Single-Cell RNA Transcriptome Helps Define the Limbal/Corneal Epithelial Stem/Early Transit Amplifying Cells and How Autophagy Affects This Population.

Purpose: Single-cell RNA-sequencing (scRNA-seq) was used to interrogate the relatively rare stem (SC) and early transit amplifying (TA) cell populations in limbal/corneal epithelia from wild-type and autophagy-compromised mice. Methods: We conducted scRNA-seq on ocular anterior segmental tissue from wild-type and beclin 1-deficient (beclin1+/-) mice, using a 10X Gemomics pipeline. Cell populations were distinguished by t-distributed stochastic neighbor embedding. Seurat analysis was conducted to compare gene expression profiles between these two groups of mice. Differential protein expression patterns were validated by immunofluorescence staining and immunoblotting. Results: Unbiased clustering detected 10 distinct populations: three clusters of mesenchymal and seven clusters of epithelial cells, based on their unique molecular signatures. A discrete group of mesenchymal cells expressed genes associated with corneal stromal SCs. We identified three limbal/corneal epithelial cell subpopulations designated as stem/early TA, mature TA, and differentiated corneal epithelial cells. Thioredoxin-interacting protein and PDZ-binding kinase (PBK) were identified as novel regulators of stem/early TA cell quiescence. PBK arrested corneal epithelial cells in G2/M phase of the cell cycle. Beclin1+/- mice displayed a decrease in proliferation-associated (Ki67, Lrig1) and stress-response (H2ax) genes. The most increased gene in beclin1+/- mice was transcription factor ATF3, which negatively regulates limbal epithelial cell proliferation. Conclusions: Establishment of a comprehensive atlas of genes expressed by stromal and epithelial cells from limbus and cornea forms the foundation for unraveling regulatory networks among these distinct tissues. Similarly, scRNA-seq profiling of the anterior segmental epithelia from wild-type and autophagy-deficient mice provides new insights into how autophagy influences proliferation in these tissues.

Exiting the limbo of perimortem trauma: A brief review of microscopic markers of hemorrhaging and early healing signs in bone.

The assessment and interpretation of the timing of skeletal trauma can be of extreme difficulty in post-mortem specimens, especially because of post-mortem processes and taphonomic events. The chronological diagnosis of bone trauma, consisting usually in the gross distinction between antemortem, perimortem and post-mortem, is based almost uniquely on macroscopic and morphologic parameters in the anthropological field. However, both the interference of taphonomy and the scarce persistence of specific features indicating vitality (meaning etymologically "produced in life") and/or some very early bone healing reactions, make it extremely difficult. In this perspective, it is important not only to distinguish between peri and post-mortem lesions, but also to interpret perimortem lesions with respect to vitality and time elapsed since the trauma which may change the course of the investigations. And techniques of forensic pathology applied to forensic anthropology can come in extremely handy. If any traces of vital blood extravasation, haemorrhage, hematoma, inflammation, and biomarkers of early healing reaction are found in the bone tissue of a skeletal lesion (regardless the state of preservation of the body), then can they be used as a diagnostic tool or marker of vitality for that lesion? In these terms, vital reactions like bleeding or any early sign of bone healing can be the only evidence for demonstrating that a traumatic event was prior the death. Nevertheless, very little information, or research for that matter, is available in literature concerning persistence and detectability of vitality markers during the bone decomposition process. A fundamental point for properly determining the vitality of a fracture and estimating the post-traumatic time interval in skeletal lesions is the physio-pathological picture of the very initial healing process. This article attempts to provide a review of the physiopathological current knowledge available and applicable to osteology.

Intervención de los fibrocitos del ligamento espiral en la regulación metabólica del oído interno / Intervention of spiral ligament fibrocytes in the metabolic regulation of the inner ear

