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BACKGROUND: Basal cell carcinoma (BCC) is the most common skin cancer, accounting for approximately 80% of nonmelanoma skin cancer diagnoses each year. Among other factors, the staging of BCC is influenced by its measured diameter. Stage 1 BCC is defined as a lesion measuring 2 cm across or less. Of note, there have been increasing publications reporting features of "small-sized" BCCs, which can present smaller than 1 mm. However, few of these studies have characterized features of pigmented small-sized BCC. The application of in-vivo imaging such as dermoscopy and reflectance confocal microscopy (RCM) allows for the non-invasive distinction of these lesions from benign and malignant melanocytic neoplasms, thereby reducing unnecessary biopsies. METHODS: Within one year, three patients presented to Oregon Health and Science University's dermatology clinic with pigmented lesions of concern measuring less than 2 mm that were histologically confirmed as pigmented BCC. We sought to characterize the features of these lesions in a case series with the non-invasive imaging modalities of dermoscopy and RCM. RESULTS: All cases presented clinically as a small, brown, macule on the face. Each of the three cases exhibited differing features on dermoscopy. With the application of RCM, we were able to visualize characteristic BCC features, prompting removal by shave biopsy. CONCLUSION: To our knowledge, no other study has reported dermoscopic and RCM features of a cohort of pigmented BCCs 2 mm in diameter or smaller. We propose to define BCCs of this size as micro-BCCs. The variability of dermoscopic findings observed in our study, combined with the small size of these pigmented lesions, shows the utility of RCM as a non-invasive diagnostic tool for pigmented micro-BCCs.
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Carcinoma Basocelular , Neoplasias Cutâneas , Humanos , Dermoscopia/métodos , Microscopia Confocal/métodos , Carcinoma Basocelular/patologia , Neoplasias Cutâneas/patologia , Pele/patologiaRESUMO
To produce high-quality crops, not only excellent cultivation techniques but also accurate nutrient management techniques are important. In recent years, many nondestructive tools such as the chlorophyll meter "SPAD" and the leaf nitrogen meter "Agri Expert CCN" have been developed for measuring crop leaf chlorophyll and nitrogen contents. However, such devices are still relatively expensive for individual farmers. In this research, we developed a low-cost and small-size camera with built-in LEDs of several specific wavelengths for evaluating the nutrient status of fruit trees. A total of 2 camera prototypes were developed by integrating 3 independent LEDs of specific wavelengths (Camera 1: 950 nm, 660 nm and 560 nm; Camera 2: 950 nm, 660 nm and 727 nm) into the device. In addition, a simple software tool was developed to enable the camera to capture leaf images under different LED lighting conditions. Using the prototypes, we acquired images of apple leaves and investigated the possibility of using the images to estimate the leaf nutrient status indicator SPAD (chlorophyll) and CCN (nitrogen) values obtained using the above-mentioned standard tools. The results indicate that the Camera 1 prototype is superior to the Camera 2 prototype and can potentially be applied to the evaluation of nutrient status in apple leaves.
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Fabaceae , Frutas , Iluminação , Árvores , Clorofila , NitrogênioRESUMO
MOTIVATION: This paper proposes a small-sized hologram system for the 3D imaging of lesions in a clinical environment. In a general hologram system, the distance between the beam-generating device and the screen (400 mm) and the size of the screen must be increased proportionally to obtain excellent image quality. However, in a clinical environment, the beam spread distance and screen size must be reduced. This paper proposes a method for reducing the beam divergence distance and screen size for clinical applications. METHODS: To reduce the beam spread distance and screen size, a beam prism with a 45° refractive index is used to reduce the beam spread distance by 1/3. The direction of the bent light must be adjusted such that it can reach the screen accurately. However, because the reflected light may be refracted owing to the material properties of the mirror and cause loss, this problem can be solved by using a full reflection mirror. RESULTS: The beam spread distance of the designed hologram system is 200 mm. The types of lesions obtained from the 3D images of the hologram include the lung, liver, and colon. The image resolution is 300 × 145. CONCLUSION: If the proposed method is used in a clinical environment, doctors can improve their understanding of the patient quickly and efficiently; thereby, shortening the treatment time. The proposed hologram system is expected to be useful in treatment rooms, operating rooms, and educational programs in medical schools.
