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1.
Small ; 20(10): e2306344, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37875719

RESUMO

The coupling of photocatalytic hydrogen production and selective oxidation of benzylamine is a topic of significant research interest. However, enhancing the bifunctional photocatalytic activity in this context is still a major challenge. The construction of Z-scheme heterojunctions is an effective strategy to enhance the activity of bifunctional photocatalysts. Herein, a p-n type direct Z-scheme heterojunction CuS/TiO2 is constructed using metal-organic framework (MOF)-derived TiO2 as a substrate. The carrier density is measured by Mott-Schottky under photoexcitation, which confirms that the Z-scheme electron transfer mode of CuS/TiO2 is driven by the diffusion effect caused by the carrier concentration difference. Benefiting from efficient charge separation and transfer, photogenerated electrons, and holes are directedly transferred to active oxidation and reduction sites. CuS/TiO2 also exhibits excellent bifunctional photocatalytic activity without noble metal cocatalysts. Among them, the H2 evolution activity of the CuS/TiO2 is found to be 17.1 and 29.5 times higher than that of TiO2 and CuS, respectively. Additionally, the yields of N-Benzylidenebenzylamine (NBB) are 14.3 and 47.4 times higher than those of TiO2 and CuS, respectively.

2.
Cardiology ; 149(1): 40-50, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37944497

RESUMO

INTRODUCTION: To study the prognostic factors of patients with chest pain and without obstructive coronary artery disease is of great significance for the management of such patients. We assessed whether a high-sensitivity troponin I (hs-TnI) is associated with prognosis in patients with chest pain and without obstructive coronary artery disease. METHODS: From 2011 to 2017, 489 consecutively hospitalized patients with chest pain and without significant coronary artery stenosis (<50%) were tested for hs-TnI and underwent stress myocardial contrast echocardiography (MCE). Myocardial blood flow reserve (MBFR) was measured by stress MCE. Patients were followed (median, 41 months) for composite endpoints, including cardiovascular death and non-fatal myocardial infarction. Cox proportional hazards models were performed to determine associations between hs-TnI and the composite endpoints. RESULTS: Among 489 patients with chest pain and without significant coronary artery stenosis, 257 patients (52.6%) had elevated hs-TnI. Compared to patients with normal hs-TnI, patients with elevated hs-TnI were older (p = 0.013) and had a higher prevalence of atrial fibrillation (p = 0.003), higher left ventricular mass index (p = 0.002) and E/e' septal (p < 0.001), and a lower MBFR (p < 0.001). After adjustment, there was still a significant association between hs-TnI and MBFR (odds ratio = 1.145; 95% confidence interval [CI], 1.079-1.214; p < 0.001). Compared with patients with normal hs-TnI, patients with elevated hs-TnI had a greater cumulative event rate (log-rank p = 0.002). Males (hazard ratio [HR], 4.770; 95% CI, 1.175-19.363; p = 0.029) and reduced MBFR (HR, 2.496; 95% CI, 1.446-4.311; p = 0.001) were risk factors associated with composite endpoints in patients with elevated hs-TnI. CONCLUSIONS: In patients with chest pain and without obstructive coronary artery disease, elevated hs-TnI is associated with decreased myocardial perfusion by contrast echocardiography as well as a higher incidence of cardiovascular events.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Infarto do Miocárdio , Masculino , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Infarto do Miocárdio/epidemiologia , Prognóstico , Troponina I , Estenose Coronária/diagnóstico por imagem , Dor no Peito/etiologia , Biomarcadores
3.
BMC Psychiatry ; 24(1): 210, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500067

RESUMO

BACKGROUND: Current research has been focusing on non-suicidal self-injury (NSSI) behaviors among adolescents with depression. Although family intimacy and adaptability are considered protective factors for NSSI, evidence supporting this relationship is lacking. OBJECTIVE: This study aims to examine the mechanisms operating in the relationship between family intimacy and adaptability and NSSI behaviors among adolescents. METHODS: A self-administered general demographic information questionnaire, the Behavioral Functional Assessment Scale for Non-Suicidal Self-Injury, the Family Intimacy and Adaptability Scale, the Connor-Davidson Resilience Scale, and the Self-Assessment of Depression Scale were distributed among adolescents with depression in three tertiary hospitals in Jiangsu Province. RESULTS: The relationship between family intimacy and adaptability and NSSI was assessed among 596 adolescents with depression. The results revealed the following: (1) Family intimacy and adaptability were negatively correlated with NSSI behavior. (2) Psychological resilience and depression levels acted as chain mediators in the relationship between family intimacy and adaptability and NSSI behavior. CONCLUSIONS: Enhancing psychological resilience, controlling depressive symptoms, and reducing depression severity among adolescents by improving their family intimacy and adaptability are conducive to preventing and mitigating their NSSI behaviors.


