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Prostate cancer (PCa), a prevalent malignancy among elderly males, exhibits a notable rate of advancement, even when subjected to conventional androgen deprivation therapy or chemotherapy. An effective progression prediction model would prove invaluable in identifying patients with a higher progression risk. Using bioinformatics strategies, we integrated diverse data sets of PCa to construct a novel risk model predicated on gene expression and progression-free survival (PFS). The accuracy of the model was assessed through validation using an independent data set. Eight genes were discerned as independent prognostic factors and included in the prediction model. Patients assigned to the high-risk cohort demonstrated a diminished PFS, and the areas under the curve of our model in the validation set for 1-year, 3-year, and 5-year PFS were 0.9325, 0.9041 and 0.9070, respectively. Additionally, through the application of single-cell RNA sequencing to two castration-related prostate cancer (CRPC) samples and two hormone-related prostate cancer (HSPC) samples, we discovered that luminal cells within CRPC exhibited an elevated risk score. Subsequent molecular biology experiments corroborated our findings, illustrating heightened SYK expression levels within tumour tissues and its contribution to cancer cell migration. We found that the knockdown of SYK could inhibit migration in PCa cells. Our progression-related risk model demonstrated the potential prognostic value of SYK and indicated its potential as a target for future diagnosis and treatment strategies in PCa management.
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Biologia Computacional , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata , Masculino , Humanos , Biologia Computacional/métodos , Prognóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/diagnóstico , Perfilação da Expressão Gênica , Biomarcadores Tumorais/genética , Fatores de Risco , Linhagem Celular TumoralRESUMO
Xylan is a crosslinking polymer that plays an important role in the assembly of heterogeneous cell wall structures in plants. The pollen wall, a specialized cell wall matrix, exhibits diverse sculpted patterns that serve to protect male gametophytes and facilitate pollination during plant reproduction. However, whether xylan is precisely anchored into clusters and its influence on pollen wall patterning remain unclear. Here, we report xylan clustering on the mature pollen surface in different plant species that is indispensable for the formation of sculpted exine patterns in dicot and monocot plants. Chemical composition analyses revealed that xylan is generally present at low abundance in the mature pollen of flowering plants and shows plentiful variations in terms of substitutions and modifications. Consistent with the expression profiles of their encoding genes, genetic characterization revealed IRREGULAR XYLEM10-LIKE (IRX10L) and its homologous proteins in the GT47 family of glycosyltransferases as key players in the formation of these xylan micro-/nano-compartments on the pollen surface in Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa). A deficiency in xylan biosynthesis abolished exine patterning on pollen and compromised male fertility. Therefore, our study outlines a mechanism of exine patterning and provides a tool for manipulating male fertility in crop breeding.
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Proteínas de Arabidopsis , Arabidopsis , Oryza , Xilanos/metabolismo , Melhoramento Vegetal , Pólen/genética , Pólen/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/metabolismo , Mutação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Rhodopsin-mediated autosomal dominant retinitis pigmentosa (RHO-adRP) causes progressive vision loss and is potentially incurable, accounting for 25% of adRP cases. Studies on RHO-adRP mechanism were at large based on the biochemical and cellular properties, especially class-3. Nonetheless, the absence of an appropriate model for class-3 RHO-adRP has impeded comprehensive exploration. Here, induced pluripotent stem cells (iPSCs) were generated from a healthy control and two sibling RP patients with the same point mutation, c.403C>T (p.R135W). The first three-dimensional (3D) retinal organoid model of a class-3 RHO point mutation from patient-derived iPSCs was generated. Significant defects were observed in rod photoreceptors in terms of localization, morphology, transcriptional profiling and single cell resolution, to better understand the human disease resulting from RHO mutations from a developmental perspective. This first human model of class-3 RHO-adRP provides a representation of patient's retina in vitro and displays features of RHO-adRP retinal organoids relevant for therapeutic development.
