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Design of a Closed Loop System for Glaucoma Treatment including Measurement of Intraocular Pressure and Therapeutic Stimulation of the EyeRachael Swenson (6615704) 11 June 2019 (has links)
<p>Glaucoma is the leading cause
of irreversible blindness worldwide effecting more than 2.7 million people in
the U.S alone. Treatments exist in the form of both pharmaceutical and surgical
options, but often do not provide the desired efficacy. For example, the
failure rate of a trabeculectomy procedure is 39% within 5 years. Additionally,
none of the current glaucoma treatments allow for closed loop monitoring of
pressure, therefore requiring more frequent doctor visits. Glaucoma management can
be improved through the use of a closed loop application of electroceutical
treatment. The goal is to develop an implantable device that will be inserted
into the eye to monitor intraocular pressure (IOP) and provide responsive therapeutic
stimulation to the eye. I designed a discrete pressure monitoring system that
interacts with a bare die piezoresistive pressure sensor. The system is based
on a Wheatstone bridge design which translates the input resistances of the
pressure sensor into a voltage output. This system has an average accuracy of
0.53 mmHg and draws 295 µW
of power. I then combined this pressure system with data processing code and
Howland current pump stimulation circuitry. This simulation system can output
up to 1.05 mA of current for electroceutical intraocular stimulation to lower
IOP. Future work will involve miniaturizing the circuitries in the form of an
ASIC and packaging the entire system into an ocular implant. This implant can
wirelessly monitor IOP and provide therapeutic stimulation to lower IOP. A
reliable, closed loop method of lowering IOP would greatly benefit the ever-growing
population affected by glaucoma.</p>
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Arquitetura de hardware para monitor de UTI segundo padrão IEEE 1451: uma prova de conceitoPereira, Mário Wilson Paiva 28 July 2017 (has links)
PEREIRA, Mário Wilson Paiva. Arquitetura de hardware para monitor de UTI segundo padrão IEEE 1451: uma prova de conceito. 2017. 125 f. Dissertação (Mestrado em Engenharia de Teleinformática)–Centro de Tecnologia, Universidade Federal do Ceará, Fortaleza, 2017. / Submitted by Renato Vasconcelos (ppgeti@ufc.br) on 2017-11-17T18:30:25Z
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10 Na lista de referencias, retire a informação, que está no final de cada obra citada, do numero de vezes que o autor foi citado em seu trabalho.
Quando citar documentos consultados online, colocar autor. título. disponível em: <endereço eletrônico> Acesso em: data (dia, mes e ano). Corrigir em toda a lista.
on 2017-11-20T13:21:38Z (GMT) / Submitted by Renato Vasconcelos (ppgeti@ufc.br) on 2017-11-29T12:30:37Z
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ANAHP. Observatório 2015.
GARCIA, W. L. C. Teds-easy - descricão automática de transducer electronic data sheet
MARCONDES, A. Desenvolvimento de protótipo de gravador de TEDS e de etiqueta eletrônica TEDS
PRIYA, M. et al. Embedded based wireless ICU monitoring system
ROSSI, S. R.; RODRIGUES DA SILVA, A. C.; SANTOS FILHO, T. A. D. IEEE 1451.2- based sensor system with JAVA-TEDS software Tool
TESTER, S. N. C. et al. An IEEE 1451 TEDS compiler and serial network compliance tester.
Att.
Marlene
3366-9620
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Previous issue date: 2017-07-28 / This work presents the development of a hardware architecture for ICU monitors, combining
design stages of embedded systems, biomedical instrumentation, intelligent sensors and
the IEEE 1451 protocol. The method used defines operational requirements, system
decomposition into modules, architecture definition and implementation using commercial
development platforms. The entire process is based on national and international standards
and protocols, seeking to design the system within the constraints of a product and validate
the concept through printed circuit board prototypes. The proposed architecture establishes
a network of intelligent biomedical sensors, called STIM, controlled by a central node, called
NCAP. The use of this architecture provides modular, self-configuring, easy-to-maintain,
plug and play sensors with standardized communication and data interface. The work also
describes the process of creating electronic data sheets of the STIMs, called TEDS, which
contain the operation characteristics of each smart sensor. / Este trabalho apresenta o desenvolvimento de uma arquitetura de hardware para moni-
tores de UTI combinando etapas do projeto de sistemas embarcados, instrumentação
biomédica, sensores inteligentes e o protocolo IEEE 1451. A metodologia empregada
define requisitos operacionais, decomposição do sistema em módulos, definição da
arquitetura e implementação utilizando plataformas de desenvolvimento comerciais.
