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1.
Yonsei Med J ; 65(6): 363-370, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38804031

RESUMO

PURPOSE: We investigated the association between social support, metabolic syndrome, and incident cardio-cerebrovascular disease (CCVD) in rural Koreans aged ≥50 years. MATERIALS AND METHODS: We conducted a prospective study using the Korean Genome and Epidemiology Study on Atherosclerosis Risk of Rural Areas in the Korean General Population (KoGES-ARIRANG) dataset. From the baseline of 5169 adults, 1682 participants were finally included according to the exclusion criteria. For outcomes, myocardial infarction, angina, and stroke were included. For independent variables, the social support score and metabolic syndrome were used. Descriptive statistics and multivariate logistic regression were performed to investigate the association among the variables. Paired t-test was conducted to analyze the longitudinal variation of social support scores. RESULTS: During the 6.37 years of median follow-up, 137 participants developed CCVD. The adjusted odds ratio (aOR) of metabolic syndrome with persistently high social support was 2.175 [95% confidence interval (CI): 1.479-3.119]. The aOR of metabolic syndrome with persistently low social support was 2.494 (95% CI: 1.141-5.452). The longitudinal variation of the social support score of persistently high social support group was increased significantly by 4.26±26.32. The score of the persistently low social support group was decreased by 1.34±16.87 with no statistical significance. CONCLUSION: The presence of metabolic syndrome increases the likelihood of developing onset CCVD. Within the metabolic syndrome positive group, when social support was persistently low, the cohort developed more cardio-cerebrovascular disease compared to the persistently higher social support group. The social support score of the persistently low social support group could be improved through proper intervention. To prevent CCVD, metabolic syndrome components and low social support should be improved in the study participants.


Assuntos
Transtornos Cerebrovasculares , Síndrome Metabólica , Apoio Social , Humanos , Síndrome Metabólica/epidemiologia , Feminino , Masculino , Pessoa de Meia-Idade , Transtornos Cerebrovasculares/epidemiologia , Idoso , Estudos Prospectivos , Incidência , República da Coreia/epidemiologia , Fatores de Risco , Doenças Cardiovasculares/epidemiologia , População Rural/estatística & dados numéricos , Modelos Logísticos , Razão de Chances
2.
J Korean Med Sci ; 38(34): e267, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37644682

RESUMO

BACKGROUND: This study aimed to determine whether serum uric acid (SUA) levels are associated with various indices of liver damage in the adult Korean population. METHODS: We used the Seventh (VII) Korean National Health and Nutritional Examination Surveys. Our study population comprised 6,007 men and 8,488 women. Levels of SUA were divided into four groups (≤ 5.3, 5.3-6.0, 6.0-7.0, and > 7.0 mg/dL for men and ≤ 4.0, 4.0-4.8, 4.8-6.0, and > 6.0 mg/dL for women). Elevated liver enzyme levels were defined as > 35 (men) and > 31 (women) IU/L for aspartate aminotransferase (AST), > 45 (men) and > 34 (women) IU/L for alanine aminotransferase (ALT). Hepatic steatosis index and fibrosis (FIB)-4 index was used to determine nonalcoholic fatty liver disease (NAFLD) and liver FIB, respectively. Adjusted odds ratios (aORs) were calculated by logistic regression analysis for liver enzymes, NAFLD, and liver FIB, according to the SUA level. RESULTS: Among women, the 4.8-6.0 and > 6.0 mg/dL SUA groups showed higher ORs of elevated AST (aOR, 1.78 and 2.03; 95% confidence interval [CI], 1.37-2.32 and 1.40-2.96, respectively; P < 0.001) and the 4.0-4.8, 4.8-6.0, and > 6.0 mg/dL SUA groups showed a higher ORs of ALT elevation (aOR, 1.35, 2.26, and 2.37; 95% CI, 1.02-1.79, 1.72-2.97, and 1.60-3.50, respectively; P < 0.001) compared to the lowest level SUA group. Among women with normal ALT, > 6.0 mg/dL SUA group showed higher OR of NAFLD status (aOR, 1.52; 95% CI, 1.06-2.19). Among men and women with NAFLD, hyperuricemia showed higher ORs of liver FIB (aOR, 2.25 and 1.89; 95% CI, 1.21-4.19 and 1.09-3.27, respectively) than the lowest level SUA group. CONCLUSION: High SUA levels may be associated with elevated liver enzymes and NAFLD, mainly in women. Even in women with normal ALT levels, SUA levels may predict the NAFLD status. Hyperuricemia may predict advanced liver FIB in both men and women with NAFLD. Further studies investigating the causal effects of SUA on liver damage are required.