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Retina , Retinose Pigmentar , Humanos , Retinose Pigmentar/genética , Mutação , Rodopsina/genética , OrganoidesRESUMO
Lung cancer is the main cause of cancer deaths around the world. Nitrosamine 4-(methyl nitrosamine)-1-(3-pyridyl)-1-butanone (NNK) is a tobacco-specific carcinogen of lung cancer. Abundant evidence implicates long noncoding RNAs (lncRNAs) in tumorigenesis. Yet, the effects and mechanisms of lncRNAs in NNK-induced carcinogenesis are still unclear. In this study, we discovered that NNK-induced transformed Beas-2B cells (Beas-2B-NNK) showed increased cell migration and proliferation while decreasing rates of apoptosis. RNA sequencing and differentially expressed lncRNAs analyses showed that lncRNA PSMB8-AS1 was obviously upregulated. Interestingly, silencing the lncRNA PSMB8-AS1 in Beas-2B-NNK cells reduced cell proliferation and migration and produced cell cycle arrest in the G2/M phase along with a decrease in CDK1 expression. Conclusively, our results demonstrate that lncRNA PSMB8-AS1 could promote the malignant characteristics of Beas-2B-NNK cells by regulating CDK1 and affecting the cell cycle, suggesting that it may supply a new prospective epigenetic mechanism for lung cancer.
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Brônquios , Carcinógenos , Ciclo Celular , Proliferação de Células , Células Epiteliais , Nicotiana , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Brônquios/citologia , Brônquios/patologia , Brônquios/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Nicotiana/efeitos adversos , Ciclo Celular/efeitos dos fármacos , Carcinógenos/toxicidade , Nitrosaminas/toxicidade , Linhagem Celular , Movimento Celular/efeitos dos fármacosRESUMO
Innovations in food packaging systems could meet the evolving needs of the market; emerging concepts of non-migrating technologies reduce the negative migration of preservatives from packaging materials, extend shelf life, and improve food quality and safety. Non-migratory packaging activates the surface of inert materials through pretreatment to generate different active groups. The preservative is covalently grafted with the resin of the pretreated packaging substrate through the graft polymerization of the monomer and the coupling reaction of the polymer chain. The covalent link not only provides the required surface properties of the material for a long time but also retains the inherent properties of the polymer. This technique is applied to the processing for durable, stable, and easily controllable packaging widely. This article reviews the principles of various techniques for packaging materials, surface graft modification, and performance characterization of materials after grafting modification. Potential applications in the food industry and future research trends are also discussed.
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Embalagem de Alimentos , Armazenamento de Alimentos , Embalagem de Alimentos/métodos , Polímeros/química , Qualidade dos AlimentosRESUMO
Microglia are resident central nervous system macrophages and the first responders to neural injury. Until recently, microglia have been studied only in animal models with exogenous or transgenic labeling. While these studies provided a wealth of information on the delicate balance between neuroprotection and neurotoxicity within which these cells operate, extrapolation to human immune function has remained an open question. Here we examine key characteristics of retinal macrophage cells in live human eyes, both healthy and diseased, with the unique capabilities of our adaptive optics-optical coherence tomography approach and owing to their propitious location above the inner limiting membrane (ILM), allowing direct visualization of cells. Our findings indicate that human ILM macrophage cells may be distributed distinctly, age differently, and have different dynamic characteristics than microglia in other animals. For example, we observed a macular pattern that was sparse centrally and peaked peripherally in healthy human eyes. Moreover, human ILM macrophage density decreased with age (â¼2% of cells per year). Our results in glaucomatous eyes also indicate that ILM macrophage cells appear to play an early and regionally specific role of nerve fiber layer phagocytosis in areas of active disease. While we investigate ILM macrophage cells distinct from the larger sample of overall retinal microglia, the ability to visualize macrophage cells without fluorescent labeling in the live human eye represents an important advance for both ophthalmology and neuroscience, which may lead to novel disease biomarkers and new avenues of exploration in disease progression.