Todo o processo é baseado em normas e protocolos de órgãos nacionais e internacionais
procurando projetar o sistema dentro das restrições de um produto e validar o conceito
por meio de protótipos em placas de circuito impresso. A arquitetura proposta estabelece
uma rede de sensores biomédicos inteligentes, denominados STIM, controlados por
um elemento cental, denominado NCAP. A utilização desta arquitetura proporciona
sensores modulares, autoconfiguráveis, de fácil manutenção, plug and play, com interface
de comunicação e dados padronizados. O trabalho também descreve o processo de
criação de folhas de dados eletrônicas dos STIMs, denominadas TEDS, que contêm as
características de operação de cada sensor inteligente.
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Aquisição, processamento de sinais mioelétricos e máquina de vetores de suporte para caracterização de movimentos do segmento mão-braçoNilson, Clairê de Pauli January 2014 (has links)
As diversas áreas da Engenharia, em parceria com a ciência médica, têm contribuído de forma eficaz para o avanço do conhecimento e dos resultados em aplicações práticas na vida do deficiente físico. De forma geral, pesquisas com este foco têm permitido o desenvolvimento de dispositivos e recursos com o objetivo de oferecer novamente a mobilidade e a liberdade perdidas com a deficiência. Este trabalho tem a finalidade de desenvolver um sistema que utiliza Eletromiografia de Superfície e Máquina de Vetores de Suporte para a caracterização de determinados movimentos de um braço humano, possibilitando, futuramente, a integração em sistemas de reabilitação. Primeiramente os sinais mioelétricos são obtidos nos músculos do braço de voluntários através de eletrodos de superfície ligados a um eletromiógrafo. O sinal é adquirido, utilizando como padrão um modelo virtual que demonstra ao voluntário os movimentos do segmento mão-braço que devem ser imitados. Esses movimentos são executados e seus sinais mioelétricos adquiridos. Posteriormente, esses sinais são processados e características são extraídas. Em seguida, são alocadas algumas de suas características (RMS, média, variância, desvio padrão, skewness e kurtosis) na entrada da Máquina de Vetores de Suporte, que apresenta, como saída, o reconhecimento, ou não, do movimento previamente executado pelo voluntário. No final do processo, observou-se que aumentando o número de canais elevou-se a taxa de acerto dos movimentos e, com a retirada de determinada característica, houve decréscimo na taxa de acerto do sistema. Nestes casos, os 9 movimentos distintos atingiram uma taxa de acerto média de 83,2%, para dois canais, e 91,3%, para oito canais, e, em ambos sistemas de canais, com as seis características. / A wide range of engineering scopes, along with the knowledge from the medical science, has efficiently been contributing to further knowledge and results for practical applications in the life of the physically challenged. In general, such researches have allowed the development of devices and resources aimed at giving back the mobility and freedom lost with the deficiency. This paper intends to develop a system that uses Surface Electromyography and Support-Vector Machines (SVM) for the characterization of specific movements of a human arm enabling the future integration in rehabilitation systems. At first, myoelectric signals are obtained in the arm muscles of volunteers by means of surface electrodes attached to an Electromyography. The signal is acquired using a virtual model as pattern demonstrating to the volunteer the hand-arm movements which are to be replicated by the subject. As these movements are done, its respective myoelectric signals are acquired. Later on, these signals are processed and their characteristics extracted. Some of these features (such as RMS, standard deviation, variance, mean, kurtosis, skewness) will then be inserted in as input data in the Support- Vector Machine, which shows as an output a valid or null recognition of the movement earlier executed by the volunteer. At the end of the process, it was observed that increasing the number of channels increased by hit rate movements and, with the removal of certain characteristic, there was a decrease in the hit rate of the system. In these cases, nine distinct movements reached an average accuracy of 83.2% for two channels, and 91.3% for eight channels, and in both systems of channels, with six features.
