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1.
Mar Environ Res ; 190: 106082, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37429213

RESUMO

Revealing the ecological processes and environmental adaptation of abundant and rare archaea is a central, but poorly understood, topic in ecology. Here, abundant and rare archaeal diversity, community assembly processes and co-occurrence patterns were comparatively analyzed in Arctic marine sediments. Our findings revealed that the rare taxa exhibited significantly higher diversity compared to the abundant taxa. Additionally, the abundant taxa displayed stronger environmental adaptation than the rare taxa. The co-occurrence network analysis demonstrated that the rare taxa developed more interspecies interactions and modules in response to environmental disturbance. Furthermore, the community assembly of abundant and rare taxa in sediments was primarily controlled by stochastic and deterministic processes, respectively. These findings provide valuable insights into the archaeal community assembly processes and significantly contribute to a deeper understanding of the environmental adaptability of abundant and rare taxa in Arctic marine sediments.


Assuntos
Archaea , Sedimentos Geológicos , Archaea/genética , Regiões Árticas
2.
Cell Mol Neurobiol ; 43(5): 1989-2004, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36030297

RESUMO

Acute ischemic stroke (AIS) is a serious threat to human health. Following AIS, cerebral ischemia-reperfusion injury (CIRI) must be treated to improve prognosis. By combining 4D label-free quantitative proteomics with lactylation modification-specific proteomics analysis, we assessed lysine lactylation (Kla) in cortical proteins of a CIRI rat model. We identified a total of 1003 lactylation sites on 469 proteins in this study, gathering quantitative information (PXD034232) on 660 of 310 proteins, which were further classified by cell composition, molecular function, and biological processes. In addition, we analyzed the metabolic pathways, domains, and protein-protein interaction networks. Lastly, we evaluated differentially expressed lysine lactylation sites, determining 49 upregulated proteins and 99 downregulated proteins with 54 upregulated sites and 54 downregulated sites in the experimental group in comparison with the healthy control group. Moreover, we identified the Kla of Scl25a4 and Slc25a5 in the Ca2+ signaling pathway, but the Kla of Vdac1 was eliminated, as confirmed in vivo. Overall, these results provide new insights into lactylation involved in the underlying mechanism of CIRI because this post-translational modification affects the mitochondrial apoptosis pathway and mediates neuronal death. Therefore, this study may enable us to develop new molecules with therapeutic properties, which have both theoretical significance and broad clinical application prospects. A new model of cerebral ischemia-reperfusion injury (CIRI) induced by lactylation through the regulation of key proteins of the Ca2+ signaling pathway.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Traumatismo por Reperfusão , Ratos , Humanos , Animais , Ratos Sprague-Dawley , Lisina/uso terapêutico , Isquemia Encefálica/metabolismo , Traumatismo por Reperfusão/metabolismo
3.
Graefes Arch Clin Exp Ophthalmol ; 260(9): 2829-2836, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35435446

RESUMO

PURPOSE: To compare the predictive refractive error (PRE) of intraocular lens (IOL) power between retinal vascular and vitreomacular interface diseases after phacovitrectomy. METHODS: We retrospectively reviewed patients who underwent phacovitrectomy for various retinal diseases. Patients with retinal vascular diseases and vitreomacular interface diseases were included in group A and group B, respectively. Age- and gender-matched senile cataract patients with phacoemulsification were set as controls. The mean PRE and absolute value of refractive error (ARE) among different groups were compared. The associated risk factors with ARE were also analyzed in the univariate and multivariate analyses. RESULTS: In total, 106 patients (Group A), 108 patients (Group B), and 110 patients as controls were included. The PRE in Group A (- 0.35 ± 0.83D) and Group B (- 0.53 ± 0.74D) were more myopic compared to the control group (- 0.11 ± 0.58D) (p < 0.05). The ARE in Group A (0.70 ± 0.57D) and Group B (0.75 ± 0.51D) were significantly higher compared to the control group (0.47 ± 0.35D) (p < 0.05). There were no significant differences in the PRE and ARE values between the two study groups (p = 0.267 and 0.861, respectively). There were no significant differences of the PRE and ARE in the eyes with silicone oil tamponade (- 0.63 ± 0.75D, 0.81 ± 0.54D) and gas tamponade (- 0.42 ± 0.83D, 0.74 ± 0.56D) (p = 0.693 and 0.988, respectively). In the multivariate model, preoperative LogMAR visual acuity (ß = 0.162, 95%CI = 0.113-0.211, p < 0.001), mean corneal curvature (ß = 0.105, 95% CI = 0.074-0.135, p < 0.001), and age (ß = 0.012, 95% CI = 0.005-0.019, p = 0.001) were all positively correlated with the ARE. CONCLUSIONS: Postoperative myopic shift after phacovitrectomy may be comparable in retinal vascular diseases and vitreomacular interface diseases, no matter the gas or silicone oil tamponade. Older age, steeper corneal curvature, and worse preoperative visual acuity could produce more prediction errors.


