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Auditory Brainstem Response (ABR) is an evoked potential in the brainstem's neural centers in response to sound stimuli. Clinically, characteristic waves, especially Wave V latency, extracted from ABR can objectively indicate auditory loss and diagnose diseases. Several methods have been developed for the extraction of characteristic waves. To ensure the effectiveness of the method, most of the methods are time-consuming and rely on the heavy workloads of clinicians. To reduce the workload of clinicians, automated extraction methods have been developed. However, the above methods also have limitations. This study introduces a novel deep learning network for automatic extraction of Wave V latency, named ABR-Attention. ABR-Attention model includes a self-attention module, first and second-derivative attention module, and regressor module. Experiments are conducted on the accuracy with 10-fold cross-validation, the effects on different sound pressure levels (SPLs), the effects of different error scales and the effects of ablation. ABR-Attention shows efficacy in extracting Wave V latency of ABR, with an overall accuracy of 96.76±0.41% and an error scale of 0.1ms, and provides a new solution for objective localization of ABR characteristic waves.
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BACKGROUND: Irregular sleep patterns have been associated with inflammation. Galectin-3, a novel biomarker, plays an important role in inflammation. We investigated the relationship between sleep patterns and galectin-3 in a Chinese population. METHODS: A total of 1,058 participants from the Shenzhen-Hong Kong United Network on Cardiovascular Disease study were included in the analysis. Age and sex-adjusted linear regression models were employed to investigate the relationship between galectin-3 level and traditional metabolic biomarkers. Logistic regression models were used to estimate the association among sleep disturbance, nighttime sleep duration, and daytime napping duration and elevated galectin-3, with elevated galectin-3 defined as galectin-3 level > 65.1 ng/ml. RESULTS: Of study participants, the mean age was 45.3 years and 54.3% were women. Waist circumference, natural logarithm (ln)-transformed triglyceride, and ln-transformed high sensitivity C-reactive protein were positively associated with galectin-3 level (age and sex-adjusted standardized ß [95% confidence interval (CI)], 0.12 [0.04, 0.21], 0.11 [0.05, 0.17], and 0.08 [0.02, 0.14], respectively). Sleep disturbance was associated with elevated galectin-3 (odds ratio [95% CI], 1.68 [1.05, 2.68], compared to those without sleep disturbance) after adjusting for traditional metabolic biomarkers. No interaction was observed between galectin-3 and age, sex, obesity, hypertension, and diabetes on sleep disturbance. No association was found between nighttime sleep duration or daytime napping duration and elevated galectin-3. CONCLUSIONS: Our study provides evidence of a significant association between sleep disturbance and elevated galectin-3 level, independent of traditional metabolic biomarkers. Screening and interventions on galectin-3 could assist in preventing sleep disturbance-induced inflammatory disease.
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Biomarcadores , Galectina 3 , Transtornos do Sono-Vigília , Sono , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Galectina 3/sangue , Biomarcadores/sangue , Adulto , Sono/fisiologia , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/sangue , China/epidemiologia , Hong Kong/epidemiologia , População do Leste AsiáticoRESUMO
Falls occur frequently in daily life and the damage to the body is irreversible. Therefore, it is crucial to implement timely and effective warning and protection systems for falls to minimize the damage caused by falls. Currently, the fall warning algorithm has shortcomings such as low recognition rates for falls and fall-risk movements and insufficient lead-time, the time before the subject impacts the floor, making it difficult for falling protection devices to function effectively. In this study, a multi-scale falls warning algorithm based on offset displacement is built, and a hip protection system is designed. The performance of the algorithm and the system is validated using 150 falling and 500 fall-risk actions from 10 volunteers. The results showed that the recognition accuracy for falling actions is 98.7% and the recognition accuracy for fall-risk actions is 99.4%, with an average lead-time of 402ms. The protection rate for falling movements reached 98.7%. This proposed algorithm and hip protection system have the potential to be applied in elderly communities, hospitals, and homes to reduce the damage caused by falls.Clinical Relevance- This study provides important reference for clinicians in analyzing fall behaviors to patients at risk of falls in clinical settings, offering valuable technical support for ensuring the safety of patients in danger of falling. It also contributes to further promoting the development of falling-prevention medical devices.