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Aquisição, processamento de sinais mioelétricos e máquina de vetores de suporte para caracterização de movimentos do segmento mão-braçoNilson, Clairê de Pauli January 2014 (has links)
As diversas áreas da Engenharia, em parceria com a ciência médica, têm contribuído de forma eficaz para o avanço do conhecimento e dos resultados em aplicações práticas na vida do deficiente físico. De forma geral, pesquisas com este foco têm permitido o desenvolvimento de dispositivos e recursos com o objetivo de oferecer novamente a mobilidade e a liberdade perdidas com a deficiência. Este trabalho tem a finalidade de desenvolver um sistema que utiliza Eletromiografia de Superfície e Máquina de Vetores de Suporte para a caracterização de determinados movimentos de um braço humano, possibilitando, futuramente, a integração em sistemas de reabilitação. Primeiramente os sinais mioelétricos são obtidos nos músculos do braço de voluntários através de eletrodos de superfície ligados a um eletromiógrafo. O sinal é adquirido, utilizando como padrão um modelo virtual que demonstra ao voluntário os movimentos do segmento mão-braço que devem ser imitados. Esses movimentos são executados e seus sinais mioelétricos adquiridos. Posteriormente, esses sinais são processados e características são extraídas. Em seguida, são alocadas algumas de suas características (RMS, média, variância, desvio padrão, skewness e kurtosis) na entrada da Máquina de Vetores de Suporte, que apresenta, como saída, o reconhecimento, ou não, do movimento previamente executado pelo voluntário. No final do processo, observou-se que aumentando o número de canais elevou-se a taxa de acerto dos movimentos e, com a retirada de determinada característica, houve decréscimo na taxa de acerto do sistema. Nestes casos, os 9 movimentos distintos atingiram uma taxa de acerto média de 83,2%, para dois canais, e 91,3%, para oito canais, e, em ambos sistemas de canais, com as seis características. / A wide range of engineering scopes, along with the knowledge from the medical science, has efficiently been contributing to further knowledge and results for practical applications in the life of the physically challenged. In general, such researches have allowed the development of devices and resources aimed at giving back the mobility and freedom lost with the deficiency. This paper intends to develop a system that uses Surface Electromyography and Support-Vector Machines (SVM) for the characterization of specific movements of a human arm enabling the future integration in rehabilitation systems. At first, myoelectric signals are obtained in the arm muscles of volunteers by means of surface electrodes attached to an Electromyography. The signal is acquired using a virtual model as pattern demonstrating to the volunteer the hand-arm movements which are to be replicated by the subject. As these movements are done, its respective myoelectric signals are acquired. Later on, these signals are processed and their characteristics extracted. Some of these features (such as RMS, standard deviation, variance, mean, kurtosis, skewness) will then be inserted in as input data in the Support- Vector Machine, which shows as an output a valid or null recognition of the movement earlier executed by the volunteer. At the end of the process, it was observed that increasing the number of channels increased by hit rate movements and, with the removal of certain characteristic, there was a decrease in the hit rate of the system. In these cases, nine distinct movements reached an average accuracy of 83.2% for two channels, and 91.3% for eight channels, and in both systems of channels, with six features.
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Aquisição, processamento de sinais mioelétricos e máquina de vetores de suporte para caracterização de movimentos do segmento mão-braçoNilson, Clairê de Pauli January 2014 (has links)
As diversas áreas da Engenharia, em parceria com a ciência médica, têm contribuído de forma eficaz para o avanço do conhecimento e dos resultados em aplicações práticas na vida do deficiente físico. De forma geral, pesquisas com este foco têm permitido o desenvolvimento de dispositivos e recursos com o objetivo de oferecer novamente a mobilidade e a liberdade perdidas com a deficiência. Este trabalho tem a finalidade de desenvolver um sistema que utiliza Eletromiografia de Superfície e Máquina de Vetores de Suporte para a caracterização de determinados movimentos de um braço humano, possibilitando, futuramente, a integração em sistemas de reabilitação. Primeiramente os sinais mioelétricos são obtidos nos músculos do braço de voluntários através de eletrodos de superfície ligados a um eletromiógrafo. O sinal é adquirido, utilizando como padrão um modelo virtual que demonstra ao voluntário os movimentos do segmento mão-braço que devem ser imitados. Esses movimentos são executados e seus sinais mioelétricos adquiridos. Posteriormente, esses sinais são processados e características são extraídas. Em seguida, são alocadas algumas de suas características (RMS, média, variância, desvio padrão, skewness e kurtosis) na entrada da Máquina de Vetores de Suporte, que apresenta, como saída, o reconhecimento, ou não, do movimento previamente executado pelo voluntário. No final do processo, observou-se que aumentando o número