Essential role for PDGF signaling in ophthalmic trigeminal placode induction

Much of the peripheral nervous system of the head is derived from ectodermal thickenings, called placodes, that delaminate or invaginate to form cranial ganglia and sense organs. The trigeminal ganglion, which arises lateral to the midbrain, forms via interactions between the neural tube and adjacent ectoderm. This induction triggers expression of Pax3, ingression of placode cells and their differentiation into neurons. However, the molecular nature of the underlying signals remains unknown. Here, we investigate the role of PDGF signaling in ophthalmic trigeminal placode induction. By in situ hybridization, PDGF receptor β is expressed in the cranial ectoderm at the time of trigeminal placode formation, with the ligand PDGFD expressed in the midbrain neural folds. Blocking PDGF signaling in vitro results in a dose-dependent abrogation of Pax3 expression in recombinants of quail ectoderm with chick neural tube that recapitulate placode induction. In ovo microinjection of PDGF inhibitor causes a similar loss of Pax3 as well as the later placodal marker, CD151, and failure of neuronal differentiation. Conversely, microinjection of exogenous PDGFD increases the number of Pax3+ cells in the trigeminal placode and neurons in the condensing ganglia. Our results provide the first evidence for a signaling pathway involved in ophthalmic (opV) trigeminal placode induction

The Photographic Insane

Le célèbre essai de Bazin concernant l'identification de la photographie en fonction de son sujet relevait des liens des premières photographies avec les expérimentations des sciences humaines (la psychiatrie). Contrairement à cette tendance l'auteure développe, dans ce texte, le point de vue selon lequel la perception est reliée à un processus conceptuel. Cet article constitue une courte examination de ce que l'auteure appelle the photographie insane et illustre comment les images de la folie utilisent et demandent pour leur interprétation une construction « schématique » particulière et partagée culturellement.Bazin's famous essay touting the photograph's identicality with its subject was precedented by photography's early relation to empirical investigation in the human sciences (the psychiatry). Contrary to this, what this author wishes to reinforce in this paper is that perception is constructed and integrally bound up with conceptual processes. This paper thus constitutes a short examination of what this author calls the "Photographic Insane," and illustrates how images of madness use, and require for their interpretation, a particular, and culturally shared "schematic" framework

Microfluidic Capture and Quantification of HIV

Once a patient is diagnosed as HIV-positive, tests of viral load (the concentration of virus circulating in the blood) are performed routinely in order to monitor disease progression and ensure treatment effectiveness. Currently, there is no procedure to measure viral load in a point-of-care setting. It often takes upwards of two weeks to receive a patient’s viral load results from central facilities, making it difficult for doctors to make treatment decisions or adjust medication in the case of drug resistance. Microfluidic technology offers the ability to analyze small sample volumes, encouraging the development of point-of-care systems for viral diagnostics. A microfluidic viral load analyzer needs to separate the HIV virions from plasma and quantify the targets. The small size of virions limits the use of traditional, flat-bed, immunoaffinity microfluidic devices. Thus, here we validate the effectiveness of a nanoporous filtration matrix to isolate pseudo HIV virions from a solution [1]. Adapting the methods of da la Escosura and Muniz, virions are tagged with gold nanoparticles, and the virion-gold complexes are augmented with silver deposition, increasing the volume that the complexes occupy within the capture membrane [2]. These aggregates block flow of an ionic solution through the membrane pores. The reduction of ion flow as viral capture increases can be quantified through cyclic voltammetric analysis. Initial experiments show a correlation between a decrease in peak current and an increase in simulated viral load (n=4, R2=0.934). This system, once optimized, has the potential to perform viral load quantification in a point-of-care setting. 1. Surawathanawises, Krissada. “Polymeric Nanoporous Structures Integrated into Microfluidic Device for HIV Detection,” PhD Dissertation, Lehigh University, Bethlehem, PA, 2014. 2. de la Escosura-Muniz, A.; Merkoci, A. “A Nanochannel/Nanoparticle-Based Filtering and Sensing Platform for Direct Detection of a Cancer Biomarker in Blood,” Small, 2011.https://preserve.lehigh.edu/undergrad-scholarship-freed-posters/1007/thumbnail.jp

Molecular and tissue interactions governing induction of cranial ectodermal placodes

Whereas neural crest cells are the source of the peripheral nervous system in the trunk of vertebrates, the “ectodermal placodes,” together with neural crest, form the peripheral nervous system of the head. Cranial ectodermal placodes are thickenings in the ectoderm that subsequently ingress or invaginate to make important contributions to cranial ganglia, including epibranchial and trigeminal ganglia, and sensory structures, the ear, nose, lens, and adenohypophysis. Recent studies have uncovered a number of molecular signals mediating induction and differentiation of placodal cells. Here, we described recent advances in understanding the tissue interactions and signals underlying induction and neurogenesis of placodes, with emphasis on the trigeminal and epibranchial. Important roles of Fibroblast Growth Factors, Platelet Derived Growth Factors, Sonic Hedgehog, TGFβ superfamily members, and Wnts are discussed

