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1.
J Synchrotron Radiat ; 31(Pt 1): 10-16, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38010795

RESUMO

X-ray mirrors for synchrotron radiation are often bent into a curved figure and work under grazing-incidence conditions due to the strong penetrating nature of X-rays to most materials. Mirrors of different cross sections have been recommended to reduce the mirror's slope inaccuracy and clamping difficulty in order to overcome mechanical tolerances. With the development of hard X-ray focusing, it is difficult to meet the needs of focusing mirrors with small slope error with the existing mirror processing technology. Deformable mirrors are adaptive optics that can produce a flexible surface figure. A method of using a deformable mirror as a phase compensator is described to enhance the focusing performance of an X-ray mirror. This paper presents an active piezoelectric plane X-ray focusing mirror with a linearly changing thickness that has the ability of phase compensation while focusing X-rays. Benefiting from its special structural design, the mirror can realize flexible focusing at different focusing geometries using a single input driving voltage. A prototype was used to measure its performance under one-dimension and two-dimension conditions. The results prove that, even at a bending magnet beamline, the mirror can easily achieve a single-micrometre focusing without a complicated bending mechanism or high-precision surface processing. It is hoped that this kind of deformable mirror will have a wide and flexible application in the synchrotron radiation field.

2.
Opt Express ; 32(8): 13597-13613, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859326

RESUMO

The hard X-ray nanoprobe beamline is the first beamline to take advantage of the full coherent beam to attain the nanoscale focusing at the Shanghai Synchrotron Radiation Facility (SSRF). Here we introduce the beamline and specially go over the features of the multilayer Kirkpatrick-Baez focusing system and its supporting phase compensator system. The performance and stability of the phase compensator are also put to the test. By using the speckle scanning metrology, the wavefront of a focused beam was characterized and intensity distribution near the focus was reconstructed. The focusing performance was greatly enhanced by two phase compensations based on a global optimization technique, and a two-dimensional focal spot of 26 nm × 17 nm was achieved and maintained with good stability.

3.
J Magn Reson Imaging ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485518

RESUMO

BACKGROUND: Although right atrial (RA) myocardial deformation has important implications for patient diagnosis, prognosis, and risk stratification, its implementation in clinical practice has been hampered by limited normal reference values, especially in Asian populations. PURPOSE: To establish age- and sex-specific reference values for RA strain, strain rate (SR), and displacement based on a large sample of healthy Chinese adults using MR-feature tracking (MR-FT). STUDY TYPE: Retrospective. POPULATION: 524 healthy Chinese adults (287 male; mean age 43.7 ± 11.9 years). FIELD STRENGTH/SEQUENCE: 1.5T/balanced steady-state free precession. ASSESSMENT: RA deformation parameters, including reservoir, conduit, and booster strain (εs, εe, and εa), peak positive, early negative, and late negative SR (SRs, SRe, and SRa), and total, passive, and active displacement (Ds, De, and Da), were assessed using MR-FT. STATISTICAL TESTS: Student's t-test, one-way ANOVA, coefficients of determination (r2 ), intraclass correlation coefficients (ICC), and Bland-Altman plots. A P value <0.05 was considered significant. RESULTS: Women demonstrated significantly greater magnitudes of RA deformation parameters than men: εs (57.4% ± 15.1% vs. 44.3% ± 12.6%), εe (37.5% ± 13.4% vs. 27.4% ± 10.9%), εa (19.9% ± 5.7% vs. 16.9% ± 5.0%), SRs (2.62 ± 0.88 sec-1 vs. 2.00 ± 0.63 sec-1 ), SRe (-2.98 ± 1.26 sec-1 vs. -2.16 ± 0.92 sec-1 ), SRa (-2.28 ± 0.75 sec-1 vs. -1.84 ± 0.62 sec-1 ), Ds (-7.80 ± 1.90 mm vs. -7.46 ± 1.70 mm), and De (-4.84 ± 1.31 mm vs. -4.49 ± 1.21 mm). For both sexes, aging was significantly associated with decreased RA reservoir and conduit function (εs, SRs, Ds, εe, SRe, and De), and with increased εa and Da. RA deformation measurements had good to excellent intraobserver and interobserver reproducibility, with ICCs ranging from to 0.790 to 0.972. DATA CONCLUSION: This study provides age- and sex-specific reference values of RA strain, SR, and displacement based on a large cohort of healthy Chinese adults using MR-FT. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

