ABSTRACT
Scaffold-based tissue engineering provides cells with an engineered matrix to enhance and direct cell attachment, proliferation and differentiation. One critical limitation to current tissue engineering approaches is the inability to create densely populated constructs thicker than a few 100 µm. We hypothesized that development of porous, channeled scaffolds would increase cell density and uniformity of their spatial distribution through scaffold channel perfusion. Patterned polyurethane sheets were fabricated using a sprayed phase separation technique and laminated together to form 1.5 mm thick channeled scaffolds. Hydraulic permeability testing confirmed the presence of functional channels throughout the multilaminate construct. A continuous flow bioreactor was used to perfuse the construct with medium during the culture period. Cross-sectional cell densities and spatial uniformities were measured in channeled and nonchanneled scaffolds under different seeding and culture conditions. Channeled scaffolds were found to have higher densities of human mesenchymal stem cells than nonchanneled samples. Perfused scaffolds had more uniform spatial distribution of cells within the scaffold compared to statically cultured scaffolds. In conclusion, we have shown the channeled scaffolds to be a promising approach toward creating thick tissue-engineered constructs.
Subject(s)
Bioreactors , Cell Culture Techniques/instrumentation , Cell Culture Techniques/methods , Mesenchymal Stem Cells/cytology , Tissue Engineering/instrumentation , Tissue Engineering/methods , Tissue Scaffolds , Cells, Cultured , Humans , Perfusion/methods , Polyurethanes/chemistrySubject(s)
Malpractice , Psychiatric Nursing , Employee Discipline , Ethics, Medical , Humans , United KingdomSubject(s)
Dementia, Vascular/diagnosis , Aged , Alzheimer Disease/diagnosis , Alzheimer Disease/psychology , Comorbidity , Dementia, Vascular/psychology , Geriatric Assessment/statistics & numerical data , Humans , Neuropsychological Tests/statistics & numerical data , Psychometrics , Reproducibility of ResultsABSTRACT
We describe two cases of Binswanger's disease of pre-senile onset which presented with affective and psychotic symptoms well before the appearance of cognitive deterioration and neurological signs, initially evading an accurate diagnosis. Psychiatrists should be aware of white matter disease and its role in the pathogenesis of psychiatric illness. Particular attention should be given to a history of hypertension as a risk factor in the early identification of these cases.
ABSTRACT
Tests of word and face processing were given to patients with complex partial epilepsy focussed on the left or right temporal lobe, and to non-epileptic control subjects. The left TLE group showed the greatest impairment on object naming and on reading tests, but the right TLE group also showed a lesser impairment relative to the normal control subjects on both tests. The right TLE group was selectively impaired on distinguishing famous from non-famous faces while the left TLE group was impaired at naming famous faces they had successfully recognized as familiar. There was no significant difference between the three groups on recognition memory for words. The implications of the results for theories of the role of the temporal lobes in word and face processing, and the possible neural mechanisms responsible for the deficits in TLE patients, are discussed.