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BEVERLY HILLS, CA, United States

Pais V.,National Institute of Neurology and Neurovascular Diseases | Danaila L.,National Institute of Neurology and Neurovascular Diseases | Pais E.,Spectral Molecular Imaging, Inc.
Journal of Neurosurgical Sciences | Year: 2014

Aim. This cytohistopathological study was performed for a better knowledge of phenotypes derived from pluripotent stem cells, as well as for precise location of stem cells within the vascular niche in the brain. Methods. We used light and transmission electron microscopy to demonstrate the presence of stem cells in the vascular wall of microvessels in the cerebral and cerebellar cortex, pia mater (considered by us a cordocytic-vascular tissue), adventitia of larger cortical arteries and veins, and around vessels. We investigated multiple vascular segments and brain tissue in a variety of clinical cases, such as cerebral tumors, cerebrovascular malformations, thromboses in the carotid system, and direct laceration. Results. Our morphological and ultrastructural observations pointed out many changing phenotypes, as well as cell interrelationships within the vascular niche, both for repair processes when cordocytes cooperate with mesenchymal stem cells, and pathological processes such as atherogenesis, tumorigenesis, and neurotrauma. Our results underlie the important roles of cordocytes in their interrelations with precursor/stem cells in the arterial adventitia. Conclusion. The cells derived from pluripotent stem cells along different lineages have had different phenotypes as they derived from hematopoietic stem cells or mesenchymal stem cells, with or without epigenetic deregulations or depending on different microen-vironments. Cell interactions, phenotypes, and underlying mechanisms, as well as biological responses to different small molecules or compounds, remain to be determined by future molecular insights within the vascular niche. Source

Pais V.,National Institute of Neurology and Neurovascular Diseases | Danaila L.,National Institute of Neurology and Neurovascular Diseases | Pais E.,Spectral Molecular Imaging, Inc.
Ultrastructural Pathology | Year: 2013

This study is based on data analysis by light and transmission electron microscopy of the surgical cases in cerebral tumors, cerebrovascular malformations, thromboses in the carotid system, and other injuries such as perivascular hemorrhage. We examined cortical arteries and veins, perivascular areas with old hematic masses, vasculogenic foci, and broken large vessels. We identified, characterized, and compared both undifferentiated cells and well-differentiated cordocytes within periadventitial areas where these cells cooperate very well with precursor/stem cells to perform vital functions for cerebral vasculature with immediate effect on brain parenchyma. This useful cellular cooperation was observed by serial sections pointing out the main role of cordocytes during the entire process of collateral vessel formation after thrombosis and, respectively, in vascular wall repair after ruptures. This is the first cytohistopathological study which illustrates and explains some facets of cordocytes-stem cells cooperation around the vessels of human brain with emphasis on the fundamental role of cordocytes in response to vascular injuries. Our pioneering study will be completed for both basic science and modern medical care by further studies. © 2013 Informa Healthcare USA, Inc. All rights reserved. Source

Iskovich S.,Center for Stem Cell Research | Stein J.,Bone Marrow Transplantation Unit | Yaniv I.,Bone Marrow Transplantation Unit | Farkas D.L.,Spectral Molecular Imaging, Inc. | Askenasy N.,Center for Stem Cell Research
Stem Cells and Development | Year: 2011

The contribution of stem cells derived from adult tissues to the recovery of pancreatic islets from chemical injury is controversial. Analysis of nonhematopoietic differentiation of bone marrow-derived cells has yielded positive and negative results under different experimental conditions. Using the smallest subset of bone marrow cells lacking immuno-hematopoietic lineage markers, we have detected incorporation and conversion into insulin-producing cells. Donor cells identified by genomic markers silence green fluorescent protein (GFP) expression as a feature of differentiation, in parallel to expressing PDX-1 and proinsulin. Here we elaborate potential experimental difficulties that might result in false-negative results. The use of GFP as a reporter protein is suboptimal for differentiation experiments: (a) the bone marrow of GFP donors partially expresses the reporter protein, (b) differentiating bone marrow cells silence GFP expression, and (c) the endocrine pancreas is constitutively negative for GFP. In addition, design of the experiments, data analysis, and interpretation encounter numerous objective and subjective difficulties. Rigorous evaluation under optimized experimental conditions confirms the capacity of adult bone marrow-derived stem cells to adopt endocrine developmental traits, and demonstrates that GFP downregulation and silencing is a feature of differentiation. © Copyright 2011, Mary Ann Liebert, Inc. 2011. Source

Spectral Molecular Imaging, Inc. | Date: 2014-10-03

A solid state detection system includes a degenerate photo-parametric amplifier (PPA), wherein the PPA comprises a photo diode, and a periodically pulsed light source, wherein the photo-parametric, amplifier (PPA) is synchronized to the pulsed light source with a phase locked loop that generates a pump waveform for the PPA at twice the frequency of the excitation pulse rate.

Agency: Department of Health and Human Services | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 209.94K | Year: 2014

DESCRIPTION (provided by applicant): Melanoma, the fastest growing cancer worldwide, kills more than one person every hour in the United States and costs more than 2.4 billion per year. Yet, if detected at an early stage, it can be easily cured with a tenfold improvement in survival rate and a hundredfold reduction in treatment cost. Current methods have not yielded the breakthroughs needed, either because they are too simple (visual examination of skin, with or with- out digital imaging) or because the required high sensitivity comes at the expense of lowered specificity, even in emerging advanced methods. What is necessary to address these unmet needs is a more sophisticated approach. We propose such an approach, based on analysis of the current state-of-the-art in melanoma diagnosis and feedback from clinicians, as well as concepts from the well-established field of risk management. We concluded that a combination of several imaging methods is needed, brought together onto the same instrument, in a

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