Assuntos
Resiliência Psicológica , Comportamento Autodestrutivo , Adolescente , Humanos , Análise de Mediação , Comportamento Autodestrutivo/psicologia , Testes Psicológicos
4.
BMC Ophthalmol ; 24(1): 11, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182979

RESUMO

PURPOSE: The clinical aspects and prognosis of eyes with endogenous endophthalmitis were compared over the last ten years. The occurrence and progression of endophthalmitis are linked to the systemic immune inflammation index (SII) and clinical features. METHODS: The study comprised patients with endogenous endophthalmitis and 64 patients without endophthalmitis who were treated at Hebei Province Eye Hospital in the last ten years. According to the prognostic visual acuity, patients with endophthalmitis were split into two groups: Group A and Group B. Underlying disease (hypertension, diabetes, tuberculosis), infection risk (liver abscess, urinary tract infection, and recent abdominal surgery), signs and symptoms, and complete blood count were among the evaluation parameters (neutrophil count, lymphocyte count, monocyte count, platelet count, red blood cell distribution width). The NLR, PLR, MLR, and SII values were calculated. A nonparametric test was used to examine the clinical features and complete blood count results of patients in each group. To determine the parameters linked to endophthalmitis progression, researchers used principal component and ordinal logistic regression analyses. RESULTS: The study comprised a total of 25 eyes and 22 individuals with endogenous endophthalmitis. Infectious bacteria included Staphylococcus aureus, Micrococcus luteus, Staphylococcus hemolyticus, and so on. The visual acuity of the affected eye ranged from 2.7 (1.55, 2.7) LogMAR to 1.22 (0.6, 2.7) LogMAR during the 6-month to 8-year follow-up period. The neutrophil, monocyte, and PLT counts, NLR, PLR, and SII values and other markers were considerably higher in Groups A and B than in the control group. The likelihood model of the SII and sex, age, onset time, diabetes, hypertension, monocyte count, and red blood cell distribution was the best, and its increase was strongly connected with the occurrence and progression of endophthalmitis, according to ordinal regression analysis. CONCLUSION: Patients with endophthalmitis had significantly higher blood neutrophil, monocyte, and PLT counts and SII, NLR, PLR, and MLR values. The SII can be employed as a biomarker for predicting endophthalmitis severity and prognosis.


Assuntos
Diabetes Mellitus , Endoftalmite , Hipertensão , Humanos , Endoftalmite/diagnóstico , Inflamação , Olho
5.
BMC Musculoskelet Disord ; 25(1): 263, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570738

RESUMO

BACKGROUND: Patients with idiopathic scoliosis commonly present with an imbalance of the paraspinal muscles. However, it is unclear whether this muscle imbalance is an underlying cause or a result of idiopathic scoliosis. This study aimed to investigate the role of paraspinal muscles in the development of idiopathic scoliosis based on surface electromyography (sEMG) and radiographic analyses. METHODS: This was a single-center prospective study of 27 patients with single-curve idiopathic scoliosis. Posteroanterior whole-spine radiographs and sEMG activity of the erector spinae muscles were obtained for all patients in the habitual standing position (HSP), relaxed prone position (RPP), and prone extension position (PEP). The Cobb angle, symmetrical index (SI) of the sEMG activity (convex/concave), and correlation between the two factors were analyzed. RESULTS: In the total cohort, the mean Cobb angle in the HSP was significantly greater than the mean Cobb angle in the RPP (RPP-Cobb) (p < 0.001), whereas the mean Cobb angle in the PEP (PEP-Cobb) did not differ from the RPP-Cobb. Thirteen patients had a PEP-Cobb that was significantly smaller than their RPP-Cobb (p = 0.007), while 14 patients had a PEP-Cobb that was significantly larger than their RPP-Cobb (p < 0.001). In the total cohort and two subgroups, the SI of sEMG activity at the apex vertebra (AVSI) in the PEP was significantly greater than 1, revealing significant asymmetry, and was also significantly larger than the AVSI in the RPP. In the RPP, the AVSI was close to 1 in the total cohort and two subgroups, revealing no significant asymmetry. CONCLUSION: The coronal Cobb angle and the SI of paraspinal muscle activity in AIS patients vary with posture changes. Asymmetrical sEMG activity of the paraspinal muscles may be not an inherent feature of AIS patients, but is evident in the challenging tasks. The potential significance of asymmetric paraspinal muscle activity need to be explored in further research.


