scholarly journals Contrast Enhancement for in Vivo Visible Reflectance Imaging of Tissue Oxygenation

2007 ◽  
Vol 61 (8) ◽  
pp. 797-803 ◽  
Author(s):  
Nicole J. Crane ◽  
Zachary D. Schultz ◽  
Ira W. Levin

Results are presented illustrating a straightforward algorithm to be used for real-time monitoring of oxygenation levels in blood cells and tissue based on the visible spectrum of hemoglobin. Absorbance images obtained from the visible reflection of white light through separate red and blue bandpass filters recorded by monochrome charge-coupled devices (CCDs) are combined to create enhanced images that suggest a quantitative correlation between the degree of oxygenated and deoxygenated hemoglobin in red blood cells. The filter bandpass regions are chosen specifically to mimic the color response of commercial 3-CCD cameras, representative of detectors with which the operating room laparoscopic tower systems are equipped. Adaptation of this filter approach is demonstrated for laparoscopic donor nephrectomies in which images are analyzed in terms of real-time in vivo monitoring of tissue oxygenation.

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Chengzhong Cai ◽  
Dmitry A. Nedosekin ◽  
Yulian A. Menyaev ◽  
Mustafa Sarimollaoglu ◽  
Mikhail A. Proskurnin ◽  
...  

Control of sickle cell disease (SCD) stage and treatment efficiency are still time-consuming which makes well-timed prevention of SCD crisis difficult. We show here thatin vivophotoacoustic (PA) flow cytometry (PAFC) has a potential for real-time monitoring of circulating sickled cells in mouse model.In vivodata were verified byin vitroPAFC and photothermal (PT) and PA spectral imaging of sickle red blood cells (sRBCs) expressing SCD-associated hemoglobin (HbS) compared to normal red blood cells (nRBCs). We discovered that PT and PA signal amplitudes from sRBCs in linear mode were 2–4-fold lower than those from nRBCs. PT and PA imaging revealed more profound spatial hemoglobin heterogeneity in sRBCs than in nRBCs, which can be associated with the presence of HbS clusters with high local absorption. This hypothesis was confirmed in nonlinear mode through nanobubble formation around overheated HbS clusters accompanied by spatially selective signal amplification. More profound differences in absorption of sRBCs than in nRBCs led to notable increase in PA signal fluctuation (fluctuation PAFC mode) as an indicator of SCD. The obtained data suggest that noninvasive label-free fluctuation PAFC has a potential for real-time enumeration of sRBCs bothin vitroandin vivo.


Author(s):  
D.J.P. Ferguson ◽  
A.R. Berendt ◽  
J. Tansey ◽  
K. Marsh ◽  
C.I. Newbold

In human malaria, the most serious clinical manifestation is cerebral malaria (CM) due to infection with Plasmodium falciparum. The pathology of CM is thought to relate to the fact that red blood cells containing mature forms of the parasite (PRBC) cytoadhere or sequester to post capillary venules of various tissues including the brain. This in vivo phenomenon has been studied in vitro by examining the cytoadherence of PRBCs to various cell types and purified proteins. To date, three Ijiost receptor molecules have been identified; CD36, ICAM-1 and thrombospondin. The specific changes in the PRBC membrane which mediate cytoadherence are less well understood, but they include the sub-membranous deposition of electron-dense material resulting in surface deformations called knobs. Knobs were thought to be essential for cytoadherence, lput recent work has shown that certain knob-negative (K-) lines can cytoadhere. In the present study, we have used electron microscopy to re-examine the interactions between K+ PRBCs and both C32 amelanotic melanoma cells and human umbilical vein endothelial cells (HUVEC).We confirm previous data demonstrating that C32 cells possess numerous microvilli which adhere to the PRBC, mainly via the knobs (Fig. 1). In contrast, the HUVEC were relatively smooth and the PRBCs appeared partially flattened onto the cell surface (Fig. 2). Furthermore, many of the PRBCs exhibited an invagination of the limiting membrane in the attachment zone, often containing a cytoplasmic process from the endothelial cell (Fig. 2).