Assuntos
Hiperuricemia , Hepatopatia Gordurosa não Alcoólica , Adulto , Masculino , Humanos , Feminino , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Ácido Úrico , Estudos Transversais , Hiperuricemia/diagnóstico , Hiperuricemia/epidemiologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/etiologia , República da Coreia/epidemiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-37569077

RESUMO

This study aimed to evaluate the impact of parental mental health on adolescent offspring. Data regarding 6512 families from the 2010-2021 Korean National Health and Nutrition Examination Survey were analyzed; among them, 428 were placed in the suicidal ideation (SI) group and 421 were placed in the matched control (MC) group. This number was selected for the use of the propensity score matching method. The findings highlighted significant associations between parental mental health and adolescent suicidal ideation, with mothers in the SI group having higher odds of Diagnosed Depression (OR 2.109, 1.023-4.350 95% CI), Depressive Mood (OR 2.155, 1.224-3.793 95% CI), and Suicidal Ideation (OR 2.532, 1.322-4.851 95% CI) compared to the MC group. Regarding the fathers, paternal Suicidal Ideation (OR 4.295, 1.747-10.599 95% CI) was the only significant factor for adolescent suicidal ideation. In contrast, maternal depressive symptoms and help-seeking behavior significantly impacted adolescent help-seeking; Maternal Depressive Mood increased with adolescent Help-Seeking (OR 4.486, 1.312-15.340 95% CI) while Maternal Suicidal Ideation reduced the probability of Help-Seeking in the SI group (OR 0.15, 0.031-0.721, 95% CI). Chronic and severe depressive symptoms in mothers could make adolescents less likely to seek help for their suicidal ideations. Therefore, clinicians working with adolescents should prioritize a family-oriented approach.


Assuntos
Comportamento de Busca de Ajuda , Ideação Suicida , Masculino , Feminino , Humanos , Adolescente , Depressão/epidemiologia , Depressão/psicologia , Inquéritos Nutricionais , Saúde Mental , Mães/psicologia
4.
Saf Health Work ; 14(1): 71-77, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36941935

RESUMO

Background: This study investigated the relationship between trauma exposure and suicidal ideation. Moreover, this study examines the moderating roles of organizational climate on the association between trauma exposure and suicidal ideation in Korean male firefighters. Methods: A total of 15,104 male firefighters who completed a questionnaire were analyzed. The data were obtained using an online self-administered questionnaire from the Firefighter Research on Enhancement of Safety and Health Study. Poisson regression analysis was performed to determine the effects of trauma exposure on suicidal ideation and the moderating effect of organizational climate. Results: The results showed that 389 firefighters (2.6%) responded that they had experienced suicidal ideation. In the final model, trauma exposure was positively related to suicidal ideation (adjusted risk ratio [aRR], 1.076; 95% confidence interval [CI]: 1.051-1.103), and organizational climate was negatively associated with suicidal ideation (aRR, 0.772; 95% CI: 0.739-0.806). Additionally, the interaction term (trauma exposure × organizational climate) was related to suicidal ideation (aRR, 1.016; 95% CI: 1.009-1.023). Conclusions: This study suggests that trauma exposure might play a significant role in developing suicidal ideation and that positive organizational climate moderates the negative effects of trauma exposure on suicidal ideation among firefighters. It is necessary to perform a follow-up study of various intervention strategies to maintain a healthy organizational climate or work environment. Such interventions should promote lasting trust within teams, provide social support and belonging, and nurture job value.

