral cavity. This work describes the steps to be followed to carry out correct oral hygiene in these patients and the management of the different complications that may be observed, along with local experience on how to best solve them. We consider important that the intensive care units (ICU) get to know the role of the dentist in the hospital environment and that they become part of the care of hospitalized patients to reduce the risks associated with prolonged ventilation, based mainly on oral hygiene management and associated injuries.

Long-term SARS-CoV-2 RNA Shedding and its Temporal Association to IgG Seropositivity.

Analysis of 851 COVID-19 patients with a SARS-CoV-2-positive PCR at follow-up shows 99 patients remained SARS-CoV-2-positive after four weeks from initial diagnosis. Surprisingly, a majority of these long-term viral RNA shedders were not hospitalized (61 of 99), with variable PCR Crossing point values over the month post diagnosis. For the 851-patient cohort, the mean lower bound of viral RNA shedding was 17.3 days (SD: 7.8), and the mean upper bound of viral RNA shedding from 668 patients transitioning to confirmed PCR-negative status was 22.7 days (SD: 11.8). Among 104 patients with an IgG test result, 90 patients were seropositive to date, with mean upper bound of time to seropositivity from initial diagnosis being 37.8 days (95%CI: 34.3-41.3). Juxtaposing IgG/PCR tests revealed that 14 of 90 patients are non-hospitalized and seropositive yet shed viral RNA. This study emphasizes the need for monitoring viral loads and neutralizing antibody titers in long-term shedders.

Quiste folicular inflamatorio en posición atípica: Revisión de la literatura a propósito de un caso / Follicular inflammatory cyst in atypical location: Case report and literature review

Objetivos: Mostrar la importancia de la histopatología en el diagnóstico del quiste folicular inflamatorio para un correcto tratamiento y la relevancia de una nomenclatura precisa. Material y Métodos: Búsqueda en Pubmed, ScienceDirect, EBSCO-host de «odontogenic-cysts¼, «dentigerous cyst of inflammatory origin¼ y "follicular inflammatory-cyst¼ como key-words, full-text en inglés o español de los últimos 10 años. Resultados: Paciente 10 años de edad, presenta tumoración vestibular de zona de diente 5.3, de consistencia dura, asintomático y cubierto por mucosa normal. Diente asociado sin lesiones cariosas. La radiografía evidenció una extensa área radiolúcida bien definida, rodeando la corona del diente 1.3, desplazando y reteniéndolo. Tras evaluación radiográfica, los diagnósticos diferenciales fueron tumor-odontogénico-adenomatoide, queratoquiste y QD. La histopatología confirmó QFI. Originándose la lesión a partir de la pieza 5.4 con tratamiento pulpar. Conclusiones: Se debe considerar al QFI como una lesión similar a otros quistes inflamatorios (paradentales o radiculares). Se sugiere considerar en dentición mixta, que QFI y quiste radicular del diente temporal son la misma lesión y las diferencias en su aspecto clínico dependerán del tiempo de evolución y la relación de proximidad entre folículo y proceso inflamatorio del diente temporal.

Objectives: To show the importance of histopathology in the diagnosis of follicular inflammatory cyst for a correct treatment and the relevance of a precise nomenclature. Material and Methods: Pubmed search, ScienceDirect, EBSCO-host "odontogenic cysts", "inflammatory dentigerous cyst" and "follicular inflammatory cyst" as keywords, full text in English or Spanish for the last 10 years. Results: A 10-year-old patient presented vestibular tumor of the tooth area 5.3, with a hard consistency, asymptomatic and covered by normal mucosa. Associated tooth without carious lesions. The radiograph evidenced a radiolucent area with well-defined limits, around the crown of the tooth 1.3, displacing and retaining it. After radiographic evaluation, the differential diagnoses were tumor-odontogenic-adenomatoid, keratocyst and QD. Histopathology confirmed QFI. Originating the lesion from piece 5.4 with pulp treatment. Conclusions: The QFI should be considered as an similar to other inflammatory (paradental or root) cysts. It is suggested to consider in mixed dentition, that QFI and radicular cyst of the temporal tooth are the same lesion and the differences in their clinical aspect will depend on the evolution time and the proximity relation between follicle and inflammatory process of temporal temporal.