4.
Nanotechnology ; 35(28)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38579687

RESUMO

Oxygen vacancies and heteroatom doping play important role in oxygen reduction activity of metal oxides. Developing efficient modification method is one of the key issues in catalysts research. Room temperature plasma treatment, with the advantages of mild working conditions, no emissions and high efficiency, is a new catalyst modification method developed in recent years. In this work, hydrothermal synthesizedα-MnO2nanorods are treated in NH3plasma at room temperature. In the reducing atmosphere, oxygen vacancies and N doping are achieved simultaneously on the surface. The NH3plasma etched MnO2demonstrate a significant enhanced oxygen reduction activity with half-wave potential of 0.84 V, limiting current density of 6.32 mA cm-2and transferred electrons number of 3.9. The Mg-air battery with N-MnO2display a maximum power density of 76.3 mW cm-2as well as stable discharge performance. This work provides new ideas for preparing efficient and cost-effective method to boost the catalysts activity.

5.
J Transl Med ; 21(1): 455, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430272

RESUMO

BACKGROUND: In diabetic retinopathy, increasing evidence points to a link between the pathogenesis of retinal microangiopathy and the endothelial cell-specific factor roundabout4 (ROBO4). According to earlier research, specificity protein 1 (SP1) enhances the binding to the ROBO4 promoter, increasing Robo4 expression and hastening the progression of diabetic retinopathy. To determine if this is related to aberrant epigenetic modifications of ROBO4, we examined the methylation level of the ROBO4 promoter and the corresponding regulatory mechanism during the course of diabetic retinopathy and explored the effect of this mechanism on retinal vascular leakage and neovascularization. METHODS: The methylation level of CpG sites in the ROBO4 promoter was detected in human retinal endothelial cells (HRECs) cultured under hyperglycemic conditions and retinas from streptozotocin-induced diabetic mice. The effects of hyperglycemia on DNA methyltransferase 1, Tet methylcytosine dioxygenase 2 (TET2), 5-methylcytosine, 5-hydroxymethylcytosine, and the binding of TET2 and SP1 to the ROBO4 promoter, as well as the expression of ROBO4, zonula occludens 1 (ZO-1) and occludin were examined. Short hairpin RNA was used to suppress the expression of TET2 or ROBO4 and the structural and functional changes in the retinal microvascular system were assessed. RESULTS: In HRECs cultured under hyperglycemic conditions, the ROBO4 promoter methylation level decreased. Hyperglycemia-induced TET2 overexpression caused active demethylation of ROBO4 by oxidizing 5-methylcytosine to 5-hydroxymethylcytosine, which enhanced the binding of SP1 to ROBO4, increased the expression of ROBO4, and decreased the expression of ZO-1 and occludin, leading to the abnormalities in monolayer permeability, migratory ability and angiogenesis of HRECs. The above pathway was also demonstrated in the retinas of diabetic mice, which caused leakage from retinal capillaries and neovascularization. Inhibition of TET2 or ROBO4 expression significantly ameliorated the dysfunction of HRECs and retinal vascular abnormalities. CONCLUSIONS: In diabetes, TET2 can regulate the expression of ROBO4 and its downstream proteins by mediating active demethylation of the ROBO4 promoter, which accelerates the development of retinal vasculopathy. These findings suggest that TET2-induced ROBO4 hypomethylation is a potential therapeutic target, and anti- TET2/ROBO4 therapy is anticipated to emerge as a novel strategy for early intervention and delayed progression of diabetic retinopathy.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Dioxigenases , Hiperglicemia , Animais , Humanos , Camundongos , 5-Metilcitosina , Diabetes Mellitus Experimental/genética , Retinopatia Diabética/genética , Proteínas de Ligação a DNA/genética , Células Endoteliais , Neovascularização Patológica , Ocludina , Receptores de Superfície Celular
6.
Opt Express ; 31(20): 32909-32924, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859083