Assuntos
Cifose , Escoliose , Humanos , Adolescente , Escoliose/diagnóstico por imagem , Eletromiografia , Músculos Paraespinais/diagnóstico por imagem , Estudos Prospectivos , Coluna Vertebral
6.
BMC Biol ; 21(1): 161, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37480118

RESUMO

BACKGROUND: Pennisetum giganteum (AABB, 2n = 4x = 28) is a C4 plant in the genus Pennisetum with origin in Africa but currently also grown in Asia and America. It is a crucial forage and potential energy grass with significant advantages in yield, stress resistance, and environmental adaptation. However, the mechanisms underlying these advantageous traits remain largely unexplored. Here, we present a high-quality genome assembly of the allotetraploid P. giganteum aiming at providing insights into biomass accumulation. RESULTS: Our assembly has a genome size 2.03 Gb and contig N50 of 88.47 Mb that was further divided into A and B subgenomes. Genome evolution analysis revealed the evolutionary relationships across the Panicoideae subfamily lineages and identified numerous genome rearrangements that had occurred in P. giganteum. Comparative genomic analysis showed functional differentiation between the subgenomes. Transcriptome analysis found no subgenome dominance at the overall gene expression level; however, differentially expressed homoeologous genes and homoeolog-specific expressed genes between the two subgenomes were identified, suggesting that complementary effects between the A and B subgenomes contributed to biomass accumulation of P. giganteum. Besides, C4 photosynthesis-related genes were significantly expanded in P. giganteum and their sequences and expression patterns were highly conserved between the two subgenomes, implying that both subgenomes contributed greatly and almost equally to the highly efficient C4 photosynthesis in P. giganteum. We also identified key candidate genes in the C4 photosynthesis pathway that showed sustained high expression across all developmental stages of P. giganteum. CONCLUSIONS: Our study provides important genomic resources for elucidating the genetic basis of advantageous traits in polyploid species, and facilitates further functional genomics research and genetic improvement of P. giganteum.


Assuntos
Pennisetum , Pennisetum/genética , Biomassa , Genoma de Planta , Poliploidia , Perfilação da Expressão Gênica
7.
Opt Express ; 31(6): 9886-9903, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37157549

RESUMO

A compressive space-dimensional dual-coded hyperspectral polarimeter (CSDHP) and interactive design method are introduced. A digital micromirror device (DMD), a micro polarizer array detector (MPA), and a prism grating prism (PGP) are combined to achieve single-shot hyperspectral polarization imaging. The longitudinal chromatic aberration (LCA) and spectral smile of the system are both eliminated to guarantee the matching accuracy of DMD and MPA pixels. A 4D data cube with 100 channels and 3 Stocks parameters is reconstructed in the experiment. The feasibility and fidelity are verified from the image and spectral reconstruction evaluations. It is demonstrated that the target material can be distinguished by CSDHP.

8.
Opt Express ; 31(19): 30750-30766, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710612

RESUMO

Polarized remote sensing imaging has attracted more attention in recent years due to its wider detection information dimension compared to traditional imaging methods. However, the inherent instrument errors in optical systems can lead to errors in the polarization state of the incident and outgoing light, which is the polarization aberration of the optical system, resulting in a decrease in polarization detection accuracy. We propose a polarization aberration simplification calculation method for planar symmetric optical systems, by what only three ray samples are needed to obtain the distribution of polarization aberrations within the pupil. This method has a calculation accuracy close to traditional methods, and the sampling rate is 0.003 times that of traditional methods. Based on this, we designed a merit function that optimizes both wavefront and polarization aberrations simultaneously. It is found that diattenuation and retardance of the optical system are 62% and 58% of the original, and the polarization crosstalk term is reduced by 37% when the polarization weight factor takes an appropriate value. And at the same time, the wavefront aberration has also been well optimized.

