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1.
J Am Chem Soc ; 146(32): 22661-22674, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39099104

RESUMEN

Synthesizing anisotropic polymeric nanoparticles (NPs) with well-defined shapes, dimensions, and molecular orientations is a very challenging task. Herein, we report the synthesis of surprisingly highly uniform shape-anisotropic polymer NPs with uniaxial internal molecular orientation. Keys to our method are synchronized polymerization and self-assembly (SPSA), which can even be realized by regular dispersion polymerization. This is demonstrated using a monomer containing a rigid 4-nitroazobenzene (NAB) side group. The short nucleation period, the completion of microphase separation before molecular motion is frozen, and sufficient low particle/solvent interfacial tension are shown to be the origins of the highly uniform dimensions, single liquid crystal domains, and well-defined anisotropic shape of particles. The liquid crystallization ability of the polymers, control of molecular weight distribution, and the polymerization kinetics are identified as three key factors controlling the NP formation. The uniformity of these NPs facilitates their SA formation into colloidal crystals. The particles exhibit optically anisotropic properties depending on orientations and, in particular, show intriguing photoswitchable LC-glass (order-disorder) transition, which can be used for the detection of ultraviolet (UV) light and allows the fabrication of photoreversible colloidal films.

2.
J Am Chem Soc ; 145(3): 1548-1556, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36637214

RESUMEN

Poly(ethylene oxide) has been widely investigated as a potential separator for solid-state lithium metal batteries. However, its applications were significantly restricted by low ionic conductivity and a narrow electrochemical stability window (<4.0 V vs Li/Li+) at room temperature. Herein, a novel molecular self-assembled ether-based polyrotaxane electrolyte was designed using different functional units and prepared by threading cyclic 18-crown ether-6 (18C6) to linear poly(ethylene glycol) (PEG) via intermolecular hydrogen bond and terminating with hexamethylene diisocyanate trimer (HDIt), which was strongly confirmed by local structure-sensitive solid/liquid-state nuclear magnetic resonance (NMR) techniques. The designed electrolyte has shown an obviously increased room-temperature ionic conductivity of 3.48 × 10-4 S cm-1 compared to 1.12 × 10-5 S cm-1 without assembling polyrotaxane functional units, contributing to the enhanced cycling stability of batteries with both LiFePO4 and LiNi0.8Co0.15Al0.05O2 cathode materials. This advanced molecular self-assembled strategy provides a new paradigm in designing solid polymer electrolytes with demanded performance for lithium metal batteries.

3.
Toxicol Appl Pharmacol ; 463: 116412, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36764612

RESUMEN

Doxorubicin (DOX), which is widely used for the treatment of cancer, induces cardiomyopathy associated with NADPH oxidase-derived reactive oxygen species. GSK2795039 is a novel small molecular NADPH oxidase 2 (Nox2) inhibitor. In this study, we investigated whether GSK2795039 prevents receptor-interacting protein kinase 1 (RIP1)-RIP3-mixed lineage kinase domain-like protein (MLKL)-mediated cardiomyocyte necroptosis in DOX-induced heart failure through NADPH oxidase inhibition. Eight-week old mice were randomly divided into 4 groups: control, GSK2795039, DOX and DOX plus GSK2795039. H9C2 cardiomyocytes were treated with DOX and GSK2795039. In DOX-treated mice, the survival rate was reduced, left ventricular (LV) end-systolic dimension was increased and LV fractional shortening was decreased, and these alterations were attenuated by the GSK2795039 treatment. GSK2795039 inhibited not only myocardial NADPH oxidase subunit gp91phox (Nox2) protein, but also p22phox, p47phox and p67phox proteins and prevented oxidative stress 8-hydroxy-2'-deoxyguanosine levels in DOX-treated mice. RIP3 protein and phosphorylated RIP1 (p-RIP1), p-RIP3 and p-MLKL proteins, reflective of their respective kinase activities, markers of necroptosis, were markedly increased in DOX-treated mice, and the increases were prevented by GSK2795039. GSK2795039 prevented the increases in serum lactate dehydrogenase and myocardial fibrosis in DOX-treated mice. Similarly, in DOX-treated cardiomyocytes, GSK2795039 improved cell viability, attenuated apoptosis and necrosis and prevented the increases in p-RIP1, p-RIP3 and p-MLKL expression. In conclusion, GSK2795039 prevents RIP1-RIP3-MLKL-mediated cardiomyocyte necroptosis through inhibition of NADPH oxidase-derived oxidative stress, leading to the improvement of myocardial remodeling and function in DOX-induced heart failure. These findings suggest that GSK2795039 may have implications for the treatment of DOX-induced cardiomyopathy.


