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In this paper, artificial intelligence (AI) technology is applied to the electromagnetic imaging of anisotropic objects. Advances in magnetic anomaly sensing systems and electromagnetic imaging use electromagnetic principles to detect and characterize subsurface or hidden objects. We use measured multifrequency scattered fields to calculate the initial dielectric constant distribution of anisotropic objects through the backpropagation scheme (BPS). Later, the estimated multifrequency permittivity distribution is input to a convolutional neural network (CNN) for the adaptive moment estimation (ADAM) method to reconstruct a more accurate image. In the meantime, we also improve the definition of loss function in the CNN. Numerical results show that the improved loss function unifying the structural similarity index measure (SSIM) and root mean square error (RMSE) can effectively enhance image quality. In our simulation environment, noise interference is considered for both TE (transverse electric) and TM (transverse magnetic) waves to reconstruct anisotropic scatterers. Lastly, we conclude that multifrequency reconstructions are more stable and precise than single-frequency reconstructions.
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The investigation of the effects of electrical and mechanical stimulations on chondrogenesis in tissue engineering scaffolds is essential for realizing successful cartilage repair and regeneration. The aim of articular cartilage tissue engineering is to enhance the function of damaged or diseased articular cartilage, which has limited regenerative capacity. Studies have shown that electrical stimulation (ES) promotes mesenchymal stem cell (MSC) chondrogenesis, while mechanical stimulation (MS) enhances the chondrogenic differentiation capacity of MSCs. Therefore, understanding the impact of these stimuli on chondrogenesis is crucial for researchers to develop more effective tissue engineering strategies for cartilage repair and regeneration. This study focuses on the preparation of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) conductive polymer (CP) scaffolds using the freeze-drying method. The scaffolds were fabricated with varying concentrations (0, 1, 3, and 10 wt %) of (3-glycidyloxypropyl) trimethoxysilane (GOPS) as a crosslinker and an additive to tailor the scaffold properties. To gain a comprehensive understanding of the material characteristics and the phase aggregation phenomenon of PEDOT:PSS scaffolds, the researchers performed theoretical calculations of solubility parameters and surface energies of PSS, PSS-GOPS, and PEDOT polymers, as well as conducted material analyses. Additionally, the study investigated the potential of promoting chondrogenic differentiation of human adipose stem cells by applying external ES or MS on a PEDOT:PSS CP scaffold. Compared to the group without stimulation, the group that underwent stimulation exhibited significantly up-regulated expression levels of chondrogenic characteristic genes, such as SOX9 and COL2A1. Moreover, the immunofluorescence staining images exhibited a more vigorous fluorescence intensity of SOX9 and COL II proteins that was consistent with the trend of the gene expression results. In the MS experiment, the strain excitation exerted on the scaffold was simulated and transformed into stress. The simulated stress response showed that the peak gradually decreased with time and approached a constant value, with the negative value of stress representing the generation of tensile stress. This stress response quantification could aid researchers in determining specific MS conditions for various materials in tissue engineering, and the applied stress conditions could be further optimized. Overall, these findings are significant contributions to future research on cartilage repair and biophysical ES/MS in tissue engineering.
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Condrogénesis , Andamios del Tejido , Humanos , Condrogénesis/fisiología , Ingeniería de Tejidos/métodos , Polímeros/farmacología , Células Madre , Diferenciación CelularRESUMEN
OBJECTIVES: To explore the subacromial motion metrics in patients with and without subacromial impingement syndrome (SIS) and to investigate whether the abnormality was associated with rotator cuff pathologies. DESIGN: This cross-sectional observational study used dynamic quantitative ultrasonography imaging for shoulder joint assessment. SETTING: Outpatient rehabilitation clinic. PARTICIPANTS: Individuals with SIS on at least 1 shoulder (n=32) and asymptomatic controls (n=32) (N=64). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Frame-by-frame, the humeral greater tuberosity against the lateral edge of the acromion was traced to obtain the minimal vertical acromiohumeral distance (AHD). The rotation angle and radius of the humerus were computed using the least-squares curve fitting method. RESULTS: Approximately two-thirds of the shoulders with SIS did not have any sonographically identifiable rotator cuff pathologies. There was a consistent trend of nonsignificantly increased humeral rotation angles in painful shoulders. The generalized estimating equation demonstrated that the decreased minimal vertical AHD was associated with painful subacromial impingement (ß coefficient: -0.123cm, 95% confidence interval [CI], -0.199 to -0.047). The area under the curve for the minimal vertical AHD to discriminate painful or impinged shoulders ranged from 0.624-0.676. The increased rotation angle (ß coefficient: 10.516°; 95% CI, 3.103-17.929) and decreased rotation radius (ß coefficient: -2.903cm; 95% CI, -5.693 to -0.111) were shown to be significantly related to the presence of supraspinatus tendinopathy. CONCLUSIONS: Shoulders with SIS were characterized by a decreased minimal vertical AHD during dynamic examination. Abnormal subacromial metrics can develop in patients with mild (or no) rotator cuff pathologies. More prospective cohort studies are warranted to investigate the changes in subacromial motion metrics in populations at risk for painful or impinged shoulders.