9.
Phys Rev Lett ; 131(18): 186703, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37977650

RESUMO

The understanding and manipulation of anisotropic Gilbert damping is crucial for both fundamental research and versatile engineering and optimization. Although several works on anisotropic damping have been reported, no direct relationship between the band structure and anisotropic damping was established. Here, we observed an anisotropic damping in Fe/GeTe manipulated by the symmetric band structures of GeTe via angle-resolved photoemission spectroscopy. Moreover, the anisotropic damping can be modified by the symmetry of band structures. Our Letter provides insightful understandings of the anisotropic Gilbert damping in ferromagnets interfaced with Rashba semiconductors and suggests the possibility of manipulating the Gilbert damping by band engineering.

10.
BMC Ophthalmol ; 23(1): 389, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752454

RESUMO

BACKGROUND: Stellate nonhereditary idiopathic foveomacular retinoschisis (SNIFR) is a rare type of retinoschisis with a spoke-like splitting that occurs in the outer plexus layer. We present a case of stellate nonhereditary idiopathic foveomacular retinoschisis in a juvenile, in which two eyes show different development trends and macular retinoschisis could be associated with mechanical force in the Henle fibre layer. The removal of mechanical force can partially restore vision. CASE PRESENTATION: A 14-year-old girl with bilateral SNIFR was diagnosed and followed up with spectral-domain optical coherence tomography (SD-OCT). During the two follow-up visits, vitreous adhesion was released in the left eye, and visual acuity improved. Neuroepithelial detachment was aggravated in the right eye, and visual acuity decreased. Therefore, vitrectomy was performed on the right eye. After surgery, the patient's retina was reattached, and her vision was partially restored. CONCLUSIONS: We reported a juvenile with bilateral SNIFR. Each of her eyes showed different development trends, so we adopted different treatment methods for each eye. Vitrectomy was performed on the patient to address progressive vision loss, which improved the patient's vision. It was further confirmed that the Henle layer of SNIFR patients was susceptible to posterior vitreous membrane adhesion.


Assuntos
Degeneração Macular , Retinosquise , Humanos , Feminino , Adolescente , Retinosquise/diagnóstico , Retina , Vitrectomia , Corpo Vítreo
11.
J Integr Plant Biol ; 65(6): 1423-1441, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36680412

RESUMO

Common buckwheat (Fagopyrum esculentum) and Tartary buckwheat (Fagopyrum tataricum), the two most widely cultivated buckwheat species, differ greatly in flavonoid content and reproductive mode. Here, we report the first high-quality and chromosome-level genome assembly of common buckwheat with 1.2 Gb. Comparative genomic analysis revealed that common buckwheat underwent a burst of long terminal repeat retrotransposons insertion accompanied by numerous large chromosome rearrangements after divergence from Tartary buckwheat. Moreover, multiple gene families involved in stress tolerance and flavonoid biosynthesis such as multidrug and toxic compound extrusion (MATE) and chalcone synthase (CHS) underwent significant expansion in buckwheat, especially in common buckwheat. Integrated multi-omics analysis identified high expression of catechin biosynthesis-related genes in flower and seed in common buckwheat and high expression of rutin biosynthesis-related genes in seed in Tartary buckwheat as being important for the differences in flavonoid type and content between these buckwheat species. We also identified a candidate key rutin-degrading enzyme gene (Ft8.2377) that was highly expressed in Tartary buckwheat seed. In addition, we identified a haplotype-resolved candidate locus containing many genes reportedly associated with the development of flower and pollen, which was potentially related to self-incompatibility in common buckwheat. Our study provides important resources facilitating future functional genomics-related research of flavonoid biosynthesis and self-incompatibility in buckwheat.