Asunto(s)
Insuficiencia Cardíaca , Miocitos Cardíacos , Ratones , Animales , Miocitos Cardíacos/metabolismo , Necroptosis , Necrosis/metabolismo , Apoptosis/fisiología , Estrés Oxidativo , Doxorrubicina/metabolismo , NADPH Oxidasas/metabolismo , Proteínas Quinasas/metabolismo
4.
Lupus ; 32(6): 746-755, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37051771

RESUMEN

BACKGROUND: Systemic lupus erythematosus (SLE) is a typical chronic immune disorder with clinical heterogeneity. The systemic abnormal immune response not only challenges the diagnosis and treatment of the disease itself but also the secondary antiphospholipid syndrome (APS), characterized by recurrent arterial or venous thrombosis, recurrent spontaneous abortion, or stillbirth. Clinical interest has primarily focused on primary APS's pathological and clinical features. However, differences in clinical features and laboratory indicators between SLE with or without APS are still lacking, especially differences between circulating lymphocytes, which are critical in the pathogenesis of SLE and its complications. METHODS: In this retrospective study, we collected and analyzed clinical characteristics, general laboratory indicators, immunological indicators, and circulating lymphocyte subsets of SLE with or without APS. RESULTS: Systemic lupus erythematosus with APS (SLE-APS) had elevated SLEDAI scores, hospitalization costs and time, and frequencies of central nervous system symptoms and spontaneous abortion compared with those without APS. SLE-APS had higher positive anti-Cardiolipin antibodies, anti-ß2 Glycoprotein 1 antibodies, and perinuclear antineutrophil cytoplasmic antibody (pANCA) than none-APS patients. Compared with healthy controls (HCs), the circulating lymphocyte subsets were altered to some extent in all patients, especially in patients with SLE-APS. Reduced Tregs and positive pANCA were independent risk factors for SLE secondary APS. CONCLUSION: The present study revealed a robust association between APS secondary to SLE and reduced Tregs and positive pANCA, which provides essential information regarding the diagnosis and therapeutic possibilities of APS secondary to SLE.


Asunto(s)
Aborto Habitual , Síndrome Antifosfolípido , Lupus Eritematoso Sistémico , Femenino , Embarazo , Humanos , Síndrome Antifosfolípido/diagnóstico , Lupus Eritematoso Sistémico/complicaciones , Estudios Retrospectivos , Anticuerpos Anticardiolipina , Aborto Habitual/etiología
5.
Soft Matter ; 19(37): 7161-7171, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37702037

RESUMEN

Short ring polymers are expected to behave nearly Rouse-like due to the little effect of topological constraints of non-knot and non-concatenation. However, this notion is questioned because of several simulation and experiment findings in recent times, which requires a further more quantitative study. Therefore, we perform a deep investigation of statics and dynamics of flexible short ring polymers (N < 2Ne) in melts via molecular dynamics simulations by further taking linear analogues as well as all-crossing ring and linear polymers with switched off topological constraints for comparisons and demonstrate the noticeable deviations from the Rouse model in terms of local and global scales. Although the overall size is compact, the subchains are swollen, which is traced back to the deeper "segmental correlation hole" effect. The same scaling relationship of the non-Gaussian deviation of the static structure factor holds, but the deviation magnitude of rings is larger than that of linear analogues. By checking the non-Gaussian parameter and autocorrelation function of center-of-mass velocity, the physical origin of anomalous sub-diffusions of short rings is identified as unscreened viscoelastic hydrodynamic interactions and not correlation hole effects, like linear analogues.

