Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 133
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Nature ; 605(7910): 457-463, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35585341

RESUMEN

Microcombs have sparked a surge of applications over the past decade, ranging from optical communications to metrology1-4. Despite their diverse deployment, most microcomb-based systems rely on a large amount of bulky elements and equipment to fulfil their desired functions, which is complicated, expensive and power consuming. By contrast, foundry-based silicon photonics (SiPh) has had remarkable success in providing versatile functionality in a scalable and low-cost manner5-7, but its available chip-based light sources lack the capacity for parallelization, which limits the scope of SiPh applications. Here we combine these two technologies by using a power-efficient and operationally simple aluminium-gallium-arsenide-on-insulator microcomb source to drive complementary metal-oxide-semiconductor SiPh engines. We present two important chip-scale photonic systems for optical data transmission and microwave photonics, respectively. A microcomb-based integrated photonic data link is demonstrated, based on a pulse-amplitude four-level modulation scheme with a two-terabit-per-second aggregate rate, and a highly reconfigurable microwave photonic filter with a high level of integration is constructed using a time-stretch approach. Such synergy of a microcomb and SiPh integrated components is an essential step towards the next generation of fully integrated photonic systems.

2.
Brief Bioinform ; 25(3)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38701420

RESUMEN

The relationship between genotype and fitness is fundamental to evolution, but quantitatively mapping genotypes to fitness has remained challenging. We propose the Phenotypic-Embedding theorem (P-E theorem) that bridges genotype-phenotype through an encoder-decoder deep learning framework. Inspired by this, we proposed a more general first principle for correlating genotype-phenotype, and the P-E theorem provides a computable basis for the application of first principle. As an application example of the P-E theorem, we developed the Co-attention based Transformer model to bridge Genotype and Fitness model, a Transformer-based pre-train foundation model with downstream supervised fine-tuning that can accurately simulate the neutral evolution of viruses and predict immune escape mutations. Accordingly, following the calculation path of the P-E theorem, we accurately obtained the basic reproduction number (${R}_0$) of SARS-CoV-2 from first principles, quantitatively linked immune escape to viral fitness and plotted the genotype-fitness landscape. The theoretical system we established provides a general and interpretable method to construct genotype-phenotype landscapes, providing a new paradigm for studying theoretical and computational biology.


Asunto(s)
COVID-19 , Aprendizaje Profundo , Genotipo , Fenotipo , SARS-CoV-2 , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Humanos , COVID-19/virología , COVID-19/genética , COVID-19/inmunología , Biología Computacional/métodos , Algoritmos , Aptitud Genética
3.
Semin Cancer Biol ; 101: 58-73, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38810814

RESUMEN

Cancer is daunting pathology with remarkable breadth and scope, spanning genetics, epigenetics, proteomics, metalobomics and cell biology. Cellular senescence represents a stress-induced and essentially irreversible cell fate associated with aging and various age-related diseases, including malignancies. Senescent cells are characterized of morphologic alterations and metabolic reprogramming, and develop a highly active secretome termed as the senescence-associated secretory phenotype (SASP). Since the first discovery, senescence has been understood as an important barrier to tumor progression, as its induction in pre-neoplastic cells limits carcinogenesis. Paradoxically, senescent cells arising in the tumor microenvironment (TME) contribute to tumor progression, including augmented therapeutic resistance. In this article, we define typical forms of senescent cells commonly observed within the TME and how senescent cells functionally remodel their surrounding niche, affect immune responses and promote cancer evolution. Furthermore, we highlight the recently emerging pipelines of senotherapies particularly senolytics, which can selectively deplete senescent cells from affected organs in vivo and impede tumor progression by restoring therapeutic responses and securing anticancer efficacies. Together, co-targeting cancer cells and their normal but senescent counterparts in the TME holds the potential to achieve increased therapeutic benefits and restrained disease relapse in future clinical oncology.