Assuntos
Catarata , Lentes Intraoculares , Miopia , Facoemulsificação , Erros de Refração , Doenças Retinianas , Doenças Vasculares , Humanos , Implante de Lente Intraocular , Refração Ocular , Estudos Retrospectivos , Óleos de Silicone , Vitrectomia
4.
Korean J Ophthalmol ; 36(3): 210-217, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35067018

RESUMO

PURPOSE: To assess the feasibility of applying ultra-widefield fundus (UWF) images for macular staphyloma area (MSA) measurement and investigate the associated factors with MSA. METHODS: This is a retrospective study. MSA was measured by UWF imaging. Central foveal thickness, subfoveal choroidal thickness, subfoveal scleral thickness were measured on spectral domain optical coherence tomography. Intraclass correlation coefficients of MSA measurement would be evaluated. Multiple linear regression analysis was used to analyze the associated factors with MSA. RESULTS: In total, 135 eyes of 92 patients were enrolled. The mean age was 64.73 ± 10.84 years. Mean MSA on UWF image was 279.67 ± 71.70 mm2. Intraclass correlation coefficients of MSA measurement was 0.965 (95% confidence interval [CI], 0.946 to 0.977; p < 0.001). In the multiple linear regression analysis, after adjusting for subfoveal choroidal thickness, best-corrected visual acuity, central foveal thickness, and subfoveal scleral thickness, the factors independently related to MSA were axial length (ß = 8.352; 95% CI, 3.306 to 13.398; p = 0.001), sex (ß = -26.673; 95% CI, -51.759 to -1.586; p = 0.037), age (ß = 1.184; 95% CI, 0.020 to 2.348; p = 0.046). CONCLUSIONS: It is feasible to measure MSA on UWF image. Female, longer axial length, and older age may indicate larger MSA.


Assuntos
Miopia Degenerativa , Idoso , Corioide , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Acuidade Visual
5.
Food Chem ; 372: 131258, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34627086

RESUMO

Microwave-mediated immiscible binary solvent extraction (MIBSE) was applied to simultaneously extract oil and epigoitrin from Orychophragmus violaceus seeds. The upper phase of n-hexane was used to obtain oil, and the lower phase of ethanol solution was used to obtain epigoitrin. Factors potentially affecting the yields of oil and epigoitrin were systematically investigated. The optimum conditions were an ethanol volume fraction of 65%, liquid-solid ratio of lower-phase of 20 mL/g, liquid-solid ratio of upper-phase of 12 mL/g, microwave irradiation power of 393 W, and microwave irradiation time of 29 min. The actual yields of oil and epigoitrin were 34.08% ± 1.38% and 11.86 ± 0.47 mg/g, respectively. GC-MS analysis illustrated that the seed oils obtained by MIBSE and Soxhlet extraction exhibited similar fatty acid compositions. The separated epigoitrin was determined by HPLC analyses, which obtained a purity of 91.25% ± 3.83%, follwed by NMR determinations.


Assuntos
Micro-Ondas , Sementes , Óleos , Oxazolidinonas , Óleos de Plantas , Solventes
6.
Biotechnol Biofuels ; 14(1): 21, 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33446264

RESUMO

BACKGROUND: Predatory flagellates and ciliates are two common bio-contaminants which frequently cause biomass losses in Chlorella mass culture. Efficient and targeted ways are required to control these contaminations in Chlorella mass cultivation aiming for biofuel production especially. RESULTS: Five surfactants were tested for its ability to control bio-contaminations in Chlorella culture. All five surfactants were able to eliminate the contaminants at a proper concentration. Particularly the minimal effective concentrations of sodium dodecyl benzene sulfonate (SDBS) to completely eliminate Poterioochromonas sp. and Hemiurosomoida sp. were 8 and 10 mg L-1, respectively, yet the photosynthesis and viability of Chlorella was not significantly affected. These results were further validated in Chlorella mass cultures in 5, 20, and 200 m2 raceway ponds. CONCLUSIONS: A chemical method using 10 mg L-1 SDBS as pesticide to control predatory flagellate or ciliate contamination in Chlorella mass culture was proposed. The method helps for a sustained microalgae biomass production and utilization, especially for biofuel production.