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Diagnóstico por Imagem , Imageamento Tridimensional , Humanos , Imageamento Tridimensional/métodos , Diagnóstico por Imagem/métodosRESUMO
PURPOSE: The purpose was to evaluate the clinical and radiological results of knotless repair with flat-braided suture in full small-sized supraspinatus tendon tears (< 1 cm). METHODS: A consecutive series of 54 patients with isolated small supraspinatus tendon tear (< 1 cm and Goutallier index < 2) was evaluated in the study. Patients underwent a knotless arthroscopic repair using flat-braided suture (2 mm wide). Minimal follow-up required was 5 years. Changes in Murley-Constant score, ASES score, strength, and pain relief were assessed. The Sugaya score was used to confirm the tendon repair on MRI. Data were analyzed in two subgroups: technique with additional U point for dog ear deformity (group 1) and technique without additional U point (group 2). The immobilization period was 3 weeks long. Passive mobilization was immediate. RESULTS: Fifty-four patients were included. Mean age was 57 ± 4 years. The average follow-up was 68 ± 10 months. Average preoperative score of Constant was 51.2 ± 8.5 and 83.1 ± 14.6 at the end of the follow-up (p < 0.001). Mean VAS went from 5.8 ± 1.8 to 1.9 ± 2.1 (p < 0.001). Average forward elevation of the shoulder went from 86.3° ± 9 preoperatively to 169.6° ± 15.9 at the end of the follow-up (p < 0.001). The strength score was significantly higher post-operatively (18.4 vs. 8.3, p < 0.001.). The ASES score was significantly improved 49.1 ± 13.1 vs. 88.6 ± 15.8, p < 0.001). The MRI assessment revealed 94% of Sugaya 1-2. No significant difference was observed between group 1 and 2 regarding all clinical outcomes. Two complex regional pain syndromes were described with a favorable evolution. Three patients presented a retear requiring an iterative arthroscopic repair. CONCLUSION: The use of a knotless arthroscopic construct with flat-braided suture for small supraspinatus repair achieved excellent structural and clinical results. This technique is fully adequate for the arthroscopic treatment of such tears, enabling early mobilization. LEVEL OF EVIDENCE: Level III.
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Artroscopia/métodos , Lesões do Manguito Rotador/cirurgia , Técnicas de Sutura , Traumatismos dos Tendões/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/diagnóstico por imagem , Ombro/diagnóstico por imagem , Ombro/fisiopatologia , Ombro/cirurgia , Dor de Ombro/epidemiologia , Traumatismos dos Tendões/diagnóstico por imagem , Tendões/cirurgia , Resultado do TratamentoRESUMO
In this paper, a displacement sensor with an electrically extremely small size and high sensitivity is proposed based on an elaborately designed metamaterial element, i.e., coupled split-ring resonators (SRRs). The sensor consists of a feeding structure with a rectangular opening loop and a sensing structure with double-layer coupled SRRs. The movable double-layer structures can be used to measure the relative displacement. The size of microwave displacement sensors can be significantly reduced due to the compact feeding and sensing structures. By adjusting the position of the split gap within the resonator, the detection directions of the displacement sensing can be further expanded accordingly (along with the x- or y-axis) without increasing its physical size. Compared with previous works, the extremely compact size of 0.05λ0 × 0.05λ0 (λ0 denotes the free-space wavelength), a high sensitivity, and a high quality factor (Q-factor) can be achieved by the proposed sensor. From the perspective of the advantages above, the proposed sensor holds promise for being applied in many high-precision industrial measurement scenarios.