Asunto(s)
Senescencia Celular , Neoplasias , Microambiente Tumoral , Humanos , Microambiente Tumoral/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Neoplasias/metabolismo , Senescencia Celular/efectos de los fármacos , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Fenotipo Secretor Asociado a la Senescencia , Senoterapéuticos/farmacología
4.
Immunity ; 43(6): 1137-47, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26680206

RESUMEN

Atherosclerosis is a chronic inflammatory disease of arterial wall. Mitochondrial DNA (mtDNA) and human antimicrobial peptide LL-37 (Cramp in mice) are involved in atherosclerosis. Recently, mtDNA has been found to escape from autophagy and cause inflammation. Normally, mtDNA as an inflammatogenic factor cannot escape from autophagy and degradation by DNase II. In this study, we found elevated amounts of LL37-mtDNA complex in atherosclerotic plasma and plaques. The complex was resistant to DNase II degradation and escaped from autophagic recognition, leading to activation of Toll-like receptor 9 (TLR9)-mediated inflammatory responses. Mouse model studies indicated that Cramp-mtDNA complex aggravated atherosclerotic lesion formation in apolipoprotein E-deficient mice and antibody treatment against the complex alleviated the lesion. These findings suggest that the LL-37-mtDNA complex acts as a key mediator of atherosclerosis formation, and thus represents a promising therapeutic target.


Asunto(s)
Aterosclerosis/metabolismo , Autofagia/fisiología , Catelicidinas/metabolismo , ADN Mitocondrial/metabolismo , Placa Aterosclerótica/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Péptidos Catiónicos Antimicrobianos , Aterosclerosis/patología , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Placa Aterosclerótica/patología
5.
Org Biomol Chem ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38869074

RESUMEN

The hydroboration and hydrosilylation of alkenes catalyzed by the unsymmetrical ß-diketiminate magnesium methyl complex [(DippXylNacnac)MgMe (THF)] (1) have been reported. When complex 1 was employed as a highly efficient catalyst in the hydroboration of various alkenes with HBpin, only the anti-Markovnikov hydroboration products were obtained in high yields and with high regioselectivities under mild reaction conditions (60 °C). To our surprise, it showed different regioselectivities in the hydrosilylation of a range of alkenes with PhSiH3. Aromatic alkene substrates afforded the corresponding branched Markovnikov hydrosilylation products in high yields and with high regioselectivities; conversely, aliphatic alkenes produced the linear anti-Markovnikov products in moderate yields. This is completely consistent with the corresponding density functional theory (DFT) calculations. In addition, the practical utility was demonstrated via scale-up reactions of boronate esters and a preliminary plausible mechanism of hydroboration and hydrosilylation have been investigated as well.

6.
BMC Pulm Med ; 24(1): 207, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671448

RESUMEN

OBJECTIVE: The aim of this research was to examine how penehyclidine hydrochloride (PHC) impacts the occurrence of pyroptosis in lung tissue cells within a rat model of lung ischemia-reperfusion injury. METHODS: Twenty-four Sprague Dawley (SD) rats, weighing 250 g to 270 g, were randomly distributed into three distinct groups as outlined below: a sham operation group (S group), a control group (C group), and a test group (PHC group). Rats in the PHC group received a preliminary intravenous injection of PHC at a dose of 3 mg/kg. At the conclusion of the experiment, lung tissue and blood samples were collected and properly stored for subsequent analysis. The levels of malondialdehyde, superoxide dismutase, and myeloperoxidase in the lung tissue, as well as IL-18 and IL-1ß in the blood serum, were assessed using an Elisa kit. Pyroptosis-related proteins, including Caspase1 p20, GSDMD-N, and NLRP3, were detected through the western blot method. Additionally, the dry-to-wet ratio (D/W) of the lung tissue and the findings from the blood gas analysis were also documented. RESULTS: In contrast to the control group, the PHC group showed enhancements in oxygenation metrics, reductions in oxidative stress and inflammatory reactions, and a decrease in lung injury. Additionally, the PHC group exhibited lowered levels of pyroptosis-associated proteins, including the N-terminal segment of gasdermin D (GSDMD-N), caspase-1p20, and nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3). CONCLUSION: Pre-administration of PHC has the potential to mitigate lung ischemia-reperfusion injuries by suppressing the pyroptosis of lung tissue cells, diminishing inflammatory reactions, and enhancing lung function. The primary mechanism behind anti-pyroptotic effect of PHC appears to involve the inhibition of oxidative stress.


