Recent developments in neurobiology make it clear that glia play fundamental and active roles, in the adult and in development. Many hereditary cognitive disorders have been linked to developmental defects, and in at least two cases, Rett Syndrome and Fragile X Mental Retardation, glia are important in pathogenesis. However, most studies of developmental disorders, in particular intellectual disability, focus on neuronal defects. An example is intellectual disability caused by mutations in ACSL4, a metabolic enzyme that conjugates long-chain fatty acids to Coenzyme A (CoA). Depleting ACSL4 in neurons is associated with defects in dendritic spines, a finding replicated in patient tissue, but the etiology of this disorder remains unclear. In a genetic screen to discover genes necessary for visual function, I identified the Drosophila homolog of ACSL4, Acsl, as a gene important for the magnitude of neuronal transmission, and found that it is required in glia. I determined that Acsl is required in a specific subtype of glia in the Drosophila optic lobe, and that depletion of Acsl from this population causes morphological defects. I demonstrated that Acsl is required in development, and that the phenotype can be rescued by human ACSL4. Finally, I discovered that ACSL4 is expressed in astrocytes in the mouse hippocampus. This study is highly significant for understanding glial biology and neurodevelopment. It provides information on the role of glia in development, substantiates a novel role for Acsl in glia, and advances our understanding of the potential role that glia play in the pathogenesis of intellectual disability.

Recent studies have shown elevated neuroinflammation in a large subset of individuals diagnosed with schizophrenia. A pro-inflammatory cytokine, tumor necrosis factor-alpha (TNFα), has been directly linked to this neuroinflammation. This study examined the effects of two TNFα modulators (PD2024 and PD340) produced by our collaborators at P2D Bioscience, Inc., to alleviate auditory sensorimotor gating deficits and reduce microglial cell activation present in the polyinosinic:polycytidylic (Poly I:C) rodent model of schizophrenia. Auditory sensorimotor gating was assessed using prepulse inhibition and microglial activation was examined and quantified using immunohistochemistry and confocal microscopy, respectively. Both PD2024 and PD340 alleviated auditory sensorimotor gating deficits and reduced microglia activation and thereby demonstrated the ability to treat both the behavioral and neuroinflammatory aspects of the disorder. These results are significant and suggest that neural TNFα is a potential pharmacological target for the treatment of schizophrenia.

La inestabilidad de microatélites (MSI) está presente en diferentes tipos tumorales. Generalmente se explica por metilación del promotor de MLH1 o mutaciones germinales en los genes de reparación mismatch repair (MMR) del ADN, causando el conocido síndrome de Lynch. Recientemente, con el cribado universal se ha dado a conocer que un gran porcentaje de tumores con sospecha de síndrome de Lynch, no presentan estas mutaciones. Hasta la fecha, la hipótesis más aceptada para explicar este fenómeno conocido como síndrome Lynch-like, es la doble inactivación de estos genes a nivel somático. Aun así, estos pacientes presentan cáncer colorectal y otros tumores a edades tempranas y en muchos casos, se acompaña de una historia familiar de cáncer colorectal, que sugiere un origen hereditario. Objetivos: Elucitar las bases moleculares responsables de la pérdida de función del sistema MMR en casos de sospecha de Síndrome de Lycnh sin mutaciones germinales en estos genes. Estudio germinal: Identificar nuevas mutaciones germinales en genes reparadores del ADN que puedan estar implicadas en el desarrollo de inestabilidad de microsatélites. Estudio somático: Realizar una caracterización molecular de los tumores con MSI para identificar los eventos moleculares que pueden impactar el comportamiento tumoral y el manejo clínico. Materiales y métodos: Se analizó el exoma germinal de 100 muestras de pacientes Lynch-like y 30 Lynch. Adicionalmente se secuenciaron 37 tumores Lynch-like, 25 Lynch y se utilizó la información de 31 MSI/BRAF del TCGA. Las muestras fueron secuenciadas en Illumina HiSeq y analizadas en un High-performance computer siguiendo los estándares del Yale Center for Genome Analysis (YCGA). Resultados: Estudio germinal: Entre los Lynch-like encontramos 7 Lynch no identificados previamente. El 50% del MSI detectado en Lynch-like podía explicarse por dobles inactivación de los mismos a nivel somático. Además entre los Lynch-like encontramos 15 variantes germinales patogénicas que podían explicar la inestabilidad genética. Dos de ellas con inactivación del otro alelo a nivel somático. Además demostramos que la inactivación de un solo alelo es suficiente para tener un fenotipo deficiente. Estudio somático: no todos los tumores clasificados como MSI por MSI-PCR son presentan esta inestabilidad a nivel global. Al analizar diferentes tumores MSI descubrimos dos clústeres bien diferenciados en base a los perfiles mutacionales detectados. Buscamos mutaciones en genes reparadores y de predisposición al cáncer que pudieran estar marcando esas diferencias en las signatures. Discusión y conclusiones: Estudio germinal: Este estudio confirma el enriquecimiento existente en variantes germinales en los genes reparadores del ADN en pacientes con Síndrome Lynch-like. Variantes en estos genes, conferirían una deficiencia media heredada que promovería y podría inducir una inestabilidad genómica con el paso del tiempo. LA identificación de la variante en RECQL5 como potencial mutación asociada a un fenotipo de cáncer colorrectal familiar. Lynch-like es un grupo heterogéneo a nivel genético, con la característica común de ser MSI. Los tumores Lynch-like pueden ser causados por doble inactivación somática u otros defectos en otros genes reparadores. Además, el grupo incluye Lynch no identificados por los métodos de detección actuales. Estudio somático: Este estudio proporciona un valorable nueva perspectiva en los tumores con deficiencia en el sistema MMR. Muestra la correlación entre los diferentes niveles de MSI global y los perfiles mutacionales y clínicos, lo cual puede tener grandes implicaciones a nivel de diagnóstico y tratamiento de los pacientes.

