ABSTRACT
Compressed ultrafast photography (CUP) can capture irreversible or difficult-to-repeat dynamic scenes at the imaging speed of more than one billion frames per second, which is obtained by compressive sensing-based image reconstruction from a compressed 2D image through the discretization of detector pixels. However, an excessively high data compression ratio in CUP severely degrades the image reconstruction quality, thereby restricting its ability to observe ultrafast dynamic scenes with complex spatial structures. To address this issue, a discrete illumination-based CUP (DI-CUP) with high fidelity is reported. In DI-CUP, the dynamic scenes are loaded into an ultrashort laser pulse train with controllable sub-pulse number and time interval, thus the data compression ratio, as well as the overlap between adjacent frames, is greatly decreased and flexibly controlled through the discretization of dynamic scenes based on laser pulse train illumination, and high-fidelity image reconstruction can be realized within the same observation time window. Furthermore, the superior performance of DI-CUP is verified by observing femtosecond laser-induced ablation dynamics and plasma channel evolution, which are hardly resolved in the spatial structures using conventional CUP. It is anticipated that DI-CUP will be widely and dependably used in the real-time observations of various ultrafast dynamics.
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The projection of fringes plays an essential role in many applications, such as fringe projection profilometry and structured illumination microscopy. However, these capabilities are significantly constrained in environments affected by optical scattering. Although recent developments in wavefront shaping have effectively generated high-fidelity focal points and relatively simple structured images amidst scattering, the ability to project fringes that cover half of the projection area has not yet been achieved. To address this limitation, this study presents a fringe projector enabled by a neural network, capable of projecting fringes with variable periodicities and orientation angles through scattering media. We tested this projector on two types of scattering media: ground glass diffusers and multimode fibers. For these scattering media, the average Pearson's correlation coefficients between the projected fringes and their designed configurations are 86.9% and 79.7%, respectively. These results demonstrate the effectiveness of the proposed neural network enabled fringe projector. This advancement is expected to broaden the scope of fringe-based imaging techniques, making it feasible to employ them in conditions previously hindered by scattering effects.
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Ultrafast imaging can capture the dynamic scenes with a nanosecond and even femtosecond temporal resolution. Complementarily, phase imaging can provide the morphology, refractive index, or thickness information that intensity imaging cannot represent. Therefore, it is important to realize the simultaneous ultrafast intensity and phase imaging for achieving as much information as possible in the detection of ultrafast dynamic scenes. Here, we report a single-shot intensity- and phase-sensitive compressive sensing-based coherent modulation ultrafast imaging technique, shortened as CS-CMUI, which integrates coherent modulation imaging, compressive imaging, and streak imaging. We theoretically demonstrate through numerical simulations that CS-CMUI can obtain both the intensity and phase information of the dynamic scenes with ultrahigh fidelity. Furthermore, we experimentally build a CS-CMUI system and successfully measure the intensity and phase evolution of a multimode Q-switched laser pulse and the dynamical behavior of laser ablation on an indium tin oxide thin film. It is anticipated that CS-CMUI enables a profound comprehension of ultrafast phenomena and promotes the advancement of various practical applications, which will have substantial impact on fundamental and applied sciences.
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Oxygen-induced retinopathy (OIR) animal model is widely used for retinopathy of prematurity (ROP) researches. The purpose of this study was to identify proteins and related pathways of OIR with or without anti-vascular endothelial growth factor (VEGF) treatment, for use as biomarkers in diagnosing and treating ROP. Nine samples were subjected to proteomic analysis. Retina specimens were collected from 3 OIR mice, 3 OIR mice with anti-VEGF treatment and 3 normal mice (control group). Liquid chromatography-tandem mass spectrometry analysis was performed using the 4D label-free technique. Statistically significant differentially expressed proteins, gene ontology (GO) terms, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway representations, InterPro (IPR) and protein interactions were analyzed. In total, 4585 unique proteins were identified as differentially expressed proteins (DEPs). Enrichment analysis of the GO and KEGG indicated functional clusters related to peptide biosynthetic and metabolic process, cellular macromolecule biosynthetic process and nucleic acid binding in OIR group. For anti-VEGF treatment group, DEPs were clustered in DNA replication, PI3K/Akt signaling pathway and Jak/STAT signaling pathway. Proteomic profiling is useful for the exploration of molecular mechanisms of OIR and mechanisms of anti-VEGF treatment. These findings may be useful for identification of novel biomarkers for ROP pathogenesis and treatment.