Assuntos
Fagopyrum , Flavonoides , Flavonoides/metabolismo , Fagopyrum/genética , Fagopyrum/metabolismo , Rutina/análise , Rutina/metabolismo , Genes de Plantas , Sementes/genética
12.
BMC Oral Health ; 23(1): 1016, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38115040

RESUMO

BACKGROUND: In the period of the early implant placement, the socket is mainly occupied by provisional matrix (PM). Keratinized epithelium (KE) is critical for primary wound closure. Although both KE and PM are important, the detailed relationship among migrating KE, PM formation and indication of the early implant placement is still unclear. OBJECTIVE: This research aimed to locate a healing stage of KE with highest osteogenic PM formation after tooth extraction, which could be treated as the optimal time point for early implant placement. MATERIAL AND METHODS: Mice were sacrificed on days 1, 2, 3, 4 and 6 after incisor extraction. Clinical, histological, and immunohistochemical evaluations of the extraction sockets were performed, and statistical analyses were conducted. We then inserted implants into the PM with the greatest bioactivity and observed its osseointegration pattern for 3, 10, 17 and 30 days. RESULT: When KE fusion was reached, sockets were dominated by PM with the greatest expression of osteocalcin (OC, P < 0.05) and high levels of CD34 and Runx2. OC and Runx2 expression were positively correlated with KE coverage (P < 0.05). When the implant was inserted at 4 days' healing, the PM maintained its osteogenic ability, and osseointegration proceeded perfectly. CONCLUSION: The migration of KE was correlated with the formation of highly osteogenic and angiogenic PM. And the fusion of KE could be treated as an indication for early implant placement.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Animais , Camundongos , Subunidade alfa 1 de Fator de Ligação ao Core , Alvéolo Dental/cirurgia , Estética Dentária , Osseointegração , Extração Dentária
13.
Appl Opt ; 61(21): 6330-6338, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-36256248

RESUMO

The marine environment is complex and changeable. To meet the urgent needs of accurate detection and identification of oil spills, a visible/infrared dual-band common-aperture polarization imaging optical system based on a defocused plane polarization detector is designed. The optical system is evaluated by ZEMAX simulation software, and we carried out the polarization imaging oil species discrimination experiment based on the split focal plane polarization detector, which proved that for some oil species that cannot be distinguished by intensity information, the polarization information can be distinguished. It verifies the feasibility of polarization detection in the discrimination of marine oil spills, which is of great practical significance in the field of marine oil spill detection.


Assuntos
Dispositivos Ópticos , Poluição por Petróleo
14.
BMC Musculoskelet Disord ; 23(1): 1074, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36476222

RESUMO

BACKGROUND: Previous studies have investigated the imaging changes of the paravertebral muscles (PVM) in patients with degenerative lumbar scoliosis (DLS); however, most of these studies focused on the apical vertebra (AV) level or compared with the average of the whole-segment measurement. In this study, magnetic resonance imaging (MRI) combined with surface electromyography (sEMG) was used to analyze the degenerative characteristics of the multifidus (MF) in patients with DLS at three levels of scoliosis (upper end vertebra [UEV], AV, and lower end vertebra [LEV]). METHODS: This is a prospective cross-sectional study. Forty patients with DLS (DLS group) and 40 healthy individuals without lumbar scoliosis (control group) were evaluated. The percentage of fat infiltration area (%FIA) and muscle relative cross-sectional area (rCSA) of the MF at the three levels of scoliosis were measured on MRI, whereas the sEMG activity of the participants in both groups was recorded during action tasks. The imaging parameters, sEMG activity, and relationship between them were analyzed. RESULTS: In the control group, there were no significant differences in the %FIA, rCSA, or sEMG activation of the MF between the bilateral sides at the three measured levels. In the DLS group, measurement of the MF at the UEV and AV levels showed that the %FIA was larger on the concave than convex side and that the rCSA was smaller on the concave than convex side, but there was no difference between the two parameters at the LEV level. In the standing flexion and extension tasks, the sEMG activation of the MF was higher on the concave than convex side. The coronal Cobb angle was correlated with the difference in the measurement data of the MF at the UEV and AV levels, but not with the difference at the LEV level. CONCLUSION: The MF in patients with DLS has the same degenerative features at the UEV and AV levels, with the concave side showing greater degeneration; however, there are different degenerative manifestations at the LEV level. The MF degeneration at the UEV and AV levels is the result of spinal deformity, while the muscle changes at the LEV level are more consistent with natural degeneration.