Hereditary equine regional dermal asthenia (HERDA) is a recessive connective tissue disorder of Quarter Horse lineages. This study correlates previously identified decreases in skin tensile strength in HERDA with abnormal dermal collagen cross linking patterns that are also identified in urine from HERDA horses. Dermal collagen from HERDA horses has significantly less pyridinoline and significantly more deoxypyridinoline than control or carriers. Concentrations of hydroxylysine, the rate limiting substrate for these crosslinks were significantly lower in HERDA versus control and carriers. These characteristics of HERDA skin parallel humans with a similar syndrome of skin fragility, Ehlers Danlos Syndrome TypeVIA. This is the first biochemical evidence explaining the clinical skin fragility that characterizes HERDA and suggests that altered collagen lysine metabolism may be physiologically relevant to the clinical manifestation of HERDA. Evaluations of mature scars indicate that lesion and nonlesioned skin should not be viewed as biologically equivalent in HERDA investigations.

Until the beginning of the 19th century no sharply defined demarcation between Danish on the one hand and German on the other had been possible nor necessary. However, throughout the century the firm belief that Danes and Germans had been fierce enemies from time immemorial in the fight for control over the border region, and specifically over Schleswig, became prevalent. From a Danish perspective, the border between the two parties had always run along the Eider and should continue to do so, whereas the people of Schleswig-Holstein claimed their eternal solidarity and affiliation including the regions further north as far as the course of the Königsau. The close ties in socio-cultural and political terms which had existed between Denmark and Schleswig-Holstein, or else Germany, during medieval and modern times were neglected or ignored. Denmark now sought out and emphasized the closeness to the Scandinavian neighbours instead. The predominant commitment to a vague Nordism, to which the German neighbours had no direct access, became an important part in the concept of the German-Danish border as a kind of protective barrier against the south that continues to have an effect even today, considering the 2016 reintroduced passport controls and the 2019 newly arranged ‘wild boar fence’ along the German-Danish border.

The gut microbiota and its metabolites have vast impacts on the human digestive system, immune system, and health outcomes. Short chain volatile fatty acids (SCVFAs) present in feces can be representative of the interactions of the microbiota present in the gut. Low microbiota diversity in the human gut is highly associated with obesity and adverse health outcomes. Furthermore, the maternal microbiome has a direct impact on neonatal microbiota through various pathways such as environment, skin flora, breast milk composition, and vaginal secretions. This study is aimed to further understand the associations between various factors (maternal adiposity, gestational time, length of life, delivery mode, and race/ethnicity ) and neonatal microbiome and its metabolites, SCFA. Data (pre-pregnancy BMI, gestational time, length of life at time of sample collection, delivery mode, race/ethnicity, SCVFA profiles, fecal fermentation profiles, and 16s rRNA sequences, n=75) was obtained from 75 mother-infant dyads. Qiagen CLC Genomics Workbench was used to process 16s RNA data, generate quantitative and qualitative measures of alpha and beta diversity, and generate an analysis of the composition of microbiomes for differential abundances. Multiple metrics were analyzed for alpha and beta diversity and no significant differences were found for acetic acid (A), propionic acid (P), butyric acid (B), or APB combined. Shannon diversity index, a measure of Alpha diversity, showed no significant difference between groups in each subset. BMI differences were significant for no c-section vs. c-section and Black vs. White race/ethnicity. There were no significant differences found in PERMANOVA, a measure of beta diversity, or found in differential abundances among the groups.

