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1.
Sci Total Environ ; 945: 174119, 2024 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-38906304

RÉSUMÉ

With the death and decomposition of widely distributed photosynthetic organisms, free natural pigments are often detected in surface water, sediment and soil. Whether free pigments can act as photosensitizers to drive biophotoelectrochemical metabolism in nonphotosynthetic microorganisms has not been reported. In this work, we provide direct evidence for the photoelectrophic relationship between extracellular chlorophyll a (Chl a) and nonphotosynthetic microorganisms. The results show that 10 µg of Chl a can produce significant photoelectrons (∼0.34 A/cm2) upon irradiation to drive nitrate reduction in Shewanella oneidensis. Chl a undergoes structural changes during the photoelectric process, thus the ability of Chl a to generate a photocurrent decreases gradually with increasing illumination time. These changes are greater in the presence of microorganisms than in the absence of microorganisms. Photoelectron transport from Chl a to S. oneidensis occurs through a direct pathway involving the cytochromes MtrA, MtrB, MtrC and CymA but not through an indirect pathway involving riboflavin. These findings reveal a novel photoelectrotrophic linkage between natural photosynthetic pigments and nonphototrophic microorganisms, which has important implications for the biogeochemical cycle of nitrogen in various natural environments where Chl a is distributed.


Sujet(s)
Chlorophylle A , Nitrates , Shewanella , Nitrates/métabolisme , Shewanella/métabolisme , Chlorophylle A/métabolisme , Photosynthèse , Oxydoréduction , Photosensibilisants , Chlorophylle/métabolisme
2.
J Magn Reson Imaging ; 2023 Oct 27.
Article de Anglais | MEDLINE | ID: mdl-37888871

RÉSUMÉ

BACKGROUND: The metastatic vascular patterns of hepatocellular carcinoma (HCC) are mainly microvascular invasion (MVI) and vessels encapsulating tumor clusters (VETC). However, most existing VETC-related radiological studies still focus on the prediction of VETC status. PURPOSE: This study aimed to build and compare VETC-MVI related models (clinical, radiomics, and deep learning) associated with recurrence-free survival of HCC patients. STUDY TYPE: Retrospective. POPULATION: 398 HCC patients (349 male, 49 female; median age 51.7 years, and age range: 22-80 years) who underwent resection from five hospitals in China. The patients were randomly divided into training cohort (n = 358) and test cohort (n = 40). FIELD STRENGTH/SEQUENCE: 3-T, pre-contrast T1-weighted imaging spoiled gradient recalled echo (T1WI SPGR), T2-weighted imaging fast spin echo (T2WI FSE), and contrast enhanced arterial phase (AP), delay phase (DP). ASSESSMENT: Two radiologists performed the segmentation of HCC on T1WI, T2WI, AP, and DP images, from which radiomic features were extracted. The RFS related clinical characteristics (VETC, MVI, Barcelona stage, tumor maximum diameter, and alpha fetoprotein) and radiomic features were used to build the clinical model, clinical-radiomic (CR) nomogram, deep learning model. The follow-up process was done 1 month after resection, and every 3 months subsequently. The RFS was defined as the date of resection to the date of recurrence confirmed by radiology or the last follow-up. Patients were followed up until December 31, 2022. STATISTICAL TESTS: Univariate COX regression, least absolute shrinkage and selection operator (LASSO), Kaplan-Meier curves, log-rank test, C-index, and area under the curve (AUC). P < 0.05 was considered statistically significant. RESULTS: The C-index of deep learning model achieved 0.830 in test cohort compared with CR nomogram (0.731), radiomic signature (0.707), and clinical model (0.702). The average RFS of the overall patients was 26.77 months (range 1-80 months). DATA CONCLUSION: MR deep learning model based on VETC and MVI provides a potential tool for survival assessment. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.