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BACKGROUND: Preterm birth, small size for gestational age (SGA) and large size for gestational age (LGA) at birth are major risk factors for neonatal and long-term morbidity and mortality. It is unclear which periods of pregnancy are optimal for ultrasound screening to identify fetuses at risk of preterm birth, SGA or LGA at birth. We aimed to examine whether single or combined second and third trimester ultrasound in addition to maternal characteristics at the start of pregnancy are optimal to detect fetuses at risk for preterm birth, SGA and LGA. METHODS: In a prospective population-based cohort among 7677 pregnant women, we measured second and third trimester estimated fetal weight (EFW), and uterine artery pulsatility and umbilical artery resistance indices as placenta flow measures. Screen positive was considered as EFW or placenta flow measure < 10th or > 90th percentile. Information about maternal age, body mass index, ethnicity, parity, smoking, fetal sex and birth outcomes was available from questionnaires and medical records. Screening performance was assessed via receiver operating characteristic (ROC) curves and area under the curve (AUC) along with sensitivity at different false-positive rates. RESULTS: Maternal characteristics only and in combination with second trimester EFW had a moderate performance for screening for each adverse birth outcome. Screening performance improved by adding third trimester EFW to the maternal characteristics (AUCs for preterm birth 0.64 (95%CI 0.61 to 0.67); SGA 0.79 (95%CI 0.78 to 0.81); LGA 0.76 (95%CI 0.75; 0.78)). Adding third trimester placenta measures to this model improved only screening for risk of preterm birth (AUC 0.72 (95%CI 0.66 to 0.77) with sensitivity 37% at specificity 90%) and SGA (AUC 0.83 (95%CI 0.81 to 0.86) with sensitivity 55% at specificity 90%). Combining second and third trimester fetal and placental ultrasound did not lead to a better performance as compared to using only third trimester results. CONCLUSIONS: Combining single third trimester fetal and placental ultrasound results with maternal characteristics has the best screening performance for risks of preterm birth, SGA and LGA. As compared to second trimester screening, third trimester screening may double the detection of fetuses at risk of common adverse birth outcomes.
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Recém-Nascido Pequeno para a Idade Gestacional/fisiologia , Segundo Trimestre da Gravidez/fisiologia , Terceiro Trimestre da Gravidez/fisiologia , Nascimento Prematuro/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Adulto , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Gravidez , Cuidado Pré-Natal , Estudos Prospectivos , Adulto JovemRESUMO
BACKGROUND: In current guidelines, endoscopic ultrasound with fine-needle aspiration (EUS-FNA) is recommended in pancreatic cystic lesions (PCLs) with worrisome features (size ≥ 3 cm, mural nodule, or Wirsung dilation). OBJECTIVE: To evaluate the diagnostic ability and assess the accuracy of EUS-FNA in PCLs smaller than 3 cm. METHODS: Retrospective study of PCLs < 3 cm (2007-2016) undergoing EUS-FNA. Clinical, EUS and pancreatic cystic fluid (PCF) data were prospectively registered. Performance of EUS-FNA with PCF analysis for the detection of malignancy and accuracy in surgical cohort were analyzed. RESULTS: We evaluated 115 patients with PCLs < 3 cm who underwent EUS-FNA. 19 patients underwent surgery, 7 had malignant, 8 pre-malignant, and the remaining 4 benign lesions. Mass/mural nodule was present in 27% of the cysts, CEA level was higher than 192 ng/mL in 39.4% of patients, and only 35% of cytologic samples were informative. Nevertheless, additional FNA for PCF analysis improved the diagnostic performance of EUS imaging-AUC = 0.80 versus AUC = 60. CONCLUSION: EUS-FNA has good accuracy in PCLs < 3 cm. It confirmed malignancy even in lesions without worrisome features (nodule/mass), with two in every five resections showing high-risk/malignant lesions. EUS-FNA was also useful to diagnose benign cysts, possibly allowing surveillance to be stopped in one in every five patients.
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Cisto Pancreático , Neoplasias Pancreáticas , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Endossonografia , Humanos , Cisto Pancreático/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Estudos RetrospectivosRESUMO
Endoscopic ultrasonography (EUS)-guided ethanol injection was recently proposed for treatment of patients with small pancreatic neuroendocrine tumors (p-NET); however, tips on how to carry out safe and effective procedures are unclear. We launched a pilot study for scheduled early EUS-guided ethanol reinjection for small p-NET. Major eligibility criteria were presence of pathologically diagnosed grade (G) 1 or G2, tumor size ≤2 cm and being a poor or rejected candidate for surgery. For the treatment, we used a 25-gauge needle and pure ethanol. Contrast-enhanced computed tomography (CE-CT) was carried out on postoperative day 3, and if enhanced areas of the tumor were still apparent, an additional session was scheduled during the same hospitalization period. Primary endpoint was complete ablation rate at 1 month after treatment, and secondary endpoint was procedure-related adverse events. A total of five patients were treated. Median size of the tumor was 10 (range: 7-14) mm. Of the five patients, three underwent an additional session. Median volume of ethanol injection per session was 0.8 (range: 0.3-1.0) mL, and the total was 1.0 (0.9-1.8) mL. Complete ablation was achieved in four of the five tumors (80%) with no adverse events. During 1 year of follow up, none of the patients reported any procedure-related adverse events, and no recurrence of tumor. Scheduled early EUS-guided ethanol reinjection appears to be safe and effective for treating small p-NET (UMIN number: 000018834).