Since the advent of recommendations for placing infants in the supine position during sleep to reduce the incidence of sudden infant death syndrome, clinicians have noted an increase in the frequency of cranial asymmetry due to deformation of suture sections of the infants’ skulls as a result of constant concentrated stress in one area at the back of their head. This specific form of cranial deformation is known as positional plagiocephaly and its rate of occurrence has increased from 0.3% in 8.2% within the past 30 years. Current treatments and methodologies for preventing and correcting positional plagiocephaly such as stretching exercises, bedding pillows, and cranial molding are not optimized for effectiveness and comfort. Literature surrounding the implementation of these methodologies or devices often assesses the relative effectiveness of each treatment through statistical means, or studies complications associated with their use. There is a lack of quantified mechanical analysis for determining the effectiveness of each treatment or engineered solutions. In this study, a finite element model was created and validated to study the effect of wearing a cranial helmet, as the most effective non-surgical device for treatment of positional plagiocephaly, on reducing concentrated stress from the back of the baby’s head during sleep. The results from this model were then compared to two other finite element models with a healthy baby sleeping in supine position on a pillow, and a patient diagnosed with a severe case of positional plagiocephaly sleeping on the flat side of his head in supine position. The geometries representing the head of the babies in these models are the refined 3D laser-scanned file of a patient’s head contour at Hanger Clinic as well as the cavity inside the cranial helmet that was used for treatment of the baby. After successfully assigning section and contact properties to different regions of the models, applying proper loading and boundary conditions, and performing mesh convergence studies for each of the three models, the average Von Mises stress values of each of the 13 different suture segments of each model were summarized in tables and evaluated using mathematical and qualitative methods. The stress value data obtained from different suture regions of the model with the cranial helmet resulted in the smallest standard deviation among all three populations which supports that wearing the cranial helmet helps to reduce stress concentrations. Use of the cranial helmet during sleep also showed a significant decrease of the average Von Mises stress within the posterior fontanelle by 90% compared to the healthy baby sleeping in supine position and 73.4% compared to the deformed head sleeping on the flat surface of the head. The major limitations of this study are correlated with the simplifying assumptions and geometries in generating and validating the models. Future studies need to focus on overcoming these limitations and generating more complex models using a similar approach. The methods used in this study and the results obtained from the models can serve as a basis for future development of engineered solutions that are more effective than the existing solutions in the market and reduce the side-effects and complications associated with their use.

No description available.

No description available.

Friedreich's ataxia (FRDA) is the most prevalent inherited ataxia, affecting one in every 50,000 individuals in the United States. This hereditary condition is caused by an abnormal GAA trinucleotide repeat expansion within the first intron of the frataxin gene resulting in decreased levels of the frataxin protein (FXN). Insufficient cellular frataxin levels results in iron accumulation, increased reactive oxygen species production and mitochondrial dysfunction. Tissues most heavily impacted are those most dependent on oxidative phosphorylation as an energy source and include the nervous system and muscle tissue. This is evident in the clinical phenotype which includes muscle weakness, ataxia, neurodegeneration and cardiomyopathy. However, there has been a lack of data regarding the cell type specific contributions in FRDA pathogenesis. We generated a cohort of induced pluripotent stem cells (iPSCs) consisting of FRDA patient lines, CRISPR-Cas9 edited controls, carriers and non-related controls. Our preliminary data identified a hyperinflammatory microglial phenotype with extensive defects in mitochondrial function; since microglia are the primary innate immune cell of the brain, we hypothesized microglia may decrease neuronal viability which contributes to FRDA pathology. To investigate this, the iPSC cohort was utilized to generate microglia (iMGs) and neurons to better understand microglia-mediated neurodegeneration and how this contributes to pathology. An in vitro co-culture model composed of neurons, astrocytes and microglia was employed to better understand microglia-neuronal communication in FRDA. Healthy neurons co-cultured with FRDA iMG or with FRDA iMG-conditioned media demonstrated higher incidences of caspase-3 mediated apoptosis. These findings were recapitulated in vivo as xenotransplantation of FRDA microglia progenitors into a murine model resulted in reduced Purkinje cell survival in the cerebellum. Previous research has demonstrated the therapeutic potential of wildtype microglia to rescue the FRDA phenotype in the Y8GR mouse model of FRDA. To further explore the potential mechanisms behind this rescue, the delivery of mitochondria and FXN to FRDA microglia and neurons was investigated. CRISPR-Cas9 edited microglia demonstrated transfer of healthy mitochondria to FRDA microglia and neurons in an in vitro co-culture model. To investigate the transfer of frataxin protein, an FRDA iPSC line was transduced with an FXN-GFP lentivirus. Restoring FXN expression was demonstrated to rescue the FRDA microglial morphological phenotype. FXN-GFP microglia demonstrated transfer of frataxin protein to FRDA microglia suggesting the potential role of microglia as a therapeutic vehicle in FRDA. Together these findings show that FRDA microglia have a deleterious effect on neuronal viability, while healthy microglia may work as a therapeutic vehicle through the delivery of mitochondria and frataxin to FRDA cells.