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1.
Appl Opt ; 63(7): 1815-1821, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437285

RESUMO

The telescope is vital for accurate gravitational wave detection in the TianQin project. It must meet criteria like a geometric tilt-to-length (TTL) coupling noise c o e f f i c i e n t≤0.02√2n m/µr a d and wavefront R M S≤λ/30. Analyzing the pupil aberration's impact on geometric TTL noise, we devised an optimization method using the chief ray spot diagram's standard deviation. Implementing this in Zemax with a ZPL macro, we designed an optical system meeting TianQin's requirements. The system has a maximum geometric TTL noise coefficient of 0.0250 nm/µrad over the science FOV and a wavefront RMS of 0.0111λ, confirming the method's feasibility.

2.
Appl Opt ; 63(6): 1488-1494, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38437360

RESUMO

The optical path length stability of the off-axis four-reflection telescope is one of the key technical indicators for the TianQin gravitational wave detection system. In the MHz observation band, the telescope must exhibit an optical path length stability of 0.4p m/H z 1/2. As a feasible solution, the optical path length stability measurement of the off-axis four-reflection telescope based on the Pound-Drever-Hall (PDH) technique imposes stringent requirements on the alignment of the off-axis resonant cavity (ORC). Taking the off-axis two-reflection prototype as the research object, we propose a Monte Carlo analysis-based method for ORC alignment precision analysis. By considering misalignment as an intermediate function, we establish a relationship between the coupling efficiency of the ORC and the wavefront aberration of the telescope. The research results show that by considering the combined effects of multiple misalignment couplings of the primary and secondary mirrors, when the detected telescope wavefront aberration is better than 0.068λ (λ=1064n m) with a probability of 98%, the ORC coupling efficiency can achieve greater than 40% with a probability of 97.13%, which can be used as the main reference indicator for system misalignment analysis. This method simplifies the alignment difficulty of the target under test and can provide alignment reference for subsequent resonant cavities with internal off-axis telescopes.

3.
Int J Mol Sci ; 24(24)2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38139397

RESUMO

Cucumber is an economically important vegetable crop, and the warts (composed of spines and Tubercules) of cucumber fruit are an important quality trait that influences its commercial value. WOX transcription factors are known to have pivotal roles in regulating various aspects of plant growth and development, but their studies in cucumber are limited. Here, genome-wide identification of cucumber WOX genes was performed using the pan-genome analysis of 12 cucumber varieties. Our findings revealed diverse CsWOX genes in different cucumber varieties, with variations observed in protein sequences and lengths, gene structure, and conserved protein domains, possibly resulting from the divergent evolution of CsWOX genes as they adapt to diverse cultivation and environmental conditions. Expression profiles of the CsWOX genes demonstrated that CsWOX9 was significantly expressed in unexpanded ovaries, especially in the epidermis. Additionally, analysis of the CsWOX9 promoter revealed two binding sites for the C2H2 zinc finger protein. We successfully executed a yeast one-hybrid assay (Y1H) and a dual-luciferase (LUC) transaction assay to demonstrate that CsWOX9 can be transcriptionally activated by the C2H2 zinc finger protein Tu, which is crucial for fruit Tubercule formation in cucumber. Overall, our results indicated that CsWOX9 is a key component of the molecular network that regulates wart formation in cucumber fruits, and provide further insight into the function of CsWOX genes in cucumber.


Assuntos
Cucumis sativus , Cucumis sativus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Regiões Promotoras Genéticas , Regulação da Expressão Gênica de Plantas , Filogenia , Frutas/metabolismo
4.
Front Pharmacol ; 13: 1027441, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339620

RESUMO

Previous studies have shown that matrine, a natural compound extracted from the herb Sophora flavescens, has a good anti-leukemia effect, but its key target and mechanism remains unclear. Here, we found that only c-Myc could respond rapidly to matrine treatment in three myeloid leukemia cell lines, and matrine inhibited both transcription and translation of c-Myc. Ribosome biogenesis and nucleotide metabolism, the key downstream of c-Myc, were significantly suppressed after matrine treatment. Therefore, our results confirmed that matrine is a special c-Myc inhibitor which suppresses ribosome biogenesis and nucleotide metabolism by inhibiting c-Myc in myeloid leukemia. This study provides scientific basis for the development of matrine derivatives to c-Myc-driven cancers.