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Síndrome de Abducción Dolorosa del Hombro , Articulación del Hombro , Humanos , Síndrome de Abducción Dolorosa del Hombro/diagnóstico por imagen , Estudios Transversales , Estudios Prospectivos , Hombro , Dolor , Ultrasonografía , Rango del Movimiento ArticularRESUMEN
In ideal circumstances, a fractured bone can heal properly by itself or with the aid of clinical interventions. However, around 5% to 10% of bone fractures fail to heal properly within the expected time even with the aid of clinical interventions, resulting in nonunions. Platelet gel is a blood-derived biomaterial used in regenerative medicine aiming to promote wound healing and regeneration of damaged tissues. The purpose of this paper is to review relevant articles in an attempt to explore the current consensus on the treatment effect of platelet gel on reconstructing bone defects and nonunions, hoping to provide a valuable reference for clinicians to make treatment decisions in clinical practice. Based on the present review, most of the studies applied the combination of platelet gel and bone graft to reconstruct bone defects and nonunions, and most of the results were positive, suggesting that this treatment strategy could promote successful reconstruction of bone defects and nonunions. Only two studies tried to apply platelet gel alone to reconstruct bone defects and nonunions, therefore a convincing conclusion could not be made yet regarding the treatment effect of platelet gel alone on reconstructing bone defects and nonunions. Only one study applied platelet gel combined with extracorporeal shock wave therapy to reconstruct nonunions, and the results were positive; the hypothetical mechanism of this treatment strategy is reasonable and sound, and more future clinical studies are encouraged to further justify the effectiveness of this promising treatment strategy. In conclusion, the application of platelet gel could be a promising and useful treatment method for reconstructing bone defects and nonunions, and more future clinical studies are encouraged to further investigate the effectiveness of this promising treatment method.
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Fracturas Óseas , Fracturas no Consolidadas , Materiales Biocompatibles , Trasplante Óseo/métodos , Curación de Fractura , Fracturas Óseas/terapia , Fracturas no Consolidadas/cirugía , HumanosRESUMEN
PURPOSE: Marin-Amat syndrome is an acquired facial synkinesis manifesting as involuntary eyelid closure on jaw movement. The authors investigate the clinical features, especially the quantitative changes in eyelid parameters of patients with Marin-Amat syndrome. METHODS: Patients with Marin-Amat syndrome between 2015 and 2017 in a medical center were collected. Clinical features and the change of eyelid parameters, including margin reflex distance 1 (MRD-1), margin reflex distance 2 (MRD-2), and palpebral fissure height, were evaluated. RESULTS: There were 5 men and 3 women with a mean age of 76 years. All had a history of facial palsy. The mean time to onset of Marin-Amat syndrome was 4.4 years after facial palsy. Seven patients (87.5%) developed subsequent ipsilateral facial spasm after facial palsy. Most patient complaints were ptosis (62.5%) and ptosis on eating (37.5%). The mean palpebral fissure height of involved eyes decreased from 5.88 to 2 mm on jaw opening (p = 0.011), which resulted from decrease in MRD-1 (from 2.06 to 0.06 mm, p = 0.012) and MRD-2 (from 3.81 to 1.94 mm; p = 0.012). Botulinum toxin A (Botox) injection into the periorbital orbicularis muscle in 6 patients significantly relieved the change of palpebral fissure height on jaw opening compared with that before injection (9.9% vs. 68.6 %, p = 0.027). CONCLUSIONS: Most patients with Marin-Amat syndrome present with ptosis and might be overlooked or underestimated. The reduction in palpebral fissure height in our patients with Marin-Amat syndrome was due to involuntary orbicularis oculi muscle contraction, resulting in decrease of both the MRD-1 and MRD-2 on jaw opening.