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Acidentes por Quedas , Hospitais , Humanos , Idoso , Acidentes por Quedas/prevenção & controle , MovimentoRESUMO
INTRODUCTION: Lifestyle factors are known to play a role in the development of hypertension. We aimed to study the relationship between lifestyle and hypertension in a Chinese population. METHODS: This study involved 3,329 participants (1,463 men and 1,866 women) aged 18-96 years in the Shenzhen-Hong Kong United Network on Cardiovascular Disease. A healthy lifestyle score was derived from 5 factors: no smoking, no alcohol consumption, active physical activity, normal body mass index, and a healthy diet. Multiple logistic regression was used to investigate the relationship between lifestyle score and hypertension. The influence of each lifestyle component on hypertension was also assessed. RESULTS: In the overall population, 950 (28.5%) participants had hypertension. The risk of hypertension decreased with increasing healthy lifestyle scores. Compared with participants with the lowest score (score: 0), the multivariable odds ratios (ORs) and corresponding 95% confidence intervals for participants with scores 3, 4, and 5 were 0.65 (0.41-1.01), 0.62 (0.40-0.97), and 0.37 (0.22-0.61), respectively (P for trend <0.001). After adjusting for age, sex, and diabetes, the score was associated with hypertension risk (P for trend = 0.005). Compared with a lifestyle score of 0, the adjusted OR for hypertension for participants with a score of 5 was 0.46 (0.26-0.80). CONCLUSIONS: The risk of hypertension is inversely related to the healthy lifestyle score. This reinforces the need to address lifestyle to reduce the risk of hypertension.
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Doenças Cardiovasculares , Hipertensão , Masculino , Humanos , Feminino , Doenças Cardiovasculares/epidemiologia , Hipertensão/epidemiologia , Estilo de Vida Saudável , Fumar/epidemiologia , Estilo de Vida , China/epidemiologia , Fatores de RiscoRESUMO
INTRODUCTION: Beta-2-microglobulin (B2M), cystatin C and lipocalin-2 (LCN-2) are established renal biomarkers, yet their roles in stroke have not been fully evaluated. We aimed to investigate the relationship of B2M, cystatin C, and LCN-2 with stroke risk in a general Chinese population. METHODS: We used ordinal regression to study the relationship between serum B2M, cystatin C, and LCN-2 with stroke risk in 1060 participants (mean age 45.4 ± 10.8 years, 46% male) from the Shenzhen-Hong Kong United Network on Cardiovascular Disease (SHUN-CVD) study. Stroke risk was classified into low-risk, middle-risk and high-risk groups according to the China National Stroke Screening Survey criteria. Serum biomarker levels were measured using immunoturbidimetric assays. Participants with valid data on serum biomarker levels and stroke risk were included in the analysis. RESULTS: The number of participants in the low-risk, middle-risk and high-risk stroke risk groups were 663, 143 and 254 respectively. Elevated serum B2M, cystatin C, and LCN-2 levels were associated with being male, overweight/obesity, hypertension, alcohol consumption and smoking. Serum B2M, cystatin C and LCN-2 levels were significantly associated with stroke risk in the overall population (B2M: ß = 0.595, p < .001; cystatin C: ß = 3.718, p < .001; LCN-2: ß = 0.564, p < .001) after adjustment for age. CONCLUSION: Elevated serum B2M, cystatin C and LCN-2 levels are associated with stroke risk. They may be novel biomarkers for clinicians to assess stroke risk.Key messagesSerum beta-2-microglobulin, cystatin C and lipocalin-2 levels are significantly associated with stroke risk.Beta-2-microglobulin, cystatin C and lipocalin-2 may serve as useful biomarkers for stroke risk stratification in the general population.
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Cistatina C , Acidente Vascular Cerebral , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Feminino , Lipocalina-2 , População do Leste Asiático , Biomarcadores , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , CreatininaRESUMO
Objective.Prosthetic systems are used to improve the quality of life of post-amputation patients, and research on surface electromyography (sEMG)-based gesture classification has yielded rich results. Nonetheless, current gesture classification algorithms focus on the same subject, and cross-individual classification studies that overcome physiological factors are relatively scarce, resulting in a high abandonment rate for clinical prosthetic systems. The purpose of this research is to propose an algorithm that can significantly improve the accuracy of gesture classification across individuals.Approach.Eight healthy adults were recruited, and sEMG data of seven daily gestures were recorded. A modified fuzzy granularized logistic regression (FG_LogR) algorithm is proposed for cross-individual gesture classification.Main results.The results show that the average classification accuracy of the four features based on the FG_LogR algorithm is 79.7%, 83.6%, 79.0%, and 86.1%, while the classification accuracy based on the logistic regression algorithm is 76.2%, 79.5%, 71.1%, and 81.3%, the overall accuracy improved ranging from 3.5% to 7.9%. The performance of the FG_LogR algorithm is also superior to the other five classic algorithms, and the average prediction accuracy has increased by more than 5%.Conclusion. The proposed FG_LogR algorithm improves the accuracy of cross-individual gesture recognition by fuzzy and granulating the features, and has the potential for clinical application.Significance. The proposed algorithm in this study is expected to be combined with other feature optimization methods to achieve more precise and intelligent prosthetic control and solve the problems of poor gesture recognition and high abandonment rate of prosthetic systems.