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Macrófagos/metabolismo , Imagem Molecular , Imagem Óptica , Retina/metabolismo , Retina/patologia , Biomarcadores , Suscetibilidade a Doenças , Glaucoma/diagnóstico , Glaucoma/etiologia , Glaucoma/metabolismo , Humanos , Macrófagos/imunologia , Macula Lutea/metabolismo , Microglia/imunologia , Microglia/metabolismo , Microglia/patologia , Imagem Molecular/métodos , Neuroproteção , Imagem Óptica/métodos , Retina/diagnóstico por imagem , Tomografia de Coerência ÓpticaRESUMO
Background and Objectives: Triple-negative breast cancer (TNBC), a highly aggressive and heterogeneous subtype of breast cancer, accounts for ap-proximately 10-15% of all breast cancer cases. Currently, there is no effective therapeutic target for TNBC. Tu-mor-associated macrophages (TAMs), which can be phenotypically classified into M1 and M2 subtypes, have been shown to influence the prognosis of various cancers, including ovarian cancer. This study aimed to investigate the role of M1/M2 macrophages in the TNBC tumor microenvironment (TME), with a focus on identifying prognostic genes and predicting immunotherapy response. Materials and Methods: The study employed the CIBERSORT algorithm to analyze immune cell expression in the TME. Genes associated with the M1/M2 macrophage ratio were identified using Pearson correlation analysis and used to classify patients into dis-tinct clusters. Dimensionality reduction techniques, including univariate Cox regression and Lasso, were applied to these genes. The expression of prognostic genes was validated through immunohistochemistry. Results: The study found a high prevalence of TAMs in the TME. Among the patient clusters, 109 differentially expressed genes (DEGs) were identified. Three significant DEGs (LAMP3, GZMB, and CXCL13) were used to construct the riskScores. The riskScore model effectively stratified patients based on mortality risk. Gene Set Enrichment Analysis (GSEA) associated the riskScore with several significant pathways, including mismatch repair, JAK/STAT3 signaling, VEGF signaling, antigen processing presentation, ERBB signaling, and P53 signaling. The study also predicted patient sensitivity to im-munotherapy using the riskScores. The expression of the three significant DEGs was validated through immunohisto-chemistry. Conclusions: The study concluded that the riskScore model, based on the M1/M2 macrophage ratio, is a valid prognostic tool for TNBC. The findings underscore the importance of the TME in TNBC progression and prognosis and highlight the po-tential of the riskScore model in predicting immunotherapy response in TNBC patients.
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Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/terapia , Prognóstico , Imunoterapia , Contagem de Células Sanguíneas , Microambiente Tumoral/genéticaRESUMO
BACKGROUND: A new Bacillus thuringiensis X023 (BtX023) with high insecticidal activity was isolated in Hunan Province, China. The addition of metals (Cu, Fe, Mg and Mn) to the medium could influence the formation of spores and/or insecticidal crystal proteins (ICPs). In previous studies, Cu ions considerably increased the synthesis of ICPs by enhancing the synthesis of poly-ß-hydroxy butyrate. However, the present study could provide new insights into the function of Cu ions in ICPs. RESULTS: Bioassay results showed that wild strain BtX023 exhibited high insecticidal activity against Plutella xylostella. The addition of 1 × 10-5 M Cu2+ could considerably increase the expression of cry1Ac and vip3Aa, and the insecticidal activity was enhanced. Quantitative real-time polymerase chain reaction (qRT-PCR) and proteomic analyses revealed that the upregulated proteins included amino acid synthesis, the glyoxylate pathway, oxidative phosphorylation, and poly-ß-hydroxy butyrate synthesis. The Cu ions enhanced energy metabolism and primary amino acid synthesis, will providing abundant raw material accumulation for ICP synthesis. CONCLUSION: The new strain BtX023 exerted a strong insecticidal effect on P. xylostella by producing ICPs. The addition of 1 × 10-5 M Cu2+ in the medium could considerably enhance the expression of the cry1Ac and vip3Aa genes, thereby further increasing the toxicity of BtX023 to Helicoverpa armigera and P. xylostella by enhancing energy synthesis, the glyoxylate cycle, and branched-chain amino acids synthesis, but not poly-ß-hydroxy butyrate synthesis.
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Bacillus thuringiensis , Proteínas de Bactérias/metabolismo , Cátions/farmacologia , Cobre/farmacologia , Inseticidas , Mariposas/efeitos dos fármacos , Animais , Bioensaio , China , Meios de Cultura/química , Metabolismo Energético , Larva/efeitos dos fármacos , ProteômicaRESUMO
Ganglion cells (GCs) are fundamental to retinal neural circuitry, processing photoreceptor signals for transmission to the brain via their axons. However, much remains unknown about their role in vision and their vulnerability to disease leading to blindness. A major bottleneck has been our inability to observe GCs and their degeneration in the living human eye. Despite two decades of development of optical technologies to image cells in the living human retina, GCs remain elusive due to their high optical translucency. Failure of conventional imaging-using predominately singly scattered light-to reveal GCs has led to a focus on multiply-scattered, fluorescence, two-photon, and phase imaging techniques to enhance GC contrast. Here, we show that singly scattered light actually carries substantial information that reveals GC somas, axons, and other retinal neurons and permits their quantitative analysis. We perform morphometry on GC layer somas, including projection of GCs onto photoreceptors and identification of the primary GC subtypes, even beneath nerve fibers. We obtained singly scattered images by: (i) marrying adaptive optics to optical coherence tomography to avoid optical blurring of the eye; (ii) performing 3D subcellular image registration to avoid motion blur; and (iii) using organelle motility inside somas as an intrinsic contrast agent. Moreover, through-focus imaging offers the potential to spatially map individual GCs to underlying amacrine, bipolar, horizontal, photoreceptor, and retinal pigment epithelium cells, thus exposing the anatomical substrate for neural processing of visual information. This imaging modality is also a tool for improving clinical diagnosis and assessing treatment of retinal disease.