3.
Curr Med Imaging ; 19(8): 955-961, 2023.
Article de Anglais | MEDLINE | ID: mdl-35959622

RÉSUMÉ

BACKGROUND: Talaromyces marneffei (T. marneffei) is a heat-dimorphic fungus that commonly causes fatal opportunistic infections in immunocompromised patients, such as those with human immunodeficiency virus (HIV) infection. CASE PRESENTATION: In this case report we describe a case of intracranial infection of T. marneffei in a 42-year-old AIDS patient. Contrast enhanced MRI showed the left occipital lobe mass with ring enhancement, MRS showed elevated AAs and Lip waves in the mass. Surgical resection of the occipital lobe confirmed the lesion to be T. marneffei infection and possibly with tuberculosis after a pathological examination. Patients with intracranial ring enhancing space-occupying lesions on MRI should be considered for intracranial T. marneffei infection. Intracranial T. marneffei infection is relatively rarely reported and recently studied. CONCLUSION: The MRI, in this case, suggests that ring enhancement mass and elevated AAs and Lip waves are helpful in the diagnosis of T. marneffei infection.


Sujet(s)
Syndrome d'immunodéficience acquise , Infections à VIH , Mycoses , Talaromyces , Humains , Adulte , Syndrome d'immunodéficience acquise/complications , Mycoses/complications , Mycoses/imagerie diagnostique , Infections à VIH/complications , Infections à VIH/microbiologie
4.
ACS Polym Au ; 2(5): 299-312, 2022 Oct 12.
Article de Anglais | MEDLINE | ID: mdl-36267546

RÉSUMÉ

The small specific entropy of mixing of high molecular weight polymers implies that most blends of dissimilar polymers are immiscible with poor physical properties. Historically, a wide range of compatibilization strategies have been pursued, including the addition of copolymers or emulsifiers or installing complementary reactive groups that can promote the in situ formation of block or graft copolymers during blending operations. Typically, such reactive blending exploits reversible or irreversible covalent or hydrogen bonds to produce the desired copolymer, but there are other options. Here, we argue that ionic bonds and electrostatic correlations represent an underutilized tool for polymer compatibilization and in tailoring materials for applications ranging from sustainable polymer alloys to organic electronics and solid polymer electrolytes. The theoretical basis for ionic compatibilization is surveyed and placed in the context of existing experimental literature and emerging classes of functional polymer materials. We conclude with a perspective on how electrostatic interactions might be exploited in plastic waste upcycling.

5.
Acta Radiol ; 63(8): 1005-1013, 2022 Aug.
Article de Anglais | MEDLINE | ID: mdl-34233501

RÉSUMÉ

BACKGROUND: The relevance of Epstein-Barr virus (EBV) in gastric carcinoma has been represented by the existence of EBV-encoded small RNA (EBER) in the tumor cells and has prognostic significance in gastric cancer, while gastric adenocarcinoma represents the most frequently occurring gastric malignancy. PURPOSE: To observe the capacity of radiomic features extracted from contrast-enhanced computed tomography (CE-CT) images to differentiate EBER-positive gastric adenocarcinoma from EBER-negative ones. MATERIAL AND METHODS: A total of 54 patients with gastric adenocarcinoma (EBER-positive: 27, EBER-negative: 27) were retrospectively examined. Radiomic imaging features were extracted from all regions of interest (ROI) delineated by two experienced radiologists on late arterial phase CT images. We distinguished related radiomic features through the two-tailed t test and applied them to construct a decision tree model to evaluate whether EBER in situ hybridization positive had appeared. RESULTS: Nine radiomics features were significantly related to EBER in situ hybridization status (P < 0.05), four of which were used to build the decision tree through backward elimination: Correlation_ AllDirection_offset7, Correlation_ angle135_offset7, RunLengthNonuniformity_ AllDirection_offset1_SD, and HighGreyLevelRunEmphasis_ AllDiretion_offset1_SD. The decision tree model consisted of seven decision nodes and six terminal nodes, three of which demonstrated positive EBER in situ hybridization. The specificity, sensitivity, and accuracy of the model were 84%, 80%, and 81.7%, respectively. The area under the curve of the decision tree model was 0.87. CONCLUSION: Radiomics based on CE-CT could be applied to predict EBER in situ hybridization status preoperatively in patients with gastric adenocarcinoma.


