scholarly journals Imaging brain structure and function, infection and gene expression in the body using light

1997 ◽  
Vol 352 (1354) ◽  
pp. 755-761 ◽  
Author(s):  
David A. Benaron ◽  
Pamela R. Contag ◽  
Christopher H. Contag
Keyword(s):  
Gene Expression ◽  
Brain Function ◽  
The Body ◽  
Low Light ◽  
Non Invasive ◽  
Positron Emission ◽  
Brain Structure And Function ◽  
Imaging Of Infection ◽  
And Function

Light can be used to probe the function and structure of human tissues. We have been exploring two distinct methods: (i) externally emitting light into tissue and measuring the transmitted light to characterize a region through which the light has passed, and (ii) internally generating light within tissue and using the radiated light as a quantitative homing beacon. The emitted–light approach falls within the domain of spectroscopy, and has allowed for imaging of intracranial haemorrhage in newborns and of brain function in adults. The generated–light approach is conceptually parallel to positron emission tomography (PET) or nuclear medicine scanning, and has allowed for real–time, non–invasive monitoring and imaging of infection and gene expression in vivo using low–light cameras and ordinary lenses. In this paper, we discuss recent results and speculate on the applications of such techniques.

Functional characterization of human brown adipose tissue metabolism

2020 ◽  
Vol 477 (7) ◽  
pp. 1261-1286 ◽  
Author(s):  
Marie Anne Richard ◽  
Hannah Pallubinsky ◽  
Denis P. Blondin
Keyword(s):  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
Functional Characterization ◽  
Human Infants ◽  
Positron Emission ◽  
Brown Adipose ◽  
Treatment Of Obesity ◽  
And Function

Brown adipose tissue (BAT) has long been described according to its histological features as a multilocular, lipid-containing tissue, light brown in color, that is also responsive to the cold and found especially in hibernating mammals and human infants. Its presence in both hibernators and human infants, combined with its function as a heat-generating organ, raised many questions about its role in humans. Early characterizations of the tissue in humans focused on its progressive atrophy with age and its apparent importance for cold-exposed workers. However, the use of positron emission tomography (PET) with the glucose tracer [18F]fluorodeoxyglucose ([18F]FDG) made it possible to begin characterizing the possible function of BAT in adult humans, and whether it could play a role in the prevention or treatment of obesity and type 2 diabetes (T2D). This review focuses on the in vivo functional characterization of human BAT, the methodological approaches applied to examine these features and addresses critical gaps that remain in moving the field forward. Specifically, we describe the anatomical and biomolecular features of human BAT, the modalities and applications of non-invasive tools such as PET and magnetic resonance imaging coupled with spectroscopy (MRI/MRS) to study BAT morphology and function in vivo, and finally describe the functional characteristics of human BAT that have only been possible through the development and application of such tools.

scholarly journals In Vivo Imaging of Biodegradable Implants and Related Tissue Biomarkers

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2348
Author(s):  
Leon Riehakainen ◽  
Chiara Cavallini ◽  
Paolo Armanetti ◽  
Daniele Panetta ◽  
Davide Caramella ◽  
...  
Keyword(s):  
Imaging Modality ◽  
Imaging Techniques ◽  
Special Focus ◽  
Tissue Remodelling ◽  
Biodegradable Implant ◽  
Advantages And Disadvantages ◽  
Non Invasive ◽  
Positron Emission ◽  
Longitudinal Imaging

Non-invasive longitudinal imaging of osseointegration of bone implants is essential to ensure a comprehensive, physical and biochemical understanding of the processes related to a successful implant integration and its long-term clinical outcome. This study critically reviews the present imaging techniques that may play a role to assess the initial stability, bone quality and quantity, associated tissue remodelling dependent on implanted material, implantation site (surrounding tissues and placement depth), and biomarkers that may be targeted. An updated list of biodegradable implant materials that have been reported in the literature, from metal, polymer and ceramic categories, is provided with reference to the use of specific imaging modalities (computed tomography, positron emission tomography, ultrasound, photoacoustic and magnetic resonance imaging) suitable for longitudinal and non-invasive imaging in humans. The advantages and disadvantages of the single imaging modality are discussed with a special focus on preclinical imaging for biodegradable implant research. Indeed, the investigation of a new implant commonly requires histological examination, which is invasive and does not allow longitudinal studies, thus requiring a large number of animals for preclinical testing. For this reason, an update of the multimodal and multi-parametric imaging capabilities will be here presented with a specific focus on modern biomaterial research.