5.
J Air Waste Manag Assoc ; 72(12): 1410-1422, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36070462

RESUMO

Aiming at the challenge of bad odors emanating from rotting perishable kitchen waste in summer within the garbage collection chain, the fan-pad system, which is widely used in agricultural facility systems, was applied to the design of community bins. In this regard, a community bin based on a fan-pad operating mechanism was developed. Computational fluid dynamics (CFD) was then used to numerically analyze the cooling effect of the community bin. Under conditions comprising of an outdoor temperature of 35 °C, an installation height of the wet curtain of the cooling system h1, an installation height of the fan h2, and varying distance d between the trash can and the wet curtain, and the average temperature T of 16 temperature measurement points was analyzed. Design-Expert software was used to design the Box-Behnken Design (BBD) experiment, and regression analysis was carried out. Under the optimized parameter combination, the average temperature T of the temperature measurement point was 24.82 °C by simulation. Through field test verification, it was established that the maximum relative error between the temperature of each measuring point and the simulation result was 1.54%, and the average temperature T fluctuated within the range of 0.5 °C of the simulation value.Implications Statement: By creatively integrating the agricultural apparatus with our daily community bin, our research presents great interdisciplinary originality and potential in wide application. Meanwhile, our research also gives a new solution to saving the energy wasted by community dust room based on air conditioner cooling. We hold the believe that our research can arrest great attention of scholars, managers, and people interested in sanitation apparatus. Additionally, our research also provides more theoretical and technical support for the design and application of sanitation collecting apparatus.


Assuntos
Temperatura Baixa , Resíduos de Alimentos , Humanos , Temperatura , Estações do Ano , Agricultura
6.
ACS Appl Mater Interfaces ; 13(43): 51736-51745, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34668690

RESUMO

Optical security involving the use of light to achieve distinctive vision effects has become a widely used approach for anticounterfeiting. Holographic multiplexing has attracted considerable interest in multiplexing security due to its high degree of freedom for manipulating the optical parameters of incident laser beams. However, the complex and time-consuming fabrication process of metasurface-based holograms and the sophisticated nature of holographic imaging systems have hindered the practical application of holographic multiplexing in anticounterfeiting. Combining holography with shape memory polymers to construct reconfigurable holograms provides a simple and efficient way for holographic multiplexing. This paper proposes a reconfigurable four-level amplitude hologram fabricated on a heat-shrinkable shape memory polymer using spatially modulated femtosecond laser pulses. Simply by triggering the shape recovery of the polymer through heating, the amplitude modulation of light by the hologram is reconfigured through the shrinking of processed microcrater pixels with three diameters, which enables variation to be achieved in reconstructed holographic images. Examples of holographic multiplexing and data encryption are used to validate the proposed method. The proposed economic and simple approach for holographic multiplexing provides an integrated and single-material solution to packaging and optical security, which has extensive potential in anticounterfeiting and optical encryption.