6.
J Appl Microbiol ; 134(2)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36724271

RESUMEN

AIMS: Human skin is the first barrier against pathogens and environmental hazards and the highest contact frequency occurs with the hands. Environmental and personal metabolic factors may affect skin microbes. This study was conducted to clarify the diversity in the skin microbial community that was mainly due to individual skin metabolites rather than lifestyle and environmental factors. METHODS AND RESULTS: Skin microbiota samples were collected from 11 volunteers who met similar lifestyle inclusion criteria. The V3-V4 region of the 16S rRNA gene was amplified. After library construction and sequencing, we compared the composition and diversity of the hand skin microbiota in different sexes and BMI groups with bioinformation analysis. The whole sequence data were annotated as 42 phyla, 538 families, and 1215 genera. Four dominant phyla accounted for 97% of the total including Actinobacteriota (50.18%), Firmicutes (23.85%), Proteobacteria (21.64%) and Bacteroidota (2.05%). The genera that were detected in all subjects with high relative abundance were Cutibacterium, Staphylococcus, Corynebacterium, Streptococcus, Lawsonella, Enhydrobacter, Escherichia-Shigella, Asaia and Micrococcus. CONCLUSIONS: The diversity and richness of the microbiota of male hand skin in our study was higher than that of females. Interestingly, Cutibacterium, Staphylococcus, and Corynebacterium might serve as important skin microbiota to distinguish sexes.


Asunto(s)
Microbiota , Femenino , Humanos , Masculino , ARN Ribosómico 16S/genética , Microbiota/genética , Bacterias/genética , Bacteroidetes/genética , Estilo de Vida
7.
Clin Lab ; 69(9)2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37702688

RESUMEN

BACKGROUND: The goal of the study is to improve the understanding of complex karyotype acute basophilic leukemia with reactive mast cell hyperplasia. METHODS: A case of clinical and laboratory characteristics of complex karyotype acute basophilic leukemia with reactive mast cell hyperplasia and review of related literature of patient with acute basophilic leukemia were retrospectively analyzed. RESULTS: Laboratory tests: alanine aminotransferase 225 U/L, aspartate aminotransferase 129 U/L, total protein 3.0 g/L, albumin 25.0 g/L, globulin 17.8 g/L, total bilirubin 183.9 µmol/L, indirect bilirubin 65.6 µmol/L, D-dimer 13.02 mg/L, prothrombin time 19.30 S, white blood cell 37.30 x 109/L, red blood cells 2.06 x 1012/L, hemoglobin 71 g/L, platelets 13 x 109/L, and basophilic granulocyte cells 5.01 x 109/L. Bone marrow smear: a large number of abnormal primitive cells were scattered and distributed. The characteristics of these cells were as follows: the cell body size was different, most of them were round or quasi-round, the cytoplasm volume was medium, and the cytoplasm was stained gray blue. The cytoplasmic processes were visible, and basophilic particles were visible in part of the cytoplasm and/or on the nucleus. The nuclei were mostly round or almost round, with distortion and folding. The chromatin was detailed, the nucleoli varied in number, and some nucleoli were deeply stained. The cells showed double and multiple nuclei, scattered and occasionally small clumps. Bone marrow biopsy: acute myeloid leukemia, not excluding basophilic leukemia. Bone marrow molecular biology: All 29 myeloid leukemia genes, including RARA and BCR-ABL fusion genes, were negative. Flow cytometry results showed abnormal cell population which accounted for 21.98% of nuclear cells. The phenotypes are CD33++, CD38+, CD13+, CD123+, CD7+, CD36+, CD203c+, CD81+, part of CD34+, part of HLA-DR+, CD4 weak+, weak CD117+, the TDT-, cCD3-, cCD79a-, MPO-, CD11c-, CD25-, CD2-. In addition, mast cells accounted for 1.15% of nuclear cells, expressing CD203c, but not CD25 and CD2. Karyotype analysis results were 46, XY, -7, psudic (9; 19) (p24; p13.3), add (15) (p12), add (21) (q22), +r, +1 - 2 mar [cp20]. CONCLUSIONS: Acute basophilic leukemia (ABL) is a rare malignant hematologic tumor. Bone marrow smears, biopsies, flow cytometry, and cytogenetic tests play an important role in the diagnosis and differentiation of complex karyotype acute basophilic leukemia with reactive mast cell hyperplasia.


Asunto(s)
Leucemia Basofílica Aguda , Humanos , Mastocitos , Hiperplasia , Estudios Retrospectivos , Cariotipo
8.
Ren Fail ; 45(2): 2253922, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37724562

