Characterization of Atherosclerotic Plaque Depositions in vivo by Fiber-Optic Raman Spectroscopy and ex vivo by FTIR, Raman and Non-Linear Imaging Techniques

2012 ◽  
Vol 57 (SI-1 Track-E) ◽  
Author(s):  
C. Matthäus ◽  
R. Cicchi ◽  
S. Dochow ◽  
C. Krafft ◽  
A. Lattermann ◽  
...  
2019 ◽  
Vol 74 (1) ◽  
pp. 88-96
Author(s):  
Anders Runge Walther ◽  
Morten Østergaard Andersen ◽  
Christine Kamstrup Dam ◽  
Frederikke Karlsson ◽  
Martin Aage Barsøe Hedegaard

We investigated the ability to perform deep subsurface Raman spectroscopy in turbid media using a simple fiber optic volume probe. Being able to collect Raman signals from regions deep within a biological sample provides the ability to noninvasively study underlying living tissue and tissue engineered constructs with high chemical specificity. Spatially offset Raman spectroscopy has shown great potential for obtaining subsurface Raman signals in biological samples. The applicability of the method for in vivo studies depends on the system complexity and small size probes are often desirable. Most real-time studies on human patients utilizing Raman spectroscopy have been performed with easy-to-handle miniaturized probes. Here we show both experimentally and theoretically that the sampling depth from a simple volume probe can be controlled by changing the probe to sample distance effectively suppressing Raman and fluorescence contributions from shallow sample layers while favoring the collection of signals from deeper layers. Relative spectral intensities as function of probe to sample distance were investigated for layered phantoms of poly(methyl methacrylate) and trans-stilbene and compared with theory. The volume probe was then utilized for the collection of spectra from phantoms mimicking in vivo transcutaneous measurement configurations of bone and engineered scaffold as well as from an ex vivo sample of bone and soft tissue. Together the results show that Raman fiber optic volume probes can be utilized for subsurface Raman spectroscopy in turbid media, providing a simple alternative to spatially offset Raman systems for, e.g., noninvasive monitoring and studying mineralized tissue and implanted scaffolds in vivo.


The Analyst ◽  
2020 ◽  
Vol 145 (4) ◽  
pp. 1445-1456 ◽  
Author(s):  
Fabian Placzek ◽  
Eliana Cordero Bautista ◽  
Simon Kretschmer ◽  
Lara M. Wurster ◽  
Florian Knorr ◽  
...  

Characterization of bladder biopsies, using a combined fiber optic probe-based optical coherence tomography and Raman spectroscopy imaging system that allows a large field-of-view imaging and detection and grading of cancerous bladder lesions.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1791
Author(s):  
Rosa Scala ◽  
Fatima Maqoud ◽  
Nicola Zizzo ◽  
Giuseppe Passantino ◽  
Antonietta Mele ◽  
...  

(1) Background: Cantu syndrome (CS) arises from gain-of-function (GOF) mutations in the ABCC9 and KCNJ8 genes, which encode ATP-sensitive K+ (KATP) channel subunits SUR2 and Kir6.1, respectively. Most CS patients have mutations in SUR2, the major component of skeletal muscle KATP, but the consequences of SUR2 GOF in skeletal muscle are unknown. (2) Methods: We performed in vivo and ex vivo characterization of skeletal muscle in heterozygous SUR2[A478V] (SUR2wt/AV) and homozygous SUR2[A478V] (SUR2AV/AV) CS mice. (3) Results: In SUR2wt/AV and SUR2AV/AV mice, forelimb strength and diaphragm amplitude movement were reduced; muscle echodensity was enhanced. KATP channel currents recorded in Flexor digitorum brevis fibers showed reduced MgATP-sensitivity in SUR2wt/AV, dramatically so in SUR2AV/AV mice; IC50 for MgATP inhibition of KATP currents were 1.9 ± 0.5 × 10−5 M in SUR2wt/AV and 8.6 ± 0.4 × 10−6 M in WT mice and was not measurable in SUR2AV/AV. A slight rightward shift of sensitivity to inhibition by glibenclamide was detected in SUR2AV/AV mice. Histopathological and qPCR analysis revealed atrophy of soleus and tibialis anterior muscles and up-regulation of atrogin-1 and MuRF1 mRNA in CS mice. (4) Conclusions: SUR2[A478V] “knock-in” mutation in mice impairs KATP channel modulation by MgATP, markedly so in SUR2AV/AV, with atrophy and non-inflammatory edema in different skeletal muscle phenotypes.


Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 922
Author(s):  
William Querido ◽  
Shital Kandel ◽  
Nancy Pleshko

Advances in vibrational spectroscopy have propelled new insights into the molecular composition and structure of biological tissues. In this review, we discuss common modalities and techniques of vibrational spectroscopy, and present key examples to illustrate how they have been applied to enrich the assessment of connective tissues. In particular, we focus on applications of Fourier transform infrared (FTIR), near infrared (NIR) and Raman spectroscopy to assess cartilage and bone properties. We present strengths and limitations of each approach and discuss how the combination of spectrometers with microscopes (hyperspectral imaging) and fiber optic probes have greatly advanced their biomedical applications. We show how these modalities may be used to evaluate virtually any type of sample (ex vivo, in situ or in vivo) and how “spectral fingerprints” can be interpreted to quantify outcomes related to tissue composition and quality. We highlight the unparalleled advantage of vibrational spectroscopy as a label-free and often nondestructive approach to assess properties of the extracellular matrix (ECM) associated with normal, developing, aging, pathological and treated tissues. We believe this review will assist readers not only in better understanding applications of FTIR, NIR and Raman spectroscopy, but also in implementing these approaches for their own research projects.


Author(s):  
Massis Krekorian ◽  
Gerwin G. W. Sandker ◽  
Kimberley R. G. Cortenbach ◽  
Oya Tagit ◽  
N. Koen van Riessen ◽  
...  

2014 ◽  
Vol 136 (11) ◽  
Author(s):  
Wilfried Bürzle ◽  
Edoardo Mazza ◽  
John J. Moore

Puncture testing has been applied in several studies for the mechanical characterization of human fetal membrane (FM) tissue, and significant knowledge has been gained from these investigations. When comparing results of mechanical testing (puncture, inflation, and uniaxial tension), we have observed discrepancies in the rupture sequence of FM tissue and significant differences in the deformation behavior. This study was undertaken to clarify these discrepancies. Puncture experiments on FM samples were performed to reproduce previous findings, and numerical simulations were carried out to rationalize particular aspects of membrane failure. The results demonstrate that both rupture sequence and resistance to deformation depend on the samples' fixation. Soft fixation leads to slippage in the clamping, which reduces mechanical loading of the amnion layer and results in chorion rupturing first. Conversely, the stiffer, stronger, and less extensible amnion layer fails first if tight fixation is used. The results provide a novel insight into the interpretation of ex vivo testing as well as in vivo membrane rupture.


Theranostics ◽  
2017 ◽  
Vol 7 (14) ◽  
pp. 3517-3526 ◽  
Author(s):  
Kan Lin ◽  
Wei Zheng ◽  
Chwee Ming Lim ◽  
Zhiwei Huang

1999 ◽  
Vol 87 (3) ◽  
pp. 920-927 ◽  
Author(s):  
Kirby L. Zeman ◽  
Gerhard Scheuch ◽  
Knut Sommerer ◽  
James S. Brown ◽  
William D. Bennett

Effective airway dimensions (EADs) were determined in vivo by aerosol-derived airway morphometry as a function of volumetric lung depth (VLD) to identify and characterize, noninvasively, the caliber of the transitional bronchiole region of the human lung and to compare the EADs by age, gender, and disease. By logarithmically plotting EAD vs. VLD, two distinct regions of the lung emerged that were identified by characteristic line slopes. The intersection of proximal and distal segments was defined as VLDtransand associated EADtrans. In our normal subjects ( n = 20), VLDtrans [345 ± 83 (SD) ml] correlated significantly with anatomic dead space (224 ± 34 ml) and end of phase II of single-breath nitrogen washout (360 ± 53 ml). The corresponding EADtranswas 0.42 ± 0.07 mm, in agreement with other ex vivo measurements of the transitional bronchioles. VLDtrans was smaller (216 ± 64 ml) and EADtrans was larger (0.83 ± 0.04 mm) in our patients with chronic obstructive pulmonary disease ( n = 13). VLDtrans increased with age for children (age 8–18 yr; P = 0.006, n = 26) and with total lung capacity for age 8–81 yr ( P < 0.001, n = 61). This study extends the usefulness of aerosol-derived airway morphometry to in vivo measurements of the transitional bronchioles.


2005 ◽  
Vol 4 (4) ◽  
pp. 7290.2005.05133 ◽  
Author(s):  
Matthew J. Hardwick ◽  
Ming-Kai Chen ◽  
Kwamena Baidoo ◽  
Martin G. Pomper ◽  
Tomás R. Guilarte

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.


Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2874
Author(s):  
Hengfeng Yuan ◽  
Wen Jiang ◽  
Yuanxin Chen ◽  
Betty Kim

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.


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