Subject(s)
Oxygen , Proteomics , Retinopathy of Prematurity , Vascular Endothelial Growth Factor A , Animals , Oxygen/metabolism , Mice , Proteomics/methods , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor A/genetics , Retinopathy of Prematurity/drug therapy , Retinopathy of Prematurity/metabolism , Signal Transduction/drug effects , Disease Models, Animal , Tandem Mass Spectrometry , Gene Ontology , Chromatography, Liquid , Retina/metabolism , Retina/drug effects , Retina/pathologyABSTRACT
The present study aimed to establish and evaluate a preclinical model of steroid-associated osteonecrosis (SAON) in mice. Sixteen 24-week-old male C57BL/6 mice were used to establish SAON by two intraperitoneal injections of lipopolysaccharide (LPS), followed by three subcutaneous injections of methylprednisolone (MPS). Each injection was conducted on working day, with an interval of 24 h. Six cycles of injections were conducted. Additional twelve mice (age- and gender-matched) were used as normal controls. At 2 and 6 weeks after completing induction, bilateral femora and bilateral tibiae were collected for histological examination, micro-CT scanning, and bulk RNA sequencing. All mice were alive until sacrificed at the indicated time points. The typical SAON lesion was identified by histological evaluation at week 2 and week 6 with increased lacunae and TUNEL+ osteocytes. Micro-CT showed significant bone degeneration at week 6 in SAON model. Histology and histomorphometry showed significantly lower Runx2+ area, mineralizing surface (MS/BS), mineral apposition rate (MAR), bone formation rate (BFR/BS), type H vessels, Ki67+ (proliferating) cells, and higher marrow fat fraction, osteoclast number and TNFα+ areas in SAON group. Bulk RNA-seq revealed changed canonical signaling pathways regulating cell cycle, angiogenesis, osteogenesis, and osteoclastogenesis in the SAON group. The present study successfully established SAON in mice with a combination treatment of LPS and MPS, which could be considered a reliable and reproducible animal model to study the pathophysiology and molecular mechanism of early-stage SAON and to develop potential therapeutic approaches for the prevention and treatment of SAON.
Subject(s)
Lipopolysaccharides , Osteonecrosis , Male , Mice , Animals , Disease Models, Animal , Mice, Inbred C57BL , Osteonecrosis/drug therapy , Steroids , Osteogenesis , Methylprednisolone/therapeutic useABSTRACT
AIM: To evaluate scleral buckling (SB) surgery using a non-contact wide-field viewing system and 23-gauge intraocular illumination for the treatment of rhegmatogenous retinal detachment in silicone oil (SO)-filled eyes. METHODS: Totally 9 patients (9 eyes) with retinal detachment in SO-filled eyes were retrospectively analyzed. All patients underwent non-contact wide-field viewing system-assisted buckling surgery with 23-gauge intraocular illumination. SO was removed at an appropriate time based on recovery. The patients were followed up for at least 3mo after SO removal. Retinal reattachment, complications, visual acuity and intraocular pressure (IOP) before and after surgery were observed. RESULTS: Patients were followed up for a mean of 8.22mo (3-22mo) after SO removal. All patients had retinal reattachment. At the final follow-up, visual acuity showed improvement for 8 patients, and no change for 1 patient. The IOP was high in 3 patients before surgery, but it stabilized after treatment; it was not affected in the other patients. None of the patients had infections, hemorrhage, anterior ischemia, or any other complication. CONCLUSION: This new non-contact wide-field viewing system-assisted SB surgery with 23-gauge intraocular illumination is effective and safe for retinal detachment in SO-filled eyes.
ABSTRACT
Compressed ultrafast photography (CUP) is a novel two-dimensional (2D) imaging technique to capture ultrafast dynamic scenes. Effective image reconstruction is essential in CUP systems. However, existing reconstruction algorithms mostly rely on image priors and complex parameter spaces. Therefore, in general, they are time-consuming and result in poor imaging quality, which limits their practical applications. In this paper, we propose a novel reconstruction algorithm, to the best of our knowledge, named plug-in-plug-fast deep video denoising net-total variation (PnP-TV-FastDVDnet), which exploits an image's spatial features and correlation features in the temporal dimension. Therefore, it offers higher-quality images than those in previously reported methods. First, we built a forward mathematical model of the CUP, and the closed-form solution of the three suboptimization problems was derived according to plug-in and plug-out frames. Secondly, we used an advanced video denoising algorithm based on a neural network named FastDVDnet to solve the denoising problem. The peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM) are improved on actual CUP data compared with traditional algorithms. On benchmark and real CUP datasets, the proposed method shows the comparable visual results while reducing the running time by 96% over state-of-the-art algorithms.