RESUMO

Serial femtosecond crystallography at X-ray free electron laser facilities opens a new era for the determination of crystal structure. However, the data processing of those experiments is facing unprecedented challenge, because the total number of diffraction patterns needed to determinate a high-resolution structure is huge. Machine learning methods are very likely to play important roles in dealing with such a large volume of data. Convolutional neural networks have made a great success in the field of pattern classification, however, training of the networks need very large datasets with labels. This heavy dependence on labeled datasets will seriously restrict the application of networks, because it is very costly to annotate a large number of diffraction patterns. In this article we present our job on the classification of diffraction pattern by weakly supervised algorithms, with the aim of reducing as much as possible the size of the labeled dataset required for training. Our result shows that weakly supervised methods can significantly reduce the need for the number of labeled patterns while achieving comparable accuracy to fully supervised methods.

7.
J Magn Reson Imaging ; 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38156373

RESUMO

BACKGROUND: The clinical value of myocardial torsion quantification in prognostic assessment and risk stratification of various cardiovascular diseases is gradually being recognized. However, normal values of left and right ventricular (LV and RV) torsion and torsion rates (TRs) have not been fully determined, and their correlation with age and gender has not been well studied. PURPOSE: To establish normal ranges of biventricular torsion, peak systolic and diastolic TRs using magnetic resonance feature tracking (MR-FT) technique based on a large sample of healthy adults, and further investigate their relationship with age and gender. STUDY TYPE: Retrospective. POPULATION: 566 Healthy adults (312 males, aged 43 ± 10 years; 254 females, aged 43 ± 11 years). FIELD STRENGTH/SEQUENCE: 1.5T/gradient echo. ASSESSMENT: Biventricular torsion, peak systolic, and diastolic TRs. STATISTICAL TESTS: Shapiro-Wilk test, Student's t-test, Mann-Whitney-U test, linear regression, intraclass correlation coefficient, Bland-Altman analysis. Differences were regarded as statistically significant at P < 0.05. RESULTS: Women demonstrated greater magnitudes of left ventricle (LV) torsion (1.23 ± 0.44 vs. 1.00 ± 0.42°/cm), peak systolic TR (9.69 ± 3.70 vs. 8.27 ± 3.73°/cm*sec), peak diastolic TR (-7.78 ± 2.82 vs. -6.06 ± 2.44°/cm*sec), and RV torsion (2.20 ± 1.23 vs. 1.65 ± 1.11°/cm*sec), peak systolic TR (16.07 ± 8.18 vs. 12.62 ± 7.08°/cm*sec), peak diastolic TR (-15.39 ± 6.53 vs. -11.70 ± 6.03°/cm*sec). For both genders, the magnitudes of LV and RV torsion, peak systolic, and diastolic TRs increased linearly with age. All the measurements of biventricular torsion, peak systolic and diastolic TRs achieved good to excellent intraobserver and interobserver reproducibility, with all intraclass correlation coefficients >0.70. DATA CONCLUSION: The present study systematically provided age- and sex-stratified reference values for LV and RV torsion and TRs using MR-FT technique. Women and aging are associated with greater magnitudes of biventricular torsion, peak systolic, and diastolic TRs. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