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Técnicas de Ablação , Endossonografia , Etanol/administração & dosagem , Tumores Neuroendócrinos/terapia , Neoplasias Pancreáticas/terapia , Solventes/administração & dosagem , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Projetos Piloto , Resultado do TratamentoRESUMO
Positive and negative predictive values describe the performance of a diagnostic test. There are several methods to test the equality of predictive values in paired designs. However, these methods were premised on large sample theory, and they may not be suitable for small-size clinical trials because of inflation of the type 1 error rate. In this study, we propose an exact test to control the type 1 error rate strictly for conducting a small-size clinical trial that investigates the equality of predictive values in paired designs. In addition, we execute simulation studies to evaluate the performance of the proposed exact test and existing methods in small-size clinical trials. The proposed test can calculate the exact P value, and as a result of simulations, the empirical type 1 error rate for the proposed test did not exceed the significance level regardless of the setting, and the empirical power for the proposed test is not much different from the other methods based on large-sample theory. Therefore, it is considered that the proposed exact test is useful when the type 1 error rate needs to be controlled strictly.
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Ensaios Clínicos como Assunto/métodos , Testes Diagnósticos de Rotina/métodos , Projetos de Pesquisa , Simulação por Computador , Humanos , Modelos Estatísticos , Valor Preditivo dos Testes , Tamanho da AmostraRESUMO
OBJECTIVE: This quasi-experimental study reported the results of a structured literacy intervention programme designed for secondary school students of Year 7 to Year 9 with dyslexia. Students of the intervention group (n = 116) participated in 40-week sessions of small-size, classroom-based, and split-group intervention setting with 45-min daily lesson on both Chinese and English language compared with students in the control group who received normal classroom instructions (n = 98). RESULTS: Students in the intervention group outperformed the control groups in self-regulated learning scales, which indicated that there was positive change in students' behavioural and cognitive outcomes in learning. Although students demonstrated gains in phonetic skills, posttest results in academic achievement did not exhibit significant improvement when compared with their control group peers. CONCLUSION: The findings provided some encouraging evidence of the effectiveness of intervention programme. Students that demonstrated gains in phonetic skills and improvement in behavioural and cognitive aspects required continuous intervention lessons to become a self-regulated learner, who would be self-motivated to improve methods of learning and adopt strategies for attaining academic goals. The study contributed to the literature by presenting one of the very first school-based, small-size, classroom-based, and split-group intervention programme for secondary school dyslexic students, which included teachers and students training on English and Chinese intervention content (phonological and literacy content), teaching curriculum integrated with school curriculum, and coteaching with school teachers in the mainstream classrooms, whereas most of the existing intervention programmes used pull-out approach involving the first language only.
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Dislexia/terapia , Alfabetização/psicologia , Leitura , Ensino de Recuperação/métodos , Estudantes/psicologia , Logro , Adolescente , Currículo , Dislexia/psicologia , Feminino , Hong Kong , Humanos , Idioma , Aprendizagem , Masculino , Fonética , Avaliação de Programas e Projetos de Saúde , Instituições Acadêmicas , Inquéritos e QuestionáriosRESUMO
Class IV Flextensional Transducers (FTs) are the most popular among various FTs used as low-frequency and high power underwater acoustic sources. However, an undeniable fact exists in Class IV FTs is that the resonance frequency of breathing mode regulator used is fairly raised by its longitudinal driver stacks. In this research, a conformal driving Class IV FT in which the driver stacks are kept conformal with its oval shell was proposed aiming at the limitations of conventional driving Class IV FTs described above. The device exhibits competitive Transmitting Voltage Responses (TVRs) but much lower operation frequencies with respect to conventional driving Class IV FTs, through the designs of conformal and segmentally controlled driver stacks. Geometric parameters analysis was carried out extensively by Finite Element (FE) simulations for the design optimizations and then a conformal driving Class IV FT resonating at 510 Hz (45% approximately lower than that of conventional driving Class IV FT with the same shell geometry) was finalized. Subsequently the conformal driving Class IV was fabricated and tested in the anechoic tank experimentally. Good agreements of both FE predictions and experimental results demonstrate its low-frequency and small-size acoustic performance.