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Purpose: The purpose of this study was to investigate the quantitative retinal vascular morphological characteristics of Retinopathy of Prematurity (ROP) and Familial Exudative Vitreoretinopathy (FEVR) in the newborn by the application of a deep learning network with artificial intelligence. Methods: Standard 130-degree fundus photographs centered on the optic disc were taken in the newborns. The deep learning network provided segmentation of the retinal vessels and the optic disc (OD). Based on the vessel segmentation, the vascular morphological characteristics, including avascular area, vessel angle, vessel density, fractal dimension (FD), and tortuosity, were automatically evaluated. Results: 201 eyes of FEVR, 289 eyes of ROP, and 195 eyes of healthy individuals were included in this study. The deep learning system of blood vessel segmentation had a sensitivity of 72% and a specificity of 99%. The vessel angle in the FEVR group was significantly smaller than that in the normal group and ROP group (37.43 ± 5.43 vs. 39.40 ± 5.61, 39.50 ± 5.58, P = 0.001, < 0.001 respectively). The normal group had the lowest vessel density, the ROP group was in between, and the FEVR group had the highest (2.64 ± 0.85, 2.97 ± 0.92, 3.37 ± 0.88 respectively). The FD was smaller in controls than in the FEVR and ROP groups (0.984 ± 0.039, 1.018 ± 0.039 and 1.016 ± 0.044 respectively, P < 0.001). The ROP group had the most tortuous vessels, while the FEVR group had the stiffest vessels, the controls were in the middle (11.61 ± 3.17, 8.37 ± 2.33 and 7.72 ± 1.57 respectively, P < 0.001). Conclusions: The deep learning technology used in this study has good performance in the quantitative analysis of vascular morphological characteristics in fundus photography. Vascular morphology was different in the newborns of FEVR and ROP compared to healthy individuals, which showed great clinical value for the differential diagnosis of ROP and FEVR.
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Purpose: To investigate the characteristics of optical coherence tomography (OCT) and aqueous humor cytokine differences between acute and chronic central serous chorioretinopathy (CSC) and to evaluate the relevance of these findings.Methods: This was a cross-sectional, observational study. Patients with CSC were divided into acute and chronic groups based on the symptom duration and were compared with normal controls. Best-corrected visual acuity (BCVA), central macular thickness (CMT), subfoveal choroidal thickness (CT), hyperreflective foci (HF), and cytokines including vascular endothelial growth factor (VEGF), interleukin (IL)-6, IL-8, IL-10, interferon-inducible protein-10 (IP-10), and monocyte chemoattractant protein-1 (MCP-1) were used as comparison metrics.Results: A total of 62 patients (62 eyes) with CSC (22 with acute CSC and 40 with chronic CSC) and 35 patients as controls were included in this study. The chronic CSC group had significantly older average ages and worse BCVA than the acute CSC group (both p < 0.05). Both CSC groups showed significant increases in CMT and CT (both p < 0.05). In chronic CSC, the CMT was thinner, with more HF in the neuroretina (p = 0.034). VEGF levels were significantly higher in patients with chronic CSC than in those with acute CSC and controls (p < 0.05). The levels of inflammatory cytokines showed no significant difference between the CSC and control groups. Spearman's correlation analysis showed that the number of HF was positively correlated with disease duration (r = 0.311, p = 0.014), logMAR BCVA (r = 0.487, P < 0.001) and MCP-1 levels (r = 0.256, p = 0.045).Conclusions: Chronicity of CSC could lead to upregulation of VEGF. HF was associated with a more severe visual impairment in CSC patients and had relations with the levels of MCP-1.