de canais elevou-se a taxa de acerto dos movimentos e, com a retirada de determinada característica, houve decréscimo na taxa de acerto do sistema. Nestes casos, os 9 movimentos distintos atingiram uma taxa de acerto média de 83,2%, para dois canais, e 91,3%, para oito canais, e, em ambos sistemas de canais, com as seis características. / A wide range of engineering scopes, along with the knowledge from the medical science, has efficiently been contributing to further knowledge and results for practical applications in the life of the physically challenged. In general, such researches have allowed the development of devices and resources aimed at giving back the mobility and freedom lost with the deficiency. This paper intends to develop a system that uses Surface Electromyography and Support-Vector Machines (SVM) for the characterization of specific movements of a human arm enabling the future integration in rehabilitation systems. At first, myoelectric signals are obtained in the arm muscles of volunteers by means of surface electrodes attached to an Electromyography. The signal is acquired using a virtual model as pattern demonstrating to the volunteer the hand-arm movements which are to be replicated by the subject. As these movements are done, its respective myoelectric signals are acquired. Later on, these signals are processed and their characteristics extracted. Some of these features (such as RMS, standard deviation, variance, mean, kurtosis, skewness) will then be inserted in as input data in the Support- Vector Machine, which shows as an output a valid or null recognition of the movement earlier executed by the volunteer. At the end of the process, it was observed that increasing the number of channels increased by hit rate movements and, with the removal of certain characteristic, there was a decrease in the hit rate of the system. In these cases, nine distinct movements reached an average accuracy of 83.2% for two channels, and 91.3% for eight channels, and in both systems of channels, with six features.
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Automation of the Supine Pressor Test for PreeclampsiaHamna Qureshi (6611528) 15 May 2019 (has links)
<p><a>Preeclampsia leads to increased risk of
morbidity and mortality for both mother and fetus. Most previous studies have
largely neglected mechanical compression of the left renal vein by the gravid
uterus as a potential mechanism. In this study we first used a murine model to
investigate the pathophysiology of left renal vein constriction. The results
indicate that prolonged renal vein stenosis after 14 days can cause renal
necrosis and an increase in blood pressure (BP) of roughly 30 mmHg. The second
part of this study aimed to automate a diagnostic tool, known as the supine
pressor test (SPT), to enable pregnant women to assess their preeclampsia development
risk. A positive SPT has been previously defined as an increase of at least 20
mmHg in diastolic BP when switching between left lateral recumbent and supine
positions. The results from this study established a baseline BP increase
between the two body positions in non-pregnant female subjects and demonstrated
the feasibility and utility of an automated SPT in pregnant women. Our results
demonstrate that there is a baseline increase in BP of roughly 10-14 mmHg and
that pregnant women can autonomously perform the SPT. Overall, this work in
both rodents and humans suggests that 1) stenosis of the left renal vein in
mice leads to elevation in BP and acute renal failure, 2) non-pregnant women
experience a baseline increase in BP when they shift from left lateral recumbent
to supine position, and 3) the SPT can be automated and used autonomously.</a></p>
<br>
<p> </p>
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Analysis of Heart Rate Variability During Focal Parasympathetic Drive of the Rat BaroreflexDavid Jacob Bustamante (8796977) 04 May 2020 (has links)
Autonomic control of the heart results in variations in the intervals between heart
beats, known as heart rate variability. One of the defining components of autonomic
control is the baroreflex, a negative feedback controller that balances heart rate and
blood pressure. The baroreflex is under constant command from the branches of the
autonomic nervous system. To better understand how the autonomic nervous system
commands the baroreflex, a baroreflex reflexogenic animal protocol was carried out.
Heart rate variability analysis and baroreflex sensitivity were used to quantify the
neural control of the heart. This thesis reconfirmed the existence of sexually dimorphic properties in the baroreflex through the use of heart rate variability analysis
and baroreflex sensitivity. It was discovered that there are many caveats to utilizing
heart rate variability analysis, which have to be addressed both in the experimental
protocol and the signal processing technique. Furthermore, it was suggested that the
slope method for quantifying baroreflex sensitivity also has many caveats, and that
other baroreflex sensitivity methods are likely more optimal for quantifying sustained
activation of the baroreflex. By utilizing various heart rate variability signal processing algorithms to assess autonomic tone in Sprague-Dawley rats during rest and
sustained electrical activation of the baroreflex, the null hypothesis was rejected.