5.
Micromachines (Basel) ; 13(12)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36557481

RESUMO

The ultrasonic actuator can be used in medical applications because it is label-free, biocompatible, and has a demonstrated history of safe operation. Therefore, there is an increasing interest in using an ultrasonic actuator in the non-contact manipulation of micromachines in various materials and sizes for therapeutic applications. This research aims to design, fabricate, and characterize a single-sided transducer array with 56 channels operating at 500 kHz, which provide benefits in the penetration of tissue. The fabricated transducer is calibrated using a phase reference calibration method to reduce position misalignment and phase discrepancies caused by acoustic interaction. The acoustic fields generated by the transducer array are measured in a 300 mm × 300 mm × 300 mm container filled with de-ionized water. A hydrophone is used to measure the far field in each transducer array element, and the 3D holographic pattern is analyzed based on the scanned acoustic pressure fields. Next, the phase reference calibration is applied to each transducer in the ultrasonic actuator. As a result, the homogeneity of the acoustic pressure fields surrounding the foci area is improved, and the maximum pressure is also increased in the twin trap. Finally, we demonstrate the capability to trap and manipulate micromachines with acoustic power by generating a twin trap using both optical camera and ultrasound imaging systems in a water medium. This work not only provides a comprehensive study on acoustic actuators but also inspires the next generation to use acoustics in medical applications.

6.
Sci Adv ; 8(46): eabq8545, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36399561

RESUMO

Microrobots that can be precisely guided to target lesions have been studied for in vivo medical applications. However, existing microrobots have challenges in vivo such as biocompatibility, biodegradability, actuation module, and intra- and postoperative imaging. This study reports microrobots visualized with real-time x-ray and magnetic resonance imaging (MRI) that can be magnetically guided to tumor feeding vessels for transcatheter liver chemoembolization in vivo. The microrobots, composed of a hydrogel-enveloped porous structure and magnetic nanoparticles, enable targeted delivery of therapeutic and imaging agents via magnetic guidance from the actuation module under real-time x-ray imaging. In addition, the microrobots can be tracked using MRI as postoperative imaging and then slowly degrade over time. The in vivo validation of microrobot system-mediated chemoembolization was demonstrated in a rat liver with a tumor model. The proposed microrobot provides an advanced medical robotic platform that can overcome the limitations of existing microrobots and current liver chemoembolization.


Assuntos
Neoplasias Hepáticas , Robótica , Humanos , Imageamento por Ressonância Magnética , Magnetismo , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia
7.
Pharmaceutics ; 14(10)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36297578

RESUMO

Targeted drug delivery using microrobots manipulated by an external actuator has significant potential to be a practical approach for wireless delivery of therapeutic agents to the targeted tumor. This work aimed to develop a novel acoustic manipulation system and macrophage-based microrobots (Macbots) for a study in targeted tumor therapy. The Macbots containing superparamagnetic iron oxide nanoparticles (SPIONs) can serve as drug carriers. Under an acoustic field, a microrobot cluster of the Macbots is manipulated by following a predefined trajectory and can reach the target with a different contact angle. As a fundamental validation, we investigated an in vitro experiment for targeted tumor therapy. The microrobot cluster could be manipulated to any point in the 4 × 4 × 4 mm region of interest with a position error of less than 300 µm. Furthermore, the microrobot could rotate in the O-XY plane with an angle step of 45 degrees without limitation of total angle. Finally, we verified that the Macbots could penetrate a 3D tumor spheroid that mimics an in vivo solid tumor. The outcome of this study suggests that the Macbots manipulated by acoustic actuators have potential applications for targeted tumor therapy.