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During the propagation of ultrasonic waves in structures, there is usually energy loss due to ultrasound energy diffusion and dissipation. The aim of this research is to characterize the ultrasound energy diffusion that occurs due to small-size damage on an aluminum plate using piezoceramic transducers, for the future purpose of developing a damage detection algorithm. The ultrasonic energy diffusion coefficient is related to the damage distributed in the medium. Meanwhile, the ultrasonic energy dissipation coefficient is related to the inhomogeneity of the medium. Both are usually employed to describe the characteristics of ultrasound energy diffusion. The existence of multimodes of Lamb waves in metallic plate structures results in the asynchronous energy transport of different modes. The mode of Lamb waves has a great influence on ultrasound energy diffusion as a result, and thus has to be chosen appropriately. In order to study the characteristics of ultrasound energy diffusion in metallic plate structures, an experimental setup of an aluminum plate with a through-hole, whose diameter varies from 0.6 mm to 1.2 mm, is used as the test specimen with the help of piezoceramic transducers. The experimental results of two categories of damages at different locations reveal that the existence of damage changes the energy transport between the actuator and the sensor. Also, when there is only one dominate mode of Lamb wave excited in the structure, the ultrasound energy diffusion coefficient decreases approximately linearly with the diameter of the simulated damage. Meanwhile, the ultrasonic energy dissipation coefficient increases approximately linearly with the diameter of the simulated damage. However, when two or more modes of Lamb waves are excited, due to the existence of different group velocities between the different modes, the energy transport of the different modes is asynchronous, and the ultrasonic energy diffusion is not strictly linear with the size of the damage. Therefore, it is recommended that only one dominant mode of Lamb wave should be excited during the characterization process, in order to ensure that the linear relationship between the damage size and the characteristic parameters is maintained. In addition, the findings from this paper demonstrate the potential of developing future damage detection algorithms using the linear relationships between damage size and the ultrasound energy diffusion coefficient or ultrasonic energy dissipation coefficient when a single dominant mode is excited.
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INTRODUCTION: Femoral components with inbuilt rotation require thicker flexion resection of the lateral femoral condyle and could have a potential risk of damaging the popliteus tendon, especially in the smaller Asian knees. MATERIALS AND METHODS: We prospectively evaluated 10 patients with bilateral varus osteoarthritis knee to size the cuts and their location in relation to the popliteus tendon. Two different types of implant were used on either side; one side requires resection in 3° external rotation (group A) and the other side requires a femoral component with inbuilt external rotation (group B). We observed the incidence of injury to the popliteus tendon and distance between flexion cut to its attachment over the lateral femoral condyle between both groups. RESULTS: We had popliteus tendon injury in 3 knees all from group B. Risk of damaging the popliteus tendon was found higher in group B, as the distance between flexion cut to popliteus tendon attachment was significantly low. CONCLUSION: Femoral component with inbuilt external rotation has more risk of injuring the popliteus tendon because flexion cut takes out more bone from the lateral femoral condyle.
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Artroplastia do Joelho/efeitos adversos , Prótese do Joelho/efeitos adversos , Desenho de Prótese/efeitos adversos , Traumatismos dos Tendões/etiologia , Idoso , Feminino , Fêmur/cirurgia , Humanos , Índia , Joelho/cirurgia , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Amplitude de Movimento Articular , Rotação , Tendões/cirurgiaRESUMO
Existing automatic building extraction methods are not effective in extracting buildings which are small in size and have transparent roofs. The application of large area threshold prohibits detection of small buildings and the use of ground points in generating the building mask prevents detection of transparent buildings. In addition, the existing methods use numerous parameters to extract buildings in complex environments, e.g., hilly area and high vegetation. However, the empirical tuning of large number of parameters reduces the robustness of building extraction methods. This paper proposes a novel Gradient-based Building Extraction (GBE) method to address these limitations. The proposed method transforms the Light Detection And Ranging (LiDAR) height information into intensity image without interpolation of point heights and then analyses the gradient information in the image. Generally, building roof planes have a constant height change along the slope of a roof plane whereas trees have a random height change. With such an analysis, buildings of a greater range of sizes with a transparent or opaque roof can be extracted. In addition, a local colour matching approach is introduced as a post-processing stage to eliminate trees. This stage of our proposed method does not require any manual setting and all parameters are set automatically from the data. The other post processing stages including variance, point density and shadow elimination are also applied to verify the extracted buildings, where comparatively fewer empirically set parameters are used. The performance of the proposed GBE method is evaluated on two benchmark data sets by using the object and pixel based metrics (completeness, correctness and quality). Our experimental results show the effectiveness of the proposed method in eliminating trees, extracting buildings of all sizes, and extracting buildings with and without transparent roof. When compared with current state-of-the-art building extraction methods, the proposed method outperforms the existing methods in various evaluation metrics.