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Dual-modality Photoacoustic and Ultrasound Imaging for Murine Atherosclerosis CharacterizationGurneet S Sangha (8066234) 05 December 2019 (has links)
Atherosclerosis accounts of 50% of the deaths in the western world leading to a plethora of diseases that include myocardial infarction, stroke, and peripheral artery disease. Currently available imaging modalities have inherent limitations, including ionizing radiation, lack of compositional information, and difficulty acquiring volumetric data that constrain their use in studying cardiovascular disease. Photoacoustic Tomography (PAT) has emerged as a promising modality that could address these limitations to improve the characterization and diagnosis of atherosclerosis-related conditions. Non-ionizing pulsed laser light is delivered to tissue leading to thermoelastic expansion followed by propagation of a pressure transient that can be detected with an ultrasound transducer. The magnitude of the ultrasonic PAT signal is proportional to the optical absorption at that location, revealing physiologically relevant compositional information of the tissue. The objective of this work is to therefore develop advanced volumetric imaging techniques to characterize disease progression in a murine model of atherosclerosis. The novelty of this work lies in the methodology and validation presented towards characterization of small animal vascular lipid accumulation with a high-resolution PAT system that utilizes the second near-infrared window (1100-1300nm). Additionally, we utilized <i>in situ </i>PAT to cross-sectionally assess lipid deposition and <i>in vivo</i>ultrasound to longitudinally assess hemodynamic, kinematic, and morphological changes during atherosclerosis progression. Together, this dissertation lays the foundation towards utilizing dual-modality PAT and ultrasound for various applications including understanding atherosclerosis pathophysiology, evaluation of novel therapeutics, and translation of clinically relevant techniques.
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ELECTRICAL BIOIMPEDANCE CEREBRAL MONITORING : A Study of Cerebral Impedance Variation / ÖVERVAKNING AV HJÄRNAN MED ELEKTRISK BIOIMPEDANS : En Studie om Cerebrala ImpedansändringarMokhberi, Shiva January 2016 (has links)
Stroke is amongst the leading causes of death and disability worldwide. Today diagnosis of Stroke is restricted to fixed imaging facilities which do not provide a rapid diagnostic. A portable device which could provide a non invasive assessment of stroke would therefore decrease the time of diagnosis and increase the chance of survival. Recent studies have confirmed that Implementing Electrical Bioimpedance in a portable device could provide a reliable means for Stroke diagnostic. However in order to be able to use the brain impedance as an indicator of Stroke, the invariance of brain impedance with time in healthy individuals should be studied first. Experimental Bioimpedance Spectroscopy (BIS) measurements from a healthy control group of 10 subjects have been used in this study to inspect the variation of brain impedance in the span of two weeks. The results of this study suggest that the cap which was used for brain impedance measurements together with the available device have not been an optimal way of measuring the brain impedance and therefore have affected the data by causing artifacts for the results. With the artifacts available in the data acquired in this study it is not possible to make any statements about the variation of brain impedance and therefore a deeper analysis of collected data using descriptive analysis is required in order to be able to judge on the significance of the obtained errors. In the future a larger study group should be considered in order to increase the predictive power of the observations. / Stroke är bland de ledande orsakerna till död och funktionshinder i hela världen.I dagsläget är diagnos av stroke begränsad till fasta bildenheter som inte möjliggör en snabb diagnos. En bärbar enhet som möjliggör en icke invasiv bedömning av sjukdomen skulle minska diagnos tiden och följaktligen öka chansen att överleva sjukdomen. Genomförda studier i ämnet har bekräftat att implementering av Electrical Bioimpedance i en bärbar enhet kan räknas som ett effektivt sätt för Stroke diagnostik. För att kunna använda hjärnans impedans för Stroke diagnostik, bör först en studie av hjärnans impedans på friska individer utföras för att kunna visa att impedansen är oförändrad med tiden. Experimentell Bioimpedans Spektroskopi (BIS) mätningar från en frisk kontrollgrupp av 10 försökspersoner har utförts i denna studie för att inspektera variationen av hjärnans impedans under två veckor. Resultaten från denna studie tyder på att sättet av impedans mätningen i dagsläget är inte optimalt. Artefakter presenterad i resultatet gör det omöjligt för att kunna komma till ett beslut om hjärnans impedans variation . För fortsätta studier bör man överväga en större kontrollgrupp och även en analysering av data med hjälp av t-statistik som var inte inom ramen av denna studie.