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Células Amácrinas/ultraestrutura , Óptica e Fotônica/métodos , Células Bipolares da Retina/ultraestrutura , Células Fotorreceptoras Retinianas Cones/ultraestrutura , Células Ganglionares da Retina/ultraestrutura , Células Horizontais da Retina/ultraestrutura , Tomografia de Coerência Óptica/métodos , Adulto , Células Amácrinas/fisiologia , Contagem de Células , Voluntários Saudáveis , Humanos , Pessoa de Meia-Idade , Fibras Nervosas/fisiologia , Fibras Nervosas/ultraestrutura , Óptica e Fotônica/instrumentação , Células Bipolares da Retina/fisiologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Células Ganglionares da Retina/fisiologia , Células Horizontais da Retina/fisiologia , Tomografia de Coerência Óptica/instrumentação , Visão Ocular/fisiologiaRESUMO
With adaptive optics (AO), optical coherence tomography and scanning laser ophthalmoscopy imaging systems can resolve individual photoreceptor cells in living eyes, due to enhanced lateral spatial resolution. However, no standard test method exists for experimentally quantifying this parameter in ophthalmic AO imagers. Here, we present three-dimensional (3-D) printed phantoms, which enable the measurement of lateral resolution in an anatomically relevant manner. We used two-photon polymerization to fabricate two phantoms, which mimic the mosaic of cone photoreceptor outer segments at multiple retinal eccentricities. With these phantoms, we demonstrated that the resolution of two multimodal AO systems is similar to theoretical predictions, with some intriguing speckle effects.
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Imagem Óptica/instrumentação , Imagens de Fantasmas , Impressão Tridimensional , Células Fotorreceptoras Retinianas Cones/citologia , FótonsRESUMO
Although benzene can be biodegraded when dissolved oxygen is sufficient, delivering oxygen is energy intensive and can lead to air stripping the benzene. Anaerobes can biodegrade benzene by using electron acceptors other than O2 , and this may reduce costs and exposure risks; the drawback is a remarkably slower growth rate. We evaluated a two-step strategy that involved O2 -dependent benzene activation and cleavage followed by intermediate oxidation coupled to NO3- respiration. We employed a membrane biofilm reactor (MBfR) featuring nonporous hollow fibers as the means to deliver O2 directly to a biofilm at an accurately controlled rate. Benzene was mineralized aerobically when the O2 -supply rate was more than sufficient for mineralization. As the O2 -supply capacity was systematically lowered, O2 respiration was gradually replaced by NO3- respiration. When the maximum O2 -supply capacity was only 20% of the demand for benzene mineralization, O2 was used almost exclusively for benzene activation and cleavage, while respiration was almost only by denitrification. Analyses of microbial community structure and predicted metagenomic function reveal that Burkholderiales was dominant and probably utilized monooxygenase activation, with subsequent mineralization coupled to denitrification; strict anaerobes capable of carboxylative activation were not detected. These results open the door for a promising treatment strategy that simultaneously ameliorates technical and economic challenges of aeration and slow kinetics of anaerobic activation of aromatics.