RESUMEN

Serum anti-phospholipase A2 receptor (anti-PLA2R) antibody is used for the noninvasive diagnosis of idiopathic membranous nephropathy (IMN). However, the cutoff value of anti-PLA2R antibodies in IMN patients is debatable. This study aimed to investigate the cutoff value of anti-PLA2R antibodies for diagnosing IMN and the correlation of anti-PLA2R antibodies with clinical parameters and prognosis. A total of 252 IMN patients and 521 non-IMN patients with both renal biopsy and serum anti-PLA2R antibody data from April 2017 to November 2019 were enrolled. Anti-PLA2R antibody was detected by an enzyme-linked immunosorbent assay. The anti-PLA2R antibody titer was higher in the IMN group than in the non-IMN group (153.1 ± 22.4 vs. 2.0 ± 0.2 RU/mL, p < 0.001). The optimal anti-PLA2R antibody cutoff value for diagnosing IMN was 2.5 RU/mL, with a sensitivity, specificity, and Youden index of 85.7%, 88.3%, and 0.740, respectively. There was a significant positive correlation between anti-PLA2R antibody and 24-h urinary protein levels (r = 0.341, p < 0.001), and a significant negative correlation between anti-PLA2R antibody and serum albumin levels (r=-0.274, p < 0.001) in patients with IMN. The remission rates positively correlated with the immunosuppressive usage rates and increased from the low- to the high-titer subgroup. Multivariable Cox regression analysis showed that immunosuppressive therapy (adjusted HR = 4.656; 95% confidence interval [CI], 1.461-14.839; p = 0.009) was associated with a higher remission rate in patients with IMN. The optimal Anti-PLA2R antibody cutoff value for diagnosing IMN was 2.5 RU/mL, which was much lower than that indicated by the manufacturer. If IMN is actively treated, patients can have much better prognoses.Trial registration: retrospectively registered.


Asunto(s)
Glomerulonefritis Membranosa , Humanos , Estudios Retrospectivos , Glomerulonefritis Membranosa/diagnóstico , Glomerulonefritis Membranosa/tratamiento farmacológico , Pronóstico , China , Ensayo de Inmunoadsorción Enzimática
9.
BMC Nurs ; 22(1): 179, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37221496

RESUMEN

BACKGROUND: Advanced Practice Nursing (APN) have been highly valued and an integral part of the health care system. Development and establishment of new APN roles is a complex process that has resulted from a wide variety of reasons, key component is a lack of a competency map delineation and role evaluation. Currently, however, competence framework has not been compared at an international level. In mainland China, APN have been introduced in some organizations but their competency domains have not yet been clearly defined, this study aimed to identify the core competencies for advanced practice nursing. METHODS: This study was performed in two phases: first, in-depth and semi-structured individual interviews with 46 participants from key stakeholders were carried out followed by a qualitative content analysis, then an item pool of core competencies was constructed by extracting data from the first phase and the results from previous studies, scales and documents; second, a Delphi technique was conducted with the participation of 28 experts from 7 areas of China to form the final core competency framework for advanced practice nursing. RESULTS: Through the qualitative phase, the core competency framework with six domains and 70 items emerged and then entered into the Delphi phase. Twenty-eight of 30 experts finished 2 rounds of Delphi approaches. The final core competencies for advanced practice nursing consisted of six domains with 61 items, including direct clinical nursing practice, research and evidence-based nursing practice, professional development, organization and management, mentoring and consultation, and ethical/legal practice. CONCLUSION: This core competency framework consisted of six domains with 61 items can be used in competency-based education to cultivate advanced practice nurses as well as competency level assessment.

10.
Soft Matter ; 18(11): 2176-2192, 2022 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35212698

RESUMEN

Nanocomposite tectons (NCTs) are nanocomposite building blocks consisting of nanoparticle cores functionalized with a polymer brush, where each polymer chain terminates in a supramolecular recognition group capable of driving particle assembly. Like other ligand-driven nanoparticle assembly schemes (for example those using DNA-hybridization or solvent evaporation), NCTs are able to make colloidal crystal structures with precise particle organization in three dimensions. However, despite the similarity of NCT assembly to other methods of engineering ordered particle arrays, the crystallographic symmetries of assembled NCTs are significantly different. In this study, we provide a detailed characterization of the dynamics of hybridizations through universal (independent of microscopic details) parameters. We perform rigorous free energy calculations and identify the persistence length of the ligand as the critical parameter accounting for the differences in the phase diagrams of NCTs and other assembly methods driven by hydrogen bond hybridizations. We also report new experiments to provide direct verification for the predictions. We conclude by discussing the role of non-equilibrium effects and illustrating how NCTs provide a unification of the two most successful strategies for nanoparticle assembly: solvent evaporation and DNA programmable assembly.