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Gestos , Qualidade de Vida , Adulto , Humanos , Eletromiografia/métodos , Modelos Logísticos , Algoritmos , MãosRESUMO
Markerless pose estimation based on computer vision provides a simpler and cheaper alternative to human motion capture, with great potential for clinical diagnosis and remote rehabilitation assessment. Currently, the markerless 3D pose estimation is mainly based on multi-view technology, while the more promising single-view technology has defects such as low accuracy and reliability, which seriously limits clinical application. This study proposes a high-resolution graph convolutional multilayer perception (HGcnMLP) human 3D pose estimation framework for smartphone monocular videos and estimates 15 healthy adults and 12 patients with musculoskeletal disorders (sarcopenia and osteoarthritis) gait spatiotemporal, knee angle, and center-of-mass (COM) velocity parameters, etc., and compared with the VICON gold standard system. The results show that most of the calculated parameters have excellent reliability (VICON, ICC (2, k): 0.853-0.982; Phone, ICC (2, k): 0.839-0.975) and validity (Pearson r: 0.808-0.978, p<0.05). In addition, the proposed system can better evaluate human gait balance ability, and the K-means++ clustering algorithm can successfully distinguish patients into different recovery level groups. This study verifies the potential of a single smartphone video for 3D human pose estimation for rehabilitation auxiliary diagnosis and balance level recognition, and is an effective attempt at the clinical application of emerging computer vision technology. In the future, it is hoped that the corresponding smartphone program will be developed to provide a low-cost, effective, and simple new tool for remote monitoring and rehabilitation assessment of patients.
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Quantifying kinematic gait for elderly people is a key factor for consideration in evaluating their overall health. However, gait analysis is often performed in the laboratory using optical sensors combined with reflective markers, which may delay the detection of health problems. This study aims to develop a 3D markerless pose estimation system using OpenPose and 3DPoseNet algorithms. Moreover, 30 participants performed a walking task. Sample entropy was adopted to study dynamic signal irregularity degree for gait parameters. Paired-sample t-test and intra-class correlation coefficients were used to assess validity and reliability. Furthermore, the agreement between the data obtained by markerless and marker-based measurements was assessed by Bland-Altman analysis. ICC (C, 1) indicated the test-retest reliability within systems was in almost complete agreement. There were no significant differences between the sample entropy of knee angle and joint angles of the sagittal plane by the comparisons of joint angle results extracted from different systems (p > 0.05). ICC (A, 1) indicated the validity was substantial. This is supported by the Bland-Altman plot of the joint angles at maximum flexion. Optical motion capture and single-camera sensors were collected simultaneously, making it feasible to capture stride-to-stride variability. In addition, the sample entropy of angles was close to the ground_truth in the sagittal plane, indicating that our video analysis could be used as a quantitative assessment of gait, making outdoor applications feasible.
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Haemoglobin A1c (HbA1c) is a marker of glycaemic control in type 2 diabetes mellitus (T2DM). Increased waist circumference (WC) is known to be associated with T2DM. Therefore, we investigated the relationship of WC with HbA1c and explored its optimal cutoff for identifying prediabetes and diabetes risk. This study included 2339 participants between 18 and 84 years of age [mean (SD) age, 43.5 (11.9) years] with valid data on WC, HbA1c and related variables in the Shenzhen-Hong Kong United Network on Cardiovascular Disease study. Participants on anti-diabetic medications were excluded. Multiple linear regression was used to investigate the relationship between HbA1c and WC. Cutoff values of WC indicating an HbA1c level of 5.7% and 6.5% were also assessed using optimal binning. There was a significant linear relationship between WC and HbA1c in the overall population (B = 0.261, P < 0.001), men (B = 0.206, P < 0.001) and women (B = 0.311, P < 0.001). After adjustment for smoking, alcohol consumption, physical activity, hypertension, hypercholesterolaemia and age, the association remained significant in the overall population (B = 0.201, P < 0.001), men (B = 0.186, P < 0.001) and women (B = 0.182, P < 0.001). The optimal cutoff values of WC indicating an HbA1c level of 5.7% and 6.5% was 83 cm (entropy = 0.943) and 85 cm (entropy = 0.365) in men, and 78 cm (entropy = 0.922) and 86 cm (entropy = 0.256) in women. The linear relationship between WC and HbA1c in this study suggests that addressing central obesity issue is beneficial to people with T2DM or at risk of T2DM. WC cutoff values of 85 cm for men and 86 cm for women are appropriate for recommendation to undergo diabetes screening.