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Benzeno/metabolismo , Nitritos/metabolismo , Oxigênio/metabolismo , Aerobiose , Biofilmes/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Biota , Biotransformação , Burkholderiales/classificação , Burkholderiales/isolamento & purificação , DesnitrificaçãoRESUMO
Adsorption of hexavalent uranium (U(VI)) by extracellular polymeric substances (EPS) has been studied, but the possibility of simultaneous U(VI) reduction mediated by EPS has not had experimental confirmation, as the reduction products have not yet been directly proven. Here, we reported the first direct evidence of lower-valent products of U(VI) immobilization by loosely associated EPS (laEPS) isolated from a fermenter strain of Klebsiella sp. J1 when the laEPS was exposed to H2 . During the 120-min tests for similarly 86% adsorption under O2 , N2 , and H2 , 8% more U was immobilized through a non-adsorptive pathway by the EPS for H2 than for N2 and O2 . A set of solid-state characterization tools (FT-IR, XPS, EELS, and TEM-EDX) confirmed partial reduction of U(VI) to lower-valence U, with the main reduced form being uraninite (UIV O2 ) nanoparticles, and the results reinforced the role of the reduction in accelerating U immobilization and shaping the characteristics of immobilized U in terms of valency, size, and crystallization. The laEPS, mostly comprised of carbohydrate and protein, contained non-cytochrome enzymes and electron carriers that could be responsible for electron transfer to U(VI). Taken together, our results directly confirm that EPS was able to mediate partial U(VI) reduction in the presence of H2 through non-cytochrome catalysis and that reduction enhanced overall U immobilization. Our study fills in some gaps of the microbe-mediated U cycle and will be useful to understand and control U removal in engineered reactors and in-situ bioremediation.
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Matriz Extracelular de Substâncias Poliméricas/metabolismo , Hidrogênio/metabolismo , Klebsiella/metabolismo , Compostos de Urânio/metabolismo , Adsorção , Nanopartículas/metabolismo , Oxirredução , Análise EspectralRESUMO
OBJECTIVE: To explore the variations of subpopulation of peripheral lymphocytes in Parkinson's disease (PD) and locate its potential biomarkers for clinical evaluations. METHODS: The methods of direct immunostaining and flow cytometry were employed to test the percentages of CD3(+), CD3(+)CD4(+), CD3(+)CD8(+), CD19(+) lymphocytes in blood samples of 77 PD patients and 82 healthy controls. And the percentages of CD3(+)CD4(+) and CD3(+)CD8(+) lymphocytes and the parameters of patients and health controls were analyzed. RESULTS: Compared to controls, the percentages of CD3(+), CD3(+)CD4(+) lymphocytes significantly decreased in PD patients ((62 ± 12)% vs (66 ± 9) %, P = 0.04; (35 ± 9) % vs (38 ± 7) %, P = 0.02), especially in males ((66 ± 9)% vs (61 ± 13) %, P = 0.02; (38 ± 10) % vs (33 ± 9) %, P = 0.01)) . Furthermore, the percentage of CD3(+) lymphocytes had a positive correlation with the course of PD in male patients (r = 0.329, P = 0.013, ß = 1.423). And a negative correlation existed between the percentage of CD3(+)CD4(+) lymphocytes and the course of PD and there was a positive correlation with NMSS scale in female PD patients (r = -0.309, P = 0.045, ß = -0.354; r = 0.370, P = 0.020, ß = 0.486). CONCLUSION: The variants in subpopulation of peripheral lymphocytes in PD patients may serve as a potential biomarker for diagnosing PD and predicting its clinical course.
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Linfócitos B , Doença de Parkinson , Feminino , Citometria de Fluxo , Humanos , MasculinoRESUMO
RATIONALE: Small-cell carcinoma of the ovary, hypercalcemic type (SCCOHT), is a rare and aggressive gynecological tumor. We retrospectively analyzed the clinical manifestations and imaging findings of this patient and analyzed the relevant literature, with the aim of improving the ability of radiologists to differentiate SCCOHT from other ovarian tumors. PATIENT CONCERNS: We report a case of 36-year-old woman who was diagnosed with SCCOHT. MRI suggested a malignant tumor of the left ovary. The immunohistochemical markers shows SMARCA4 negativity. Notably, hypercalcemia was not detected. Microscopically, it was consistent with the large-cell variants. LESSIONS: Despite its rarity, SCCOHT should still be considered in the differential diagnosis of ovarian malignancies. When a young female patient presents with a large unilateral tumor on MRI with a predominant solid component and significant enhancement on the contrast enhanced scans, along with hypercalcemia, SCCOHT should be considered.