Assuntos
Nível de Saúde , Humanos , Eletromiografia , Estudos Transversais , Estudos Prospectivos
15.
Biomed Chromatogr ; 36(2): e5253, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34596250

RESUMO

Saururus chinensis (SC) possesses significant anti-diabetic activity and lignans were its major bioactive compounds. In this study, a rapid and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was established for simultaneous quantification of six lignans, namely (-)-(7R,8R)-machilin D (1), verrucesin (2), rel-(7S,8S,7'R,8'R)-3,3',4,4',5,5'-hexamethoxy-7.O.7',8.8'-lignan (3), manassantin A (4), manassantin B (5), and saucerneol F (6) in rat's plasma. It was validated with acceptable linearity (r ≥ 0.9922), accuracy (80.42-95.17%), precision (RSD ≤ 12.08%), and extraction recovery (80.36-93.45%). The method was successfully applied to the comparative pharmacokinetic study of the six lignans in normal and diabetic rats after oral administration of SC extract. Results showed that the areas under the plasma concentration-time curve (AUC0 → t and AUC0 → ∞ ) of (-)-(7R,8R)-machilin D, rel-(7S,8S,7'R,8'R)-3,3',4,4',5,5'-hexamethoxy-7.O.7',8.8'-lignan, manassantin B, and saucerneol F in diabetic rats were significantly increased, and the plasma clearance (CL) of (-)-(7R,8R)-machilin D in diabetic rats was significantly decreased. However, the AUC0 → t and AUC0 → ∞ of verrucesin were significantly decreased, and its CL was significantly increased in diabetic rats compared with those in normal rats. These results indicated that there were remarkable differences in the pharmacokinetic parameters between the normal and diabetic rats. The pharmacokinetic studies might be beneficial for the clinical use of SC as hypoglycemic agent.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Lignanas , Extratos Vegetais , Saururaceae/química , Administração Oral , Animais , Cromatografia Líquida de Alta Pressão/métodos , Lignanas/sangue , Lignanas/química , Lignanas/farmacocinética , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacocinética , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem/métodos
16.
Nano Lett ; 21(1): 77-83, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33263408

RESUMO

Ferroelectric Rashba semiconductors (FERSCs) have recently attracted intensive attention due to their giant bulk Rashba parameter, αR, which results in a locking between the spin degrees of freedom and the switchable electric polarization. However, the integration of FERSCs into microelectronic devices has provoked questions concerning whether the Rashba effect can persist when the material thickness is reduced to several nanometers. Here we find that αR can keep a large value of 2.12 eV Å in the 5.0 nm thick GeTe film. The behavior of αR with thickness can be expressed by the scaling law and provides a 3D thickness limit of the bulk Rashba effect, dc = 2.1 ± 0.5 nm. Finally, we find that the thickness can modify the Berry curvature as well, which influences the polarization and consequently alters the αR. Our results give insight into understanding the factors influencing αR in FERSCs and pave a novel route for designing Rashba-type quantum materials.

17.
Int J Mol Sci ; 23(3)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35163237

RESUMO

Glutaredoxin (Grx) is an important oxidoreductase to maintain the redox homoeostasis of cells. In our previous study, cold-adapted Grx from Psychrobacter sp. ANT206 (PsGrx) has been characterized. Here, we constructed an in-frame deletion mutant of psgrx (Δpsgrx). Mutant Δpsgrx was more sensitive to low temperature, demonstrating that psgrx was conducive to the growth of ANT206. Mutant Δpsgrx also had more malondialdehyde (MDA) and protein carbonylation content, suggesting that PsGrx could play a part in the regulation of tolerance against low temperature. A yeast two-hybrid system was adopted to screen interacting proteins of 26 components. Furthermore, two target proteins, glutathione reductase (GR) and alkyl hydroperoxide reductase subunit C (AhpC), were regulated by PsGrx under low temperature, and the interactions were confirmed via bimolecular fluorescence complementation (BiFC) and co-immunoprecipitation (Co-IP). Moreover, PsGrx could enhance GR activity. trxR expression in Δpsgrx, Δahpc, and ANT206 were illustrated 3.7, 2.4, and 10-fold more than mutant Δpsgrx Δahpc, indicating that PsGrx might increase the expression of trxR by interacting with AhpC. In conclusion, PsGrx may participate in glutathione metabolism and ROS-scavenging by regulating GR and AhpC to protect the growth of ANT206. These findings preliminarily suggest the role of PsGrx in the regulation of oxidative stress, which could improve the low-temperature tolerance of ANT206.