Asunto(s)
Gasderminas , Pulmón , Piroptosis , Quinuclidinas , Ratas Sprague-Dawley , Daño por Reperfusión , Animales , Piroptosis/efectos de los fármacos , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/prevención & control , Ratas , Quinuclidinas/farmacología , Pulmón/efectos de los fármacos , Pulmón/patología , Pulmón/metabolismo , Masculino , Malondialdehído/metabolismo , Modelos Animales de Enfermedad , Interleucina-1beta/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Interleucina-18/metabolismo , Proteínas de Unión a Fosfato/metabolismo , Superóxido Dismutasa/metabolismo , Peroxidasa/metabolismo , Estrés Oxidativo/efectos de los fármacos , Caspasa 1/metabolismo , Lesión Pulmonar/tratamiento farmacológico , Lesión Pulmonar/metabolismo
7.
Molecules ; 29(8)2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38675630

RESUMEN

AHP-3a, a triple-helix acidic polysaccharide isolated from Alpinia officinarum Hance, was evaluated for its anticancer and antioxidant activities. The physicochemical properties and structure of AHP-3a were investigated through gel permeation chromatography, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. The weight-average molecular weight of AHP-3a was 484 kDa, with the molar percentages of GalA, Gal, Ara, Xyl, Rha, Glc, GlcA, and Fuc being 35.4%, 21.4%, 16.9%, 11.8%, 8.9%, 3.1%, 2.0%, and 0.5%, respectively. Based on the results of the monosaccharide composition analysis, methylation analysis, and NMR spectroscopy, the main chain of AHP-3a was presumed to consist of (1→4)-α-D-GalpA and (1→2)-α-L-Rhap residues, which is a pectic polysaccharide with homogalacturonan (HG) and rhamnogalacturonan-I (RG-I) structural domains containing side chains. In addition, the results of the antioxidant activity assay revealed that the ability of AHP-3a to scavenge DPPH, ABTS, and OH free radicals increased with an increase in its concentration. Moreover, according to the results from the EdU, wound healing, and Transwell assays, AHP-3a can control the proliferation, migration, and invasion of HepG2 and Huh7 hepatocellular carcinoma cells without causing any damage to healthy cells. Thus, AHP-3a may be a natural antioxidant and anticancer component.


Asunto(s)
Alpinia , Antioxidantes , Compuestos de Bifenilo , Polisacáridos , Alpinia/química , Polisacáridos/química , Polisacáridos/farmacología , Polisacáridos/aislamiento & purificación , Humanos , Antioxidantes/farmacología , Antioxidantes/química , Proliferación Celular/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Células Hep G2 , Peso Molecular , Línea Celular Tumoral , Monosacáridos/análisis , Monosacáridos/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Picratos/química , Picratos/antagonistas & inhibidores , Espectroscopía Infrarroja por Transformada de Fourier
8.
J Environ Sci (China) ; 142: 11-20, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38527877

RESUMEN

Chromium released during municipal solid waste incineration (MSWI) is toxic and carcinogenic. The removal of chromium from simulated MSWI flue gas by four sorbents (CaO, bamboo charcoal (BC), powdered activated carbon (PAC), and Al2O3) and the effects of four oxides (SiO2, Al2O3, Fe2O3, and CaO) on chromium speciation transformation were investigated. The results showed that the removal rates of total Cr by the four sorbents were Al2O3 < CaO < PAC < BC, while the removal rates of Cr(VI) by the four sorbents were Al2O3 < PAC < BC < CaO. CaO had a strong oxidizing effect on Cr(III), while BC and PAC had a better-reducing effect on Cr(VI). SiO2 was better for the reduction of Na2CrO4 and K2CrO4 above 1000°C due to its strong acidity, and the addition of CaO significantly inhibited the reduction of Cr(VI). MgCrO4 decomposed above 700°C to form MgCr2O4, and the reaction between MgCrO4 and oxides also existed in the form of a more stable trivalent spinel. Furthermore, when investigating the effect of oxides on the oxidation of Cr(III) in CrCl3, it was discovered that CaO promoted the conversion of Cr(III) to Cr(VI), while the presence of chlorine caused chromium to exist in the form of Cr(V), and increasing the content of CaO and extending the heating time facilitated the oxidation of Cr(III). In addition, silicate, aluminate, and ferrite were generated after the addition of SiO2, Al2O3, and Fe2O3, which reduced the alkalinity of CaO and had an important role in inhibiting the oxidation of Cr(III). The acidic oxides can not only promote the reduction of Cr(VI) but also have an inhibitory effect on the oxidation of Cr(III) ascribed to alkali metals/alkaline earth metals, and the proportion of acidic oxides can be increased moderately to reduce the generation of harmful substances in the hazardous solid waste heat treatment.