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Carcinoma de Células Pequenas , Hipercalcemia , Imageamento por Ressonância Magnética , Neoplasias Ovarianas , Humanos , Feminino , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/diagnóstico , Adulto , Hipercalcemia/etiologia , Hipercalcemia/diagnóstico por imagem , Carcinoma de Células Pequenas/diagnóstico por imagem , Carcinoma de Células Pequenas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Diagnóstico DiferencialRESUMO
Impaired retinal blood flow is associated with ocular diseases such as glaucoma, macular degeneration, and diabetic retinopathy. Among several ocular imaging techniques developed to measure retinal blood flow both invasively and non-invasively, adaptive optics (AO)-enabled scanning laser ophthalmoscopy (AO-SLO) resolves individual red blood cells and provides a high resolution with which to measure flow across retinal microvasculature. However, cross-validation of flow measures remains a challenge owing to instrument and patient-specific variability in each imaging technique. Hence, there is a critical need for a well-controlled clinical flow phantom for standardization and to establish blood-flow measures as clinical biomarkers for early diagnosis. Here, we present the design and validation of a simple, compact, portable, linear flow phantom based on a direct current motor and a conveyor-belt system that provides linear velocity tuning within the retinal microvasculature range (0.5-7 mm/s). The model was evaluated using a sensitive AO-SLO line-scan technique, which showed a <6% standard deviation from the true velocity. Further, a clinical SLO instrument showed a linear correlation with the phantom's true velocity (r2 > 0.997). This model has great potential to calibrate, evaluate, and improve the accuracy of existing clinical imaging systems for retinal blood flow and aid in the diagnosis of ocular diseases with abnormal blood flow.
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Photoreceptors (PRs) and retinal pigment epithelial (RPE) cells form a functional unit called the PR-RPE complex. The PR-RPE complex plays a critical role in maintaining retinal homeostasis and function, and the quantification of its structure and topographical arrangement across the macula are important for understanding the etiology, mechanisms, and progression of many retinal diseases. However, the three-dimensional cellular morphology of the PR-RPE complex in living human eyes has not been completely described due to limitations in imaging techniques. We used the cellular resolution and depth-sectioning capabilities of a custom, high-speed Fourier domain mode-locked laser-based adaptive optics-optical coherence tomography (FDML-AO-OCT) platform to characterize human PR-RPE complex topography across the temporal macula from eleven healthy volunteers. With the aid of a deep learning algorithm, key metrics were extracted from the PR-RPE complex of averaged AO-OCT volumes including PR and RPE cell density, PR outer segment length (OSL), and PR/RPE ratio. We found a tight grouping among our cohort for PR density, with a mean (±SD) value of 53,329 (±8106) cells/mm2 at 1° decreasing to 8669 (±737) cells/mm2 at 12°. We observed a power function relationship between eccentricity and both PR density and PR/RPE ratio. We found similar variability in our RPE density measures, with a mean value of 7335 (±681) cells/mm2 at 1° decreasing to 5547 (±356) cells/mm2 at 12°, exhibiting a linear relationship with a negative slope of -123 cells/mm2 per degree. OSL monotonically decreased from 33.3 (±2.4) µm at 1° to 18.0 (±1.8) µm at 12°, following a second-order polynomial relationship. PR/RPE ratio decreased from 7.3 (±0.9) µm at 1° to 1.5 (±0.1) µm at 12°. The normative data from this investigation will help lay a foundation for future studies of retinal pathology.
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BACKGROUND: In vivo imaging of the human retina using adaptive optics optical coherence tomography (AO-OCT) has transformed medical imaging by enabling visualization of 3D retinal structures at cellular-scale resolution, including the retinal pigment epithelial (RPE) cells, which are essential for maintaining visual function. However, because noise inherent to the imaging process (e.g., speckle) makes it difficult to visualize RPE cells from a single volume acquisition, a large number of 3D volumes are typically averaged to improve contrast, substantially increasing the acquisition duration and reducing the overall imaging throughput. METHODS: Here, we introduce parallel discriminator generative adversarial network (P-GAN), an artificial intelligence (AI) method designed to recover speckle-obscured cellular features from a single AO-OCT volume, circumventing the need for acquiring a large number of volumes for averaging. The combination of two parallel discriminators in P-GAN provides additional feedback to the generator to more faithfully recover both local and global cellular structures. Imaging data from 8 eyes of 7 participants were used in this study. RESULTS: We show that P-GAN not only improves RPE cell contrast by 3.5-fold, but also improves the end-to-end time required to visualize RPE cells by 99-fold, thereby enabling large-scale imaging of cells in the living human eye. RPE cell spacing measured across a large set of AI recovered images from 3 participants were in agreement with expected normative ranges. CONCLUSIONS: The results demonstrate the potential of AI assisted imaging in overcoming a key limitation of RPE imaging and making it more accessible in a routine clinical setting.
