Assessment of Angiogenesis and Cell Survivability of an Inkjet Bioprinted Biological Implant in an Animal Model.

The rapidly growing field of tissue engineering hopes to soon address the shortage of transplantable tissues, allowing for precise control and fabrication that could be made for each specific patient. The protocols currently in place to print large-scale tissues have yet to address the main challenge of nutritional deficiencies in the central areas of the engineered tissue, causing necrosis deep within and rendering it ineffective. Bioprinted microvasculature has been proposed to encourage angiogenesis and facilitate the mobility of oxygen and nutrients throughout the engineered tissue. An implant made via an inkjet printing process containing human microvascular endothelial cells was placed in both B17-SCID and NSG-SGM3 animal models to determine the rate of angiogenesis and degree of cell survival. The implantable tissues were made using a combination of alginate and gelatin type B; all implants were printed via previously published procedures using a modified HP inkjet printer. Histopathological results show a dramatic increase in the average microvasculature formation for mice that received the printed constructs within the implant area when compared to the manual and control implants, indicating inkjet bioprinting technology can be effectively used for vascularization of engineered tissues.

A Comparative Study in the Printability of a Bioink and 3D Models Across Two Bioprinting Platforms.

In this study, we used an alginate-gelatin bioink to design and print 3D constructs with lattice, honeycomb and fibrous bundle patterns. These designs were printed using a small-scale laboratory printer, at first and later translated to a larger scale, high throughput-printing platform. A comparative analysis of the structures printed using two dissimilar platforms using gross morphologic evaluation, scanning electron microscopy and swelling assay confirmed our hypothesis that a design printed using a small-scale laboratory bioprinter for optimization of bioink composition and printing parameters can be successfully translated into a large scale-printing platform for high throughput printing of constructs. Since the designs for printing were implemented using a software which was common across both printers, this endpoint was feasible. The only difference in printing parameters resulted from variation in extrusion pressure which was due to a significant difference in barrel size used across both printers (3 ml versus 30 ml), while all other parameters stayed the same. Although the scaffolds were not bioprinted with cells, in future we will investigate how cell viability can be differentially regulated by the variation of extrusion pressure across both platforms.

[Glutamate increase in the associative striatum in schizophrenia: a longitudinal magnetic resonance spectroscopy preliminary study]. / Incremento del glutamato en el estriado de asociación en esquizofrenia. Resultados preliminares de un estudio longitudinal con espectroscopia con resonancia magnética.

OBJECTIVE: To compare glutamate levels (Glu) found in the dorsal-caudate nucleus (a dopamine rich region) and in the cerebellum (a low dopamine region) among: 1) schizophrenia patients undergoing an acute psychotic episode, 2) after receiving antidopaminergic treatment (Risperidone), and 3) healthy controls. METHODS: Fourteen drug-free patients with schizophrenia and fourteen healthy controls were included. Patients underwent two proton magnetic resonance spectroscopy (1H-MRS) studies, one prior to treatment and the second after 6-weeks of daily Risperidone treatment. Controls underwent one 1H-MRS study. Glutamate levels were normalized according to the relative concentration of Creatine (Cr). RESULTS: The dorsal-caudate nucleus among schizophrenia patients showed higher levels of Glu/Cr during the drug-free condition (t = -2.16, p = 0.03) and after antipsychotic treatment (t = 2.12, p = 0.04) compared with controls. No difference was observed in the cerebellum between the drug-free, post-treatment and controls conditions. CONCLUSIONS: Our results suggest that the Glu increase observed in the dorsal-caudate in schizophrenia is illness-mediated and does not change after 6-weeks of antipsychotic treatment. Moreover, the lack of change detected in the cerebellum suggests that the Glu increase in schizophrenia is not ubiquitous within the brain and that may be associated with dopamine target regions.