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Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Adulto , Índice de Massa Corporal , Criança , China/epidemiologia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Hemoglobinas Glicadas , Humanos , Masculino , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/epidemiologia , Fatores de Risco , Circunferência da CinturaRESUMO
Knee osteoarthritis is a degenerative disease, which greatly affects the daily life of patients. Total knee replacement (TKR) is the most common method to treat knee joint disorders and relieve knee pain. Postoperative rehabilitation exercise is the key to restore knee joint function. However, there is a lack of a portable equipment for monitoring knee joint activity and a systematic assessment scheme. We have developed a portable rehabilitation monitoring and evaluation system based on the wearable inertial unit to estimate the knee range of motion (ROM). Ten TKR patients and ten healthy adults are recruited for the experiment, then the system performance is verified by professional rehabilitation equipment Baltimore Therapeutic Equipment (BTE) Primus RS. The average absolute difference between the knee ROM and BTE Primus RS of healthy subjects and patients ranges from 0.16° to 4.94°. In addition, the knee ROM of flexion-extension and gait activity between healthy subjects and patients showed significant differences. The proposed system is reliable and effective in monitoring and evaluating the rehabilitation progress of patients. The system proposed in this work is expected to be used for long-term effective supervision of patients in clinical and dwelling environments.
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Wearable hip-protection airbags can effectively protect hip joints when elderly people fall. This has been studied all over the world, but similar products need to use special gas cylinders and replacement of new gas cylinders needs to return to the factory; The team previously designed a mechanical puncture protection system based on standard gas cylinders and standard threaded interfaces, but the airbag still has shortcomings such as the small protective area caused by a single gas cylinder. To solve the above problems, a set of wearable hip automatic protection systems based on micromechanical double gas cylinder rapid puncture (MDGCRP) is now designed. Through a large number of experiments, it was found that the response time of MDGCRP was 92ms and the execution time was 177.5ms. Compared with the single gas cylinder approach, the airbag provides greater protection to the hip while the filling time and module weight remain essentially unchanged. The system is triggered by physical and mechanical methods. Compared with chemical blasting or hot-melt methods, the system has the characteristics of low cost and consumables that can be safely and easily replaced by themselves.
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Air Bags , Biônica , Acidentes por Quedas/prevenção & controle , Idoso , Humanos , PunçõesRESUMO
Enhance human walking and running is much more difficult compared to build a machine to help someone with disability. Unpowered ankle-foot exoskeletons are the current development trend due to their lightweight, wearable, and energy-free features, but the huge recognition and energy control system still affects their practicability. To refine the recognition and control system, we designed an unpowered soft ankle-foot exoskeleton with a purely mechanical self-adaptiveness clutch, which can realize the collection and release of energy according to different gait stage. Through switching and closing of this clutch, energy is collected when the ankle is doing negative work and released when the ankle is doing positive work. Results shows the unpowered ankle-foot exoskeleton at the stiffness of 12000 N/m could relieve muscles' load, with reduction of force by 52.3 % and 5.2%, and of power by 44.2% and 7.0%, respectively for soleus and gastrocnemius in simulation.Clinical Relevance-The proposed Unpowered Ankle-Foot Exoskeleton can both reduce muscle forces and powers. Hence, it can be used to assist walking of the elderly, others with neurocognitive disorders or leg diseases.