The retinal pigment epithelium (RPE) is a single layer of cells within the eye that is crucial for vision. These cells are unhealthy in many eye diseases, and this can result in vision problems, including blindness. Imaging RPE cells in living human eyes is time consuming and difficult with the current technology. Our method substantially speeds up the process of RPE imaging by incorporating artificial intelligence. This enables larger areas of the eye to be imaged more efficiently. Our method could potentially be used in the future during routine eye tests. This could lead to earlier detection and treatment of eye diseases, and the prevention of some causes of blindness.
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The effective monitoring of microalgae cultivation is crucial for optimizing their energy utilization efficiency. In this paper, a quantitative analysis method, using microalgae images based on two convolutional neural networks, EfficientNet (EFF) and residual network (RES), is proposed. Suspension samples prepared from two types of dried microalgae powders, Rhodophyta (RH) and Spirulina (SP), were used to mimic real microalgae cultivation settings. The method's prediction accuracy of the algae concentration ranges from 0.94 to 0.99. RH, with a distinctively pronounced red-green-blue value shift, achieves a higher prediction accuracy than SP. The prediction results of the two algorithms were significantly superior to those of a linear regression. Additionally, RES outperforms EFF in terms of its generalization ability and robustness, which is attributable to its distinct residual block architecture. The RES provides a viable approach for the image-based quantitative analysis.
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Biomassa , Microalgas , Redes Neurais de Computação , Spirulina , Microalgas/metabolismo , Spirulina/metabolismo , Rodófitas/metabolismo , Processamento de Imagem Assistida por Computador/métodos , AlgoritmosRESUMO
In this study, a micro-nano TaC ceramic steel matrix reinforced layer was prepared by an in situ reaction between a pure tantalum plate and GCr15 steel. The microstructure and phase structure of the in situ reaction reinforced layer of the sample at 1100 °C and reaction time 1 h were characterized with FIB micro-section, TEM transmission, SAED diffraction pattern, SEM and EBSD. The phase composition, phase distribution, grain size, grain orientation and grain boundary deflection, phase structure and lattice constant of the sample were characterized in detail. The results show that the phase composition of the Ta sample is Ta, TaC, Ta2C and α-Fe. TaC is formed after Ta and carbon atoms meet, and the orientation changes in the X and Z directions. The grain size of TaC is widely in the range of 0~0.4 µm, and the angular deflection of TaC grain is not obvious. The high-resolution transmission structure, diffraction pattern and interplanar spacing of the phase were characterized, and the crystal planes of different crystal belt axes were determined. The study provides technical and theoretical support for further research on the preparation technology and microstructure of the TaC ceramic steel matrix reinforcement layer.
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Purpose: To apply adaptive optics-optical coherence tomography (AO-OCT) to quantify multiple sclerosis (MS)-induced changes in axonal bundles in the macular nerve fiber layer, ganglion cell somas, and macrophage-like cells at the vitreomacular interface. Methods: We used AO-OCT imaging in a pilot study of MS participants (n = 10), including those without and with a history of optic neuritis (ON, n = 4), and healthy volunteers (HV, n = 9) to reveal pathologic changes to inner retinal cells and structures affected by MS. Results: We found that nerve fiber layer axonal bundles had 38% lower volume in MS participants (1.5 × 10-3 mm3) compared to HVs (2.4 × 10-3 mm3; P < 0.001). Retinal ganglion cell (RGC) density was 51% lower in MS participants (12.3 cells/mm2 × 1000) compared to HVs (25.0 cells/mm2 × 1000; P < 0.001). Spatial differences across the macula were observed in RGC density. RGC diameter was 15% higher in MS participants (11.7 µm) compared to HVs (10.1 µm; P < 0.001). A nonsignificant trend of higher density of macrophage-like cells in MS eyes was also observed. For all AO-OCT measures, outcomes were worse for MS participants with a history of ON compared to MS participants without a history of ON. AO-OCT measures were associated with key visual and physical disabilities in the MS cohort. Conclusions: Our findings demonstrate the utility of AO-OCT for highly sensitive and specific detection of neurodegenerative changes in MS. Moreover, the results shed light on the mechanisms that underpin specific neuronal pathology that occurs when MS attacks the retina. The new findings support the further development of AO-based biomarkers for MS.