8.
Yonsei Med J ; 63(8): 774-782, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35914760

RESUMO

PURPOSE: The characteristic topography and climate often affect the occurrence of large-scale wildfires in the Eastern Gangwon-do region of Korea. However, there are no studies on the health effects of these wildfires in Korea. This study aimed to analyze the differences in medical use between a wildfire-affected area and an adjacent non-affected area before and after a wildfire in 2019 in Gangwon-do, Korea. MATERIALS AND METHODS: We used medical usage data from the Korean National Health Insurance Corporation. Rates of medical use were determined for citizens of a wildfire-affected area in the Eastern Yeongdong region and a non-affected area in the Western Yeongseo region. Logistic regression analysis was performed considering an increase in medical use per individual as a dependent variable; age, sex, income, smoking, drinking, and exercise were included as confounding variables. RESULTS: The odds ratio for medical use in Yeongdong region increased significantly after 3 days, 3 months, and 1 year after a fire occurred, compared with Yeongseo region. CONCLUSION: The results of this study confirmed that the use of medical care increased for residents of a wildfire-affected area, compared with those of an adjacent non-affected area. This is the first study on the relationship between wildfires and inpatient medical use in Korea.


Assuntos
Incêndios Florestais , Exercício Físico , Humanos , Renda , Razão de Chances , Fumaça/efeitos adversos
9.
Pharmaceutics ; 14(7)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35890382

RESUMO

Acoustic tweezers provide unique capabilities in medical applications, such as contactless manipulation of small objects (e.g., cells, compounds or living things), from nanometer-sized extracellular vesicles to centimeter-scale structures. Additionally, they are capable of being transmitted through the skin to trap and manipulate drug carriers in various media. However, these capabilities are hindered by the limitation of controllable degrees of freedom (DoFs) or are limited maneuverability. In this study, we explore the potential application of acoustical tweezers by presenting a five-DoF contactless manipulation acoustic system (AcoMan). The system has 30 ultrasound transducers (UTs) with single-side arrangement that generates active traveling waves to control the position and orientation of a fully untethered nanocarrier clusters (NCs) in a spherical workspace in water capable of three DoFs translation and two DoFs rotation. In this method, we use a phase modulation algorithm to independently control the phase signal for 30 UTs and manipulate the NCs' positions. Phase modulation and switching power supply for each UT are employed to rotate the NCs in the horizontal plane and control the amplitude of power supply to each UT to rotate the NCs in the vertical plane. The feasibility of the method is demonstrated by in vitro and ex vivo experiments using porcine ribs. A significant portion of this study could advance the therapeutic application such a system as targeted drug delivery.

10.
Brief Bioinform ; 23(4)2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35753701

RESUMO

Advances in whole-genome sequencing (WGS) promise to enable the accurate and comprehensive structural variant (SV) discovery. Dissecting SVs from WGS data presents a substantial number of challenges and a plethora of SV detection methods have been developed. Currently, evidence that investigators can use to select appropriate SV detection tools is lacking. In this article, we have evaluated the performance of SV detection tools on mouse and human WGS data using a comprehensive polymerase chain reaction-confirmed gold standard set of SVs and the genome-in-a-bottle variant set, respectively. In contrast to the previous benchmarking studies, our gold standard dataset included a complete set of SVs allowing us to report both precision and sensitivity rates of the SV detection methods. Our study investigates the ability of the methods to detect deletions, thus providing an optimistic estimate of SV detection performance as the SV detection methods that fail to detect deletions are likely to miss more complex SVs. We found that SV detection tools varied widely in their performance, with several methods providing a good balance between sensitivity and precision. Additionally, we have determined the SV callers best suited for low- and ultralow-pass sequencing data as well as for different deletion length categories.


Assuntos
Benchmarking , Genoma Humano , Animais , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Camundongos , Sequenciamento Completo do Genoma/métodos
11.
J Mater Chem B ; 10(23): 4509-4518, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35616358

RESUMO

Stomach cancer is a global health concern as millions of cases are reported each year. In the present study, we developed a pH-responsive microrobot with good biocompatibility, magnetic-field controlled movements, and the ability to be visualized via X-ray imaging. The microrobot consisted of composite resin and a pH-responsive layer. This microrobot was found to fold itself in high pH environments and unfold itself in low pH environments. In addition, the neodymium (NdFeB) magnetic nanoparticles present inside the composite resin provided the microrobot with an ability to be controlled by a magnetic field through an electromagnetic actuation system, and the monomeric triiodobenzoate-based particles were found to act as contrast agents for real-time X-ray imaging. The doxorubicin coating on the microrobot's surface resulted in a high cancer-cell killing effect. Finally, we demonstrated the proposed microrobot under an ex vivo environment using a pig's stomach. Thus, this approach can be a potential alternative to targeted drug carriers, especially for stomach cancer applications.