Subject(s)
Central Serous Chorioretinopathy , Humans , Central Serous Chorioretinopathy/diagnosis , Vascular Endothelial Growth Factor A , Tomography, Optical Coherence/methods , Cytokines/metabolism , Cross-Sectional Studies , Chronic Disease , Fluorescein Angiography/methods , Retrospective StudiesABSTRACT
BACKGROUND: Whether polymorphic Human Leukocyte Antigen (HLA)-A, HLA-B and HLA-DRB1 alleles were associated with acute liver disease after hepatitis B virus (HBV) infections was investigated. METHODS: In this study, from initially 100 participants in each group, HLA-A, HLA-B and HLA-DRB1 sequences were available from 86 acute hepatitis B (AHB) patients and from 84 HBV-resistant individuals (controls), using sequencing-based typing allele groups and alleles that exhibited differences in distribution between the case and control groups were subjected to chi-squared and logistic regression analyses to identify those associated with AHB. A dose response analysis was also performed on the effect of HLA-A*24:02 allele number on acute liver disease following HBV infection. RESULTS: The frequency distribution of HLA-B and HLA-DRB1 alleles in the control group were in Hardy-Weinberg Equilibrium (P > .05). HLA-A*24:02 (χ2 = 6.949, P = .008) occurred most frequently in the AHB and HLA-DRB1*12:02 (χ2 = 7.768, P = .005) in the control group. With adjustment for sex, the logistic regression model showed that the HLA-A*24:02 allele was significantly associated with AHB liver injury (P = .0326, OR = 2.270, 95% CI: 1.070-4.816), whereas the other HLA-A, HLA-B, and HLA-DRB1 alleles were not (P > .05). A linear response was observed for the association between HLA-A*24:02 allele number and acute liver disease after HBV infections (χ2 = 4.428, P = .025). CONCLUSION: The HLA-A*24:02 allele may influence the severity of the cellular response to HBV infection, increasing the elimination of HBV-infected hepatocytes. The HLA-A*24:02 allele may be a potential screening marker for identifying people or regional populations in China at higher risk of acute liver disease following HBV infection.
Subject(s)
HLA-A Antigens , Hepatitis B , Adult , Humans , Alleles , China , East Asian People , Gene Frequency , Genetic Predisposition to Disease , Hepatitis B/genetics , Hepatitis B virus , HLA-A Antigens/genetics , HLA-B Antigens , HLA-DRB1 Chains/geneticsABSTRACT
This study developed a novel frequency-doubled Fabry-Perot cavity method based on a femtosecond laser of 1030 nm, 190 fs, 1 mJ, and 1 kHz. The time interval (60-1000 ps) and attenuation ratio (0.5-0.9) between adjacent sub-pulses of the 515 nm pulse train were able to be easily adjusted, while the efficiency was up to 50% and remained unchanged. Extremely high-quality low-spatial-frequency LIPSS (LSFL) was efficiently fabricated on an indium tin oxide (ITO) film using a pulse train with a time interval of 150 ps and attenuation ratio of 0.9 focused with a cylindrical lens. Compared with the LSFL induced by the primary Gaussian pulse, the uniformity of the LSFL period was enhanced from 481 ± 41 nm to 435 ± 8 nm, the divergence of structural orientation angle was reduced from 15.6° to 3.7°, and the depth was enhanced from 74.21 ± 14.35 nm to 150.6 ± 8.63 nm. The average line edge roughness and line height roughness were only 7.34 nm and 2.06 nm, respectively. The depths and roughness values were close to or exceeded those of resist lines made by the interference lithography. Compared with the common Fabry-Perot cavity, the laser energy efficiency of the pulse trains and manufacturing efficiency were enhanced by factors of 19 and 25. A very colorful "lotus" pattern with a size of 30×28 mm2 was demonstrated, which was covered with high-quality LSFLs fabricated by a pulse train with optimized laser parameters. Pulse trains can efficiently enhance and prolong the excitation of surface plasmon polaritons, inhibit deposition particles, depress ablation residual heat and thermal shock waves, and eliminate high-spatial-frequency LIPSS formed on LSFL, therefore, producing extremely high-quality LSFL on ITO films.
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The knowledge of osteoarthritis (OA) has nowadays been extended from a focalized cartilage disorder to a multifactorial disease. Although recent investigations have reported that infrapatellar fat pad (IPFP) can trigger inflammation in the knee joint, the mechanisms behind the role of IPFP on knee OA progression remain to be defined. Here, dysregulated osteopontin (OPN) and integrin ß3 signaling are found in the OA specimens of both human and mice. It is further demonstrated that IPFP-derived OPN participates in OA progression, including activated matrix metallopeptidase 9 in chondrocyte hypertrophy and integrin ß3 in IPFP fibrosis. Motivated by these findings, an injectable nanogel is fabricated to provide sustained release of siRNA Cd61 (RGD- Nanogel/siRNA Cd61) that targets integrins. The RGD- Nanogel possesses excellent biocompatibility and desired targeting abilities both in vitro and in vivo. Local injection of RGD- Nanogel/siRNA Cd61 robustly alleviates the cartilage degeneration, suppresses the advancement of tidemark, and reduces the subchondral trabecular bone mass in OA mice. Taken together, this study provides an avenue for developing RGD- Nanogel/siRNA Cd61 therapy to mitigate OA progression via blocking OPN-integrin ß3 signaling in IPFP.