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Blefaroplastia , Blefaroptosis , Parálisis Facial , Anciano , Blefaroptosis/diagnóstico , Blefaroptosis/etiología , Blefaroptosis/cirugía , Párpados , Femenino , Humanos , Masculino , SíndromeRESUMEN
BACKGROUND/PURPOSE: To compare shear modulus of heel pad microchamber and macrochamber layers between young and elderly people using shear wave ultrasound elastography (SWUE), with the intent to clarify age-related changes. METHODS: This single-center prospective cross-sectional study was conducted between March, 2014 and March, 2016. Shear modulus of entire heel pad (Gentire), macrochamber layer (Gmac), and microchamber layer (Gmic) were measured with SWUE. RESULTS: Elderly participants (15 men, 15 women; age = 66.9 ± 6.2 years) had significantly higher Gmic (103.8 ± 20.7 vs. 60.1 ± 9.8 kPa; p < 0.001) and Gentire (39.4 ± 10.5 vs. 34.1 ± 5.4 kPa; p = 0.005), but a significantly lower Gmac (21.7 ± 7.5 vs. 27.9 ± 4.9 kPa; p < 0.001) compared with those of young participants (15 men, 15 women; age = 26.4 ± 2.9 years). Positive correlations were observed between age and Gmic (r = 0.79, p < 0.001) and between age and Gentire (r = 0.28, p = 0.03), and negative correlation between age and Gmac (r = -0.46, p = 0.001). CONCLUSION: SWUE revealed that the heel pad macrochamber layer was slightly softer but the microchamber layer was exaggeratedly stiffer, making the entire heel pad stiffer in the elderly group than in the younger group, implying age-related compensation in heel pad layers to retain foot function.
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Diagnóstico por Imagen de Elasticidad , Talón/diagnóstico por imagen , Talón/fisiología , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
This study compared two nonlinear distortion compensation techniques, SSII cancellation (in the frequency domain) and Volterra filtering (in the time domain), in a >50-Gbps/λ OFDM-IMDD LR-PON. Experiment results for SNR, BER, and data rate (based on a bit-loading algorithm) revealed that the performance of frequency-domain SSII cancellation is unaffected by power fading; however, it depends heavily on the precision of the mathematical model. Conversely, although time-domain Volterra filtering is affected by the faded waveform, adaptive-weighting provides flexibility in dealing with mixed nonlinear distortion, particularly that associated with the interplay between fiber dispersion and fiber nonlinearity. 4-channel WDM-OFDM and 3rd-order Volterra filtering were used to demonstrate the feasibility of the proposed scheme in a 200-Gbps IMDD system. Based on 10-GHz EAM and PIN, we achieved 200-Gbps transmission over a distance of 60 km with a loss budget of >30 dB, while providing support for 128 ONUs at >1.6 Gbps/ONU without the need for an inline amplifier or pre-amplifier.
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BACKGROUND: Angiomyolipoma is a benign mesenchymal tumor composed of variable amounts of smooth muscle, adipose tissue and thick-walled blood vessels, and usually named PEComas (perivascular epithelioid cell tumors). PEComas share overlapping histopathological features with epithelioid cells along a perivascular distribution and characteristic immunohistochemistry with coexpression of myoid and melanocytic markers (HMB-45 /or Melan-A). We report the first case of primary orbital angiomyolipoma with negative melanocytic marker. CASE PRESENTATION: An 80-year-old Asian woman had a 2-year history of progressive swelling in the left upper eyelid. External examination revealed 3 cm of relative proptosis of the left eye and a palpable mass in the left superonasal orbit. Computed tomographic scan demonstrated a circumscribed, heterogeneous orbital mass. Excision biopsy was done and the histological finding demonstrated the orbital mass was composed of mature adipocytes, intermingled with spindle or oval-shaped cells, and accompanied by thick-walled blood vessels. Immunohistochemically, tumor cells were positive for CD34 and HHF-35, but negative for cytokeratin, HMB-45 and Melan-A. The diagnosis of angiomyolipoma was made. No recurrence was noted at 2-year follow-up. CONCLUSION: In our case, the HMB-45 negativity may be explained by the rarity of the epithelioid cells, and the HMB-45 positivity is often weaker or absent in spindle cells. Angiomyolipoma, although rare, should be added to the differential diagnosis of space-occupying orbital lesion.