Asunto(s)
Nanocompuestos , Nanopartículas , Cristalografía , ADN/química , Hibridación de Ácido Nucleico
11.
BMC Microbiol ; 21(1): 13, 2021 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-33407122

RESUMEN

BACKGROUND: The aim was to determine the potential association of the gut microbiota composition, especially the abundance of Actinobacteria, as well as the differentiation of functional and resistance genes with age (young adults vs elderly subjects) in China. RESULTS: The patterns of relative abundance of all bacteria isolated from fecal samples differed between young adults and elderly subjects, but the alpha diversity (Chao1 P = 0.370, Shannon P = 0.560 and Simpson P = 0.270) and beta diversity (ANOSIM R = 0.031, P = 0.226) were not significantly different. There were 3 Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathways (carbon metabolism, inositol phosphate metabolism, and sesquiterpenoid and triterpenoid biosynthesis) and 7 antibiotic resistant genes (ARGs) (macrolide lincosamide-streptogramin B (MLSB), tetracycline, aminoglycoside, sulfonamide, fosmidomycin, lincomycin, and vancomycin) that showed significant differences between the 2 groups (all P < 0.05). The abundance of Actinomycetes was enriched (about 2.4-fold) in young adults. Bifidobacteria dominated in both young adults and elderly subjects, with overall higher abundances in young adults (P > 0.05). Only the Bifidobacterium_dentium species showed significant differences between the 2 groups (P = 0.013), with a higher abundance in elderly subjects but absent in young adults. CONCLUSIONS: The present study revealed that there were 3 KEGG metabolic pathways and 7 ARGs as well as enhanced Bifidobacterium_dentium species abundance in elderly compared to young subjects.


Asunto(s)
Bacterias/clasificación , Farmacorresistencia Bacteriana , Redes y Vías Metabólicas , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN/métodos , Actinobacteria/aislamiento & purificación , Adulto , Factores de Edad , Anciano , Bacterias/genética , Bacterias/aislamiento & purificación , China , ADN Bacteriano/genética , ADN Ribosómico/genética , Heces/microbiología , Femenino , Microbioma Gastrointestinal , Voluntarios Sanos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Filogenia , Proyectos Piloto , Adulto Joven
12.
Soft Matter ; 17(47): 10753-10764, 2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34792079

RESUMEN

The structural relaxation slows down drastically upon approaching the glass transition, accompanied by the significant growth of dynamic heterogeneity. The fundamental question of elusiveness and interest is whether there exists an underlying quantitative relationship between structural relaxation and dynamic heterogeneity. Here, we reveal that b̃ which is related to the reduced mean square displacements to overcome the energy barriers of activated jumps, instead of the kinetic fragility m, is the genuine key parameter connecting dynamic heterogeneity with structural relaxation for varying types of glass formers. Furthermore, based on the dependence of dynamic heterogeneity on the Debye-Waller factor we obtained a direct quantitative relation between dynamic heterogeneity and structural relaxation is built for different glass-forming liquids. More importantly, a scaling collapse of structural relaxation and dynamic heterogeneity is achieved by the important parameter b̃. These results are of fundamental and critical importance for developing a unified theory of glassy dynamics.

13.
Arch Psychiatr Nurs ; 35(2): 172-177, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33781396

RESUMEN

BACKGROUND: The COVID-19 pandemic seriously endangers the public's mental health, especially to pregnant and postpartum women. But little is known about postpartum depression and health care needs among Chinese postpartum women. AIM: To investigate the status and risk factors of postpartum depression and health care needs among Chinese postpartum women during the COVID-19 pandemic. METHODS: In this cross-sectional study, 209 Chinese postpartum women were recruited from May to July 2020 by convenience sampling and assessed online with self-designed Maternal General Information Questionnaire, Edinburgh Postpartum Depression Scale (EPDS) and Chinese Version of the Perceived Stress Scale (CPSS). Descriptive statistics, chi-square test, independent samples t-test, one-way ANOVA, Pearson correlation and multiple linear regression were used for data analysis. RESULTS: With the EPDS cut-off value of 10, the incidence of postpartum depressive symptoms was 56.9%. Age, history of abortion and perceived stress were the influencing factors of postpartum depression (adjusted R2 = 0.432, F = 23.611, p < .001). The top three health care needs were infant rearing guidance (78.0%), maternal and infant protection guidance (60.3%) and dietary guidance (45.0%). The proportion of psychological rehabilitation guidance needs in the depressed group was significantly higher than that in the non-depressed group (34.5% vs. 20.0%, p < .05). CONCLUSIONS: Maternal postpartum depression in China was at a high level during the COVID-19 pandemic. Women aged 25-34, with a history of abortion and high stress levels were at higher risk for postpartum depression. Timely psychological counselling, intervention and COVID-19-related health education are in great need for postpartum women.