Birth of ophthalmic trigeminal neurons initiates early in the placodal ectoderm

The largest of the cranial ganglia, the trigeminal ganglion, relays cutaneous sensations of the head to the central nervous system. Its sensory neurons have a dual origin from both ectodermal placodes and neural crest. Here, we show that the birth of neurons derived from the chick ophthalmic trigeminal placode begins prior to their ingression (HH11), as early as HH8, and considerably earlier than previously suspected (HH16). Furthermore, cells exiting the cell cycle shortly thereafter express the ophthalmic trigeminal placode marker Pax3 (HH9). At HH11, these postmitotic Pax3+ placode cells begin to express the pan-neuronal marker neurofilament while still in the ectoderm. Analysis of the ectodermal origin and distribution of these early postmitotic neurons reveals that the ophthalmic placode extends further rostrally than anticipated, contributing to neurons that reside in and make a significant contribution to the ophthalmic trigeminal nerve. These data redefine the timing and extent of neuron formation from the ophthalmic trigeminal placode

The Seven Words of the Virgin: Identifying Change in the Discourse Context of the Concept of Virginity in Early Modern English

No abstract available

Salish Sea Initiative Interactive Map

The Salish Sea Initiative (SSI) is a Government of Canada, Trans Mountain Expansion (TMX) Accommodation Measure designed to respond to First Nations concerns about the potential environmental impacts of human activities on coastal and marine ecosystems in the Salish Sea. Led by Fisheries and Oceans Canada, the SSI aims to support the capacity building of eligible First Nations within and around the Salish Sea to plan, develop and conduct marine stewardship activities, including environmental monitoring, traditional use studies, and cumulative effects assessments. Thirty-three First Nations are eligible to participate in SSI and the initiative runs until March 2024. A key component of the SSI is the co-development of the SSI Interactive Map (SSIM). The SSIM is a user-friendly, decision support tool that displays data layers of natural marine environmental components, stressors and Indigenous cultural components. The purpose of the map is to provide a platform for SSI participants to visualize valued components (VCs) and other information that will be useful for project planning, implementation of marine stewardship work and cumulative effects assessments. The map is associated with a data catalogue and portal and functions are being created to enable data analysis. The map also serves as a communication tool to host conversations between SSI participants and between SSI participants and the Government of Canada. Enhanced communication capabilities provide support for project planning and coordination, the creation of partnerships, as well as a shared platform for inter-generational knowledge transfer opportunities within communities. The purpose of this presentation is to outline the background and process associated with the SSIM creation and to provide a demonstration to show the work completed to date. We will also highlight future actions to be taken for map enhancement

Exploring how practitioners support and protect adults at risk of harm in the light of the Adult Support and Protection (Scotland) Act 2007

This was a joint academic and practitioner research project that interviewed practitioners and people about their experience of assessment and intervention under the Adult Support and Protection (Scotland) Act 2007. Findings include: the complex and interconnected nature of harm, the value of skilled and open minded practitioners, the need to build and maintain respectful relationships; that thresholds not as clear cut as we might like them to be, protecting means supporting, interagency work was variable in its quality and opportunities for justice through court might still be limite

The Sad State of Healthcare in New Mexico: Healthcare Worker Suicide in New Mexico 2004-2005

THE SAD STATE OF HEALTH CARE IN NEW MEXICO: HEATHCARE WORKER SUICIDE IN NEW MEXICO 2004-2005. KL Bradley*, KD Martinez*, MB Barry**, S Lathrop**, K Fraser***, and K Peters**** * University of New Mexico School of Medicine, Albuquerque, NM, ** New Mexico Office of the Medical Investigator, Albuquerque, NM, *** University of New Mexico School of Medicine, Department of Psychiatry, Albuquerque, NM, **** New Mexico Bureau of Vital Records and Health Statistics, Santa Fe, NM PURPOSE. To determine if there is a statistically significant relationship between suicide and the healthcare occupations in New Mexico for the years 2004-2005. METHODS. We collected suicide and occupational data from the New Mexico Office of the Medical Investigator and the N.M. Bureau of Vital Records and Health Statistics for the years 2004-2005. Other data collected included race, age, veteran status, county of occurrence and residence, location, method, presence of suicide note, toxicology, and psychiatric, medical and other risk factors. Statistical analysis was performed on the data collected. RESULTS. Our database included 658 suicides, including 34 healthcare worker suicides during this two-year period. The suicide rate for healthcare workers (HCWs) in 2004 was higher than the suicide rate of the New Mexico adult population. The suicide rate for HCWs in 2005 was lower than that of the New Mexico adult population. There were significantly more women among the healthcare workers who committed suicide than among the non-healthcare workers. The most commonly represented healthcare professionals among the HCWs who committed suicide were: Nurses, Home Health Aides, Obstetrician/Gynecologists, Laboratory Technicians, Social Workers, and Medical Assistants. Healthcare workers who committed suicide in New Mexico in 2004 and 2005 were 3.7 times more likely to commit suicide by ingesting or injecting medication than the non-healthcare workers who committed suicide during this time frame. CONCLUSION. This study demonstrates that healthcare workers, particularly females, had a higher rate of suicide that the NM adult population in 2004, but not it 2005. Thus, we cannot comment on a trend at this time. Further investigation would be useful in determining the presence of a trend and guiding prevention efforts