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Angiomiolipoma/metabolismo , Biomarcadores de Tumor/metabolismo , Antígenos Específicos del Melanoma/metabolismo , Neoplasias Orbitales/metabolismo , Anciano de 80 o más Años , Angiomiolipoma/diagnóstico por imagen , Angiomiolipoma/patología , Antígenos CD34/metabolismo , Biopsia , Humanos , Inmunohistoquímica , Antígeno MART-1/metabolismo , Neoplasias Orbitales/diagnóstico por imagen , Neoplasias Orbitales/patología , Tomografía Computarizada por Rayos X , Antígeno gp100 del MelanomaRESUMEN
A two-way fiber-wireless convergence system based on a two-stage injection-locked 1.55-µm vertical-cavity surface-emitting lasers (VCSELs) transmitter and an optical interleaver (IL) to deliver intensity-modulated and phase-remodulated millimeter-wave (MMW) data signals over a 40-km single-mode fiber (SMF) and a 5-m radio frequency (RF) wireless transport is proposed and experimentally demonstrated. Bit error rate (BER) and eye diagram perform brilliantly through a serious investigation in systems. Such a two-way fiber-wireless convergence system is a promising option, it reveals a prominent one to present its advancement in integration of distribute fiber and in-house network.
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A full-duplex CATV/wireless-over-fiber lightwave transmission system consisting of one broadband light source (BLS), two optical interleavers (ILs), one intensity modulator, and one phase modulator is proposed and experimentally demonstrated. The downstream light is optically promoted from 10Gbps/25GHz microwave (MW) data signal to 10Gbps/100GHz and 10Gbps/50GHz millimeter-wave (MMW) data signals in fiber-wireless convergence, and intensity-modulated with 50-550 MHz CATV signal. For up-link transmission, the downstream light is phase-remodulated with 10Gbps/25GHz MW data signal in fiber-wireless convergence. Over a 40-km single-mode fiber (SMF) and a 10-m radio frequency (RF) wireless transport, bit error rate (BER), carrier-to-noise ratio (CNR), composite second-order (CSO), and composite triple-beat (CTB) are observed to perform well in such full-duplex CATV/wireless-over-fiber lightwave transmission systems. This full-duplex 100-GHz/50-GHz/25-GHz/550-MHz lightwave transmission system is an attractive alternative. This transmission system not only presents its advancement in the integration of fiber backbone and CATV/wireless feeder networks, but also it provides the advantages of a communication channel for higher data rates and bandwidth.
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A hybrid cable television (CATV)/microwave (MW)/millimeter-wave (MMW) wavelength-division-multiplexing (WDM) light wave transmission system based on injection-locked Fabry-Perot laser diodes (FP LDs) is proposed and demonstrated. Different from conventional hybrid WDM light wave transmission systems, which need wavelength-selected distributed feedback laser diodes to support various services, the proposed systems employ injection-locked FP LDs to provide multiple applications. Over a 40 km single-mode fiber transport, impressive performances of carrier-to-noise ratio/composite second-order/composite triple-beat/bit error rate are obtained for 550 MHz CATV/20 GHz MW/40 GHz MMW/60 GHz MMW signal transmissions. Such a hybrid WDM light wave transmission system would be attractive for fiber links to provide broadband integrated services.
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In this paper a high-sensitivity low-coherence heterodyne interferometric system consisting of two polarizing Michelson interferometers arranged in tandem is presented. A compact frequency-domain optical delay line was placed in the first interferometer to produce a 4.4 kHz frequency shift for broadband near-infrared light. The frequency shift was wavelength independent because the scanning delay line had a zero-group-delay configuration. The fringe amplitude and phase of a low-coherence interference signal were detected using a lock-in amplifier. The experimental results show that the signal-to-noise ratio in the proposed technique is more than 30-fold higher than that of conventional low-coherence homodyne interferometry.