8.
BMC Cardiovasc Disord ; 23(1): 367, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37480020

RESUMO

PURPOSE: This study aims to develop a low-radiation dose, one-step integrated coronary-carotid-cerebral computed tomography angiography (ICCC-CTA) technique to analyze the relationship between cardiovascular and cerebrovascular atherosclerosis and evaluate the risk factors of plaque to provide an early-stage treatment to patients and reduce vascular events. METHODS: A total of 300 consecutive asymptomatic patients with cardiovascular risk factors who underwent ICCC-CTA were enrolled in this prospective study. The association between coronary and carotid-cerebrovascular atherosclerosis was assessed. The primary cardiovascular risk factors for various plaque types in cardiovascular or cerebrovascular disease were evaluated using multivariate analysis. RESULTS: Among 300 patients, 189 (63%) had plaques in their coronary and cerebral arteries. The presence of calcified and mixed plaques in the carotid-cerebral and coronary arteries was strongly correlated (χ2 = 20.71, P = 0.001; χ2 = 8.96, P = 0.003, respectively). Multivariate logistic regression analysis revealed that abnormal blood glucose [OR = 1.44, 95% CI 0.12-0.62, P = 0.01] and abnormal total cholesterol [OR = 1.28, 95% CI 0.07-0.46, P = 0.01] are risk factors in all the models in the coronary artery, non-calcified plaque group. Abnormal blood glucose [OR = 1.43, 95% CI 0.11-0.61, P = 0.01] and abnormal systolic blood pressure [OR = 1.02, 95% CI 0.01-0.04, P = 0.02] are risk factors in all the models in the coronary artery calcified plaque group. Abnormal blood glucose level [OR = 1.44, 95% CI = 0.12-0.62, P = 0.01] was only a risk factor in the non-calcified plaque carotid-cerebral artery group. CONCLUSIONS: We confirm that elevated blood glucose and total cholesterol levels are associated with coronary and carotid-cerebrovascular plaques using the novel one-step low dose cerebral-carotid-cardiac CTA technique. These findings will provide insights for further studies focusing on developing low-radiation dose one-step ICCC-CTA to screen cardiovascular/cerebrovascular plaques in general population with cardiovascular risk factors. ADVANCES IN KNOWLEDGE: We developed a low-radiation dose, one-step ICCC-CTA technique to detect cardiovascular and cerebrovascular atherosclerosis. We evaluated the risk factors for plaque burden for the early treatment and reduction of vascular events. These findings supported the development of low-radiation dose one-step ICCC-CTA to screen for cardiovascular/cerebrovascular disease in general population with cardiovascular risk factors.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Doenças das Artérias Carótidas , Doença da Artéria Coronariana , Placa Aterosclerótica , Humanos , Angiografia por Tomografia Computadorizada/métodos , Estudos Prospectivos , Glicemia , Placa Aterosclerótica/complicações , Doenças das Artérias Carótidas/complicações , Doenças Cardiovasculares/complicações , Fatores de Risco , Colesterol , Angiografia Coronária/efeitos adversos , Doença da Artéria Coronariana/complicações
9.
Sensors (Basel) ; 22(9)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35590896

RESUMO

Herein, we propose a system for a snapshot video hyperspectral imaging method based on a uniformly distributed-slit array (UDA) coding plate that not only effectively improves the scanning speed of spectrometers but also achieves a high spectral fidelity of snapshot videos. A mathematical model and optical link simulation of the new system are established. The analysis results show that the proposed method can more efficiently collect information and restore the spectral data cube, and the spectral smile of the system is less than 4.86 µm. The results of the spectral performance and external imaging tests of the system show that the system has the ability to collect spatial spectrum video information with a frame rate of 10 Hz and identify dynamic targets, laying a foundation for the design of a system with a higher frame rate and resolution.


Assuntos
Diagnóstico por Imagem , Imageamento Hiperespectral , Cintilografia
10.
J Cell Mol Med ; 24(6): 3346-3358, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32003125

RESUMO

Our study aimed to evaluate the protective role and mechanisms of bone marrow mesenchymal stem cells (BMSCs) in hypoxic photoreceptors and experimental retinal detachment. The cellular morphology, viability, apoptosis and autophagy of hypoxic 661w cells and cells cocultured with BMSCs were analysed. In retinal detachment model, BMSCs were intraocularly transplanted, and then, the retinal morphology, outer nuclear layer (ONL) thickness and rhodopsin expression were studied as well as apoptosis and autophagy of the retinal cells. The hypoxia-induced apoptosis of 661w cells obviously increased together with autophagy levels increasing and peaking at 8 hours after hypoxia. Upon coculturing with BMSCs, hypoxic 661w cells had a better morphology and fewer apoptosis. After autophagy was inhibited, the apoptotic 661w cells under the hypoxia increased, and the cell viability was reduced, even in the presence of transplanted BMSCs. In retina-detached eyes transplanted with BMSCs, the retinal ONL thickness was closer to that of the normal retina. After transplantation, apoptosis decreased significantly and retinal autophagy was activated in the BMSC-treated retinas. Increased autophagy in the early stage could facilitate the survival of 661w cells under hypoxic stress. Coculturing with BMSCs protects 661w cells from hypoxic damage, possibly due to autophagy activation. In retinal detachment models, BMSC transplantation can significantly reduce photoreceptor cell death and preserve retinal structure. The capacity of BMSCs to reduce retinal cell apoptosis and to initiate autophagy shortly after transplantation may facilitate the survival of retinal cells in the low-oxygen and nutrition-restricted milieu after retinal detachment.