Incremento del glutamato en el estriado de asociación en esquizofrenia. Resultados preliminares de un estudio longitudinal con espectroscopia con resonancia magnética / Glutamate increase in the associative striatum in schizophrenia: a longitudinal magnetic resonance spectroscopy preliminary study

Objetivo: Comparar los niveles de glutamato en el núcleo caudado dorsal, región rica en dopamina, y el cerebelo, región pobre en dopamina, en pacientes con esquizofrenia, durante un episodio psicótico agudo, después de recibir tratamiento antidopaminérgico (risperidona) y en controles sanos. Métodos: Se incluyeron 14 pacientes con esquizofrenia aguda sin tratamiento y 14 controles sanos. A los pacientes se les realizaron dos estudios de espectroscopia por resonancia magnética de protones (ERM1H). El primero antes de tratamiento y el segundo a las seis semanas de tratamiento efectivo. Los controles fueron evaluados en una ocasión. Los niveles de glutamato fueron normalizados con la concentración de creatina. Resultados: Los niveles de glutamato/creatina fueron mayores en el caudado dorsal de los pacientes previo a tratamiento (t=-2.16, p=0.03) y después del tratamiento en comparación con los controles (t=2.12, p=0.04). Los niveles de glutamato en el cerebelo no cambiaron con el tratamiento y fueron iguales a los controles. Conclusiones: Nuestros resultados indican que el incremento delglutamato en el caudado dorsal se encuentra en relación con la enfermedad y no cambia después de seis semanas de tratamiento antipsicótico efectivo. Más aún, la ausencia de diferencias en el cerebelo sugiere que el incremento del glutamato presente en la esquizofrenia se podría relacionar a regiones con abundante inervación dopaminérgica.

OBJECTIVE: To compare glutamate levels (Glu) found in the dorsal-caudate nucleus (a dopamine rich region) and in the cerebellum (a low dopamine region) among: 1) schizophrenia patients undergoing an acute psychotic episode, 2) after receiving antidopaminergic treatment (Risperidone), and 3) healthy controls. METHODS: Fourteen drug-free patients with schizophrenia and fourteen healthy controls were included. Patients underwent two proton magnetic resonance spectroscopy (1H-MRS) studies, one prior to treatment and the second after 6-weeks of daily Risperidone treatment. Controls underwent one 1H-MRS study. Glutamate levels were normalized according to the relative concentration of Creatine (Cr). RESULTS: The dorsal-caudate nucleus among schizophrenia patients showed higher levels of Glu/Cr during the drug-free condition (t = -2.16, p = 0.03) and after antipsychotic treatment (t = 2.12, p = 0.04) compared with controls. No difference was observed in the cerebellum between the drug-free, post-treatment and controls conditions. CONCLUSIONS: Our results suggest that the Glu increase observed in the dorsal-caudate in schizophrenia is illness-mediated and does not change after 6-weeks of antipsychotic treatment. Moreover, the lack of change detected in the cerebellum suggests that the Glu increase in schizophrenia is not ubiquitous within the brain and that may be associated with dopamine target regions.

Bacteriemia por leuconostoc citreum en trauma craneoencefálico grave por proyectil de arma de fuego / Leuconostoc citreum bacteremia in severe head trauma by firearm missile

Se presenta el caso de un paciente con trauma craneoencefálico grave por proyectil de arma de fuego a quien se le documentó en el curso de su enfermedadbacteriemia por Leuconostoc citreum. Se presenta y se discute la evolución del paciente y su manejo antibiótico. Se discute la probable vía de entrada del germen al torrente sanguíneo y se revisa la literatura mundial. Lo inusual del caso motivó a los autores a publicarlo.

A case of severe head trauma by firearm missilesis presented; bacteremia by Leuconostoc citreumwas documented in the course of the disease. Theclinical course of the patient and the antibiotictreatment are presented and discussed. The pro-bable route of contamination and the entrance ofthe bacteria into the blood stream are discussedand the worldwide literature is reviewed. Therarity of this case encouraged the authors topublish it