Assuntos
Neoplasias Gástricas , Resinas Compostas , Doxorrubicina/farmacologia , Humanos , Magnetismo , Neoplasias Gástricas/diagnóstico por imagem , Raios X
12.
ACS Sens ; 7(2): 632-640, 2022 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-35147414

RESUMO

Embedded sensors for endoscopy devices have been studied toward a convenient and decision-supportive methodology in colorectal cancer (CRC) diagnosis, but no device could provide direct CRC screening with in situ measurements. In this study, we proposed a millimeter-scale electrical impedance spectroscopy (EIS) device that can be integrated into a biopsy tool in endoscopy for colorectal tumor detection. A minimally invasive tripolar electrode was designed to sense the tissue impedance, and a multilayer neural network was implemented for the classification algorithm. The sensor performance was investigated in terms of sensitivity, reliability, and repeatability using dummy tissues made of agarose hydrogels at various saline concentrations. In addition, an in vivo study was conducted in mice with an implanted CT-26 colon tumor line. The results demonstrated that the prototyped EIS device and algorithm can detect the tumor tissue in suspicious lesions with high sensitivity and specificity of 87.2 and 92.5%, respectively, and a low error of 7.1%. The findings of this study are promising for in situ CRC screening and may advance the diagnostic efficacy of CRC detection during endoscopic procedures.


Assuntos
Neoplasias Colorretais , Espectroscopia Dielétrica , Animais , Neoplasias Colorretais/diagnóstico , Espectroscopia Dielétrica/métodos , Detecção Precoce de Câncer/métodos , Eletrodos , Camundongos , Reprodutibilidade dos Testes
13.
Genes (Basel) ; 13(2)2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35205218

RESUMO

Alcohol consumption can increase the risk of chronic diseases, such as myocardial infarction, coronary artery disease, hyperlipidemia, and hypertension. We aimed to assess the association between genotype, DNA methylation patterns, alcohol consumption, and chronic diseases in Korean population. We analyzed 8840 subjects for genotypes and 446 for DNA methylation among the 9351 subjects from the Korean Genome and Epidemiology Study (KoGES). We further divided both groups into two sub-groups according to the presence/absence of chronic diseases. We selected genes whose methylation varied significantly with alcohol consumption, and visualized genotype and DNA methylation patterns specific to each group. Genome-wide association study (GWAS) revealed single nucleotide polymorphisms (SNPs) rs2074356 and rs11066280 in HECT domain E3 ubiquitin protein ligase 4 (HECTD4) to be significantly associated with alcohol consumption in both the presence. The rs12229654 genotype also displayed significantly different patterns with alcohol consumption. Furthermore, we retrieved differentially methylated regions (DMRs) from four groups based on sex and chronic diseases and compared them by drinking status. In genotype analysis, cardiovascular diseases (CVDs) showed a higher proportion in drinker than in non-drinker, but not in DMR analysis. Additionally, we analyzed the enriched Gene Ontology terms and Kyoto Gene and Genome Encyclopedia (KEGG) pathways and visualized the network, heatmap, and upset plot. We show that the pattern of DNA methylation associated with CVD is strongly influenced by alcoholism. Overall, this study identified genetic and epigenetic variants influenced by alcohol consumption and chronic diseases.


Assuntos
Doenças Cardiovasculares , Metilação de DNA , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/genética , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , República da Coreia/epidemiologia
14.
J Occup Environ Med ; 64(6): 510-514, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35081586

RESUMO

OBJECTIVES: This study aimed to examine the effects of firefighters' emergency duties on the incidence of cardiovascular disease (CVD). METHODS: We used a 13-year follow-up in a nationwide retrospective cohort study. A total of 363,137 employees were recruited. The sex-and age-specific incidence of CVD (hypertension, angina pectoris, and acutemyocardial infarction [AMI]) in firefighters and public officials was estimated. RESULTS: The overall age-specific sex-based incidence of CVD, except for hypertension, was higher in firefighters than in public officials. The age-stratified hazard ratios for the three types of CVD in male firefighters were also higher. AMI was more common in younger firefighters, whereas angina pectoris and hypertension were common in older firefighters. CONCLUSIONS: Firefighters' duties are more likely to increase the risk of CVD, and preventive strategies with proven benefits are required.