7.
Bioresour Technol ; 317: 124025, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32836037

RESUMO

Large-scale cultivation of Haematococcus pluvialis is frequently contaminated by the destructive fungus Paraphysoderma sedebokerense, which can cause huge losses in astaxanthin production. Here, we propose the use of four commercial surfactants to control P. sedebokerense contamination in H. pluvialis cultures. In laboratory experiments, sodium dodecylbenzene sulfonate, sodium dodecyl sulfate and primary alcohol ethoxylate treatments showed inhibitory effects on fungal contamination. Moreover, sodium dodecylbenzene sulfonate was the most promising because treatment at 7 mg L-1 was effective against fungal infection without negatively affecting the growth or astaxanthin contents of H. pluvialis. This could be ascribed to their different cell coverings and structures. Additionally, applying sodium dodecylbenzene sulfonate to open raceway ponds prevented fungal contamination, and astaxanthin production reached 1.82 g m-2. Therefore, sodium dodecylbenzene sulfonate can be used as an effective and economical control agent for commercial production of astaxanthin fromH. pluvialis.


Assuntos
Clorofíceas , Tensoativos , Fungos , Lagoas
8.
J Healthc Eng ; 2020: 2785464, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32724504

RESUMO

Automatic bone segmentation from a chest radiograph is an important and challenging task in medical image analysis. However, a chest radiograph contains numerous artifacts and tissue shadows, such as trachea, blood vessels, and lung veins, which limit the accuracy of traditional segmentation methods, such as thresholding and contour-related techniques. Deep learning has recently achieved excellent segmentation of some organs, such as the pancreas and the hippocampus. However, the insufficiency of annotated datasets impedes clavicle and rib segmentation from chest X-rays. We have constructed a dataset of chest X-rays with a raw chest radiograph and four annotated images showing the clavicles, anterior ribs, posterior ribs, and all bones (the complete set of ribs and clavicle). On the basis of a sufficient dataset, a multitask dense connection U-Net (MDU-Net) is proposed to address the challenge of bone segmentation from a chest radiograph. We first combine the U-Net multiscale feature fusion method, DenseNet dense connection, and multitasking mechanism to construct the proposed network referred to as MDU-Net. We then present a mask encoding mechanism that can force the network to learn the background features. Transfer learning is ultimately introduced to help the network extract sufficient features. We evaluate the proposed network by fourfold cross validation on 88 chest radiography images. The proposed method achieves the average DSC (Dice similarity coefficient) values of 93.78%, 80.95%, 89.06%, and 88.38% in clavicle segmentation, anterior rib segmentation, posterior rib segmentation, and segmentation of all bones, respectively.


Assuntos
Osso e Ossos/diagnóstico por imagem , Clavícula/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Radiografia Torácica/métodos , Costelas/diagnóstico por imagem , Artefatos , Automação , Bases de Dados Factuais , Aprendizado Profundo , Hipocampo/diagnóstico por imagem , Humanos , Redes Neurais de Computação , Pâncreas/diagnóstico por imagem , Reprodutibilidade dos Testes
9.
Biotechnol Biofuels ; 12: 27, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30805027