Assuntos
Hipóxia Celular/fisiologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células Fotorreceptoras Retinianas Cones/citologia , Descolamento Retiniano/patologia , Animais , Apoptose/fisiologia , Autofagia/fisiologia , Células da Medula Óssea/citologia , Diferenciação Celular/fisiologia , Linhagem Celular , Sobrevivência Celular , Técnicas de Cocultura , Feminino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Ratos , Ratos Wistar , Descolamento Retiniano/terapia , Rodopsina/biossíntese
11.
J Cell Mol Med ; 23(7): 4723-4737, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31094072

RESUMO

Retinal cell damage caused by diabetes leads to retinal microvascular injury. Roundabout 4 (ROBO4) is involved in angiogenesis, which varies with the development of diabetic retinopathy (DR). Here, we explored the transcriptional regulation and microRNA-mediated modulation of ROBO4 expression and related retinal cell function in DR. A streptozotocin-induced type I diabetic animal model was established to detect the expression of hypoxia inducible factor-1α (HIF-1α), specificity protein 1 (SP1) and ROBO4. Retinal pigment epithelium (RPE) cells were cultured under hyperglycaemia or hypoxia and used for mechanistic analysis. Furthermore, roles of miR-125b-5p and miR-146a-5p were evaluated, and their targets were identified using luciferase assays. The cell functions were evaluated by MTS assays, permeability analysis and migration assays. The development of DR increased the levels of HIF-1α, SP1 and ROBO4 both in the DR model and in hyperglycaemic/hypoxic RPE cells. They were co-expressed and up-regulated in diabetic retinas and in RPE cells under hyperglycaemia/hypoxia. Knockdown of HIF-1α significantly inhibited SP1 and ROBO4, whereas SP1 down-regulation abolished ROBO4 expression in RPE cells under hyperglycaemia/hypoxia. miR-125b-5p and miR-146a-5p were down-regulated by hyperglycaemia and/or hypoxia. Up-regulation of miRNAs reversed these changes and resulted in recovery of target gene expression. Moreover, luciferase assays confirmed miR-125b-5p targeted SP1 and ROBO4, and miR-146a-5p targeted HIF-1α and ROBO4 directly. The decreased cell viability, enhanced permeability, and increased cell migration under DR conditions were mitigated by knockdown of HIF-1α/SP1/ROBO4 or up-regulation of miR-125b-5p/miR-146a-5p. In general, our results identified a novel mechanism that miR-125b-5p/miR-146a-5p targeting HIF-1α/SP1-dependent ROBO4 expression could retard DR progression.


Assuntos
Retinopatia Diabética/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/metabolismo , Receptores de Superfície Celular/metabolismo , Fator de Transcrição Sp1/metabolismo , Regulação para Cima/genética , Animais , Sequência de Bases , Hipóxia Celular/genética , Células Cultivadas , Retinopatia Diabética/complicações , Retinopatia Diabética/patologia , Regulação para Baixo , Humanos , Hiperglicemia/complicações , Hiperglicemia/patologia , Masculino , MicroRNAs/genética , Ratos Sprague-Dawley , Retina/patologia , Transcrição Gênica
12.
Opt Express ; 27(13): 17686-17700, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31252725

RESUMO

We have focused on the optical form that is low cost while maintaining high performance for airborne application. We report the optical design as well as the alignment and test results for a push-broom imaging spectrometer. The smart architecture of the prism-grating based spectrometer ensures high uniformity and image quality. Moreover, an effective method for aligning the spectrometer is also proposed. The results of laboratory-based optical tests and a flight test confirm the easy manufacture and excellent performance. Thus, the proposed system should be suitable for use as a hyperspectral instrument that can be loaded onto airborne and unmanned aerial vehicles.