Asunto(s)
COVID-19/psicología , Depresión Posparto/epidemiología , Necesidades y Demandas de Servicios de Salud , Complicaciones del Embarazo/epidemiología , Adulto , China/epidemiología , Estudios Transversales , Femenino , Humanos , Incidencia , Embarazo , Escalas de Valoración Psiquiátrica , Factores de Riesgo , SARS-CoV-2 , Encuestas y Cuestionarios
14.
Phys Chem Chem Phys ; 22(14): 7160-7164, 2020 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-32227015

RESUMEN

Two-dimensional ferroelectric materials can maintain stable polarization with atomic layer thickness, and they have a wide range of technological applications in transistors, resistive memories, energy collectors and other multi-functional sensors for highly integrated flexible electronics. Domain evolution should be considered when 2d ferroelectric material-based devices are applied in a radiation environment, which may induce radiation damage and performance degradation. In this work, we investigate the domain evolution and photodetection performance degradation of α-In2Se3 nanoflakes induced by the total dose effect of 60Co γ-rays. The phonon modes change with an increase in total dose, while the domain structure changes in α-In2Se3 based transistors. Domain evolution may be one of the main reasons for the photoresponsivity degradation of these transistors. This investigation can provide a solid base for future research, and immediate applications in 2d ferroelectric material-based devices can be contemplated.

15.
Phys Chem Chem Phys ; 22(28): 15799-15804, 2020 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-32643733

RESUMEN

The discovery of layered two-dimensional (2D) ferroelectric materials has promoted the development of miniaturized and highly integrated ferroelectric electronics. The 2D ferroelectric materials can be applied in a radiation environment, in which the effect of radiation on these materials should be considered. However, the effects of radiation on 2D ferroelectric materials may be entirely different from those on traditional ferroelectric materials. Ionization effect-induced domain switching can be recovered by applying an external electric field, whereas the displacement effect initiated by radiation particles produces crystal structure damage. The displacement damage that is extremely difficult to recover may have a negative impact on the application of 2D ferroelectric materials in a radiation environment. In this study, the effect of displacement induced by neutron irradiation on the promising α-In2Se3 nanoflakes was investigated. Neutron irradiation (1 MeV) with a fluence of 1014 cm-2 was used for avoiding ionization effects in a certain range. Although the topography of α-In2Se3 does not change underneutron irradiation, vacancies have been proved to be induced by neutron irradiation; furthermore, it has been identified that the vacancies mostly originate from the loss of In atoms. The out-of-plane (OOP) and in-plane (IP) domain structures of the α-In2Se3 nanoflakes with a few layers only slighlty change. In addition, the polarization of the irradiated nanoflakes could still be reversed. All these findings show that although the vacancies may influence the band structure and polarizaiton values of α-In2Se3, the ferroelectric performance may have a strong resistance to neutron irradiation. Therefore, our investigation implies that α-In2Se3 is an excellent 2D ferroelectric material for application in radiation-resistant electronic devices in the future.

16.
BMC Nephrol ; 21(1): 528, 2020 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-33276741

RESUMEN

BACKGROUND: Idiopathic multicentric Castleman disease (iMCD) is an uncommon lymphoproliferative disorder and lacks treatment consensus. Herein, we report a case of iMCD complicated with Sjögren's syndrome (SS) and secondary membranous nephropathy (SMN). CASE PRESENTATION: A 45-year-old female with dry mouth for 3 months and anasarca and proteinuria for 2 months was admitted. She also experienced chest tightness, wheezing, fever, weight loss, moderate proteinuria and hypoalbuminemia. A computed tomography (CT) scan revealed a tissue mass in the thymus area and enlarged multiple lymph nodes. Her symptoms did not improve after resection of the thymus mass. The pathological findings were "reactive hyperplasia of the mediastinal lymph nodes and thymic hyperplasia". Lymph node biopsy findings confirmed iMCD with human herpes virus-8 (HHV-8) negativity. Based on anti-nuclear antibody (ANA) 1:320, anti-SSA and anti-SSB antibody positivity, salivary flow less than 0.1 ml/min and lip biopsy with focal lymphocytic sialadenitis, SS was diagnosed. Kidney biopsy showed secondary membranous nephropathy with endocapillary cell proliferation and infiltration of plasma cells and lymphocytes in the tubulointerstitium. Serum interleukin-6 (IL-6) levels were significantly increased, and therapy with tocilizumab (anti-IL-6 receptor antibody) worked well. The combination of cyclophosphamide (CyS) with methylprednisolone (MP) maintained satisfactory remission. CONCLUSIONS: Our case of iMCD with SS and SMN is rare. There is a need for increased awareness of the disease to avoid unnecessary procedures and misdiagnoses. IL-6 was extremely high, and there was a rapid response to anti-IL-6 receptor agents. The combination of CyS with MP maintained complete remission.


