scholarly journals An in vivo Probabilistic Atlas of the Human Locus Coeruleus at Ultra-high Field

2020 ◽  
Author(s):  
Rong Ye ◽  
Catarina Rua ◽  
Claire O’Callaghan ◽  
P Simon Jones ◽  
Frank Hezemans ◽  
...  
Keyword(s):  
Locus Coeruleus ◽  
Ex Vivo ◽  
Imaging Techniques ◽  
Magnetisation Transfer ◽  
Older Volunteers ◽  
Non Invasive ◽  
Probabilistic Atlas ◽  
Spatial Features ◽  
Magnetic Resonance Imaging Techniques

AbstractEarly and profound pathological changes are evident in the locus coeruleus (LC) in dementia and Parkinson’s disease, with effects on arousal, attention, cognitive and motor control. The LC can be identified in vivo using non-invasive magnetic resonance imaging techniques which have potential as biomarkers for detecting and monitoring disease progression. Technical limitations of existing imaging protocols have impaired the sensitivity to regional contrast variance or the spatial variability on the rostrocaudal extent of the LC, with spatial mapping consistent with post mortem findings. The current study employs a sensitive magnetisation transfer sequence using ultrahigh field 7T MRI to investigate the LC structure in vivo at high-resolution (resolution 0.4×0.4×0.5 mm, duration seven minutes). Magnetisation transfer images from 53 healthy older volunteers (52-84 years) revealed the spatial features of the LC and were used to create a probabilistic LC atlas for older adults, appropriate for clinical research. Consistent rostrocaudal gradients of slice-wise volume, contrast and variance differences of the LC were observed, mirroring distinctive ex vivo spatial distributions of LC cells in its subregions. The contrast-to-noise ratios were calculated for the peak voxels, and for the averaged signals within the atlas, to accommodate the volumetric differences in estimated contrast. The probabilistic atlas is freely available, and the MRI dataset is available for researchers, for replication or to facilitate accurate LC localisation and unbiased contrast extraction in future studies.

scholarly journals IMAGING TECHNIQUES FOR THE EVALUATION OF GRAPES IN WITHERING FOR AMARONE WINE PRODUCTION

2018 ◽  
Author(s):  
Barbara Cisterna ◽  
Federico Boschi ◽  
Anna Cleta Croce ◽  
Rachele Podda ◽  
Serena Zanzoni ◽  
...  
Keyword(s):  
Optical Properties ◽  
Ex Vivo ◽  
Imaging Techniques ◽  
Wine Production ◽  
Invasive Approach ◽  
Non Invasive ◽  
Innovative Materials ◽  
Amarone Wine

Optical Imaging (OI) is an emerging field developed in recent years which can be a very versatile, fast and non-invasive approach for the acquisition of images of  small (few centimetres) sized samples, such as layers of cells (in vitro), small animals (in vivo), animal organs (ex vivo) and innovative materials. OI was primarily developed for biomedical applications to study the progression of some pathologies and to assess the efficacy of new pharmaceutical compounds. Here we applied the OI technique to a completely new field: the study of food optical properties. In this case we exploited the optical properties of endogenous molecules, which are generally considered responsible of a background noise affecting the investigation. Here we used this sort of “noise”, named autofluorescence, to obtain information on the drying of Corvinone grapes employed for Amarone wine production. OI can provide interesting information and, inserted in a multimodal approach, it may be a real support to other techniques in the description of a biological phenomenon.

scholarly journals Non-invasive in vivo imaging of acute thrombosis: development of a novel factor XIIIa radiotracer

2019 ◽  
Vol 21 (6) ◽  
pp. 673-682 ◽  
Author(s):  
Jack P M Andrews ◽  
Christophe Portal ◽  
Tashfeen Walton ◽  
Mark G Macaskill ◽  
Patrick W F Hadoke ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Thrombus Formation ◽  
Imaging Techniques ◽  
Standard Uptake Value ◽  
Arterial Injury ◽  
Factor Xiiia ◽  
Acute Thrombosis ◽  
Non Invasive ◽  
Biodistribution Studies