El mantenimiento de un gradiente de K+ entre la endolinfa y la perilinfa es imprescindible para la audición normal y depende inicialmente de la actividad de la estría vascular. La presencia de abundante Na-K-ATPasa en las células marginales de la estría vascular proporciona un mecanismo de bombeo al objeto de preservar la cantidad de K+ en la endolinfa y, consecuentemente, el potencial endococlear. Los fibrocitos de la pared lateral coclear suministran K+ a la estría, vía gap junctions, mediante la recirculación hacia la estría de los iones que fluyen desde la escala media durante la transducción auditiva. La pared lateral de la cóclea contiene cinco tipos de fibrocitos, que se diferencian según su localización, sus características estructurales y su contenido de enzimas que median o facilitan la energía para el transporte iónico. La rotura de las uniones como los puentes celulares por mutaciones de conexinas y otras condiciones patológicas conduce al bloqueo de las vías de recirculación de K+. La expresión de coclina y otorraplina, proteínas que intervienen en funciones estructurales o reguladoras del oído interno, indica una diversidad y una complejidad de los tejidos mesenquimales mayores que lo imaginado previamente. La presencia de otospiralina, una proteína novedosa encontrada en los fibrocitos del limbo espiral, el ligamento espiral y las regiones subepiteliales del vestíbulo, es un hallazgo muy importante, ya que dicha proteína se ha mostrado esencial para la supervivencia de las células ciliadas y las células de sostén del oído interno. Conocer y entender mejor la función de los fibrocitos proporcionará un nuevo y prometedor abordaje etiopatogénico para el tratamiento de las enfermedades del oído interno (AU)

Maintenance of the K+ gradient between endolymph and perilymph is essential for normal hearing and depends primarily on the activity of the stria vascularis. Abundant Na-K-ATPase in marginal strial cells provides a pumping mechanism for preserving the K+ level of the endolymph and consequently, the endocochlear potential. Fibrocytes in the lateral wall of the cochlea supply K+ to the strial pump, via gap junctions, by recycling back into the stria the ions that efflux from the scala media during auditory transduction. The lateral wall of the cochlea encloses five types of fibrocytes, differentiated by their location, structural features and content of enzymes mediating or energizing ion transport. The disruption of the gap junction bonds by connexin mutations and other pathologies leads to an interruption of K+ recirculation pathways. The expression of cochlin and otoraplin, proteins that participate in structural or regulatory functions in the inner ear, suggests more diversity and complexity of the mesenchymal tissues than envisioned previously. The presence of otospiralin, a novel protein found in fibrocytes of spiral limbus, spiral ligament and subepithelial regions of the vestibule, represent a critical finding since that protein has been shown to be essential for the survival of the hair cells and supporting cells of the innerear. Amore profound knowledge and understanding of the function of inner ear fibrocytes will provide a new and promising aetiopathogenic approach to the treatment of innerear disorders (AU)

Pseudoartrosis de acromión tras politraumatismo tratamiento con autoinjerto intercalar y de cresta iliaca / Pseudoarthrosis of acromion due to politrumatism: treatment with autologus graffting intercalar of iliac crest

Las fracturas de la escápula son poco frecuentes una incidencia en torno al 0,4 Y el 1 % de las fracturas que afectan al miembro superior. La fractura de acromion comprende el 7% de las fracturas que afectan a la escápula'. Suelen aparecer en pacientes politraumatizados con lesiones más graves que pueden enmascararlas y post-poner de este modo su diagnóstico y tratamiento. Presentamos un caso clínico de una paciente de 56 años de edad con antecedente de politraumatismo. Que presentaba unas pseudo-artrosis francas del proceso acromial de su hombro derecho con clínica dolorosa y limitación de movimiento.Se trató de manera quirúrgica mediante el aporte de injerto óseo intercalar y fijación mediante placa de osteo-síntesis obteniendo buenos resultados clínico radiológicos a día de hoy. La clínica dolorosa ha desaparecido por completo a día de hoy.

The fractures of the scapula are not very frequent, an incidence around the 0,4 and 1 % of the fractures that affect the upper limb

Pseudoartrosis de acromión tras politraumatismo tratamiento con autoinjerto intercalar y de cresta iliaca / Pseudoarthrosis of acromion due to politrumatism: treatment with autologus graffting intercalar of iliac crest

Las fracturas de la escápula son poco frecuentes una incidencia en torno al 0,4 Y el 1 % de las fracturas que afectan al miembro superior. La fractura de acromion comprende el 7% de las fracturas que afectan a la escápula. Suelen aparecer en pacientes politraumatizados con lesiones más graves que pueden enmascararlas y post-poner de este modo su diagnóstico y tratamiento. Presentamos un caso clínico de una paciente de 56 años de edad con antecedente de politraumatismo. Que presentaba unas pseudo-artrosis francas del proceso acromial de su hombro derecho con clínica dolorosa y limitación de movimiento.Se trató de manera quirúrgica mediante el aporte de injerto óseo intercalar y fijación mediante placa de osteo-síntesis obteniendo buenos resultados clínico radiológicos a día de hoy. La clínica dolorosa ha desaparecido por completo a día de hoy.(AU)

The fractures of the scapula are not very frequent, an incidence around the 0,4 and 1 % of the fractures that affect the upper limb