Asunto(s)
Enfermedad de Castleman/patología , Glomerulonefritis Membranosa/patología , Síndrome de Sjögren/inmunología , Anticuerpos Antinucleares/inmunología , Anticuerpos Monoclonales Humanizados/uso terapéutico , Enfermedad de Castleman/complicaciones , Enfermedad de Castleman/tratamiento farmacológico , Ciclofosfamida/uso terapéutico , Errores Diagnósticos , Femenino , Glomerulonefritis Membranosa/tratamiento farmacológico , Glomerulonefritis Membranosa/etiología , Glucocorticoides/uso terapéutico , Humanos , Inmunosupresores/uso terapéutico , Interleucina-6/inmunología , Quimioterapia de Mantención , Metilprednisolona/uso terapéutico , Persona de Mediana Edad , Inducción de Remisión , Síndrome de Sjögren/complicaciones , Síndrome de Sjögren/tratamiento farmacológico , Hiperplasia del Timo/complicaciones , Hiperplasia del Timo/patología , Neoplasias del Timo/diagnóstico
17.
Ren Fail ; 42(1): 829-835, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32787649

RESUMEN

BACKGROUND: Given the important role of Sphingosine-1-phosphate (S1P) in maintaining the hemostasis in intestinal barrier function and regulation of inflammation and immune, we hypothesize that S1P might be a biomarker to predict peritonitis in peritoneal dialysis (PD) patients. METHODS: In this case-control study, 78 stable, continuous ambulatory peritoneal dialysis patients were enrolled and followed for the episode of PD associated peritonitis. Patients were divided into two groups by whether or not they had peritonitis during follow-up: non-peritonitis (n = 65) and peritonitis (n = 13) group. S1P was analyzed by enzyme-linked immunosorbent assay. Logistic regression analysis was used to assess factors associated with peritonitis. The variables identified by univariable regression models (p < 0.1) were further selected into the multivariable logistic regression model to determine whether they could independently affect peritonitis. RESULTS: Patients with peritonitis had a lower level of S1P than that of patients without peritonitis (1.3 ng/mL IQ 0.8, 3.6 ng/mL vs. 2.8 ng/mL IQ 1.5, 5.4 ng/mL, p = 0.018). The peritonitis group had lower serum albumin, lower blood leukocyte, lower hemoglobin and lower platelet count as compared to the non-peritonitis group. Logistic regression analysis showed that S1P (OR = 0.381, 95% CI = 0.171-0.848, p = 0.018), blood leukocyte count (OR = 0.438, 95% CI = 0.207-0.925, p = 0.030), and serum albumin (OR = 0.732, 95% CI = 0.556-0.962, p = 0.025) were independent factors associated with peritonitis in the present PD population. CONCLUSION: Our study showed that S1P was an independent determinant of subsequent peritonitis in PD patients. S1P might serve as a biomarker to predict peritonitis in PD patients.


Asunto(s)
Lisofosfolípidos/sangre , Diálisis Peritoneal Ambulatoria Continua/efectos adversos , Peritonitis/sangre , Esfingosina/análogos & derivados , Anciano , Biomarcadores/sangre , Estudios de Casos y Controles , Femenino , Humanos , Recuento de Leucocitos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Peritonitis/etiología , Factores de Riesgo , Albúmina Sérica/análisis , Esfingosina/sangre
18.
Molecules ; 25(9)2020 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-32392823