Sujet(s)
Adénocarcinome , Infections à virus Epstein-Barr , Tumeurs de l'estomac , Adénocarcinome/imagerie diagnostique , Infections à virus Epstein-Barr/complications , Infections à virus Epstein-Barr/imagerie diagnostique , Herpèsvirus humain de type 4/génétique , Humains , Études rétrospectives , Tumeurs de l'estomac/imagerie diagnostique , Tumeurs de l'estomac/anatomopathologie , Tomographie , Tomodensitométrie
6.
ACS Macro Lett ; 10(1): 104-109, 2021 Jan 19.
Article de Anglais | MEDLINE | ID: mdl-35548991

RÉSUMÉ

Polymer electrolytes with high Li+-ion conductivity provide a route toward improved safety and performance of Li+-ion batteries. However, most polymer electrolytes suffer from low ionic conduction and an even lower Li+-ion contribution to the conductivity (the transport number, t+), with the anion typically transporting over 80% of the charge. Here, we show that subtle and potentially undetected associations within a polymer electrolyte can entrain both the anion and the cation. When removed, the conductivity performance of the electrolyte can be improved by almost 2 orders of magnitude. Importantly, while some of this improvement can be attributed to a decreased glass transition temperature, Tg, the removal of the amide functional group reduces interactions between the polymer and the Li+ cations, doubling the Li+ t+ to 0.43, as measured using pulsed-field-gradient NMR. This work highlights the importance of strategic synthetic design and emphasizes the dual role of Tg and ion binding for the development of polymer electrolytes with increased total ionic conductivity and the Li+ ion contribution to it.

7.
Chinese Journal of School Health ; (12): 675-678, 2021.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-877125

RÉSUMÉ

Objective@#To understand the status of family sex education and associated factors among preschoolers in Wuhu, providing scientific basis for child family sex education.@*Methods@#From July to August 2020, random cluster sampling was used to select 481 children from 5 kindergartens in Wuhu. A questionnaire survey among parents of these preschoolers regarding family sex education status and its influencing factors.@*Results@#A total of 285(59.25%) parents reported family sex education for children, and 196(40.75%) did not practice family sex education for their children. Multivariate Logistic regression analysis showed parental awareness of sex education content(OR=3.06, 95%CI=1.95-4.78), parental anxiety for child sexual assault (OR=1.82, 95%CI=1.11-2.99) were associated with higher rate of family sex education.@*Conclusion@#Family sex education among preschoolers in Wuhu should be further promoted. Sex education training towards parents might help improve children s family sex education.

8.
ACS Nano ; 14(10): 13754-13764, 2020 Oct 27.
Article de Anglais | MEDLINE | ID: mdl-32866375

RÉSUMÉ

Salt-doped A/B/AB ternary polymer blends, wherein an AB copolymer acts as a surfactant to stabilize otherwise incompatible A and B homopolymers, display a wide range of nanostructured morphologies with significant tunability. Among these structures, a bicontinuous microemulsion (BµE) has been a notable target. Here, we report the surprising appearance of a robust C15 Laves phase, at compositions near where the BµE has recently been reported, in lithium bis(trifluoromethane) sulfonimide (LiTFSI)-doped low-molar-mass poly(ethylene oxide) (PEO)/polystyrene (PS)/symmetric PS-b-PEO block copolymer blends. The materials were analyzed by a combination of small-angle X-ray scattering (SAXS), 1H NMR spectroscopy, and impedance spectroscopy. The C15 phase emerges at a high total homopolymer volume fraction ϕH = 0.8 with a salt composition r = 0.06 (Li+/[EO]) and persists as a coexisting phase across a large area of the isothermal phase diagram with high PS homopolymer compositions. Notably, the structure exhibits a huge unit cell size, a = 121 nm, with an unusually high micelle core volume fraction (fcore = 0.41) and an unusually low fraction of amphiphile (20%). This unit cell dimension is at least 50% larger than any previously reported C15 phase in soft matter, despite the low molar masses used, unlocking the possibility of copolymer-based photonic crystals without compromising processability. The nanostructured phase evolution from lamellar to hexagonal to C15 along the EO60 isopleth (ϕPEO,homo-LiTFSI/ϕH = 0.6) is rationalized as a consequence of asymmetry in the homopolymer solubility limit for each block, which leads to exclusion of PS homopolymer from the PS-b-PEO brush prior to exclusion of the PEO homopolymer, driving increased interfacial curvature and favoring the emergence of the C15 Laves phase.