Abstract Aims Cardiovascular thrombosis is responsible a quarter of deaths annually worldwide. Current imaging methods for cardiovascular thrombosis focus on anatomical identification of thrombus but cannot determine thrombus age or activity. Molecular imaging techniques hold promise for identification and quantification of thrombosis in vivo. Our objective was to assess a novel optical and positron-emitting probe targeting Factor XIIIa (ENC2015) as biomarker of active thrombus formation. Methods and results Optical and positron-emitting ENC2015 probes were assessed ex vivo using blood drawn from human volunteers and passed through perfusion chambers containing denuded porcine aorta as a model of arterial injury. Specificity of ENC2015 was established with co-infusion of a factor XIIIa inhibitor. In vivo18F-ENC2015 biodistribution, kinetics, radiometabolism, and thrombus binding were characterized in rats. Both Cy5 and fluorine-18 labelled ENC2015 rapidly and specifically bound to thrombi. Thrombus uptake was inhibited by a factor XIIIa inhibitor. 18F-ENC2015 remained unmetabolized over 8 h when incubated in ex vivo human blood. In vivo, 42% of parent radiotracer remained in blood 60 min post-administration. Biodistribution studies demonstrated rapid clearance from tissues with elimination via the urinary system. In vivo,18F-ENC2015 uptake was markedly increased in the thrombosed carotid artery compared to the contralateral patent artery (mean standard uptake value ratio of 2.40 vs. 0.74, P < 0.0001). Conclusion  ENC2015 rapidly and selectively binds to acute thrombus in both an ex vivo human translational model and an in vivo rodent model of arterial thrombosis. This probe holds promise for the non-invasive identification of thrombus formation in cardiovascular disease.

Normal variation in nephron numbers

2015 ◽  
Author(s):  
Michiel F. Schreuder
Keyword(s):  
Kidney Development ◽  
Ex Vivo ◽  
Imaging Techniques ◽  
Nutritional Deficiencies ◽  
Resonance Imaging ◽  
Intrauterine Growth ◽  
Nephron Endowment ◽  
Magnetic Resonance Imaging Techniques ◽  
Renal Size

Kidney development includes the formation of nephrons, which ceases around the 36th week of gestation. At that time, around 900,000 nephrons are formed, but with a 10-fold variation (from 200,000 to over 2 million). Many factors have been described to influence the number of nephrons per individual, such as genetic variations, intrauterine growth and prematurity, maternal diseases and (nutritional) deficiencies, and drugs used during nephrogenesis. Counting nephrons is currently only possible ex vivo, even though magnetic resonance imaging techniques are getting to the stage that in vivo estimations using stereology (the gold standard methodology) can be expected to become available in the next decade. In the meantime, renal size is often used as a marker for nephron endowment.

scholarly journals Radioimmunotheranostic Pair Based on the Anti-HER2 Monoclonal Antibody: Influence of Chelating Agents and Radionuclides on Biological Properties

Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 971
Author(s):  
Ana Cláudia Camargo Miranda ◽  
Sofia Nascimento dos Santos ◽  
Leonardo Lima Fuscaldi ◽  
Luiza Mascarenhas Balieiro ◽  
Maria Helena Bellini ◽  
...  
Keyword(s):  
Breast Cancer Cells ◽  
Chelating Agents ◽  
Ex Vivo ◽  
Imaging Techniques ◽  
Chelating Agent ◽  
Biological Properties ◽  
Non Invasive ◽  
The Stability ◽  
Ex Vivo Biodistribution

