scholarly journals Multi-Spectral Clinical Prototype for Fluorophore Detection

2021 ◽  
Vol 9 ◽  
Author(s):  
Konstantin Grygoryev ◽  
Huihui Lu ◽  
Celina L. Li ◽  
Alexander V. Zhdanov ◽  
Ray Burke ◽  
...  

Identification of tumour margins during resection of the brain is critical for improving the post-operative outcomes. Current methods of tumour identification use 5-ALA, an exogenous precursor, metabolized to fluorescent PpIX in tumour tissue. Although visible under fluorescent microscope, PpIX is easily photo-bleached and tumour tagging is subjective, resulting in tumour under-resection and accelerated recurrence. To address this issue, photo-bleaching resistant and quantitative method is required. This study describes the characterization of a pulsed, multi-wavelengths system designed to measure diffuse reflectance and auto-fluorescence under strong ambient illumination conditions. The performance was tested on n = 400 liquid tissue phantoms containing a wide concentration range of absorber, scatterer and two fluorophores as well as on ex-vivo samples of gray and white matter. The background subtraction technique was shown to be efficient for a range of ambient illumination intensities. A linear relationship was observed between system response and predicted fluorophore concentrations as well as 97.8% accuracy of tissue classification by 5-fold cross-correlation, linear SVM.

Author(s):  
Amal Alzain ◽  
Suhaib Alameen ◽  
Rani Elmaki ◽  
Mohamed E. M. Gar-Elnabi

This study concern to characterize the brain tissues to ischemic stroke, gray matter, white matter and CSF using texture analysisto extract classification features from CT images. The First Order Statistic techniques included sevenfeatures. To find the gray level variation in CT images it complements the FOS features extracted from CT images withgray level in pixels and estimate the variation of thesubpatterns. analyzing the image with Interactive Data Language IDL software to measure the grey level of images. The results show that the Gray Level variation and   features give classification accuracy of ischemic stroke 97.6%, gray matter95.2%, white matter 97.3% and the CSF classification accuracy 98.0%. The overall classification accuracy of brain tissues 97.0%.These relationships are stored in a Texture Dictionary that can be later used to automatically annotate new CT images with the appropriate brain tissues names.


1997 ◽  
Vol 35 (2-3) ◽  
pp. 85-91
Author(s):  
D. A. Barton ◽  
J. D. Woodruff ◽  
T. M. Bousquet ◽  
A. M. Parrish

If promulgated as proposed, effluent guidelines for the U.S. pulp and paper industry will impose average monthly and maximum daily numerical limits of discharged AOX (adsorbable organic halogen). At this time, it is unclear whether the maximum-day variability factor used to establish the proposed effluent guidelines will provide sufficient margin for mills to achieve compliance during periods of normal but variable operating conditions within the pulping and bleaching processes. Consequently, additional information is needed to relate transient AOX loadings with final AOX discharges. This paper presents a simplistic dynamic model of AOX decay during treatment. The model consists of hydraulic characterization of an activated sludge process and a first-order decay coefficient for AOX removal. Data for model development were acquired by frequent collection of influent and effluent samples at a bleach kraft mill during a bleach plant shutdown and startup sequence.


Author(s):  
Stefano Vassanelli

Establishing direct communication with the brain through physical interfaces is a fundamental strategy to investigate brain function. Starting with the patch-clamp technique in the seventies, neuroscience has moved from detailed characterization of ionic channels to the analysis of single neurons and, more recently, microcircuits in brain neuronal networks. Development of new biohybrid probes with electrodes for recording and stimulating neurons in the living animal is a natural consequence of this trend. The recent introduction of optogenetic stimulation and advanced high-resolution large-scale electrical recording approaches demonstrates this need. Brain implants for real-time neurophysiology are also opening new avenues for neuroprosthetics to restore brain function after injury or in neurological disorders. This chapter provides an overview on existing and emergent neurophysiology technologies with particular focus on those intended to interface neuronal microcircuits in vivo. Chemical, electrical, and optogenetic-based interfaces are presented, with an analysis of advantages and disadvantages of the different technical approaches.


2019 ◽  
Vol 45 (4) ◽  
pp. 1092-1099
Author(s):  
Roberto Cannella ◽  
Mohammed Shahait ◽  
Alessandro Furlan ◽  
Feng Zhang ◽  
Joel D. Bigley ◽  
...  

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.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Takahiro Morito ◽  
Ryuichi Harada ◽  
Ren Iwata ◽  
Yiqing Du ◽  
Nobuyuki Okamura ◽  
...  

AbstractBrain positron emission tomography (PET) imaging with radiolabelled proteins is an emerging concept that potentially enables visualization of unique molecular targets in the brain. However, the pharmacokinetics and protein radiolabelling methods remain challenging. Here, we report the performance of an engineered, blood–brain barrier (BBB)-permeable affibody molecule that exhibits rapid clearance from the brain, which was radiolabelled using a unique fluorine-18 labelling method, a cell-free protein radiosynthesis (CFPRS) system. AS69, a small (14 kDa) dimeric affibody molecule that binds to the monomeric and oligomeric states of α-synuclein, was newly designed for brain delivery with an apolipoprotein E (ApoE)-derived brain shuttle peptide as AS69-ApoE (22 kDa). The radiolabelled products 18F-AS69 and 18F-AS69-ApoE were successfully synthesised using the CFPRS system. Notably, 18F-AS69-ApoE showed higher BBB permeability than 18F-AS69 in an ex vivo study at 10 and 30 min post injection and was partially cleared from the brain at 120 min post injection. These results suggest that small, a brain shuttle peptide-fused fluorine-18 labelled protein binders can potentially be utilised for brain molecular imaging.


Sign in / Sign up

Export Citation Format

Share Document