Asunto(s)
Óxidos , Residuos Sólidos , Dióxido de Silicio , Cromo/análisis , Oxidación-Reducción , Incineración
9.
Opt Express ; 31(12): 19126-19132, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37381336

RESUMEN

In this paper, a continuous-wave Nd:YAG InnoSlab laser at 1319 nm with high output power and high beam quality is demonstrated. The maximum output power of 170 W at 1319-nm single wavelength is obtained with an optical-to-optical efficiency of 15.3% from absorbed pump power to laser output and the corresponding slope efficiency of 26.7%. The beam quality factors of M2 are 1.54 and 1.78 in the horizontal and vertical directions, respectively. To the best of our knowledge, this is the first report on Nd:YAG 1319-nm InnoSlab lasers with such high output power and good beam quality.

10.
Opt Express ; 31(16): 26757-26763, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37710527

RESUMEN

A single-frequency quasi-continuous-wave partially end-pumped slab (Innoslab) laser amplifier at 1319 nm was demonstrated. The 3-W single-frequency all-fiber seed laser was amplified to a maximum average power of 80.1 W and the power stability was 0.52% in 10 minutes. The corresponding optical-optical efficiency was 16.1% under absorbed pump power of 478 W. The output pulse width was 131 µs at the repetition of 500 Hz. The beam quality factors of M2 were 1.3 in both the vertical and horizontal directions. To the best of our knowledge, this is the first report on single-frequency Nd:YAG Innoslab amplifier at 1319 nm with such high output power and efficiency.

11.
Chemistry ; 29(31): e202300407, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37032546

RESUMEN

Lithium-sulfur batteries (LSBs) have been considered as one of the most promising energy storage systems owing to their high theoretical energy density and abundant sulfuric resources. However, their commercial application is limited by rapid capacity decline and low Coulombic efficiency. Metal-organic frameworks (MOFs) made of metallic nodes and organic ligands can suppress polysulfide shuttling and promote redox kinetics. In this paper, the effects of crystallographic dimensions and metallic categories on chemical performance of LSBs have been meticulously explored electrochemical performance. As a result, exposed Ni active sites in a lamellar Ni-MOF was found to deliver a superior electrochemical performance. The as-assembled LSBs with 2D-Ni-MOF/CNTs cathode deliver a much superior initial discharge capacity, (820 mAh g-1 at 0.5 C), and exhibit excellent cycling stability over 550 cycles than those analogues of 3D stereoscopic Ni-MOF and 2D lamellar Co-MOF. This work proposed a perspective in elevating LSBs performance through synergistic optimization of the MOFs dimensions and the metallic nuclei in the cathodes.

12.
Org Biomol Chem ; 21(17): 3628-3635, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37066692

RESUMEN

Alkaline-earth metals have attracted increasing attention because they are cheap, Earth abundant and environmentally friendly, and have gradually become inexpensive and sustainable alternatives to traditional precious transition metal catalysts in many organic reactions. Recently, the hydroboration of unsaturated organic substrates has been extensively investigated. However, reports on alkaline-earth metal catalyzed hydroboration of isocyanates and ketones are rare. Herein, we report that simple, commercially available, and air-stable magnesium halides have been successfully employed as highly efficient catalysts in the hydroboration of isocyanates and ketones. Various boronate products were obtained in high yields with low catalyst loading under mild conditions.