The oncogene HER2 is an important molecular target in oncology because it is associated with aggressive disease and the worst prognosis. The development of non-invasive imaging techniques and target therapies using monoclonal antibodies is a rapidly developing field. Thus, this work proposes the study of the radioimmunotheranostic pair, [111In]In-DTPA-trastuzumab and [177Lu]Lu-DOTA-trastuzumab, evaluating the influence of the chelating agents and radionuclides on the biological properties of the radioimmunoconjugates (RICs). The trastuzumab was immunoconjugated with the chelators DTPA and DOTA and radiolabeled with [111In]InCl3 and [177Lu]LuCl3, respectively. The stability of the RICs was evaluated in serum, and the immunoreactive and internalization fractions were determined in SK-BR-3 breast cancer cells. The in vivo pharmacokinetics and dosimetry quantification and the ex vivo biodistribution were performed in normal and SK-BR-3 tumor-bearing mice. The data showed that there was no influence of the chelating agents and radionuclides on the immunoreactive and internalization fractions of RICs. In contrast, they influenced the stability of RICs in serum, as well as the pharmacokinetics, dosimetry and biodistribution profiles. Therefore, the results showed that the nature of the chelating agent and radionuclide could influence the biological properties of the radioimmunotheranostic pair.

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.

scholarly journals In Vivo Imaging of Peripheral Benzodiazepine Receptors in Mouse Lungs: A Biomarker of Inflammation

2005 ◽  
Vol 4 (4) ◽  
pp. 7290.2005.05133 ◽  
Author(s):  
Matthew J. Hardwick ◽  
Ming-Kai Chen ◽  
Kwamena Baidoo ◽  
Martin G. Pomper ◽  
Tomás R. Guilarte
Keyword(s):  
In Vivo Imaging ◽  
Ex Vivo ◽  
Inflammatory Diseases ◽  
Imaging Techniques ◽  
Benzodiazepine Receptors ◽  
Small Animal ◽  
Small Animal Pet ◽  
Planar Imaging ◽  
Peripheral Benzodiazepine Receptors

The ability to visualize the immune response with radioligands targeted to immune cells will enhance our understanding of cellular responses in inflammatory diseases. Peripheral benzodiazepine receptors (PBR) are present in monocytes and neutrophils as well as in lung tissue. We used lipopolysaccharide (LPS) as a model of inflammation to assess whether the PBR could be used as a noninvasive marker of inflammation in the lungs. Planar imaging of mice administrated 10 or 30 mg/kg LPS showed increased [123I]-( R)-PK11195 radioactivity in the thorax 2 days after LPS treatment relative to control. Following imaging, lungs from control and LPS-treated mice were harvested for ex vivo gamma counting and showed significantly increased radioactivity above control levels. The specificity of the PBR response was determined using a blocking dose of nonradioactive PK11195 given 30 min prior to radiotracer injection. Static planar images of the thorax of nonradioactive PK11195 pretreated animals showed a significantly lower level of radiotracer accumulation in control and in LPS-treated animals ( p < .05). These data show that LPS induces specific increases in PBR ligand binding in the lungs. We also used in vivo small-animal PET studies to demonstrate increased [11C]-( R)-PK11195 accumulation in the lungs of LPS-treated mice. This study suggests that measuring PBR expression using in vivo imaging techniques may be a useful biomarker to image lung inflammation.

scholarly journals Study of Osteocyte Behavior by High-Resolution Intravital Imaging Following Photo-Induced Ischemia

Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2874
Author(s):  
Hengfeng Yuan ◽  
Wen Jiang ◽  
Yuanxin Chen ◽  
Betty Kim
Keyword(s):  
Imaging Techniques ◽  
Avascular Osteonecrosis ◽  
Functional Changes ◽  
Cellular Processes ◽  
Non Invasive ◽  
Behavioral Dynamics ◽  
Bony Anatomy ◽  
Magnetic Resonance Imaging Mri