7.
Reprod Biol Endocrinol ; 19(1): 123, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34365964

RESUMO

BACKGROUND: Various circular RNAs (circRNAs) are dysregulated in the placenta of fetal growth restriction (FGR) fetuses, but their roles and regulatory mechanisms have not been fully elucidated. Herein, we aimed to elucidate the role of hsa_circ_0081343 in regulating the migration, invasion, and apoptosis of human extravillous trophoblast HTR-8 cells. METHODS: CircRNA and miRNA levels were examined by quantitative reverse transcription PCR (qRT-PCR). Overexpression plasmid constructs and siRNAs were used to overexpress and knockdown hsa_circ_0081343, respectively. Transwell assays and flow cytometry analyses were performed to evaluate the effects of hsa_circ_0081343 or miR-210-5p on migration, invasion, and apoptosis. Protein levels were analyzed by western blotting. Dual luciferase activity and anti-AGO2 RNA immunoprecipitation (RIP) assays were performed to identify the relationship between miR-210-5p and hsa_circ_0081343. RESULTS: Hsa_circ_0081343 expression was significantly downregulated in 37 FGR placental tissues compared to healthy placental control tissues. Hsa_circ_0081343 overexpression may inhibit apoptosis by downregulating the expression of cleaved caspase 3 and caspase 9 and alleviating the migration and invasion of HTR-8 cells by inducing the expression of MMP2 and MMP9. The dual luciferase activity and anti-AGO2 RIP assay results showed that hsa_circ_0081343 binds to miR-210-5p. miR-210-5p overexpression eliminated the effect of hsa_circ_0081343 overexpression in HTR-8 cells. Finally, DLX3 was identified as a direct target of miR-210-5p. CONCLUSIONS: hsa_circ_0081343 expression levels are significantly downregulated in FGR placental tissues. Hsa_circ_0081343 regulates the migration, invasion, and apoptosis of HTR-8 cells via the hsa-miR-210-5p/DLX3 axis.


Assuntos
Apoptose/genética , Movimento Celular/genética , Retardo do Crescimento Fetal/genética , MicroRNAs/genética , Placenta/metabolismo , RNA Circular/genética , Trofoblastos/metabolismo , Adulto , Estudos de Casos e Controles , Linhagem Celular , Feminino , Retardo do Crescimento Fetal/metabolismo , Humanos , MicroRNAs/metabolismo , Gravidez , RNA Circular/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Trofoblastos/fisiologia , Adulto Jovem
8.
Environ Sci Pollut Res Int ; 28(41): 58135-58141, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34109521

RESUMO

The extensive use of traditional cooking stoves to meet daily cooking and heating requirements has highlighted the serious problem of indoor and outdoor air pollution. This study evaluates three improved cooking and heating stoves (ICHSs) and compared them with a traditional stove as a baseline reference. The stoves' performance regarding emission and thermal efficiency was evaluated with burning raw coal. All ICHSs surpassed the baseline stove in combined heating and cooking thermal and emission performance. Among the ICHSs, Model ICHS-3 was found to have the highest average thermal efficiency, 69.6±0.8%. The lowest emission of PM2.5 was 3.2±1.6 mg/MJNET, CO 2.9±0.34 g/MJNET, and CO/CO2 2.3±0.3%, respectively. It is concluded that the use of the ICHSs should be promoted for daily cooking and heating needs. The adoption of ICHSs could contribute to significant reductions of PM2.5 and CO emissions as well as save fuel to the benefit of the household.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , China , Carvão Mineral/análise , Culinária , Calefação , Material Particulado/análise
9.
Clin Lab ; 67(4)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33865258

RESUMO

BACKGROUND: Balanced complex chromosome rearrangement (CCR) carriers are phenotypically normal but at high risk of reproductive failure, recurrent miscarriages, and affected offspring, so that cytogenetic characterizations of CCR carriers are crucial. METHODS: We report a case of CCR: 46,XX, t(6;15;10;9)(q13;q15;p11.2;q34.3) ins(9;8)(q22.33;q21.1q21.3). The peripheral blood was collected for karyotyping, single nucleotide polymorphism array (SNP-array) analysis, and whole genome mate-pair sequencing. RESULTS: The patient's karyotype is detected and identified as 46,XX, t(6;15;10;9)(q13;q15;p11.2;q34.3) ins(9;8) (q22.33;q21.1q21.3), with no significant duplication and deletion found by SNP-array analysis. There are 16 break-points among chromosomes 6, 8, 9, 10, and 15 identified by whole genome sequencing. CONCLUSIONS: With a variety of detection techniques, we can deeply study the genetic characteristics of CCRs, thus providing a basis for genetic counseling and choice of fertility.