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In this study, we develop a clamped-clamped beam-type piezoelectric vacuum pressure sensing element. The clamped-clamped piezoelectric beam is composed of a PZT layer and a copper substrate. A pair of electrodes is set near each end. An input voltage is applied to a pair of electrodes to vibrate the piezoelectric beam, and the output voltage is measured at the other pair. Because the viscous forces on the piezoelectric beam vary at different air pressures, the vibration of the beam depends on the vacuum pressure. The developed pressure sensor can sense a wide range of pressure, from 6.5 × 10(-6) to 760 Torr. The experimental results showed that the output voltage is inversely proportional to the gas damping ratio, and thus, the vacuum pressure was estimated from the output voltage.
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Developing a tumor model with vessels has been a challenge in microfluidics. This difficulty is because cancer cells can overgrow in a co-culture system. The up-regulation of anti-angiogenic factors during the initial tumor development can hinder neovascularization. The standard method is to develop a quiescent vessel network before loading a tumor construct in an adjacent chamber, which simulates the interaction between a tumor and its surrounding vessels. Here, we present a new method that allows a vessel network and a tumor to develop simultaneously in two linked chambers. The physiological environment of these two chambers is controlled by a microfluidic resistive circuit using two symmetric long microchannels. Applying the resistive circuit, a diffusion-dominated environment with a small 2-D pressure gradient is created across the two chambers with velocity <10.9 nm s-1 and Péclet number <6.3 × 10-5. This 2-D pressure gradient creates a V-shaped velocity clamp to confine the tumor-associated angiogenic factors at pores between the two chambers, and it has two functions. At the early stage, vasculogenesis is stimulated to grow a vessel network in the vessel chamber with minimal influence from the tumor that is still developed in the adjacent chamber. At the post-tumor-development stage, the induced steep concentration gradient at pores mimics vessel-tumor interactions to stimulate angiogenesis to grow vessels toward the tumor. Applying this method, we demonstrate that vasculogenic vessels can grow first, followed by stimulating angiogenesis. Angiogenic vessels can grow into stroma tissue up to 1.3 mm long, and vessels can also grow into or wrap around a 625 µm tumor spheroid or a tumor tissue developed from a cell suspension. In summary, our study suggests that the interactions between a developing vasculature and a growing tumor must be controlled differently throughout the tissue development process, including at the early stage when vessels are still forming and at the later stage when the tumor needs to interact with the vessels.
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Técnicas Analíticas Microfluídicas , Neovascularización Patológica , Humanos , Técnicas Analíticas Microfluídicas/instrumentación , Dispositivos Laboratorio en un Chip , Línea Celular Tumoral , Células Endoteliales de la Vena Umbilical Humana , Difusión , Neoplasias/metabolismo , Neoplasias/patología , Inductores de la Angiogénesis/metabolismo , Inductores de la Angiogénesis/farmacología , Diseño de EquipoRESUMEN
Cutaneous melanoma is a lethal skin cancer variant with pronounced aggressiveness and metastatic potential. However, few targeted medications inhibit the progression of melanoma. Ganoderma lucidum, which is a type of mushroom, is widely used as a non-toxic alternative adjunct therapy for cancer patients. This study determines the effect of WSG, which is a water-soluble glucan that is derived from G. lucidum, on melanoma cells. The results show that WSG inhibits cell viability and the mobility of melanoma cells. WSG induces changes in the expression of epithelial-to-mesenchymal transition (EMT)-related markers. WSG also downregulates EMT-related transcription factors, Snail and Twist. Signal transduction assays show that WSG reduces the protein levels in transforming growth factor ß receptors (TGFßRs) and consequently inhibits the phosphorylation of intracellular signaling molecules, such as FAK, ERK1/2 and Smad2. An In vivo study shows that WSG suppresses melanoma growth in B16F10-bearing mice. To enhance transdermal drug delivery and prevent oxidation, two highly biocompatible compounds, polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP), are used to synthesize a dissolvable microneedle patch that is loaded with WSG (MN-WSG). A functional assay shows that MN-WSG has an effect that is comparable to that of WSG alone. These results show that WSG has significant potential as a therapeutic agent for melanoma treatment. MN-WSG may allow groundbreaking therapeutic approaches and offers a novel method for delivering this potent compound effectively.