Assuntos
Doenças Cardiovasculares , Bombeiros , Hipertensão , Idoso , Angina Pectoris/epidemiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Humanos , Hipertensão/epidemiologia , Masculino , Estudos Retrospectivos , Fatores de Risco
15.
J Korean Med Sci ; 36(50): e335, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34962111

RESUMO

BACKGROUND: Firefighters inevitably encounter emotionally and physically stressful situations at work. Even firefighters without diagnosed post-traumatic stress disorder receive clinical attention because the nature of the profession exposes them to repetitive trauma and high occupational stress. This study investigated gray matter abnormalities related to high occupational stress in firefighters using voxel-based morphometry (VBM) and surface-based morphometry (SBM). METHODS: We assessed 115 subjects (112 males and 3 females) using magnetic resonance imaging and evaluated occupational stress by the Korean Occupational Stress Scale-26 (KOSS-26). Subjects were classified into highly or lowly stressed groups based on the median value of the KOSS-26. RESULTS: In VBM analysis, we found that firefighters with high occupational stress had lower gray matter volume (GMV) in both sides of the insula, the left amygdala, the right medial prefrontal cortex (mPFC), and the anterior cingulate cortex than firefighters with low occupational stress. In SBM analysis based on regions of interest, the GMV of the bilateral insula and right mPFC were also lower in the highly stressed group. Within the highly stressed group, low GMV of the insula was significantly correlated with the length of service (left: r = -0.347, P = 0.009; right: r = -0.333, P = 0.012). CONCLUSION: Our findings suggest that regional GMV abnormalities are related to occupational stress. Regional gray matter abnormalities and related emotional dysregulation may contribute to firefighter susceptibility to burnout.


Assuntos
Bombeiros , Estresse Ocupacional , Córtex Cerebral , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino
16.
Pharmaceutics ; 13(10)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34683982

RESUMO

Various cell therapy strategies, including chimeric antigen receptor-expressing T or natural killer (NK) cells and cell-mediated drug delivery, have been developed for tumor eradication. However, the efficiency of these strategies against solid tumors remains unclear. We hypothesized that real-time control and visualization of therapeutic cells, such as NK cells, would improve their therapeutic efficacy against solid tumors. In this study, we engineered Sonazoid microbubble-conjugated NK (NK_Sona) cells and demonstrated that they were detectable by ultrasound imaging in real-time and maintained their functions. The Sonazoid microbubbles on the cell membrane did not affect the cytotoxicity and viability of the NK cells in vitro. Additionally, the NK_Sona cells could be visualized by ultrasound imaging and inhibited tumor growth in vivo. Taken together, our findings demonstrate the feasibility of this new approach in the use of therapeutic cells, such as NK cells, against solid tumors.

17.
Diagnostics (Basel) ; 11(10)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34679575

RESUMO

This paper presents an active locomotion capsule endoscope system with 5D position sensing and real-time automated polyp detection for small-bowel and colon applications. An electromagnetic actuation system (EMA) consisting of stationary electromagnets is utilized to remotely control a magnetic capsule endoscope with multi-degree-of-freedom locomotion. For position sensing, an electronic system using a magnetic sensor array is built to track the position and orientation of the magnetic capsule during movement. The system is integrated with a deep learning model, named YOLOv3, which can automatically identify colorectal polyps in real-time with an average precision of 85%. The feasibility of the proposed method concerning active locomotion and localization is validated and demonstrated through in vitro experiments in a phantom duodenum. This study provides a high-potential solution for automatic diagnostics of the bowel and colon using an active locomotion capsule endoscope, which can be applied for a clinical site in the future.