13.
Eur J Nutr ; 62(4): 1599-1610, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36717385

RESUMEN

PURPOSE: To test the hypothesis that daily supplementation with low-dose B vitamins plus betaine could significantly reduce plasma homocysteine concentrations in Chinese adults with hyperhomocysteinemia and free from background mandatory folic acid fortification. METHODS: One hundred apparently healthy adults aged 18-65 years with hyperhomocysteinemia were recruited in South China from July 2019 to June 2021. They were randomly assigned to either the supplement group (daily supplementation: 400 µg folic acid, 8 mg vitamin B6, 6.4 µg vitamin B12 and 1 g betaine) or the placebo group for 12 weeks. Fasting venous blood was collected at baseline, week 4 and week 12 to determine the concentrations of homocysteine, folate, vitamin B12 and betaine. Generalized estimation equations were used for statistical analysis. RESULTS: Statistically significant increments in blood concentrations of folate, vitamin B12 and betaine after the intervention in the supplement group indicated good participant compliance. At baseline, there were no significant differences in plasma homocysteine concentration between the two groups (P = 0.265). After 12-week supplementation, compared with the placebo group, there was a significant reduction in plasma homocysteine concentrations in the supplement group (mean group difference - 3.87; covariate-adjusted P = 0.012; reduction rate 10.1%; covariate-adjusted P < 0.001). In the supplement group, the decreased concentration of plasma homocysteine was associated with increments of blood concentrations of both folate (ß = -1.680, P = 0.004) and betaine (ß = -1.421, P = 0.020) after 12 weeks of supplementation. CONCLUSIONS: Daily supplementation with low-dose B vitamins plus betaine for 12 weeks effectively decreased plasma homocysteine concentrations in Chinese adults with hyperhomocysteinemia. TRIAL REGISTRATION: This trial was registered at clinicaltrials.gov as NCT03720249 on October 25, 2018. Website: https://clinicaltrials.gov/ct2/show/NCT03720249 .


Asunto(s)
Hiperhomocisteinemia , Complejo Vitamínico B , Adulto , Humanos , Betaína , Suplementos Dietéticos , Método Doble Ciego , Pueblos del Este de Asia , Ácido Fólico , Homocisteína , Vitamina B 12 , Adolescente , Adulto Joven , Persona de Mediana Edad , Anciano
14.
Nutr Neurosci ; 26(5): 445-455, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35385370

RESUMEN

Brain aging is a complex biological process often associated with a decline in cognitive functions and motility. Astaxanthin (AST) is a strong antioxidant capable of crossing the blood-brain barrier. The effect of AST on brain aging and its physiological and molecular mechanism are still unclear. The study aimed to investigate whether AST from AstaReal A1010 improved brain aging by inducing autophagy in SAMP10 mice. Different concentrations of AstaReal A1010 were intragastrically administered to 6-month-old SAMP10 mice for 3 months. The results demonstrated that AST delayed age-related cognitive decline, motor ability and neurodegeneration, upregulated the expression levels of autophagy-related genes beclin-1 and LC3 in the brain. It may induce autophagy by regulating IGF-1/Akt/mTOR and IGF-1/Akt/FoxO3a signaling. Treatment with autophagy inhibitor 3-methyladenine (3MA) partly reversed the anti-aging effect of AST. In conclusion, our findings suggest that AST may induce autophagy by regulating IGF-1/Akt/mTOR and IGF-1/Akt/FoxO3a signaling, thereby delaying age-related neurodegeneration and cognitive decline in SAMP10 mice.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina , Proteínas Proto-Oncogénicas c-akt , Ratones , Animales , Factor I del Crecimiento Similar a la Insulina/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Envejecimiento/fisiología , Encéfalo/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/farmacología , Autofagia
15.
Biosci Biotechnol Biochem ; 87(7): 724-735, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37188634

RESUMEN

The collagen had been widely used as a promising source of functional food supplements for skin care. Here, we developed a novel animal-derived collagen that displayed multiple functions for protecting the human skin cells under UV irradiation. Different evaluations were performed to explore the protective effects of this collagen on human skin fibroblasts and keratinocytes. Specifically, we found that our collagen could induce the production of collagen I, elastin, and hyaluronic acid in fibroblasts and could also enhance the skin wound healing ability. Besides, it could elevate the expression of aquaporin-3 and cluster of differentiation 44 in keratinocytes. Moreover, this collagen had been demonstrated to alleviate the generation of reactive oxygen species and the malondialdehyde content in UVA-treated fibroblasts, as well as the secretion of inflammation factors in keratinocytes. These data indicated that the novel animal-derived collagen was a hopeful material for the comprehensive protection of the skin cells and the prevention of skin aging.