In vivo assessment of adenoviral vector-mediated gene expression of dopamine D2 receptors in the rat striatum by positron emission tomography

Synapse ◽  
2002 ◽  
Vol 43 (3) ◽  
pp. 195-200 ◽  
Author(s):  
Hiroyuki Umegaki ◽  
Kiichi Ishiwata ◽  
Osamu Ogawa ◽  
Donald K. Ingram ◽  
George S. Roth ◽  
...  
Keyword(s):  
Gene Expression ◽  
Positron Emission Tomography ◽  
Adenoviral Vector ◽  
D2 Receptors ◽  
Dopamine D2 Receptors ◽  
Emission Tomography ◽  
Rat Striatum ◽  
Positron Emission ◽  
In Vivo Assessment

scholarly journals Cre/lox-assisted non-invasive in vivo tracking of specific cell populations by positron emission tomography

2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Martin Thunemann ◽  
Barbara F. Schörg ◽  
Susanne Feil ◽  
Yun Lin ◽  
Jakob Voelkl ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Emission Tomography ◽  
Cell Populations ◽  
Specific Cell ◽  
Non Invasive ◽  
Positron Emission

scholarly journals Non-invasive imaging of the coronary arteries

2018 ◽  
Vol 40 (29) ◽  
pp. 2444-2454 ◽  
Author(s):  
Philip D Adamson ◽  
David E Newby
Keyword(s):  
Coronary Arteries ◽  
Randomized Clinical Trials ◽  
Rapid Development ◽  
Current Status ◽  
Future Research ◽  
Research Perspective ◽  
Non Invasive ◽  
Positron Emission ◽  
Prognostic Stratification

Abstract Non-invasive imaging of the coronary arteries is an enterprise in rapid development. From the research perspective, there is great demand for in vivo techniques that can reliably identify features of high-risk plaque that may offer insight into pathophysiological processes and act as surrogate indicators of response to therapeutic intervention. Meanwhile, there is clear clinical need for greater accuracy in diagnosis and prognostic stratification. Fortunately, ongoing technological improvements and emerging data from randomized clinical trials are helping make these elusive goals a reality. This review provides an update on the current status of non-invasive coronary imaging with computed tomography, magnetic resonance, and positron emission tomography with a focus on current clinical applications and future research directions.

scholarly journals Physiological and Disease Models of Respiratory System Based on Organ-on-a-Chip Technology

Micromachines ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1106
Author(s):  
Di Wang ◽  
Ye Cong ◽  
Quanfeng Deng ◽  
Xiahe Han ◽  
Suonan Zhang ◽  
...  
Keyword(s):  
Respiratory Diseases ◽  
Solute Concentration ◽  
The Body ◽  
The Real ◽  
Growth State ◽  
Chip Technology ◽  
Organ On A Chip ◽  
And Function ◽  
Multiple Cells

The pathogenesis of respiratory diseases is complex, and its occurrence and development also involve a series of pathological processes. The present research methods are have difficulty simulating the natural developing state of the disease in the body, and the results cannot reflect the real growth state and function in vivo. The development of microfluidic chip technology provides a technical platform for better research on respiratory diseases. The size of its microchannel can be similar to the space for cell growth in vivo. In addition, organ-on-a-chip can achieve long-term co-cultivation of multiple cells and produce precisely controllable fluid shear force, periodically changing mechanical force, and perfusate with varying solute concentration gradient. To sum up, the chip can be used to analyze the specific pathophysiological changes of organs meticulously, and it is widely used in scientific research on respiratory diseases. The focus of this review is to describe and discuss current studies of artificial respiratory systems based on organ-on-a-chip technology and to summarize their applications in the real world.

scholarly journals Enhancing ultrasound texture differences for developing an in vivo 'virtual histology' approach to bovine ovarian imaging

2007 ◽  
Vol 19 (8) ◽  
pp. 910 ◽  
Author(s):  
Mark G. Eramian ◽  
Gregg P. Adams ◽  
Roger A. Pierson
Keyword(s):  
Image Processing ◽  
Ultrasound Image ◽  
Ultrasound Images ◽  
Virtual Histology ◽  
Form And Function ◽  
Non Invasive ◽  
Candidate Image ◽  
And Function ◽  
Processing Techniques