Assuntos
Aborto Habitual , Translocação Genética , Aberrações Cromossômicas , Cromossomos , Feminino , Heterozigoto , Humanos , Cariotipagem , Gravidez
10.
Genes (Basel) ; 12(4)2021 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-33920575

RESUMO

The development of skeletal muscle is a highly ordered and complex biological process. Increasing evidence has shown that noncoding RNAs, especially long-noncoding RNAs (lncRNAs) and microRNAs, play a vital role in the development of myogenic processes. In this study, we observed that lncMyoD regulates myogenesis and changes myofiber-type composition. miR-370-3p, which is directly targeted by lncMyoD, promoted myoblast proliferation and inhibited myoblast differentiation in the C2C12 cell line, which serves as a valuable model for studying muscle development. In addition, the inhibition of miR-370-3p promoted fast-twitch fiber transition. Further analysis indicated that acyl-Coenzyme A dehydrogenase, short/branched chain (ACADSB) is a target gene of miR-370-3p, which is also involved in myoblast differentiation and fiber-type transition. Furthermore, our data suggested that miR-370-3p was sponged by lncMyoD. In contrast with miR-370-3p, lncMyoD promoted fast-twitch fiber transition. Taken together, our results suggest that miR-370-3p regulates myoblast differentiation and muscle fiber transition and is sponged by lncMyoD.


Assuntos
Acil-CoA Desidrogenases/genética , MicroRNAs/genética , Fibras Musculares de Contração Rápida/citologia , RNA Longo não Codificante/genética , Animais , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Regulação da Expressão Gênica , Camundongos , Desenvolvimento Muscular , Fibras Musculares de Contração Rápida/química
11.
Front Neurol ; 12: 622869, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679587

RESUMO

Background and Aims: YKL-40, an inflammatory biomarker, has been reported to be involved in the process and progression of atherosclerosis. Several studies have investigated the association between YKL-40 and plaque and suggested YKL-40 might be a potential biomarker for plaque instability. This study aimed to investigate the association between YKL-40 and carotid plaque instability. Methods: Based on a community-based study in Beijing from February 2014 to May 2016, 1,132 participants with carotid plaques were enrolled in this study. Data on demographics and medical history were collected through face-to-face interviews, and fasting blood samples were collected and stored. We used ultrasound to evaluate the presence of carotid plaque and its instability. The level of YKL-40 was measured by enzyme-linked immunosorbent assay (ELISA). Multivariate logistic regression analysis was performed to investigate the association between YKL-40 level and carotid atherosclerotic plaque instability. Results: The mean age of the 1,132 participants was 58.0 (52.0-64.0) years, and 560 (49.5%) were male. Unstable plaques were detected in 855 (75.53%) participants. YKL-40 level was classified into four groups according to its quartile: quartile 1: <25.47 ng/mL, quartile 2: 25.47-39.53 ng/mL, quartile 3: 39.53-70.55 ng/mL, quartile 4: ≥70.55 ng/mL. After adjusting for age, sex, smoking, alcohol drinking, medical history, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, homocysteine, high-sensitivity C-reactive protein, and plaque thickness, the top quartiles of YKL-40 level were significantly associated with unstable plaque (quartile 3: OR 2.10, 95% CI 1.29-3.40; quartile 4: OR 1.70, 95% CI 1.04-2.80). Conclusion: This study found that YKL-40 was associated with carotid plaque instability determined by ultrasound. Individuals with high YKL-40 may have a higher risk of unstable carotid plaque.

12.
J Nanosci Nanotechnol ; 21(1): 85-97, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33213615

RESUMO

Wettability is an important physical property of shale. This parameter is related to the shale material composition and the fluid properties in the shale pores and plays an important role in the exploration and development of shale oil. Wettability is affected by the scale and roughness. The contact angle at the nanoscale on a smooth surface can better reflect the wettability of shale than the contact angle at higher scales. Molecular dynamics simulations can be used to measure the contact angle on a smooth surface at the nanoscale. This paper focuses on the effects of organic matter and minerals in shale and different components of shale oil on shale wettability. Wetting models of "organic matter-oil component-water," "quartz-oil component-water" and "kaolinite-oil component-water" at the nanoscale were constructed. Molecular dynamics simulation was used to study the morphological changes of different oil components and water on different surfaces. Studies have shown that organic matter is strongly oleophilic and hydrophobic. Polar components in shale oil can make organic matter slightly hydrophilic. It was recognized by quartz wettability experiments and simulation methods at the nanoscale that the cohesive energy of a liquid has a significant influence on the degree of spreading of the liquid on the surface. The "liquid-liquid-solid" wettability experiment is an effective method for determining mineral oleophilic or hydrophilic properties. The nanoquartz in the shale is strongly hydrophilic. The water wetting angle is related to the crude oil component. Nanokaolinite can have a tetrahedral or an octahedral surface; the tetrahedral surface is oleophilic and hydrophobic, and the octahedral surface exhibits strong hydrophilicity. The wettabilities of both surfaces are related to the crude oil component.