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Reishi , Factores de Transcripción de la Familia Snail , Animales , Ratones , Reishi/química , Factores de Transcripción de la Familia Snail/metabolismo , Humanos , Melanoma/tratamiento farmacológico , Melanoma/patología , Melanoma/metabolismo , Línea Celular Tumoral , Proteína 1 Relacionada con Twist/metabolismo , Transición Epitelial-Mesenquimal/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ratones Endogámicos C57BL , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/metabolismo , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/patología , Melanoma Experimental/metabolismo , Movimiento Celular/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Alcohol Polivinílico/química , Polisacáridos/farmacología , Polisacáridos/química , Transducción de Señal/efectos de los fármacosRESUMEN
BACKGROUND: Acute kidney injury (AKI) is a severe complication of coronavirus disease 2019 (COVID-19) and is associated with a higher risk of mortality. Understanding the risk factors contributing to COVID-19-related AKI and mortality before vaccination is important for the initiation of preventative measures and early treatment strategies. METHODS: This study included patients aged ≥18 years diagnosed with COVID-19 through polymerase chain reaction from May 2020 to July 2021, admitted in three local hospitals in Taiwan, with an extended follow-up until June 30, 2022. A median follow-up period of 250 days was used to assess AKI development and mortality. AKI was defined according to the Kidney Disease Improving Global Outcomes criteria. Multivariate Cox regression analysis of AKI and mortality-related risk factors was performed. RESULTS: Of the 720 hospitalized patients with COVID-19, 90 (22%) developed AKI. Moreover, 80%, 10.1%, and 8.9% of the patients had stage 1, 2, and 3 AKI, respectively. Patients with stage 1-3 AKI had significantly lower survival rates than those without AKI (p = 0.0012). The mean duration of post-admission AKI occurrence was 9.50 ± 11.32 days. Older age, hypoalbuminemia, and higher D-dimer and ferritin levels were associated with COVID-19 mortality. In COVID-19 AKI, in addition to older age and high D-dimer and ferritin levels, chronic kidney disease emerged as an independent risk factor. CONCLUSION: COVID-19-related AKI develops early, exhibits a temporal association with respiratory failure, and is linked to an unfavorable prognosis. The mortality rate increased according to the AKI stage (p = 0.0012). Age; albumin, D-dimer, and ferritin levels; and the underlying chronic kidney disease status upon admission are crucial factors for predicting AKI development, which increases the mortality risk. Monitoring the renal function not only within 10 days of COVID-19 onset, but also within one month after the disease onset.
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PURPOSE: Biological tissues such as ligaments exhibit viscoelastic behaviours. Injury to the ligament may induce changes of these viscoelastic properties, and these changes could serve as biomarkers to detect the injury. In the present study, a novel instrument was developed to non-invasive quantify the viscoelastic properties of the ankle in vivo by the anterior drawer test. The purpose of the study was to investigate the reliability of the instrument and to compare the viscoelastic properties of the ankle between patients suffering from ankle sprain and controls. METHODS: Eight patients and eight controls participated in the present study. The reliability test was performed on three randomly chosen subjects. In patient and control test, both ankles of each subject were tested to evaluate the viscoelastic properties of the ankle. The viscosity index was defined for quantitatively evaluating the viscosity of the ankle. Greater viscosity index was associated with lower viscosity. Injured and uninjured ankles of patient and both ankles of controls were compared. RESULTS: The instrument exhibited excellent test-retest reliability (r > 0.9). Injured ankles exhibited significantly less viscosity than uninjured ankles, since injured ankles of patients had significantly higher viscosity index (8,148 ± 5,266) compared with uninjured ankles of patients (948 ± 617; p = 0.008) and controls (1,326 ± 613; p < 0.001). CONCLUSIONS: The study revealed that the viscoelastic properties of the ankle can serve as sensitive and useful clinical biomarkers to differentiate between injured and uninjured ankles. The method may provide a clinical examination for objectively evaluating lateral ankle ligament injuries.
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Traumatismos del Tobillo/diagnóstico , Traumatismos del Tobillo/fisiopatología , Articulación del Tobillo/fisiopatología , Adulto , Fenómenos Biomecánicos , Elasticidad/fisiología , Femenino , Humanos , Masculino , Examen Físico , Reproducibilidad de los Resultados , Viscosidad , Adulto JovenRESUMEN
Outer tropical cyclone rainbands (TCRs) are a concentrated region of heavy precipitation and hazardous weather within tropical cyclones (TCs). Outer TCRs pose considerable risk to human societies, but their origin remains unresolved. Here, we identify a total of 1029 outer TCRs at their formative stage from 95 TCs and present a large collection of radar observations in order to establish a robust foundation of the natural diversity of rainband origin. The results show the dominance of outer origin for the observed outer TCRs, in distinct contrast to theoretical modeling works of outer TCRs, which propose inner-origin scenarios. Our analysis also suggests that squall-line dynamics are a common, but not the sole, mechanism responsible for outer TCR formation. The nature of preexisting outer precipitation is found to be an important factor to influence the squall-line and non-squall-line outer TCR initiation.
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Subacromial motion metrics can be extracted from dynamic shoulder ultrasonography, which is useful for identifying abnormal motion patterns in painful shoulders. However, frame-by-frame manual labeling of anatomical landmarks in ultrasound images is time consuming. The present study aims to investigate the feasibility of a deep learning algorithm for extracting subacromial motion metrics from dynamic ultrasonography. Dynamic ultrasound imaging was retrieved by asking 17 participants to perform cyclic shoulder abduction and adduction along the scapular plane, whereby the trajectory of the humeral greater tubercle (in relation to the lateral acromion) was depicted by the deep learning algorithm. Extraction of the subacromial motion metrics was conducted using a convolutional neural network (CNN) or a self-transfer learning-based (STL)-CNN with or without an autoencoder (AE). The mean absolute error (MAE) compared with the manually-labeled data (ground truth) served as the main outcome variable. Using eight-fold cross-validation, the average MAE was proven to be significantly higher in the group using CNN than in those using STL-CNN or STL-CNN+AE for the relative difference between the greater tubercle and lateral acromion on the horizontal axis. The MAE for the localization of the two aforementioned landmarks on the vertical axis also seemed to be enlarged in those using CNN compared with those using STL-CNN. In the testing dataset, the errors in relation to the ground truth for the minimal vertical acromiohumeral distance were 0.081-0.333 cm using CNN, compared with 0.002-0.007 cm using STL-CNN. We successfully demonstrated the feasibility of a deep learning algorithm for automatic detection of the greater tubercle and lateral acromion during dynamic shoulder ultrasonography. Our framework also demonstrated the capability of capturing the minimal vertical acromiohumeral distance, which is the most important indicator of subacromial motion metrics in daily clinical practice.
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Aprendizaje Profundo , Síndrome de Abducción Dolorosa del Hombro , Articulación del Hombro , Humanos , Hombro/diagnóstico por imagen , Articulación del Hombro/diagnóstico por imagen , Síndrome de Abducción Dolorosa del Hombro/diagnóstico , Ultrasonografía/métodosRESUMEN
Background: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy for which ultrasound imaging has recently emerged as a valuable diagnostic tool. This meta-analysis aims to investigate the role of ultrasound radiomics in the diagnosis of CTS and compare it with other diagnostic approaches. Methods: We conducted a comprehensive search of electronic databases from inception to September 2023. The included studies were assessed for quality using the Quality Assessment Tool for Diagnostic Accuracy Studies. The primary outcome was the diagnostic performance of ultrasound radiomics compared to radiologist evaluation for diagnosing CTS. Results: Our meta-analysis included five observational studies comprising 840 participants. In the context of radiologist evaluation, the combined statistics for sensitivity, specificity, and diagnostic odds ratio were 0.78 (95% confidence interval (CI), 0.71 to 0.83), 0.72 (95% CI, 0.59 to 0.81), and 9 (95% CI, 5 to 15), respectively. In contrast, the ultrasound radiomics training mode yielded a combined sensitivity of 0.88 (95% CI, 0.85 to 0.91), a specificity of 0.88 (95% CI, 0.84 to 0.92), and a diagnostic odds ratio of 58 (95% CI, 38 to 87). Similarly, the ultrasound radiomics testing mode demonstrated an aggregated sensitivity of 0.85 (95% CI, 0.78 to 0.89), a specificity of 0.80 (95% CI, 0.73 to 0.85), and a diagnostic odds ratio of 22 (95% CI, 12 to 41). Conclusions: In contrast to assessments by radiologists, ultrasound radiomics exhibited superior diagnostic performance in detecting CTS. Furthermore, there was minimal variability in the diagnostic accuracy between the training and testing sets of ultrasound radiomics, highlighting its potential as a robust diagnostic tool in CTS.