A ‘virtual histology’ can be thought of as the ‘staining’ of a digital ultrasound image via image processing techniques in order to enhance the visualisation of differences in the echotexture of different types of tissues. Several candidate image-processing algorithms for virtual histology using ultrasound images of the bovine ovary were studied. The candidate algorithms were evaluated qualitatively for the ability to enhance the visual differences in intra-ovarian structures and quantitatively, using standard texture description features, for the ability to increase statistical differences in the echotexture of different ovarian tissues. Certain algorithms were found to create textures that were representative of ovarian micro-anatomical structures that one would observe in actual histology. Quantitative analysis using standard texture description features showed that our algorithms increased the statistical differences in the echotexture of stroma regions and corpus luteum regions. This work represents a first step toward both a general algorithm for the virtual histology of ultrasound images and understanding dynamic changes in form and function of the ovary at the microscopic level in a safe, repeatable and non-invasive way.

In vivo and freeze-trapped assays of the energy state of brain and skeletal tissues

1980 ◽  
Vol 289 (1037) ◽  
pp. 457-457
Keyword(s):  
Energy State ◽  
Creatine Phosphate ◽  
Time Range ◽  
Damage Potential ◽  
Range Resolution ◽  
Non Invasive ◽  
Body Tissues ◽  
Positron Emission ◽  
Averaging Time

Non-invasive, non-destructive assay of energy-related metabolic activity of body tissues is the goal of several biophysical approaches, surface fluorometry of mitochondrial flavoprotein, positron emission tomography and 31 P n.m.r. Each has an appropriate specificity, time range, resolution and tissue damage potential. 31 P n.m.r. is the least invasive and at 72 MHz, with a 20 min averaging time and a 20 mm bore magnet, it affords in vivo assay of energy related compounds of tissues in small animals, such as fish skeletal muscle (loach) and heads of adult mouse and of newborn gerbils. In the transition from normoxia and nitrogen anoxia, decreases of the creatine phosphate : inorganic phosphate ratios from 3.9, 5.0, 2.7 in normoxia to 1.2, 0.04, 0.06 in anoxia occur in fish, mouse and gerbil respectively. The remarkable retention of significant ATP levels (80% of normoxic) in the new-born gerbil through 20 min of N 2 anoxia is clearly demonstrated. Evidence for the origin of much of the in vivo signal from the mouse brain is afforded by the fast freeze-trapping, excision of brain and assay by cryo-n.m.r. (Chance, B. et al . 1978 Proc. natn. Acad. Sci. U.S.A. 75, 4925-4929) at —12 °C, the lowest temperature at which tissue signals are observed.

scholarly journals The vasopressin mRNA poly(A) tract is unusually long and increases during stimulation of vasopressin gene expression in vivo.

1988 ◽  
Vol 8 (6) ◽  
pp. 2267-2274 ◽  
Author(s):  
E J Carrazana ◽  
K B Pasieka ◽  
J A Majzoub
Keyword(s):  
Gene Expression ◽  
Osmotic Stress ◽  
Genetic Regulation ◽  
Tail Length ◽  
Rnase H ◽  
The Body ◽  
Base Line ◽  
Tract Length ◽  
Stimulation Of

We developed a method, termed an H-blot, by which the poly(A) tract of any specific mRNA may be detected by RNA filter hybridization after its removal from the body of the mRNA by a RNase H-catalyzed endonucleolytic cleavage in the 3' untranslated region. Using this method, we studied the modulation of the length of the poly(A) tract of rat vasopressin mRNA in vivo during changes in the levels of this mRNA resulting from a physiologic stimulus, osmotic stress. The poly(A) tract of hypothalamic vasopressin mRNA in hydrated rats was, quite remarkably, approximately 250 nucleotides in length, in contrast to that of somatostatin mRNA, which was approximately 30 nucleotides long. Vasopressin mRNA poly(A) tail length increased progressively from approximately 250 to approximately 400 nucleotides with the application of the hyperosmotic stimulus and declined to base line after its removal; somatostatin mRNA poly(A) tail length did not change during osmotic stress. The poly(A) tract length of total hypothalamic mRNA was between 35 and 140 nucleotides and also did not change with osmotic stress. Modulation of poly(A) tract length of specific mRNAs during stimulation of gene expression may provide an additional level of genetic regulation.

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