13.
Opt Express ; 25(19): 22440-22454, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-29041554

RESUMO

We discuss and evaluate a long wave infrared imaging spectrometer in terms of its opto-mechanical design and analysis, alignment, testing, and calibration. The instrument is a practical airborne sensor achieving high spectral resolution and sensitive noise equivalent delta temperature. The instrument operates in the 8 to 12.5 µm spectral region with 28.85 nm spectral sampling, 1 mrad instantaneous field of view, and >40° cross track field. The instrument comprises three uniform sub-modules with identical design parameters and performances. The sub-module design is based on a refractive foreoptics feeding an all-reflective spectrometer. The optical form of the spectrometer is a double-pass reflective triplet with a flat grating, which has a fast f/2 and high optical throughput. Cryogenic optics of 100 K is implemented only for the spectrometer. Assembly and thermal deformation and focusing adjustment design are particularly considered for this low temperature. All the mirrors of the spectrometer are opto-mechanical-integrated designed and manufactured by single-point diamond turning technology. We consider the center sub-module as an example, and we present its laboratory testing results and calibration; the results indicate the instrument's potential value in airborne sensing.

14.
J Craniofac Surg ; 28(1): 275-279, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27977487

RESUMO

PURPOSE: We performed a novel anatomical and radiological investigation to understand the structure of nasolacrimal duct (NLD) and to provide data to help surgeons locate the openings of NLD efficiently based on landmarks. MATERIALS AND METHODS: We examined the NLD region using computed tomography images of 133 individuals and 6 dry skull specimens. Multiplanar reconstruction of the computed tomography images was performed, and the anatomical features of the NLD were studied in the coronal, sagittal, and axial planes. The long and short diameters of NLD were measured along its cross-section. The position of NLD was localized using the nostril, concha nasalis media, and medial orbital corner as landmarks. The free and open source software, 3D Slicer, was used for the segmentation of the NLD and 3D visualization of the superior and inferior openings of the NLD. RESULTS: The length, angle, and diameter of NLD were significantly influenced by the age in females compared to those in males. The inferior opening of the NLD could be located efficiently using the nostril and the midsagittal line while the superior opening of NLD could be located using the medial orbital corner. Third, 3D Slicer enabled us to measure the distance between the skin and the bony structure in the image. CONCLUSION: Our study indicates that the sex and age of the patient should be considered while selecting the optimal NLD stent for a patient, and that the precise location of NLD in reference to landmarks can simplify the surgical difficulties and reduce the risk of injury during the transnasal operation.


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Ducto Nasolacrimal/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cavidade Nasal/diagnóstico por imagem , Adulto Jovem
15.
J Insect Sci ; 142014.
Artigo em Inglês | MEDLINE | ID: mdl-25525101

RESUMO

The white-backed planthopper (WBPH), Sogatella furcifera (Horváth) is a serious pest causing grievous damage to rice plants. In the present study, inter-simple sequence repeats were employed to investigate the genetic diversity of 108 samples from 27 WBPH geographic populations in China. Ten primers were screened out with 147 amplified bands, average percentage of polymorphic bands, polymorphic information content, and marker index were 78.9, 0.456, and 6.753% respectively. The results indicated that genetic diversity was different among populations, but genetic variation was as low as 0.2% among the populations and as high as 99.8% within the same geographic population. Among the examined WBPH populations, genetic distances were weakly correlated to geographic distance, and there was no correlation between genetic identity and elevation. Cluster analysis showed that the 27 WBPH populations studied could be lumped into four clusters, with which the results of principal coordinate analysis (were almost consistent. In conclusion, the molecular genetic data demonstrated that the region consisting of Yunnan, Guizhou, Guangdong, and Guangxi was the first landing area of WBPH in its migrating process from overwintering sites to China.