13.
Gynecol Obstet Invest ; 86(1-2): 40-47, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33341795

RESUMO

OBJECTIVE: The aim of this study was to determine the prevalence of congenital heart defects and examine their association with preeclampsia (PE). METHODS: A clinical-based, retrospective study was conducted in Shenzhen between 2004 and 2017. Data were collected from Shenzhen Maternal and Child Health Hospital Medical Record Database. This study included all infants who were born at the hospital with or without heart defects and their mothers (N = 177,434 newborns). Data processing and analysis were performed by SPSS23.0 (Chicago, IL, USA). RESULTS: 6,852 women (3.9%) were diagnosed as PE and 1,289 newborns (7.30 per 1,000) have congenital heart disease (CHD). Prevalence of CHD in newborns of women with PE is 15.8 per 1,000 significantly higher than the overall prevalence (7.30 per 1,000). CHD in newborns has strong association with PE, especially early-onset PE (adjusted OR 3.29 and 95% CI 2.15-5.03) and severe PE (adjusted OR 2.75 and 95% CI 2.13-3.56). Among those with CHD, infants of preeclamptic women had higher prevalence of tetralogy of Fallot (43.78 vs. 28.14 per 100,000), atrial septal defect (335.67 vs. 53.93 per 100,000), ventricular dysplasia (102.16 vs. 89.69 per 100,000), and ventricular septal defect (525.39 vs. 212.22 per 100,000) than pregnant women with non-PE. CONCLUSION: PE, especially early-onset PE and severe PE, is strongly associated with offspring CHD. Our results help advance the current understanding of the association between PE and offspring CHD. So preventing PE and reducing PE may have a beneficial effect on the offspring CHD.


Assuntos
Cardiopatias Congênitas/epidemiologia , Pré-Eclâmpsia/epidemiologia , Adulto , China/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Prevalência , Estudos Retrospectivos
14.
Front Cell Dev Biol ; 8: 278, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32509771

RESUMO

BACKGROUND: Fetal growth restriction (FGR) is a worldwide problem, and a major cause of perinatal morbidity. The precise molecular mechanisms involved in placental development and function during FGR remain poorly understood. Circular RNAs (circRNAs) are important biological molecules associated with disease pathogenesis. However, the role of circRNAs in FGR has not been well studied. METHODS: circRNA expression profiles in placental tissues with and without FGR were identified by circRNA microarray. circRNA expression was verified by quantitative reverse-transcription PCR (RT-qPCR) assay. The effect of hsa_circ_0000848 and hsa-miR-6768-5p on HTR-8 cell apoptosis, migration, and invasion was evaluated. The association between hsa_circ_0000848 and hsa-miR-6768-5p was confirmed by dual luciferase activity and anti-AGO2 RNA immunoprecipitation (RIP) assays. Protein levels were examined via western blotting. RESULTS: RT-qPCR results showed that hsa_circ_0000848 expression was significantly down-regulated in FGR placenta. Hsa_circ_0000848 overexpression and hsa-miR-6768-5p inhibitor suppressed apoptosis, and promoted cell migration and invasion. In addition, hsa_circ_0000848 overexpression and hsa-miR-6768-5p inhibitor increased the protein abundance of BCL2, MMP2 and MMP9, and decreased the protein abundance of cleaved caspase-3, cleaved caspase-9, and BAX, whereas hsa_circ_0000848 knockdown caused the opposite effect. Moreover, a significant increase in hsa-miR-6768-5p expression and a negative correlation between hsa_circ_0000848 and hsa-miR-6768-5p were identified in the FGR tissues. Luciferase reporter and RIP assay results revealed binding of hsa-miR-6768-5p to hsa_circ_0000848. Furthermore, hsa-miR-6768-5p overexpression eliminated the effect of hsa_circ_0000848 overexpression in HTR-8 cells. CONCLUSIONS: hsa_circ_0000848 expression is significantly down-regulated in the FGR placenta. hsa_circ_0000848 promotes trophoblast cell migration and invasion, and inhibits cell apoptosis via the sponging of hsa-miR-6768-5p. Our study provided a novel insight into mechanisms underlying the pathogenesis of FGR, as well as into new strategies for the treatment of FGR.

