12 research outputs found
Neuromorphometric characterization with shape functionals
This work presents a procedure to extract morphological information from
neuronal cells based on the variation of shape functionals as the cell geometry
undergoes a dilation through a wide interval of spatial scales. The targeted
shapes are alpha and beta cat retinal ganglion cells, which are characterized
by different ranges of dendritic field diameter. Image functionals are expected
to act as descriptors of the shape, gathering relevant geometric and
topological features of the complex cell form. We present a comparative study
of classification performance of additive shape descriptors, namely, Minkowski
functionals, and the nonadditive multiscale fractal. We found that the proposed
measures perform efficiently the task of identifying the two main classes alpha
and beta based solely on scale invariant information, while also providing
intraclass morphological assessment
Abnormal white matter microstructure and increased extracellular free-water in the cingulum bundle associated with delusions in chronic schizophrenia
Background: There is growing evidence to suggest that delusions associated with schizophrenia arise from altered structural brain connectivity. The present study investigated whether structural changes in three major fasciculi that interconnect the limbic system â the cingulum bundle, uncinate fasciculus and fornix â are associated with delusions in chronic schizophrenia patients.
Methods: Free-water corrected Diffusion Tensor Imaging was used to investigate the association between delusions and both microstructural changes within these three fasciculi and extracellular changes in the surrounding free-water. Clinical data and diffusion MRI scans were obtained from 28 healthy controls and 86 schizophrenia patients, of whom 34 had present state delusions, 35 had a lifetime history but currently remitted delusions, and 17 had never experienced delusions.
Results: While present state and remitted delusions were found to be associated with reduced free-water corrected fractional anisotropy (FAT) and increased free-water corrected radial diffusivity (RDT) in the cingulum bundle bilaterally, extracellular free-water (FW) in the left cingulum bundle was found to be specifically associated with present state delusions in chronic schizophrenia. No changes were observed in the remaining tracts.
Conclusions: These findings suggest that state and trait delusions in chronic schizophrenia are associated with microstructural processes, such as myelin abnormalities (as indicated by decreased FAT and increased RDT) in the cingulum bundle and that state delusions are additionally associated with extracellular processes such as neuroinflammation or atrophy (as indicated by increased FW) in the left cingulum bundle
Etiologia das infecçÔes intramamĂĄrias em vacas primĂparas no perĂodo pĂłs-parto Etiology of intramammary infections in primiparous cows at postparturition
Foram analisadas 664 amostras de leite de 83 vacas primĂparas da raça Holandesa. As amostras foram colhidas no primeiro e no sĂ©timo dia apĂłs o parto. Das 664 amostras analisadas, 488 (73,50%) foram bacteriologicamente negativas e 176 (26,50%), positivas para microrganismos aerĂłbios. Foi observado um alto Ăndice de mastite clĂnica (20,48%). Os agentes isolados com maior freqĂŒĂȘncia foram os Staphylococcus spp coagulase negativo (64,20%), Staphylococcus spp coagulase positivo (8,52%), Streptococcus spp (7,96%), Actinomyces pyogenes (4,55%), Mycoplasma bovigenitalium (3,40%) e Escherichia coli (2,84%). Foi observado um maior Ăndice de isolamento de patĂłgenos no primeiro dia (17,62%) em relação ao sĂ©timo (8,88%).<br>A total of 664 foremilk samples from 83 Holstein cows were cultured. Quarter samples were collected at parturition and 7 days post the first parturition. From 664 milk samples examined, 488 (73.50%) were bacteriologically negative and 176 (26.50%) were positive. A high incidence (20.48%) of clinical mastitis was observed. The most frequently encountered isolates were coagulase negative staphylococci (64.20%), coagulase positive staphylococci (8.52%), streptococci (7.96%), Actinomyces pyogenes (4.55%), Mycoplasma bovigenitalium (3.40%) and Escherichia coli (2.84%). The frequency of mastitis pathogen isolation was highest at parturition (17.62%) and decreased markedly during the first week (8.88%)