Assuntos
Variação Genética , Hemípteros/genética , Repetições de Microssatélites , Altitude , Migração Animal , Animais , Sequência de Bases , China , Análise por Conglomerados , DNA/genética , Geografia , Reação em Cadeia da Polimerase
16.
Int J Mol Sci ; 15(8): 14456-74, 2014 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-25141102

RESUMO

Retinitis pigmentosa (RP) is a group of inherited retinal disorders characterized by progressive loss of photoreceptors and eventually leads to retina degeneration and atrophy. Until now, the exact pathogenesis and etiology of this disease has not been clear, and many approaches for RP therapies have been carried out in animals and in clinical trials. In recent years, stem cell transplantation-based attempts made some progress, especially the transplantation of bone marrow-derived mesenchymal stem cells (BMSCs). This review will provide an overview of stem cell-based treatment of RP and its main problems, to provide evidence for the safety and feasibility for further clinical treatment.


Assuntos
Células da Medula Óssea/citologia , Células-Tronco Mesenquimais/citologia , Retinose Pigmentar/terapia , Transplante de Células-Tronco/métodos , Células da Medula Óssea/fisiologia , Humanos , Células-Tronco Mesenquimais/fisiologia
17.
Dalton Trans ; 53(12): 5665-5675, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38445301

RESUMO

The complex hydrolysis process and strong uncertainty of self-assembly rules have led to the precise synthesis of lanthanide clusters still being in the "blind-box" stage and simplifying the self-assembly process and developing reliable regulation strategies have attracted widespread attention. Herein, different anions are used to induce the construction of a series of dysprosium clusters with different shapes and connections. When the selected anion is NO3-, it blocks the coordination of metal sites around the cluster through the terminal group coordination mode, thereby controlling the growth of the cluster. When NO3- was changed to OAc-, OAc- adopted a bridging mode to induce modular units to build dysprosium clusters through an annular growth mechanism. Specifically, we selected 2-amino-6-methoxybenzoic acid, 2-hydroxybenzaldehyde, and Dy(NO3)3·6H2O to react under solvothermal conditions to obtain a pentanuclear dysprosium cluster (1). The five Dy(III) ions in 1 are distributed in upper and lower planes and are formed by the tight connection of nitrogen and oxygen atoms, and µ3-OH- bridges on the ligand. Next, octa-nuclear dysprosium cluster (2) were obtained by only regulating ligand substituents. The eight Dy(III) ions in 2 are tightly connected through ligand oxygen atoms, µ2-OH-, and µ3-OH- bridges, forming an elliptical {Dy/O} cluster core. Furthermore, only by changing NO3- to OAc-, a wheel-shaped tetradeca-nuclear dysprosium cluster (3) was obtained. Cluster 3 is composed of OAc- bridged multiple template Dy3L3 units and pulling of these template units connected by an annular growth mechanism forms a wheel-shaped cluster. The angle of the coordination site on NO3- is ∠ONO = 115°, which leads to the further extension of the metal sites on the periphery of clusters 1 and 2 through the terminal group coordination mode, thereby regulating the structural connection of the clusters. However, the angle of the coordination site on OAc- is ∠OCO = 128°, and a slightly increased angle leads to the formation of a ring-shaped cluster 3 by connecting the template units through bridging. This is a rare example of the controllable construction of lanthanide clusters with different shapes induced by the regulation of different anions, which provides a new method for the precise construction of lanthanide clusters with special shapes.