Assuntos
Glutarredoxinas/metabolismo , Psychrobacter/genética , Sequência de Aminoácidos , Antioxidantes/metabolismo , Temperatura Baixa , Glutarredoxinas/fisiologia , Glutationa Redutase/metabolismo , Glutationa Redutase/fisiologia , Homeostase , Cinética , Modelos Moleculares , Oxirredução , Estresse Oxidativo , Peroxirredoxinas/metabolismo , Peroxirredoxinas/fisiologia , Psychrobacter/metabolismo , Temperatura
18.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(8): 809-813, 2022 Aug 10.
Artigo em Zh | MEDLINE | ID: mdl-35929927

RESUMO

Monogenic disorders are varied and complex. Its overall incidence is high and the clinical phenotypes differ greatly, causing disability, mental retardation or death. It is an effective strategy to prevent the birth of newborns with monogenic disorders through prenatal screening and diagnosis. Cell-free fetal DNA based non-invasive prenatal testing for monogenic disorders has been applied in clinical practice. The range of diseases being tested is expanding, and the technology is continuously making breakthroughs. This article has provided a review over the research progress made in this field.


Assuntos
Ácidos Nucleicos Livres , Ácidos Nucleicos Livres/genética , DNA/genética , Feminino , Feto , Humanos , Fenótipo , Gravidez , Diagnóstico Pré-Natal
19.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(11): 1211-1215, 2022 Nov 10.
Artigo em Zh | MEDLINE | ID: mdl-36317205

RESUMO

OBJECTIVE: To investigate the clinical significance of miRNA-146, OX-LDL and ROS in patients with primary ovarian insufficiency (POI). METHODS: 100 patients with POI were prospectively collected and 100 women with normal ovarian function were randomly selected as control group. Serum miRNA-146 expression level was detected by qRT-PCR and serum OX-LDL and ROS expression levels were detected by ELISA. Ovarian granulosa cells of mouse were transfected with miRNA-146 mimics or inhibitors, and then treated with OX-LDL. Cell viability, colony forming ability, apoptosis rate and toll like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) of pathway proteins were evaluated respectively. RESULTS: Compared with control group, the expression level of miRNA-146 in POI group was significantly lower, the expression level of OX-LDL and ROS were significantly higher, and the ovarian volume and peak systolic blood flow velocity of ovarian artery were significantly decreased in POI group. Upregulation of miRNA-146 expression had a protective effect on OX-LDL injured ovarian granulosa cells, as evidenced by increased ovarian granulosa cell viability and colony number, reduced apoptosis, and downregulation of TLR4/NF-κB expression. CONCLUSION: miRNA-146 can target downstream TLR4/NF-κB signaling pathway affects oxidative stress and inflammatory response of POI induced by OX-LDL and ROS, and is expected to become a biomarker for early prediction of POI and a new target for treatment.


Assuntos
MicroRNAs , Insuficiência Ovariana Primária , Humanos , Feminino , Camundongos , Animais , Receptor 4 Toll-Like/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Insuficiência Ovariana Primária/genética , Apoptose/genética
20.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(6): 1181-1188, 2022 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-36575088

RESUMO

Intelligent medical image segmentation methods have been rapidly developed and applied, while a significant challenge is domain shift. That is, the segmentation performance degrades due to distribution differences between the source domain and the target domain. This paper proposed an unsupervised end-to-end domain adaptation medical image segmentation method based on the generative adversarial network (GAN). A network training and adjustment model was designed, including segmentation and discriminant networks. In the segmentation network, the residual module was used as the basic module to increase feature reusability and reduce model optimization difficulty. Further, it learned cross-domain features at the image feature level with the help of the discriminant network and a combination of segmentation loss with adversarial loss. The discriminant network took the convolutional neural network and used the labels from the source domain, to distinguish whether the segmentation result of the generated network is from the source domain or the target domain. The whole training process was unsupervised. The proposed method was tested with experiments on a public dataset of knee magnetic resonance (MR) images and the clinical dataset from our cooperative hospital. With our method, the mean Dice similarity coefficient (DSC) of segmentation results increased by 2.52% and 6.10% to the classical feature level and image level domain adaptive method. The proposed method effectively improves the domain adaptive ability of the segmentation method, significantly improves the segmentation accuracy of the tibia and femur, and can better solve the domain transfer problem in MR image segmentation.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Joelho , Articulação do Joelho
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