Subject(s)
Cartilage, Articular , Osteoarthritis, Knee , Humans , Mice , Animals , Integrin beta3 , Nanogels , Osteopontin , Knee Joint , Adipose Tissue , RNA, Small Interfering/genetics , OligopeptidesABSTRACT
The valence state conversion of lanthanide ions induced by femtosecond laser fields has attracted considerable attention due to their potential applications in areas like high-density optical storage. However, the physical mechanisms involved in valence state conversions still remain unclear. Here, we report the first experimental study of controlling the reduction of trivalent samarium ions to divalent ones in sodium aluminoborate glass by varying the polarization status of the 800 nm femtosecond laser field. As the laser field is varied from linear to circular polarization, the reduction efficiency can be greatly decreased by about fifty percent. This polarization-dependent reduction behavior is found to directly correlate with the nonresonant two-photon 4f-4f absorption probability of the trivalent samarium ions in both experiment and theory. Multiphoton excited charge transfer between oxygen and samarium is considered to be responsible for the photoreduction. Our work demonstrates a controllable and effective way in tuning the valence state conversion efficiency and sheds light on the underlying mechanisms.
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Structured illumination microscopy (SIM), as a flexible tool, has been widely applied to observing subcellular dynamics in live cells. It is noted, however, that SIM still encounters a problem with theoretical resolution limitation being only twice over wide-field microscopy, where imaging of finer biological structures and dynamics are significantly constrained. To surpass the resolution limitation of SIM, we developed an image postprocessing method to further improve the lateral resolution of SIM by an untrained neural network, i.e., deep resolution-enhanced SIM (DRE-SIM). DRE-SIM can further extend the spatial frequency components of SIM by employing the implicit priors based on the neural network without training datasets. The further super-resolution capability of DRE-SIM is verified by theoretical simulations as well as experimental measurements. Our experimental results show that DRE-SIM can achieve the resolution enhancement by a factor of about 1.4 compared with conventional SIM. Given the advantages of improving the lateral resolution while keeping the imaging speed, DRE-SIM will have a wide range of applications in biomedical imaging, especially when high-speed imaging mechanisms are integrated into the conventional SIM system.
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Hyperspectrally compressed ultrafast photography (HCUP) based on compressed sensing and time- and spectrum-to-space mappings can simultaneously realize the temporal and spectral imaging of non-repeatable or difficult-to-repeat transient events with a passive manner in single exposure. HCUP possesses an incredibly high frame rate of tens of trillions of frames per second and a sequence depth of several hundred, and therefore plays a revolutionary role in single-shot ultrafast optical imaging. However, due to ultra-high data compression ratios induced by the extremely large sequence depth, as well as limited fidelities of traditional algorithms over the image reconstruction process, HCUP suffers from a poor image reconstruction quality and fails to capture fine structures in complex transient scenes. To overcome these restrictions, we report a flexible image reconstruction algorithm based on a total variation (TV) and cascaded denoisers (CD) for HCUP, named the TV-CD algorithm. The TV-CD algorithm applies the TV denoising model cascaded with several advanced deep learning-based denoising models in the iterative plug-and-play alternating direction method of multipliers framework, which not only preserves the image smoothness with TV, but also obtains more priori with CD. Therefore, it solves the common sparsity representation problem in local similarity and motion compensation. Both the simulation and experimental results show that the proposed TV-CD algorithm can effectively improve the image reconstruction accuracy and quality of HCUP, and may further promote the practical applications of HCUP in capturing high-dimensional complex physical, chemical and biological ultrafast dynamic scenes.