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Exoesqueleto Energizado , Idoso , Tornozelo , Articulação do Tornozelo , Marcha , Humanos , CaminhadaRESUMO
3D Bioprinting is expected to become a strong tool for regenerative medicine, but satisfactory bioinks for the printing of constructs containing living cells are lacking due to the rigorous requirement of high printability and biocompatibility, which are often contradictory. Here, we have reported the development of a novel hybrid bioink by combining rigid gellan gum (GG), flexible sodium alginate (SA), and a bioactive substance thixotropic magnesium phosphate-based gel (TMP-BG). The ratio of these components was first optimized to obtain satisfactory gelating, mechanical, rheological, and printing properties. The formulated hybrid GG-SA/TMP-BG bioink had a good printability due to the shear-thinning and its multiple cross-linking by Mg2+ and Ca2+. The tunable mechanical performance of the hybrid bioink could simulate various extracellular matrices of the different tissues and support integrity of 3D printing constructs. Moreover, the hybrid bioink induced apatite deposition during immersion in simulated body fluids, and also promoted cell proliferation in vitro. MG-63 osteosarcoma cells were dispersed in the bioink and printed into 3D constructs. The cells exhibited good cell survival due to the shear-thinning property of the bioink and the ion concentration used for cross-linking. The proliferation rate of the cells also significantly exceeded those in non-printed samples. Confocal microscopy revealed a homogeneous distribution of cells in the printed constructs, and survival for more than 7 d. In vivo animal experiments showed that the hybrid bioink without cells could induce osteochondral repair. Therefore, this hybrid bioink has good printability, biocompatibility, mechanical support, and bioactivity, which is expected to have promising applications in 3D bioprinting.
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Alginatos/química , Bioimpressão , Tinta , Compostos de Magnésio/química , Fosfatos/química , Polissacarídeos Bacterianos/química , Impressão Tridimensional , Células Cultivadas , Géis/química , Humanos , Estrutura Molecular , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
In the original publication of the article the affiliation of Kamen Ivanov was inaccurate. The correct affiliation of Kamen Ivanov is given below.
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BACKGROUND: Familial adenomatous polyposis (FAP) is an autosomal dominantly inherited disease which primarily manifested with developing adenomas or polyps in colon or rectum. It is caused by the germline mutations in adenomatous polyposis coli (APC) gene. Patients with FAP are usually manifested with "hundreds or even thousands" adenomas or polyps in colon or rectum. However, without proper clinical diagnosis and timely surgical interventions, colorectal adenomas, or polyps gradually increase in size and in numbers which finally leads to colorectal cancer (CRC) at the mean age of 36 years of the patient. METHODS: In this study, we identified a family with FAP. In this family, FAP has been diagnosed clinically based on symptoms, medical test reports, and positive family history for three generations. In order to unveil the molecular genetic consequences underlying the disease phenotype, we performed next-generation sequencing with a customized and designed panel of genes reported to be associated with hereditary CRC. The variant identified by next-generation sequencing has been validated by Sanger sequencing. RESULTS: A heterozygous novel insertion [c.3992_3993insA; p.Thr1332Asnfs*10] in exon 16 of APC gene has been identified. This novel insertion is cosegregated well with the FAP phenotype among all the affected members of this family. This mutation causes a frameshift by the formation of a premature stop codon which finally results in the formation of a truncated APC protein of 1,342 amino acids instead of the wild type APC protein of 2,843 amino acids. Hence, this is a loss-of-function mutation. This mutation was not found in unaffected family members or in normal control individuals. CONCLUSION: Our present study emphasizes the importance of a novel approach of the gene panel-based high-throughput sequencing technology for easy and rapid screening for patients with FAP or CRC which will help the clinician for follow-up and management.
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Proteína da Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/genética , Mutação em Linhagem Germinativa , Polimorfismo de Nucleotídeo Único , Polipose Adenomatosa do Colo/patologia , Adulto , Feminino , Testes Genéticos/métodos , Humanos , Mutação com Perda de Função , Masculino , Pessoa de Meia-Idade , Linhagem , Análise de Sequência de DNA/métodosRESUMO
Accidental fall can cause physical injury, fracture and other health complication, especially for elderly people living alone. Aimed to provide timely assistance after the occurrence of falling down, a pre-fall alarm system was proposed. In order to test the reliability of pre-fall alarm system, eighteen subjects who worn this device on the waist were required to participate in a series of experiments. The acceleration and angular velocity time series extracted from human motion processes were used to described human motion features. HMM-based SVM classifier was used to determine the maximum separation boundary between fall and Activities of Daily Living (ADLs). The fall detection results showed 94.91% accuracy, 97.22% Sensitivity and 93.75% Specificity. The proposed device can accurately recognize fall event, achieve additional functions, and have advantages of small size and low power consumption. Based on the findings, this pre-impact fall alarm system with detection algorithm could potentially be useful for monitoring the state of physical function in elderly population.