RESUMEN

Brevicoryne brassicae is a problematic pest in cabbage and other field crops. Synthetic pesticides are used to control this pest, but they are injurious for human health and the environment. The present study aimed to purify and identify the active compounds from Citrullus colocynthis leaves with an appraisal of their efficacy against B. brassicae. Separation and purification were performed via different chromatographic techniques. Molecular analysis and chemical structures were recognized by mass spectrum (MS) and nuclear magnetic resonance (NMR), respectively. Moreover, in vitro and in vivo aphicidal activity was assessed using various concentrations, i.e., 6.25, 12.5, 25 and 50 µg/mL at 12, 24, 48 and 72 h exposure. The outcome shows that mass spectrum analyses of the purified compounds suggested the molecular formulae are C30H50O and C29H50O, C29H48O. The compounds were characterized as fernenol and a mixture of spinasterol, 22,23-dihydrospinasterol by 1H-NMR and 13C-NMR spectrum analysis. The toxicity results showed that the mixture of spinasterol and 22,23-dihydrospinasterol showed LC50 values of 32.36, 44.49 and 37.50 µg/mL by contact, residual and greenhouse assay at 72 h exposure, respectively. In contrast, fernenol recorded LC50 values as 47.99, 57.46 and 58.67 µg/mL, respectively. On the other hand, spinasterol, 22,23-dihydrospinasterol showed the highest mortality, i.e., 66.67%, 53.33% and 60% while, 30%, 23.33% and 25% mortality was recorded by fernenol after 72 h at 50 µg/mL by contact, residual and greenhouse assay, respectively. This study suggests that spinasterol, 22,23-dihydrospinasterol are more effective against B. brassicae which may be introduced as an effective and suitable substitute of synthetic chemical pesticides.


Asunto(s)
Áfidos/efectos de los fármacos , Citrullus colocynthis/química , Insecticidas/toxicidad , Hojas de la Planta/química , Sitoesteroles/toxicidad , Estigmasterol/análogos & derivados , Triterpenos/toxicidad , Animales , Insecticidas/análisis , Insecticidas/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/toxicidad , Sitoesteroles/análisis , Sitoesteroles/química , Sitoesteroles/aislamiento & purificación , Estigmasterol/análisis , Estigmasterol/química , Estigmasterol/aislamiento & purificación , Estigmasterol/toxicidad , Triterpenos/análisis , Triterpenos/química , Triterpenos/aislamiento & purificación
19.
J Chem Inf Model ; 59(5): 2009-2025, 2019 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-30920827

RESUMEN

In the present work, we develop a coarse-grained (CG) model for polyimide (PI) at 800 K and 1 atm by applying iterative Boltzmann inversion (IBI) and the density correction method to derive the bonded and nonbonded interaction potentials. Although the CG force field is built at a single thermodynamic state point without any temperature correction, the CG model possesses a rather favorable temperature transferability in a wide temperature range of 300-800 K at P = 1 atm and a good pressure transferability to some extent in a certain pressure range from 0.1 to 30 MPa. In addition to the local conformation and local packing distribution functions, the thermodynamic properties such as the glass transition temperature and the coefficient of linear thermal expansion are predicted correctly by the CG model, and the isothermal compressibility coefficients calculated from both atomic and CG models are on the same order of magnitude. Additionally, the stress-strain behavior under compression or tension of the CG model shows a qualitative agreement with the atomistic results, and the corresponding values of the elastic modulus of the CG model at different temperatures roughly match with those of the atomistic model.


Asunto(s)
Imidas/química , Fenómenos Mecánicos , Polímeros/química , Conformación Molecular , Simulación de Dinámica Molecular , Temperatura
20.
J Emerg Med ; 57(6): 791-797, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31708310

RESUMEN

BACKGROUND: Heat stroke is a life-threatening syndrome that is characterized by its severe clinical symptoms, rapid progression, and high rate of mortality. Recently, research has indicated that a dysfunctional intestinal epithelia barrier plays an important role in the pathophysiology of heat stroke. Protecting the intestines from heat stress had been identified as a potentially effective treatment for patients with heat stroke and may reduce the innate immune response caused by endotoxins in circulation. OBJECTIVES: The aim of this review is to discuss this key event in heat stroke and to describe the mechanism during progression. DISCUSSION: Direct injuries and secondary impairments of the intestine induced by heat stress are discussed; recent studies that refer to intestine-specific prevention and treatment in heat stroke and heat stress-induced injuries are also summarized. CONCLUSIONS: A more detailed pathogenesis of heat stroke needs to be elucidated so that potentially effective means of treatment and prevention of heat stroke can be developed and studied.


Asunto(s)
Golpe de Calor/complicaciones , Intestinos/lesiones , Endotoxinas/efectos adversos , Golpe de Calor/fisiopatología , Humanos , Intestinos/fisiopatología , Membrana Mucosa/microbiología , Membrana Mucosa/fisiopatología
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