RESUMO
Cervical damage is the most prevalent type of spinal cord injury clinically, although few preclinical research studies focus on this anatomical region of injury. Here we present a combinatorial therapy composed of a custom-engineered, injectable hydrogel and human induced pluripotent stem cell (iPSC)-derived deep cortical neurons. The biomimetic hydrogel has a modular design that includes a protein-engineered component to allow customization of the cell-adhesive peptide sequence and a synthetic polymer component to allow customization of the gel mechanical properties. In vitro studies with encapsulated iPSC-neurons were used to select a bespoke hydrogel formulation that maintains cell viability and promotes neurite extension. Following injection into the injured cervical spinal cord in a rat contusion model, the hydrogel biodegraded over six weeks without causing any adverse reaction. Compared to cell delivery using saline, the hydrogel significantly improved the reproducibility of cell transplantation and integration into the host tissue. Across three metrics of animal behavior, this combinatorial therapy significantly improved sensorimotor function by six weeks post transplantation. Taken together, these findings demonstrate that design of a combinatorial therapy that includes a gel customized for a specific fate-restricted cell type can induce regeneration in the injured cervical spinal cord.
Assuntos
Medula Cervical , Células-Tronco Pluripotentes Induzidas , Traumatismos da Medula Espinal , Ratos , Humanos , Animais , Hidrogéis/química , Reprodutibilidade dos Testes , Medula Espinal , NeurôniosRESUMO
Knowing precisely where a spacecraft lands on Mars is important for understanding the regional and local context, setting, and the offset between the inertial and cartographic frames. For the InSight spacecraft, the payload of geophysical and environmental sensors also particularly benefits from knowing exactly where the instruments are located. A ~30 cm/pixel image acquired from orbit after landing clearly resolves the lander and the large circular solar panels. This image was carefully georeferenced to a hierarchically generated and coregistered set of decreasing resolution orthoimages and digital elevation models to the established positive east, planetocentric coordinate system. The lander is located at 4.502384°N, 135.623447°E at an elevation of -2,613.426 m with respect to the geoid in Elysium Planitia. Instrument locations (and the magnetometer orientation) are derived by transforming from Instrument Deployment Arm, spacecraft mechanical, and site frames into the cartographic frame. A viewshed created from 1.5 m above the lander and the high-resolution orbital digital elevation model shows the lander is on a shallow regional slope down to the east that reveals crater rims on the east horizon ~400 m and 2.4 km away. A slope up to the north limits the horizon to about 50 m away where three rocks and an eolian bedform are visible on the rim of a degraded crater rim. Azimuths to rocks and craters identified in both surface panoramas and high-resolution orbital images reveal that north in the site frame and the cartographic frame are the same (within 1°).
RESUMO
The nutrition support team at Lucile Salter Packard Children's Hospital at Stanford developed a clinical pathway for infants and children receiving parenteral nutrition (PN). Use of clinical pathways for health care delivery is one way in which clinicians and institutions are responding to pressure from managed care organizations to reduce costs and maintain or improve quality. This pathway was developed to standardize the process for ordering, implementing, and monitoring PN. Specific goals for the pathway are as follows: to decrease the number of patients receiving PN inappropriately, to decrease the duration of PN for those patients who require it, to determine complication rates, and to monitor outcomes of therapy. Such comprehensive monitoring will help identify areas for improvement. By developing and implementing action plans to address these issues, we expect to improve continuously the processes and outcomes associated with PN therapy.
Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Procedimentos Clínicos , Nutrição Parenteral , Equipe de Assistência ao Paciente , Algoritmos , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Avaliação Nutricional , Nutrição Parenteral/métodosRESUMO
Six hundred and twenty-nine cases of viral hepatitis (A, B, and NonA-NonB) were reported among a total of 768,832 United States Navy and Marine Corps personnel during 1984 and 1985 via a passive surveillance system. Cumulative incidence for all three hepatitis types was higher than those reported for the general population at the same time. Hepatitis B was the most common diagnosis within all sex, rank, and race/ethnic description categories. Enlisted medical personnel (hospital corpsmen) had a disproportionately higher incidence of hepatitis B.