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This study aimed to examine the mechanisms of cellular activation by small-size platelet microparticles (sPMP) and to present the performance of high-resolution flow cytometry for the analysis of subcellular entities from different origins. Plasma counts of sPMP were analysed in coronary artery disease patients (n = 40) and healthy controls (n = 40). The effect of sPMP and platelet debris (PD) in pathophysiologically relevant doses on platelet and monocyte activation parameters and thrombogenesis was investigated via flow cytometry and thromboelastometry. New generation flow cytometry identifies differences in size, levels and surface molecules of sPMP derived in the absence of stimulus, thrombin activation and platelet disruption. Addition of sPMP resulted in platelet degranulation and P-selectin redistribution to the membrane (P = 0·019) in a dose and time-dependent manner. Blood clotting time decreased after addition of sPMP (P = 0·005), but was not affected by PD. Blocking P-selectin (CD62P) in sPMP markedly reverted the effect on thrombus kinetics (P = 0·035). Exposure to sPMP stimulated monocyte expression of intercellular adhesion molecule-1 (P < 0·03) and decreased monocyte interleukin-6 receptor density (P < 0·01). These results implicate sPMP as a direct source of downstream platelet and monocyte activation. In pathological coronary artery disease conditions, higher levels of sPMP favour a prothrombotic state, partly through P-selectin expression.
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Plaquetas/fisiologia , Monócitos/fisiologia , Selectina-P/fisiologia , Ativação Plaquetária/fisiologia , Trombose/sangue , Análise de Variância , Coagulação Sanguínea/fisiologia , Plaquetas/metabolismo , Estudos de Casos e Controles , Doença da Artéria Coronariana/sangue , Feminino , Citometria de Fluxo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Masculino , Pessoa de Meia-Idade , Selectina-P/metabolismo , Tromboelastografia , Trombina/fisiologiaRESUMO
We have recently shown that retinoic acid induces micronucleation mainly via chromosome breakage (Alakhras et al. Cancer Lett 2011; 306: 15-26). To further study retinoic acid clastogenicity and evaluate DNA damaging potential we investigated the ability of (a) all-trans retinoic acid and its steroidal analogue EA-4 to induce DNA fragmentation by using Comet assay under alkaline unwinding and neutral condition electrophoresis, and (b) the retinoids under study to induce small (0-1 kb) DNA fragments. Two cell lines, C2C12 mouse cells and HL-60 human leukemic cells were used in this study. We found that all-trans retinoic acid and its steroidal analogue EA-4 (a) provoke DNA migration due to DNA fragmentation as it is shown by the increased values of Comet parameters, and (b) induce significantly small-size fragmented genomic DNA as indicated by the quantification of necrotic/apoptotic small DNA segments in both cell systems. A different response between the two cell lines was observed in relation to retinoid ability to increase the percentage of DNA in the tail as well as break DNA in to small fragments. Our findings confirm the ability of retinoic acid to provoke micronucleation by disrupting DNA into fragments, among which small pieces of double-stranded DNA up to 1 kb are identified.
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Antineoplásicos/farmacologia , Fragmentação do DNA/efeitos dos fármacos , Tretinoína/análogos & derivados , Tretinoína/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaio Cometa , Células HL-60 , Humanos , CamundongosRESUMO
The synthesis of high-entropy alloys (HEAs) with ultra-small particle sizes has long been a challenging task. The complex and time-consuming synthesis process hinders their practical application and widespread adoption. This study presents the novel synthesis of TiO2 nanoparticles loaded with a quinary high-entropy alloy through flame spray pyrolysis (FSP) for the first time. The extremely fast heating rate of flame combustion makes the precursor fast pyrolysis gasification, high temperature in the flame field promotes the metal vapor mixing uniformly, and the fast quenching process can reduce the particle aggregation sintering, the ultra-small particle size of HEA firmly attached to the TiO2 surface. The catalysts prepared via this gas-to-particle pathway exhibit excellent performance in CO2 hydrogenation, achieving a conversion rate of 62% at 450 °C, and maintaining their activity for over 220 h without significant particle agglomeration. This finding provides valuable insights for the future design of catalytically active materials with enhanced activity and long-term stability.