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Acidentes por Quedas , Sistemas Microeletromecânicos , Atividades Cotidianas , Algoritmos , Humanos , Monitorização Ambulatorial , Reprodutibilidade dos Testes , Máquina de Vetores de SuporteRESUMO
This paper presents a smartphone application which has realized action recognition and fall detection. The application identifies the holding pattern of smartphone by the data of light sensor, distance sensor and accelerometer sensor, which reduce the impact of recognition resulting from the smartphone's different positions. And then the application uses data collected from the acceleration sensor, the direction angle sensor and the gyro sensor to distinguish fall from daily actions. The results of human motion recognition are uploaded to the server. For the purpose of real time, the network stability of the application is improved by the method of multi-layer detection based on heartbeat packet. Experiments prove that the way of improving network stability can reduce the rate of losing packet. The accuracy of action recognition achieves more than 90%.
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Acidentes por Quedas , Smartphone , Aceleração , Atividades Cotidianas , Humanos , Movimento (Física)RESUMO
In contrast to traditional drug administration, targeted drug delivery can prolong, localize, target and have a protected drug interaction with the diseased tissue. Drug delivery carriers, such as polymeric micelles, liposomes, dendrimers, nanotubes, and so on, are hard to scale-up, costly, and have short shelf life. Here we show the novel fabrication and characterization of photopatternable magnetic hollow microrobots that can potentially be utilized in microfluidics and drug delivery applications. These magnetic hollowbots can be fabricated using standard ultraviolet (UV) lithography with low cost and easily accessible equipment, which results in them being easy to scale up, and inexpensive to fabricate. Contact-free actuation of freestanding magnetic hollowbots were demonstrated by using an applied 900 G external magnetic field to achieve the movement control in an aqueous environment. According to the movement clip, the average speed of the magnetic hollowbots was estimated to be 1.9 mm/s.
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The emergence of 3D bioprinting is expected to solve the present puzzle in the field of regenerative medicine. However, the appropriate bioink was lacking due to the rigorous requirement of high printability and biocompatibility, which was often contradictory. In this study, a novel thixotropic magnesium phosphate-based gel (TMP-BG) was prepared and its application in 3D printing was explored. The stable gel could be synthesized by adjusting the ratio of ternary reactants (NaOH, Mg(OH)2, and H3PO4). Moreover, the structure, morphology, particle size and composition of TMP-BG were characterized. Furthermore, the rheological and thixotropic behaviors and degradation of TMP-BG were investigated. The printability of TMP-BG was tested by using the extrusion-based 3D printer. The biocompatibility of TMP-BG was evaluated in vitro. The composition of TMP-BG was MgNa3H(PO4)2, which was of nanometer and sub-micro scale and easily formed a complex three-dimensional porous structure. Rheological results showed that the gel had notable shear thinning behavior and good thixotropy, which could provide the TMP-BG with injectability and formability simultaneously. In addition, the thixotropic mechanisms of TMP-BG were speculated to be a model of "house of cards". Finally, TMP-BG could be printed into large-sized and different complex three-dimensional structures. Results of the MG-63 cell viability and cell proliferation confirmed the biocompatibility of TMG-BG. The present newly developed TMP-BG has the potential to be used as 3D printing bioink involving living cells for future applications in regenerative medicine.
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Familial adenomatous polyposis (FAP) is an autosomal dominant precancerous condition which is associated with germline mutations of the APC gene. Clinically, FAP is characterized by the development of multiple colorectal adenomas or polyps which finally result in colorectal cancer by the 40 years age of the patient, if no surgical interventions have been undertaken. In this study, we present a clinical molecular study of a four generation Chinese family with FAP. Diagnosis of FAP was made on the basis of clinical manifestations, family history and medical (colonoscopy and histopathology) records. Genetic screening of the proband and all affected family members were performed by targeted next-generation sequencing and confirmatory Sanger sequencing. Targeted next generation sequencing identified a germline novel heterozygous single nucleotide deletion [c.3418delC; p.Pro1140Leufs*25] in exon18 of APC gene, which segregated with the FAP phenotypes in the proband and in all the affected family members whereas absent in unaffected family members as well as in normal healthy controls of same ethnic origin. Our present study expands the mutational spectrum of APC gene and provides evidence to understand the function of APC gene in FAP.