Ischemic injuries and local hypoxia can result in osteocytes dysfunction and play a key role in the pathogenesis of avascular osteonecrosis. Conventional imaging techniques including magnetic resonance imaging (MRI) and computed tomography (CT) can reveal structural and functional changes within bony anatomy; however, characterization of osteocyte behavioral dynamics in the setting of osteonecrosis at the single cell resolution is limited. Here, we demonstrate an optical approach to study real-time osteocyte functions in vivo. Using nicotinamide adenine dinucleotide (NADH) as a biomarker for metabolic dynamics in osteocytes, we showed that NADH level within osteocytes transiently increase significantly after local ischemia through non-invasive photo-induced thrombosis of afferent arterioles followed by a steady decline. Our study presents a non-invasive optical approach to study osteocyte behavior through the modulation of local environmental conditions. Thus it provides a powerful toolkit to study cellular processes involved in bone pathologies in vivo.

scholarly journals EANM recommendations based on systematic analysis of small animal radionuclide imaging in inflammatory musculoskeletal diseases

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Erik H. J. G. Aarntzen ◽  
Edel Noriega-Álvarez ◽  
Vera Artiko ◽  
André H. Dias ◽  
Olivier Gheysens ◽  
...  
Keyword(s):  
Molecular Imaging ◽  
Radionuclide Imaging ◽  
Musculoskeletal Diseases ◽  
Ex Vivo ◽  
Imaging Techniques ◽  
Large Body ◽  
Therapeutic Interventions ◽  
Histopathological Analysis ◽  
Complementary Value

AbstractInflammatory musculoskeletal diseases represent a group of chronic and disabling conditions that evolve from a complex interplay between genetic and environmental factors that cause perturbations in innate and adaptive immune responses. Understanding the pathogenesis of inflammatory musculoskeletal diseases is, to a large extent, derived from preclinical and basic research experiments. In vivo molecular imaging enables us to study molecular targets and to measure biochemical processes non-invasively and longitudinally, providing information on disease processes and potential therapeutic strategies, e.g. efficacy of novel therapeutic interventions, which is of complementary value next to ex vivo (post mortem) histopathological analysis and molecular assays. Remarkably, the large body of preclinical imaging studies in inflammatory musculoskeletal disease is in contrast with the limited reports on molecular imaging in clinical practice and clinical guidelines. Therefore, in this EANM-endorsed position paper, we performed a systematic review of the preclinical studies in inflammatory musculoskeletal diseases that involve radionuclide imaging, with a detailed description of the animal models used. From these reflections, we provide recommendations on what future studies in this field should encompass to facilitate a greater impact of radionuclide imaging techniques on the translation to clinical settings.

scholarly journals Towards Clinical Translation of LED-Based Photoacoustic Imaging: A Review

Sensors ◽  
2020 ◽  
Vol 20 (9) ◽  
pp. 2484 ◽  
Author(s):  
Yunhao Zhu ◽  
Ting Feng ◽  
Qian Cheng ◽  
Xueding Wang ◽  
Sidan Du ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Photoacoustic Imaging ◽  
Imaging Techniques ◽  
Clinical Translation ◽  
Key Factors ◽  
Pilot Studies ◽  
History Of ◽  
Molecular Components ◽  
Clinical Potential

Photoacoustic imaging, with the capability to provide simultaneous structural, functional, and molecular information, is one of the fastest growing biomedical imaging modalities of recent times. As a hybrid modality, it not only provides greater penetration depth than the purely optical imaging techniques, but also provides optical contrast of molecular components in the living tissue. Conventionally, photoacoustic imaging systems utilize bulky and expensive class IV lasers, which is one of the key factors hindering the clinical translation of this promising modality. Use of LEDs which are portable and affordable offers a unique opportunity to accelerate the clinical translation of photoacoustics. In this paper, we first review the development history of LED as an illumination source in biomedical photoacoustic imaging. Key developments in this area, from point-source measurements to development of high-power LED arrays, are briefly discussed. Finally, we thoroughly review multiple phantom, ex-vivo, animal in-vivo, human in-vivo, and clinical pilot studies and demonstrate the unprecedented preclinical and clinical potential of LED-based photoacoustic imaging.

Sign in / Sign up

Export Citation Format

Share Document