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Small-size gold nanoparticles (AuNPs) are showing large potential in various fields, such as photothermal conversion, sensing, and medicine. However, current synthesis methods generally yield lower, resulting in a high cost. Here, we report a novel uni-micelle method for the controlled synthesis of monodisperse gold nanocrystals, in which there is only one kind micelle containing aqueous solution of reductant while the dual soluble Au (III) precursor is dissolved in oil phase. Our synthesis includes the reversible phase transfer of Au (III) and "uni-micelle" synthesis, employing a Au (III)-OA complex as an oil-soluble precursor. Size-controlled monodisperse AuNPs with a size of 4-11 nm are synthesized by tuning the size of the micelles, in which oleylamine (OA) is adsorbed on the shell of micelles and enhances the rigidity of the micelles, depressing micellar coalescence. Monodisperse AuNPs can be obtained through a one-time separation process with a higher yield of 61%. This method also offers a promising way for the controlled synthesis of small-size alloy nanoparticles and semiconductor heterojunction quantum dots.
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It is a challenge to polish the interior surface of a small bent pipe with complex structures and sizes less than 0.5 mm. This is because of the fact that traditional polishing methods could destroy, block, or break the small complex structures. For a small bent pipe made of aluminum alloy produced using additive manufacturing, the defects, such as adhered powders and spatters, are easy to jam the pipe without polishing, possibly resulting in catastrophic failure for aerospace applications. To overcome this challenge, a novel water jet polisher was developed using soft polymethyl methacrylate (PMMA) abrasives. After polishing a specific area, the adhered powders on the interior surface were reduced from over 140 to 2, 3, and 6 by the soft abrasives with mesh sizes of 200, 400, and 600, respectively. The surface roughness Sa was decreased from 3.41 to 0.92 µm after polishing using PMMA abrasives with a mesh size of 200. In comparison, silica abrasives were also employed to polish the small bent pipes, leading to the bent part of pipes breaking. However, this kind of failure was absent when using soft abrasives. Computational fluid dynamics calculations elucidate that a peak erosion rate of silica abrasives for a bent pipe with a turn angle of 30° is 2.18 kg/(m2·s), which is 17 times that of soft abrasives. This is why the small bent pipe was broken using silica abrasives, whereas it remained intact when polished with soft abrasives. In addition, water jet polishing has a lower erosion rate, a relatively smooth erosion curve, and less erosion energy, leaving the bent parts intact. The developed soft abrasive water jet polisher and the findings of this study suggest new possibilities for cleaning the adhered powders and spatters and polishing the interior surface of small bent pipes with complex structures.
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BACKGROUND: Coiling of small superior cerebellar artery aneurysms (sSCAAs) is challenging. We aimed to describe anatomic considerations in the vertebral and basilar artery (VA and BA) morphology for decision making in the coiling of sSCAAs. METHODS: Eleven patients with sSCAAs (<5 mm) treated at our institution between April 2015 and February 2022 were included to show our concept of deciding access routes in the coiling of sSCAAs. The access route was decided on the basis of VA characteristics, BA curvature, and aneurysm laterality. Adequate aneurysm occlusion on angiography (Raymond-Roy grading scale I and II), good outcome (modified Rankin Score 0-2) at the last follow-up, and adverse outcomes were evaluated. RESULTS: Simple coiling (n = 2), a balloon-assisted technique (n = 3), and stent-assisted technique (n = 6) were selected. At the last follow-up (median 13.0 months), adequate aneurysm occlusion and good outcome were obtained in all 9 patients (n = 10). Adverse outcomes were not observed. When VA dominance was equal, in the straight BA, the microcatheter insertion into the ipsilateral VA to the aneurysm was favorable to form a "fulcrum" on the contralateral side and obtain microcatheter stability. When an aneurysm was on the concave aspect of the curved BA, microcatheter insertion into the ipsilateral VA was favorable. As for the convex aspect's aneurysm location, the microcatheter insertion into the contralateral VA can be favored. Further, we described the VA origin classification as it relates to ease of access from a transradial approach. CONCLUSIONS: Vertebrobasilar morphology may be important in deciding access routes in the coiling of sSCAAs.