1965 ◽  
Vol 13 (01) ◽  
pp. 065-083 ◽  
Author(s):  
Shirley A. Johnson ◽  
Ronaldo S. Balboa ◽  
Harlan J. Pederson ◽  
Monica Buckley

SummaryThe ultrastructure of platelet aggregation in vivo in response to bleeding brought about by transection of small mesenteric vessels in rats and guinea pigs has been studied. Platelets aggregate, degranulate and separating membranes disappear in parallel with fibrin appearance which is first seen at several loci after 30 seconds of bleeding. About 40 per cent of the electron opaque granules, some of which contain platelet factor 3 have disappeared after one minute of bleeding while the electron lucent granules increase by 70 per cent suggesting that some of them may be empty vesicles. Most of the platelet aggregates of the random type disappear leaving clumped red blood cells entrapped by a network of fibrin fibers which emanate from the remains of platelet aggregates of the rosette type to maintain hemostasis.


2020 ◽  
Vol 17 ◽  
Author(s):  
Tarek Faris ◽  
Gamaleldin I. Harisa ◽  
Fars K. Alanazi ◽  
Mohamed M. Badran ◽  
Afraa Mohammad Alotaibi ◽  
...  

Aim: This study aimed to explore an affordable technique for the fabrication of Chitosan Nanoshuttles (CSNS) at the ultrafine nanoscale less than 100 nm with improved physicochemical properties, and cytotoxicity on the MCF-7 cell line. Background: Despite several studies reported that the antitumor effect of CS and CSNS could achieve intracellular compartment target ability, no enough available about this issue and further studies are required to address this assumption. Objectives: The objective of the current study was to investigate the potential processing variables for the production of ultrafine CSNS (> 100 nm) using Box-Benhken Design factorial design (BBD). This was achieved through a study of the effects of processing factors, such as CS concentration, CS/TPP ratio, and pH of the CS solution, on PS, PDI, and ZP. Moreover, the obtained CSNS was evaluated for physicochemical characteristics, morphology Also, hemocompatibility, and cytotoxicity using Red Blood Cells (RBCs) and MCF-7 cell lines were investigated. Methods: Box-Benhken Design factorial design (BBD) was used in the analysis of different selected variables. The effects of CS concentration, sodium tripolyphosphate (TPP) ratio, and pH on particle size, Polydispersity Index (PDI), and Zeta Potential (ZP) were measured. Subsequently, the prepared CS nanoshuttles were exposed to stability studies, physicochemical characterization, hemocompatibility, and cytotoxicity using red blood cells and MCF-7 cell lines as surrogate models for in vivo study. Result: The present results revealed that the optimized CSNS have ultrafine nanosize, (78.3±0.22 nm), homogenous with PDI (0.131±0.11), and ZP (31.9±0.25 mV). Moreover, CSNS have a spherical shape, amorphous in structure, and physically stable. Also, CSNS has biological safety as indicated by a gentle effect on red blood cell hemolysis, besides, the obtained nanoshuttles decrease MCF-7 viability. Conclusion: The present findings concluded that the developed ultrafine CSNS has unique properties with enhanced cytotoxicity. thus promising for use in intracellular organelles drug delivery.


2019 ◽  
Vol 15 (5) ◽  
pp. 567-574
Author(s):  
Huck Jun Hong ◽  
Suw Young Ly

Background: Tetrodotoxin (TTX) is a biosynthesized neurotoxin that exhibits powerful anticancer and analgesic abilities by inhibiting voltage-gated sodium channels that are crucial for cancer metastasis and pain delivery. However, for the toxin’s future medical applications to come true, accurate, inexpensive, and real-time in vivo detection of TTX remains as a fundamental step. Methods: In this study, highly purified TTX extracted from organs of Takifugu rubripes was injected and detected in vivo of mouse organs (liver, heart, and intestines) using Cyclic Voltammetry (CV) and Square Wave Anodic Stripping Voltammetry (SWASV) for the first time. In vivo detection of TTX was performed with auxiliary, reference, and working herring sperm DNA-immobilized carbon nanotube sensor systems. Results: DNA-immobilization and optimization of amplitude (V), stripping time (sec), increment (mV), and frequency (Hz) parameters for utilized sensors amplified detected peak currents, while highly sensitive in vivo detection limits, 3.43 µg L-1 for CV and 1.21 µg L-1 for SWASV, were attained. Developed sensors herein were confirmed to be more sensitive and selective than conventional graphite rodelectrodes modified likewise. A linear relationship was observed between injected TTX concentration and anodic spike peak height. Microscopic examination displayed coagulation and abnormalities in mouse organs, confirming the powerful neurotoxicity of extracted TTX. Conclusion: These results established the diagnostic measures for TTX detection regarding in vivo application of neurotoxin-deviated anticancer agents and analgesics, as well as TTX from food poisoning and environmental contamination.


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