9.
Transl Oncol ; 12(5): 749-756, 2019 May.
Article de Anglais | MEDLINE | ID: mdl-30878893

RÉSUMÉ

Since accurate grading of gliomas has important clinical value, the aim of this study is to evaluate the diagnostic efficacy of perfusion values derived from arterial spin labeling (ASL) to grade gliomas. In addition, the correlation between perfusion and isocitrate dehydrogenase 1 (IDH1) genotypes and chromosome arms 1p and 19q (1p/19q) status of gliomas was assessed. A total of 52 cases of supratentorial gliomas in adults who received ASL imaging were enrolled in this retrospective study. The cerebral blood flow (CBF) images derived from ASL and anatomical maps were normalized to the Montreal Neurological Institute coordinate system and matched. The mean CBF (meanCBF), the maximum CBF (maxCBF), and their relative values (rmeanCBF and rmaxCBF, respectively) were assessed in each case. The tumor grades, IDH1 genotypes, and 1p/19q status were diagnosed according to the 2016 WHO criteria. Receiver operating characteristic curves were performed to assess the efficacy of perfusion parameters for grading. Qualitatively, all gliomas were divided into high- and low-perfusion groups. The crosstabs chi-square test of independence was performed to calculate contingency coefficient (C) and Cramer V coefficient to assess the correlation between perfusion and IDH1 genotypes and 1p/19q status of gliomas. The rmaxCBF showed the best diagnostic efficacy; meanwhile, rmeanCBF had the best specificity for grade discrimination. In astrocytoma, there was a mild correlation between IDH1 genotypes and tumor perfusion with the Cramer's V coefficient of 0.378. There was no significant association between 1p/19q codeletion and perfusion in grade II and III gliomas.

10.
Anal Chim Acta ; 898: 101-8, 2015 Oct 22.
Article de Anglais | MEDLINE | ID: mdl-26526915

RÉSUMÉ

Optical sensors for environmental humidity have been constructed from poly (N-isopropylacrylamide)-co-acrylic acid (pNIPAm-co-AAc) microgels. The devices were constructed by first depositing a monolithic layer of pNIPAm-co-AAc microgels on a Au-coated glass substrate followed by the addition of another Au layer on top. The resultant assembly showed visual color, and exhibited multipeak reflectance spectra. We found that the thickness of the device's microgel layer depended on environmental humidity, which corresponded to a change in the device's optical properties. Specifically, at low humidity the microgel layer was collapsed, while it absorbed water from the atmosphere (and swelled) as the humidity increased. Additionally, we investigated how the deposition of the hygroscopic polymer poly (diallyldimethylammonium chloride) (pDADMAC) onto the microgel layer (prior to final Au layer deposition) influenced the devices humidity response. We found that the devices were more sensitive to humidity as the number of pDADMAC layers in the device increased. Finally, we evaluated the device performance at various temperatures, and found that the sensitivity was enhanced at low temperature, although the response was more linear at elevated temperature.

11.
Chemistry ; 20(18): 5317-26, 2014 Apr 25.
Article de Anglais | MEDLINE | ID: mdl-24665038

RÉSUMÉ

Two aggregation-induced emission active luminogens (TPE-pTPA and TPE-mTPA) were successfully synthesized. For comparison, another six similar compounds were prepared. Because of the introduced hole-dominated triphenylamine (TPA), fluorene groups with high luminous efficiency, and unconjugated linkages, the π conjugation length of the obtained luminogens is effectively restricted to ensure their blue emission. The undoped organic light-emitting diodes based on TPE-pTPA and TPE-mTPA exhibited blue or deep-blue emissions, low turn-on voltages (3 V), and high electroluminescence efficiencies with Lmax, ηC,max, and ηP,max values of up to 26,697 cd m(-2), 3.37 cd A(-1), and 2.40 Lm W(-1).

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