Asunto(s)
Queratinocitos , Piel , Animales , Humanos , Queratinocitos/metabolismo , Colágeno/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Rayos Ultravioleta/efectos adversos , Fibroblastos
16.
J Dairy Sci ; 106(8): 5253-5265, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37414601

RESUMEN

Whey protein powder (PP), which is mainly derived from bovine milk, is rich in milk fat globule membrane (MFGM). The MGFM has been shown to play a role in promoting neuronal development and cognition in the infant brain. However, its role in Alzheimer's disease (AD) has not been elucidated. Here, we showed that the cognitive ability of 3×Tg-AD mice (a triple-transgenic mouse model of AD) could be improved by feeding PP to mice for 3 mo. In addition, PP ameliorated amyloid peptide deposition and tau hyperphosphorylation in the brains of AD mice. We found that PP could alleviate AD pathology by inhibiting neuroinflammation through the peroxisome proliferator-activated receptor γ (PPARγ)-nuclear factor-κB signaling pathway in the brains of AD mice. Our study revealed an unexpected role of PP in regulating the neuroinflammatory pathology of AD in a mouse model.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Ratones , Animales , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/psicología , Enfermedad de Alzheimer/veterinaria , PPAR gamma , Proteína de Suero de Leche , Polvos , Enfermedades Neuroinflamatorias/veterinaria , Proteínas tau/metabolismo , Ratones Transgénicos , Transducción de Señal , Modelos Animales de Enfermedad
17.
Sensors (Basel) ; 23(14)2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37514610

RESUMEN

Compared to wide-field telescopes, small-field detection systems have higher spatial resolution, resulting in stronger detection capabilities and higher positioning accuracy. When detecting by small fields in synchronous orbit, both space debris and fixed stars are imaged as point targets, making it difficult to distinguish them. In addition, with the improvement in detection capabilities, the number of stars in the background rapidly increases, which puts higher requirements on recognition algorithms. Therefore, star detection is indispensable for identifying and locating space debris in complex backgrounds. To address these difficulties, this paper proposes a real-time star extraction method based on adaptive filtering and multi-frame projection. We use bad point repair and background suppression algorithms to preprocess star images. Afterwards, we analyze and enhance the target signal-to-noise ratio (SNR). Then, we use multi-frame projection to fuse information. Subsequently, adaptive filtering, adaptive morphology, and adaptive median filtering algorithms are proposed to detect trajectories. Finally, the projection is released to locate the target. Our recognition algorithm has been verified by real star images, and the images were captured using small-field telescopes. The experimental results demonstrate the effectiveness of the algorithm proposed in this paper. We successfully extracted hip-27066 star, which has a magnitude of about 12 and an SNR of about 1.5. Compared with existing methods, our algorithm has advantages in both recognition rate and false-alarm rate, and can be used as a real-time target recognition algorithm for space-based synchronous orbit detection payloads.

18.
J Cell Mol Med ; 26(9): 2698-2705, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35384323

RESUMEN

Nicotinamide adenine dinucleotide (NAD+ ) level is the protective factor of cardiovascular diseases (CVDs). In addition, anaemia is a risk factor of adverse cardiovascular outcomes in women. However, there are limited data about the association between NAD+ and anaemia. The aim of this study was to evaluate association of NAD+ with anaemia among women. A total of 727 females from Jidong community were included in the current analysis. NAD+ levels were tested by the cycling assay and HPLC assay using whole blood samples. Anaemia was determined by haemoglobin (Hb) concentration, and the subtypes of anaemia were further defined according to mean corpuscular volume (MCV) in blood. Multivariable logistic analysis was used to analyse the association between NAD+ levels and anaemia or its subtypes. The mean age of recruited subjects was 42.7 years. The proportion of anaemia by NAD+ levels quartiles were 19.7% (35/178), 4.8% (9/189), 3.4% (6/178) and 2.7% (5/182). Haematological parameters including haemoglobin (Hb), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC) and red blood count (RBC) increased over NAD+ quartiles. Red cell volume distribution width (RDW) decreased over NAD+ quartiles. Compared with the lowest quartile of NAD+ levels (<27.6µM), the adjusted odds ratios with 95% confidence intervals of the top quartile were 0.15 (0.06-0.41) for anaemia, 0.05 (0.01-0.36) for microcytic anaemia and 0.37 (0.10-1.36) for normocytic anaemia respectively. Higher NAD+ levels were significantly associated with lower prevalence of anaemia among women, especially microcytic anaemia and normocytic anaemia. Haematological parameters might serve as a predictor of the blood NAD+ levels.