18.
J Craniofac Surg ; 24(4): 1418-22, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23851822

RESUMO

INTRODUCTION: The shape of the cavernous segment of the internal carotid artery (CSICA) is various in different people, which makes it difficult to be located and causes a higher possibility of injury in the transsphenoidal approach. Hence, a comprehensive study of the CSICA and a meaningful classification of it are rather helpful to the approach and other operations related to the CSICA. PURPOSE: Our study aimed to make a comprehensive measurement and classify the CSICA into different types so as to better describe its shape and position. MATERIALS AND METHODS: Computed tomographic angiography images of 146 internal carotid arteries in individuals (76 males and 70 females) ranging in age from 17 to 78 years (mean, 49.49 y) were reviewed. We measured the distances between the bilateral CSICA at 5 positions in the coronal plane and the angle of the posterior curve segment in the sagittal plane. According to these statistics, we divided the CSICA into different types. RESULTS: The distance between the medial walls of the bilateral internal carotid artery is similar to the previous relevant study. We classified the horizontal segment of the CSICA into 5 types: types 1, 2, 3, 4, and 5. Among the individuals we measured, the proportion of each type is 8.2%, 25.3%, 39.7%, 19.9%, and 6.9%. In addition, the posterior curve segment of the CSICA can be classified into 4 types: types Z, A, S, and O. Among the 292 sides we measured, the proportion of each type is 22.6%, 17.8%, 21.9%, and 37.7%. Furthermore, 80.8% of the people with bilateral sides of type O belonged to type 3 and 72.7% of the people with bilateral sides of type Z belonged to type 2. CONCLUSIONS: The detailed classification of the CSICA is helpful to understand its complexity. The classification of the CSICA can guide the surgeons in the transsphenoidal approach to avoid injuring and to simplify the location of the whole CSICA.


Assuntos
Artéria Carótida Interna/anatomia & histologia , Adolescente , Adulto , Idoso , Encéfalo/irrigação sanguínea , Artéria Carótida Interna/diagnóstico por imagem , Angiografia Cerebral/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Osso Esfenoide/irrigação sanguínea , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
19.
J Int Med Res ; 51(8): 3000605231193820, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37622441

RESUMO

Idiopathic hypoparathyroidism is a rare endocrine disorder characterized by hypocalcemia secondary to inadequate parathyroid hormone secretion. Hypocalcemia-related cataract is most often observed in patients with postoperative hypoparathyroidism, whereas primary hypoparathyroidism-related cataract is rare and displays slow progression. Cataract usually occurs in people aged 18 to 50 years. Here, we describe a 17-year-old boy with bilateral cataract and a history of hypocalcemic tetany who was diagnosed with idiopathic hypoparathyroidism. Phacoemulsification with implantation of a monofocal aspherical intraocular lens was performed in the right eye; 6 months later, it was performed in the left eye. Elevated phosphorus and diminished calcium were observed in blood and aqueous humor. A deep anterior chamber, relatively thin central corneal thickness, large white-to-white distance, and thin lens were also observed. During follow-up, neither eye displayed intraocular lens decentration; best-corrected visual acuity was 20/20 in both eyes. These findings suggest that ophthalmologists should be vigilant when hypocalcemic tetany and cataract are present, especially in adolescents and young adults.


Assuntos
Catarata , Hipocalcemia , Hipoparatireoidismo , Tetania , Masculino , Adulto Jovem , Humanos , Adolescente , Hipocalcemia/complicações , Hipocalcemia/diagnóstico , Catarata/complicações , Hipoparatireoidismo/complicações , Olho
20.
Biomed Pharmacother ; 149: 112814, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35290888

RESUMO

The human fungal pathogen Candida albicans can cause many kinds of infections, including biofilm infections on medical devices, while the available antifungal drugs are limited to only a few. In this study, alantolactone (Ala) demonstrated antifungal activities against C. albicans, as well as other Candida species, with a MIC of 72 µg/mL. Ala could also inhibit the adhesion, yeast-to-hyphal transition, biofilm formation and development of C. albicans. The exopolysaccharide of biofilm matrix and extracellular phospholipase production could also be reduced by Ala treatment. Ala could increase permeability of C. albicans cell membrane and ROS contribute to the anti-biofilm activity of Ala. Overall, the present study suggests that Ala may provide a promising candidate for developing antifungal drugs against C. albicans infections.


Assuntos
Candida albicans , Sesquiterpenos de Eudesmano , Antifúngicos/farmacologia , Biofilmes , Humanos , Lactonas/farmacologia , Testes de Sensibilidade Microbiana , Sesquiterpenos de Eudesmano/farmacologia
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