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DETECTION AND ISOLATION OF CIRCULATING TUMOR CELLS FROM WHOLE BLOOD USING A HIGH-THROUGHPUT MICROCHIP SYSTEMYuan Zhong (10695393) 29 April 2021 (has links)
<p>Circulating tumor cells (CTCs) have been
proved to possess great value and potential in detection, diagnosis, and <a>prognosis</a> of non-haematologic cancers. Their unique characteristics
in providing both phenotypic as well as genotypic information make them highly
valuable in liquid biopsy assays. A<a>t the same time, though
numerous studies and research have been done, identification and enumeration of
CTCs is still technically challenging due to their rarity and heterogeneity</a>.
The primary goal of the thesis is to develop a CTC detection and isolation system
with ultra-high
sensitivity and purity, while keeping it fast and scalable. We proposed a
microfluidic system that integrates
positive immunomagnetic capturing, high-throughput parallel flow and size
filtration. In this thesis, two generations of the system have been developed
to achieve the goal, and are approved to be able to effectively detect and
isolate CTCs from hundreds of breast cancer blood samples in real clinical
applications. </p>
<p>The first-generation system is based on a
sandwich-structured microfluidic chamber, which has a micro-aperture chip as
the core to detect and isolate immunomagnetically targeted CTCs. The system
achieves high detection yield (>95%) and purity (>99.9998% depletion of leukocytes) by streamlining the workflow and
using unprocessed whole blood (without centrifuging), as well as utilizing an
advanced surface coating approach to passivate the microchip surface. <a>We first demonstrate experiments for determining the optimal
detection parameters. Then we characterize the system by isolating deterministically
spiked 1, 10, and 100 single MCF-7 breast cancer cells into tubes of whole
blood, and show that >95% of cells were captured. A detection yield of 100%
from single cell spiking experiments (n = 6) demonstrates excellent detection
capability and repeatability of the system. We finally demonstrate the use of
the system for CTC detection in the context of a phase II clinical trial of
early-stage triple-negative breast cancer (TNBC) patients. As a part of the
trial, 182 blood samples were collected from 124 early-stage TNBC patients at
high-risk of relapse. We detected CTCs in 36.3% of patients who had already
completed chemotherapy and surgery for curative intent and were thus nominally
expected to have very few to zero CTCs. </a>Moreover, increasing CTC count from the
same patients shows good correlation with <a></a><a>their clinical course</a>. The ability to detect CTCs’ presence using this first-generation
system illustrates its important clinical utility.</p>
<p>The second-generation system applies a similar
detection strategy but employs an upgraded microchip and device, as well as a
further streamlined process flow to achieve an even higher detection efficiency,
especially for capturing the target cells with low surface marker expression
level. We first did modeling and simulation of the new system to find the optimal
magnet configuration and verify the detection sensitivity improvement on the
first-generation system. Then we characterized the new system by detecting
spiked JEG-3 and JAR cells in both cell culture medium and human blood. The
result demonstrates that the detection yield increased by ~20% using the
second-generation system under the same experiment condition. Next, we applied
the system to a phase I clinical trial for CTC detection from metastatic triple-negative breast cancer (mTNBC) patient blood samples. CTCs of mTNBC
are known to with in the low marker expression phenotype, which requires
ultra-high detection sensitivity. Our system captured CTCs from 48 out of 102
(47%) blood samples, the positivity rate agrees with the conclusions from other
studies and presents the reliability to the system. Finally, we explored a
novel 4-marker panel for CTC detection from mTNBC patient blood samples. We
conducted paired comparisons using the 4-marker panel versus a single marker
for detection. The 4-marker panel yielded more CTCs in 5/8 complete paired assessments,
and less CTCs in 1/8. The association missed the significance level only
slightly (p = 0.08), and the result strongly illustrates the potential for
using the panel to cover the mTNBC cells’ heterogeneity for enhanced CTC
detection. Furthermore, the presence of CTCs from blood samples correlates well
with the patient’s disease progression.</p>
<p>Finally, we demonstrated downstream analysis ability
of the CTCs detected by the second-generation system. Captured CTCs can be
readily released from our system without any loss or damage to a secondary
microchip device to be further isolated as single cells, and picked up
individually for downstream analysis like DNA/RNA sequencing or single-cell cultivation.
Directions for future work is also discussed. We envision this versatile and
efficient system to be highly beneficial in a broad range of clinical and
research applications regarding CTCs.</p>
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