18.
Adv Healthc Mater ; 10(19): e2100068, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34369079

RESUMO

Various magnetic microcarrier systems capable of transporting cells to target lesions are developed for therapeutic agent-based tissue regeneration. However, the need for bioactive molecules and cells, the potential toxicity of the microcarrier, and the large volume and limited workspace of the magnetic targeting device remain challenging issues associated with microcarrier systems. Here, a multifunctional magnetic implant system is presented for targeted delivery, secure fixation, and induced differentiation of stem cells. This magnetic implant system consists of a biomaterial-based microcarrier containing bioactive molecules, a portable magnet array device, and a biocompatible paramagnetic implant. Among biomedical applications, the magnetic implant system is developed for knee cartilage repair. The various functions of these components are verified through in vitro, phantom, and ex vivo tests. As a result, a single microcarrier can load ≈1.52 ng of transforming growth factor ß (TGF-ß1) and 3.3 × 103 of stem cells and stimulate chondrogenic differentiation without extra bioactive molecule administration. Additionally, the implant system demonstrates high targeting efficiency (over 90%) of the microcarriers in a knee phantom and ex vivo pig knee joint. The results show that this implant system, which overcomes the limitations of the existing magnetic targeting system, represents an important advancement in the field.


Assuntos
Células-Tronco Mesenquimais , Animais , Diferenciação Celular , Células Cultivadas , Condrogênese , Células-Tronco , Suínos
19.
Sci Rep ; 11(1): 15122, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34302003

RESUMO

Magnetic nanorobots (MNRs) based on paramagnetic nanoparticles/nanoclusters for the targeted therapeutics of anticancer drugs have been highlighted for their efficiency potential. Controlling the locomotion of the MNRs is a key challenge for effective delivery to the target legions. Here, we present a method for controlling paramagnetic nanoclusters through enhanced tumbling and disaggregation motions with a combination of rotating field and gradient field generated by external electromagnets. The mechanism is carried out via an electromagnetic actuation system capable of generating MNR motions with five degrees of freedom in a spherical workspace without singularity. The nanocluster swarm structures can successfully pass through channels to the target region where they can disaggregate. The results show significantly faster response and higher targeting rate by using rotating magnetic and gradient fields. The mean velocities of the enhanced tumbling motion are twice those of the conventional tumbling motion and approximately 130% higher than the gradient pulling motion. The effects of each fundamental factor on the locomotion are investigated for further MNR applications. The locomotion speed of the MNR could be predicted by the proposed mathematical model and agrees well with experimental results. The high access rate and disaggregation performance insights the potentials for targeted drug delivery application.

20.
Comput Med Imaging Graph ; 92: 101956, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34315034

RESUMO

Automated three-dimensional (3D) blood vessel reconstruction to improve vascular diagnosis and therapeutics is a challenging task in which the real-time implementation of automatic segmentation and specific vessel tracking for matching artery sequences is essential. Recently, a deep learning-based segmentation technique has been proposed; however, existing state-of-the-art deep architectures exhibit reduced performance when they are employed using real in-vivo imaging because of serious issues such as low contrast and noise contamination of the X-ray images. To overcome these limitations, we propose a novel methodology composed of the de-haze image enhancement technique as pre-processing and multi-level thresholding as post-processing to be applied to the lightweight multi-resolution U-shaped architecture. Specifically, (1) bi-plane two-dimensional (2D) vessel images were extracted simultaneously using the deep architecture, (2) skeletons of the vessels were computed via a morphology operation, (3) the corresponding skeleton structure between image sequences was matched using the shape-context technique, and (4) the 3D centerline was reconstructed using stereo geometry. The method was validated using both in-vivo and in-vitro models. The results show that the proposed technique could improve the segmentation quality, reduce computation time, and reconstruct the 3D skeleton automatically. The algorithm accurately reconstructed the phantom model and the real mouse vessel in 3D in 2 s. Our proposed technique has the potential to allow therapeutic micro-agent navigation in clinical practice, thereby providing the 3D position and orientation of the vessel.


Assuntos
Angiografia , Imageamento Tridimensional , Algoritmos , Animais , Aumento da Imagem , Camundongos
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