RESUMO

BACKGROUND: Microalgae are an important feedstock in industries. Currently, efforts are being made in the non-phototrophic cultivation of microalgae for biomass production. Studies have shown that mixotrophy is a more efficient process for producing algal biomass in comparison to phototrophic and heterotrophic cultures. However, cultivation of microalgae in pilot-scale open ponds in the presence of organic carbon substrates has not yet been developed. The problems are heterotrophic bacterial contamination and inefficient conversion of organic carbon. RESULTS: Laboratory investigation was combined with outdoor cultivation to find a culture condition that favors the growth of alga, but inhibits bacteria. A window period for mixotrophic cultivation of the alga Graesiella sp. WBG-1 was identified. Using this period, a new sequential phototrophic-mixotrophic cultivation (SPMC) method that enhances algal biomass productivity and limits bacteria contamination at the same time was established for microalgae cultivation in open raceway ponds. Graesiella sp. WBG-1 maximally produced 12.5 g biomass and 4.1 g lipids m-2 day-1 in SPMC in a 1000 m2 raceway pond, which was an over 50% increase compared to phototrophic cultivation. The bacterial number in SPMC (2.97 × 105 CFU ml-1) is comparable to that of the phototrophic cultivations. CONCLUSIONS: SPMC is an effective and feasible method to cultivate lipid-rich microalgae in open raceway ponds. Successful scale-up of SPMC in a commercial raceway pond (1000 m2 culture area) was demonstrated for the first time. This method is attractive for global producers of not only lipid-rich microalgae biomass, but also astaxanthin and ß-carotene.

10.
Sci Rep ; 7(1): 14221, 2017 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-29079857

RESUMO

ABSRACT: Due to the thinness and small scale of cirrus clouds, its lateral boundary may be missed by conventional passive remote-sensing techniques and climate models. Here, using satellite observations in June-August from 2006 to 2011, a global dataset for the cirrus cloud lateral boundary (CCLB) was established. The results indicate that the optical properties, such as the lidar backscatter, the depolarization ratio and the optical depth, sharply decrease from cloudy regions to clear-sky regions. There are significant regional differences in optical properties and height and thickness of the CCLB. Based on a quantitative estimation, the strongest longwave warming effects (>0.3 W m-2) are found near the Equator and over tropical continents. The global average longwave warming effect of the CCLB is at least 0.07 W m-2, which is much larger than some of the radiative forcings considered in the Intergovernmental Panel on Climate Change (IPCC) reports. Specifically, the CCLB in traditional "clear-sky" region may be totally missed by current models and IPCC reports, which contributes 28.25% (~0.02 W m-2) of the whole CCLB radiative effect, twice greater than contrail effect. It is recommended that the CCLB effect should be taken account in future climate models and the next IPCC reports.

11.
Sensors (Basel) ; 17(6)2017 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-28587124

RESUMO

In this study, a non-contact laser ultrasonic propagation imaging technique was applied to detect the damage of plate-like structures. Lamb waves were generated by an Nd:YAG pulse laser system, while a galvanometer-based laser scanner was used to scan the preliminarily designated area. The signals of the structural responses were measured using a piezoelectric sensor attached on the front or back side of the plates. The obtained responses were analyzed by calculating the root mean square (RMS) values to achieve the visualization of structural defects such as crack, corrosion, and so on. If the propagating waves encounter the damage, the waves are scattered at the damage and the energy of the scattered waves can be expressed by the RMS values. In this study, notch and corrosion were artificially formed on aluminum plates and were considered as structural defects. The notches were created with different depths and angles on the aluminum plates, and the corrosion damage was formed with different depths and areas. To visualize the damage more clearly, edge detection methodologies were applied to the RMS images and the feasibility of the methods was investigated. The results showed that most of the edge detection methods were good at detecting the shape and/or the size of the damage while they had poor performance of detecting the depth of the damage.

12.
Sensors (Basel) ; 16(12)2016 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-27999252

RESUMO

This paper proposes a non-contact nondestructive evaluation (NDE) technique that uses laser-induced ultrasonic waves to visualize corrosion damage in aluminum alloy plate structures. The non-contact, pulsed-laser ultrasonic measurement system generates ultrasonic waves using a galvanometer-based Q-switched Nd:YAG laser and measures the ultrasonic waves using a piezoelectric (PZT) sensor. During scanning, a wavefield can be acquired by changing the excitation location of the laser point and measuring waves using the PZT sensor. The corrosion damage can be detected in the wavefield snapshots using the scattering characteristics of the waves that encounter corrosion. The structural damage is visualized by calculating the logarithmic values of the root mean square (RMS), with a weighting parameter to compensate for the attenuation caused by geometrical spreading and dispersion of the waves. An intact specimen is used to conduct a comparison with corrosion at different depths and sizes in other specimens. Both sides of the plate are scanned with the same scanning area to observe the effect of the location where corrosion has formed. The results show that the damage can be successfully visualized for almost all cases using the RMS-based functions, whether it formed on the front or back side. Also, the system is confirmed to have distinguished corroded areas at different depths.

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