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Purpose: To investigate and compare the aqueous humor (AH) concentration and vitreous mass of cytokines in high myopias (HM) with and without myopic choroidal neovascularization (mCNV). And the correlations between cytokines and the size of CNVs on optical coherence tomography angiography (OCTA) images were also be analyzed. Methods: This observational study included 56 highly myopic eyes with and without CNV and 57 control eyes with cataracts. AH samples were obtained prior to the intravitreal injection of anti-VEGF and cataract surgery. This study measured multiple inflammatory cytokines including VEGF, interleukin (IL)-6, IL-8, IL-10, interferon-inducible protein-10 (IP-10), and monocyte chemotactic protein-1 (MCP-1) by multiplex bead assay. AH cytokine level, axial length, and vitreous volume were used to calculate the vitreous mass of cytokines. Results: The vitreous mass of VEGF in eyes with mCNV was significantly higher than that in control group. However, the difference in AH concentration of VEGF between high myopias with mCNV was not observed. Inflammatory cytokines were upregulated (IL-6, IL-10, and MCP-1) in highly myopic eyes both with and without mCNV (all P<0.05). There was also a significant difference in the vitreous mass of IL-8 and IP-10 among all three groups (P<0.05). Conclusion: We confirmed the secretion of VEGF increased in eyes with mCNV from a new perspective. The development of both HM and mCNV were related to inflammatory cytokines and the upregulation of inflammatory cytokines may precede upregulation of VEGF. The vitreous mass might be tried as a more reliable potential biomarker in eyes with longer axial length.
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Purpose: To investigate the associations between cytokine levels in the aqueous humor (AH) and hyperreflective foci (HF) on spectral-domain optical coherence tomography (SD-OCT) in neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV). Methods: The prospective study included 63 eyes with nAMD, 44 with PCV, and 43 with cataracts (Controls). AH samples were obtained before anti-vascular endothelial growth factor (VEGF) therapy or cataract surgery. Cytokines interleukin 6 (IL-6), IL-8, IL-10, interferon-inducible protein 10 (IP-10), monocyte chemotactic protein 1 (MCP-1), and VEGF were measured by multiplex bead assay. Best-corrected visual acuity (BCVA), central macular thickness (CMT), and the number of HF were evaluated at baseline and 1 month after anti-VEGF treatment. Results: No significances difference in IL-6 and IL-8 levels were noted among the three groups (P = 0.370 and P = 0.067). VEGF, IP-10, and IL-10 levels were significantly higher in nAMD and PCV groups than in Controls (all P < 0.05). In nAMD, HF was positively correlated with VEGF (r s = 0.300, P = 0.025) and in eyes with HF group, VEGF and IL-10 were significantly higher than those without HF (P = 0.008 and P = 0.022). In PCV, no correlation was observed between HF and cytokines (all P > 0.05). After anti-VEGF treatment, patients with HF in nAMD and PCV were predisposed to worse visual outcomes (P = 0.022 and P = 0.015) and a significantly greater reduction in CMT (P = 0.001 and P = 0.057). And nAMD patients with HF were more sensitive to anti-VEGF treatment than those without HF (P = 0.029). Conclusions: In the nAMD group, HF was positively correlated with VEGF. Patients in nAMD with HF had elevated levels of VEGF and IL-10 and responded favorably to anti-VEGF. HF might serve as an inflammatory biomarker and a predictive factor for therapeutic efficacy in patients with nAMD.
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Being capable of passively capturing transient scenes occurring in picoseconds and even shorter time with an extremely large sequence depth in a snapshot, compressed ultrafast photography (CUP) has aroused tremendous attention in ultrafast optical imaging. However, the high compression ratio induced by large sequence depth brings the problem of low image quality in image reconstruction, preventing CUP from observing transient scenes with fine spatial information. To overcome these restrictions, we propose an efficient image reconstruction algorithm with multi-scale (MS) weighted denoising based on the plug-and-play (PnP) based alternating direction method of multipliers (ADMM) framework for multi-channel coupled CUP (MC-CUP), named the MCMS-PnP algorithm. By removing non-Gaussian distributed noise using weighted MS denoising during each iteration of the ADMM, and adaptively adjusting the weights via sufficiently exploiting the coupling information among different acquisition channels collected by MC-CUP, a synergistic combination of hardware and algorithm can be realized to significantly improve the quality of image reconstruction. Both simulation and experimental results demonstrate that the proposed adaptive MCMS-PnP algorithm can effectively improve the accuracy and quality of reconstructed images in MC-CUP, and extend the detectable range of CUP to transient scenes with fine structures.
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Splenomegaly is common in malaria, but splenic infarction is a rare complication of malaria. We report a case of a patient with Plasmodium falciparum infection who developed abdominal pain, reappearance of fever, elevated D-dimer during treatment, and abdominal CT confirmed splenic infarction. The abdominal pain was relieved and the fever subsided by analgesic and anticoagulant therapy. Six months later, abdominal CT showed splenic recovery. As a result, splenic infarction should be considered when a patient with malaria developed abdominal pain, reappearance of fever and elevated blood D-dimer during treatment. In the absence of surgical indications, conservative medical treatment is effective.