Asunto(s)
Anemia , NAD , Adulto , Anemia/epidemiología , Anemia Hipocrómica , Índices de Eritrocitos , Femenino , Hemoglobinas , Humanos
19.
Heart Surg Forum ; 25(1): E155-E162, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35238293

RESUMEN

Interrupted aortic arch (IAA) is a rare congenital anomaly of the aortic arch and an anatomical interruption of the lumen between the ascending and descending aorta. Computed tomography (CT) has become a reliable noninvasive diagnostic method for congenital IAA. The purpose of this study was to investigate the imaging features of IAA and improve the understanding and diagnosis of the disease. The imaging features and postoperative pathological data of 25 patients with IAA confirmed by dual-source computed tomography (DSCT) angiography were analyzed in this retrospective study. Among the 25 patients with IAA, 15 were type A, seven were type B, 0 were types C and D, and two were type E. The diameter of the pulmonary artery trunk in type A was larger than that in type B (P < 0.05). However, there were no significant differences between types A and B along the ascending aorta diameter, descending aorta, ascending aorta/descending aorta ratio, left pulmonary artery main trunk diameter, right pulmonary artery main trunk diameter, left pulmonary artery trunk/pulmonary artery trunk ratio, right pulmonary artery trunk/pulmonary artery trunk ratio, and left pulmonary artery trunk/right pulmonary artery trunk ratio. The imaging findings of IAA have typical and specific signs, and the types of IAA are not comprehensive. One type of patient identification can be added: Patients who are dissected between the left common carotid artery and left subclavian artery opening, and the descending aorta is circulated by the chest collaterals. Patients with a wide pulmonary artery in the IAA are usually type A patients. Patients with IAA after surgical repair require lifetime follow up, mainly to monitor left ventricular outflow tract obstruction and recurrent aortic coarctation. This study was approved by the Ethics Committee of Kunming Yan'an Hospital (Kunming City, Yunnan Province, China), and consent was waived because of the retrospective data collection.


Asunto(s)
Coartación Aórtica , Cardiopatías Congénitas , Aorta Torácica/cirugía , Coartación Aórtica/cirugía , China , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/cirugía , Humanos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
20.
Environ Microbiol ; 23(3): 1750-1764, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33684236

RESUMEN

Infants often experience complementary food-induced diarrhoea (CFID), which occurs when infants switch from breast milk to solid foods. The relative abundances of Prevotella and Rothia were higher in stools of infants with CFID, while the relative abundances of Enterococcus and Escherichia were higher in healthy infants. The abundance of Lactobacillus spp. normally found in breast milk fed to infants with CFID was significantly reduced, and Enterococcus spp. were less abundant when diarrhoea occurred. Furthermore, Lactobacillus and Enterococcus were present as shared bacteria in both mother and infant, and they were considered potential anti-CFID probiotics as their relative abundances in breast milk were negatively correlated to infant CFID. Kyoto encyclopedia of genes and genomes (KEGG) functional analysis showed that the function of amino acid metabolism differed between infants with CFID and healthy infants. Therefore, CFID might be related to the decomposition of proteins in food supplements. The screening revealed seven hydrolytic casein and five hydrolytic casein and rice protein isolates from 320 suspected Lactobacillus and Enterococcus isolates. The animal experiments demonstrated that a mixture of five isolates effectively hydrolysed the casein and rice protein and prevented diarrhoea in young rats. Thus, the occurrence of CFID was found to be closely related to the intestinal and breast milk microbiota, and bacteria that could assist in the digestion of cereal proteins were involved in CFID.


Asunto(s)
Microbiota , Probióticos , Animales , Lactancia Materna , Heces , Femenino , Humanos , Lactobacillus , Leche Humana , Ratas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA