Development, validation and reliability testing of the hospice care environment scale.

BACKGROUND: WHO stated the environment is an important factor affecting the development of hospice care. The environment is the sum of factors affecting behavior besides the individual factors. Currently, a scale to comprehensively assess the hospice environment of nurse is still lacking. This study aimed to develop an instrument to investigate the environmental factors affecting hospice care of nurses. METHODS: Literature review and a semi-structured interview were conducted to form the items pool of the Hospice Care Environment Scale. Two rounds of Delphi expert consultation were conducted by 16 experts to revise the scale dimensions and entries to form the Hospice Care Environment Scale. A psychometric evaluation was then performed among 530 oncology nurses in a large tertiary oncology hospital in Hubei Province. The 500 valid questionnaires were randomly divided into two groups in a 1:1 ratio, sample 1 (n1 = 250) for item screening and sample 2 (n2 = 250) for quality evaluation of the resulting scale. Item analysis, reliability analysis, validity analysis and acceptability analysis were performed. RESULT: The Hospice Care Environment Scale consists of two dimensions and 13 entries. The Cronbach's α coefficient of the Hospice Care Environment Scale was 0.970, and the Cronbach's α coefficient of the two dimensions were 0.952 and 0.969, respectively, with the Item-content validity index and average Scale- content validity index of the scale was both 1.000. The validation factor analysis showed the standardized path coefficients of each item were basically above 0.5, and the factor structure model was stable and suitable. The average completion time of the scale was about 3 min, which had good feasibility. CONCLUSION: The Hospice Care Environment Scale to assess the environment of hospice care services, has good content and construct validity and reliability. This scale can provide guidance to evaluate the hospice care environment.

Multi-level optical angiography for photodynamic therapy.

Blood flow imaging is widely applied in photodynamic therapy (PDT) to provide vascular morphological and statistical parameters. This approach relies on the intensity of time-domain signal differences between blood vessels and background tissues; therefore, it often ignores differences within the vasculature and cannot accommodate abundant structural information. This study proposes a multi-level optical angiography (MOA) method for PDT. It can enhance capillaries and image vessels at different levels by measuring the signal frequency shift associated with red blood cell motion. The experimental results regarding the PDT-induced chorioallantoic membrane model showed that the proposed method could not only perform multi-level angiography but also provide more accurate quantitative information regarding various vascular parameters. This MOA method has potential applications in PDT studies.

Heart rate estimation from color video sequences with high SNR.

We propose an absorption intensity heartbeat modulation-averaged shifted histogram (AIHM-ASH) method for estimating human heart rate (HR) using color videos of lip image sequences. When heartbeat occurs, AIHM is generated. Based on the AIHM, HR signals can be demodulated by computing the instantaneous HR modulation depth that presents the relative red blood cell (RBC) concentration from the green channel image of the RGB color video. In addition, the ASH algorithm further suppresses the background tissue and vein signals, and increases the signal-to-noise ratio (SNR). The experimental results for flow phantoms, chicken embryos, and human lips validated the proposed method's optimal estimation conditions and effectiveness, where the accuracy and root mean square error (RMSE) were 99.23% and 0.8 bpm, respectively. The proposed HR estimation method has significant potential to advance health monitoring and disease prevention via conventional color video cameras installed in public places.

Spatiotemporal absorption fluctuation imaging based on U-Net.

SIGNIFICANCE: Full-field optical angiography is critical for vascular disease research and clinical diagnosis. Existing methods struggle to improve the temporal and spatial resolutions simultaneously. AIM: Spatiotemporal absorption fluctuation imaging (ST-AFI) is proposed to achieve dynamic blood flow imaging with high spatial and temporal resolutions. APPROACH: ST-AFI is a dynamic optical angiography based on a low-coherence imaging system and U-Net. The system was used to acquire a series of dynamic red blood cell (RBC) signals and static background tissue signals, and U-Net is used to predict optical absorption properties and spatiotemporal fluctuation information. U-Net was generally used in two-dimensional blood flow segmentation as an image processing algorithm for biomedical imaging. In the proposed approach, the network simultaneously analyzes the spatial absorption coefficient differences and the temporal dynamic absorption fluctuation. RESULTS: The spatial resolution of ST-AFI is up to 4.33 µm, and the temporal resolution is up to 0.032 s. In vivo experiments on 2.5-day-old chicken embryos were conducted. The results demonstrate that intermittent RBCs flow in capillaries can be resolved, and the blood vessels without blood flow can be suppressed. CONCLUSIONS: Using ST-AFI to achieve convolutional neural network (CNN)-based dynamic angiography is a novel approach that may be useful for several clinical applications. Owing to their strong feature extraction ability, CNNs exhibit the potential to be expanded to other blood flow imaging methods for the prediction of the spatiotemporal optical properties with improved temporal and spatial resolutions.

Vitreous opacities in infants born full-term and preterm by handheld swept-source optical coherence tomography.

PURPOSE: To compare vitreous opacity density in infants born at term and in infants born prematurely using an investigational handheld swept-source optical coherence tomography (SS-OCT). METHODS: Infants born at term underwent imaging once between 12 and 48 hours after birth; infants born prematurely were imaged at each routine retinopathy of prematurity (ROP) examination. Three masked, trained graders analyzed images. Semiautomated methods were used to quantify vitreous opacity density, which was correlated with ROP severity based on indirect ophthalmoscopy, other SS-OCT findings, and medical comorbidities. RESULTS: Between April 2018 and June 2019, 251 SS-OCT imaging sessions were performed on 78 infants (49% female; 36% preterm, with mean birth weight of 1018 ± 338 g and gestational age of 28.6 ± 3.2 weeks). All SS-OCT sessions produced images of adequate quality. Punctate vitreous opacities were present in 25 of 28 term infants (89%) and 41 of 50 premature infants (82%). Dice coefficient and F1 scores for intergrader agreement were 0.99 ± 0.03 and 0.77 ± 0.31, respectively. Vitreous opacity density was 0.118 ± 0.187 in prematurely born infants and 0.031 ± 0.118 in infants born at term (P = 0.009). In the former, vitreous opacity density was associated with ROP zone (P = 0.044) and stage (P = 0.031), intraventricular hemorrhage (P = 0.028), subchorionic hemorrhage (P = 0.026), and African American race (P = 0.023). In the latter, vitreous opacity density was associated with maternal diabetes (P = 0.049). CONCLUSIONS: Our investigational handheld SS-OCT achieved high-quality vitreoretinal images. In our study cohort, punctate vitreous opacities were a frequent finding in infants born at term and those born prematurely, with increased density in those born prematurely, particularly those with severe ROP.

Tri-zone flame spatial structure imaging combined with endogenic polarized scattering.

We propose a multi-mode optical imaging method to retrieve the 2D and 3D spatial structures of the preheating, reaction, and recombination zones of an axisymmetric steady flame. In the proposed method, an infrared camera, a visible light monochromatic camera, and a polarization camera are triggered synchronously to capture 2D flame images, and their corresponding 3D images are reconstructed by combining different projection position images. The results of the experiments conducted indicate that the infrared and visible light images represent the flame preheating and flame reaction zones, respectively. The polarized image can be obtained by computing the degree of linear polarization (DOLP) of raw images captured by the polarization camera. We discover that the highlighted regions in the DOLP images lie outside the infrared and visible light zones; they are insensitive to the flame reaction and have different spatial structures for different fuels. We deduce that the combustion product particles cause endogenic polarized scattering, and that the DOLP images represent the flame recombination zone. This study focuses on the combustion mechanisms, such as the formation of combustion products and quantitative flame composition and structure.

Choroidal Thickness by Handheld Swept-Source Optical Coherence Tomography in Term Newborns.

Purpose: To describe normative values for choroidal thickness in newborns and characterize their relationship to vitreoretinal features. Methods: Term newborns underwent awake, handheld swept-source optical coherence tomography (SS-OCT) in this prospective cohort study. An automated segmentation algorithm followed by manual adjustments measured choroidal thickness at the fovea and five perifoveal locations. Two masked, trained graders, with a third mediating disagreements, analyzed scans for vitreoretinal findings. OCT vitreoretinal findings, including dome-shaped macula, subretinal fluid, punctate hyperreflective vitreous opacities, persistent inner retinal layers, foveal ellipsoid zone, tractional and non-tractional vitreous bands, epiretinal membrane, cystoid macular edema, vessel elevation, scalloped retinal layers, hyporeflective vessels, and retinal spaces, were assessed and correlated with foveal choroidal thickness using a generalized linear mixed model. Results: Fifty-nine eyes of 39 infants (mean gestational age, 39.5 weeks; 18 male, 46%) were included. Mean foveal choroidal thickness was 455.5 ± 93.9 µm. Choroid was thinner inferonasally (343.6 ± 106.2 µm) compared to superonasally (368.4 ± 92.9 µm; P = 0.03) and superotemporally (369.6 ± 100.6 µm; P = 0.02). Thinner foveal choroidal thickness was associated with absence of a foveal ellipsoid zone (437.1 ± 78.5 µm vs. 553.7 ± 93.9 µm; P = 0.02). Choroidal thickness was not significantly associated with other OCT findings. Conclusions: We identified an association between thinner choroid and foveal immaturity. Additional study is needed to determine whether choroidal development impacts visual outcomes. Translational Relevance: Handheld SS-OCT achieved normative measurements for choroidal thickness across the macula in term newborns, providing a foundation for future investigations into the role of choroidal development in infancy.

Enhanced temporal and spatial resolution in super-resolution covariance imaging algorithm with deconvolution optimization.

Based on the numerical analysis that covariance exhibits superior statistical precision than cumulant and variance, a new SOFI algorithm by calculating the n orders covariance for each pixel is presented with an almost 2n -fold resolution improvement, which can be enhanced to 2n via deconvolution. An optimized deconvolution is also proposed by calculating the (n + 1) order SD associated with each n order covariance pixel, and introducing the results into the deconvolution as a damping factor to suppress noise generation. Moreover, a re-deconvolution of the covariance image with the covariance-equivalent point spread function is used to further increase the final resolution by above 2-fold. Simulated and experimental results show that this algorithm can significantly increase the temporal-spatial resolution of SOFI, meanwhile, preserve the sample's structure. Thus, a resolution of 58 nm is achieved for 20 experimental images, and the corresponding acquisition time is 0.8 seconds.

Thermoacoustic Imaging and Therapy Guidance based on Ultra-short Pulsed Microwave Pumped Thermoelastic Effect Induced with Superparamagnetic Iron Oxide Nanoparticles.

Multifunctional nanoparticle-mediated imaging and therapeutic techniques are promising modalities for accurate localization and targeted treatment of cancer in clinical settings. Thermoacoustic (TA) imaging is highly sensitive to detect the distribution of water, ions or specific nanoprobes and provides excellent resolution, good contrast and superior tissue penetrability. TA therapy is a potential non-invasive approach for the treatment of deep-seated tumors. In this study, human serum albumin (HSA)-functionalized superparamagnetic iron oxide nanoparticle (HSA-SPIO) is used as a multifunctional nanoprobe with clinical application potential for MRI, TA imaging and treatment of tumor. In addition to be a MRI contrast agent for tumor localization, HSA-SPIO can absorb pulsed microwave energy and transform it into shockwave via the thermoelastic effect. Thereby, the reconstructed TA image by detecting TA signal is expected to be a sensitive and accurate representation of the HSA-SPIO accumulation in tumor. More importantly, owing to the selective retention of HSA-SPIO in tumor tissues and strong TA shockwave at the cellular level, HSA-SPIO induced TA effect under microwave-pulse radiation can be used to highly-efficiently kill cancer cells and inhibit tumor growth. Furthermore, ultra-short pulsed microwave with high excitation efficiency and deep penetrability in biological tissues makes TA therapy a highly-efficient anti-tumor modality on the versatile platform. Overall, HSA-SPIO mediated MRI and TA imaging would offer more comprehensive diagnostic information and enable dynamic visualization of nanoagents in the tumorous tissue thereby tumor-targeted therapy.

Imaging-guided photoacoustic drug release and synergistic chemo-photoacoustic therapy with paclitaxel-containing nanoparticles.

Here, a novel triggered drug release modality was developed for oncotherapy. Paclitaxel (PTX), perfluorohexane (PFH) and gold nanorods (AuNRs) loaded nanoparticles (PTX-PAnP) were synthesized. Folic acid (FA) conjugated PTX-PAnP (PTX-PAnP-FA) could be selectively taken into folate receptor-overexpressed tumor cells. Upon pulsed laser irradiation, the PTX-PAnP-FA could be rapidly destructed because of the PFH vaporization, resulting in fast drug release, which induced apoptosis of cancer cells efficiently. Stimulated fragmentation of the PTX-PAnP-FA nanoparticles can facilitate multiple mechanisms such as bubble implosion, shockwave generation, and sonoporation that further enhance the therapeutic efficiency. The in vivo therapy study further confirmed this new approach resulted in efficient tumor suppression. The results demonstrate a unique drug release mechanism based on photoacoustic effect. It provides an all-in-one platform for photoacoustic image-guided drug release and synergistic chemo-photoacoustic therapy.

Imaging-guided high-efficient photoacoustic tumor therapy with targeting gold nanorods.

Photoacoustic therapy using the large photoacoustic effect of agents for selectively killing cancer cells is demonstrated. Herein, a highly efficient photoacoustic treatment using gold nanorods (AuNRs) and its antitumor effect are reported. Folic acid conjugated AuNRs are designed to specifically target folate receptor-expressing cancer cells. Following photoacoustic treatment, most of the cancer cells with intracellular AuNRs die within 20s. Compared with single-walled carbon nanotubes and indocyanine green containing nanoparticles, AuNRs can produce much stronger shock waves by absorbing the optical energy and thus induced the more efficient cell death at equal molar concentrations. In addition, the laser-induced shock waves can be detected for photoacoustic imaging. Our in vivo experiments demonstrated that the AuNR-mediated photoacoustic treatment resulted in efficient tumor suppression in mice. Thus, both efficient cancer cell diagnostics and selective photoacoustic treatment can be realized with a single-particle formulation. FROM THE CLINICAL EDITOR: Nanotechnology has enabled the development of many novel methods for the treatment of cancer. One of these is photoacoustic therapy. In this article, the authors demonstrated the efficacy of Folic acid conjugated gold nanorods in killing cancer cells after photoacoustic treatment. The findings should provide impetus for future clinical studies.

In vivo photoacoustic therapy with cancer-targeted indocyanine green-containing nanoparticles.

AIM: The objective of this work was to study the photoacoustic effect of a special nanoparticle for selective cancer cell killing both in vitro and in vivo. MATERIALS & METHODS: The nanoparticles (NPs) consisting of indocyanine green (ICG), phospholipid-polyethylene glycol (PL-PEG) and folic acid (FA) were used as cancer-targeting nanoprobes. Cancer cells incubated with the ICG-PL-PEG-FA solution were exposed to laser pulses. Finally, tumors in mice were treated with photoacoustic technique. RESULTS: High selectivity of the photoacoustic destruction of cancer cells was observed. The tumors in mice after photoacoustic treatment showed a much slower growth rate. CONCLUSION: The destruction of the cells was due to the photoacoustic effect originating from the NPs. The ICG-PL-PEG NP-based photoacoustic therapy would be a safe and highly efficient cancer treatment technique.