15.
Microsyst Nanoeng ; 5: 48, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31645998

RESUMO

Raman spectroscopy plays a crucial role in biochemical analysis. Recently, superhydrophobic surface-enhanced Raman scattering (SERS) substrates have enhanced detection limits by concentrating target molecules into small areas. However, due to the wet transition phenomenon, further reduction of the droplet contact area is prevented, and the detection limit is restricted. This paper proposes a simple method involving femtosecond laser-induced forward transfer for preparing a hybrid superhydrophilic-superhydrophobic SERS (HS-SERS) substrate by introducing a superhydrophilic pattern to promote the target molecules to concentrate on it for ultratrace detection. Furthermore, the HS-SERS substrate is heated to promote a smaller concentrated area. The water vapor film formed by the contact of the solution with the substrate overcomes droplet collapse, and the target molecules are completely concentrated into the superhydrophilic region without loss during evaporation. Finally, the concentrated region is successfully reduced, and the detection limit is enhanced. The HS-SERS substrate achieved a final contact area of 0.013 mm2, a 12.1-fold decrease from the unheated case. The reduction of the contact area led to a detection limit concentration as low as 10-16 M for a Rhodamine 6G solution. In addition, the HS-SERS substrate accurately controlled the size of the concentrated areas through the superhydrophilic pattern, which can be attributed to the favorable repeatability of the droplet concentration results. In addition, the preparation method is flexible and has the potential for fluid mixing, fluid transport, and biochemical sensors, etc.

16.
Sci Rep ; 7(1): 2587, 2017 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-28566764

RESUMO

In this study, we evaluated the differences in hemodynamics between hemorrhagic and non-hemorrhagic moyamoya disease (MMD) and moyamoya syndrome (MMS) by measuring cerebral circulation time (CCT). This case-control study included 136 patients with MMD or MMS diagnosed between April 2015 and July 2016 at Beijing Tian Tan Hospital. Each hemisphere was analyzed separately. The difference in clinical, radiological characteristics and CCT between subtypes of MMD and MMS were analyzed statistically. The results showed that total CCT between hemorrhagic and non-hemorrhagic sides was not statistically different (16.55 s vs. 16.06 s, P = 0.562). The cerebral filling circulation time (CFCT) of hemorrhagic sides was significantly shorter than that of non-hemorrhagic sides (4.52 s vs. 5.41 s, P < 0.001), and the cerebral venous circulation time (CVCT) of hemorrhagic sides was significantly longer than that of non-hemorrhagic sides (12.02 s, vs. 10.64 s, P < 0.001). The ratio of CFCT to CVCT (F-V ratio) was inversely correlated with the possibility of hemorrhagic stroke. Therefore, we conclude that the rapid filling and poor venous drainage of cerebral circulation are likely risk factors of hemorrhagic stroke secondary to MMD or MMS. The F-V ratio can be used to identify individuals at high risk of hemorrhagic stroke.


Assuntos
Diagnóstico Diferencial , Hemorragias Intracranianas/diagnóstico , Doença de Moyamoya/diagnóstico , Adulto , Idoso , Tempo de Circulação Sanguínea/métodos , Estudos de Casos e Controles , Circulação Cerebrovascular/fisiologia , Criança , Angiografia por Tomografia Computadorizada , Feminino , Hemodinâmica/fisiologia , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/patologia , Masculino , Pessoa de Meia-Idade , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/patologia , Neuroimagem/métodos , Fatores de Risco
17.
Am J Clin Nutr ; 105(4): 810-819, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28251933

RESUMO

Background: During the past decade, an increasing number of prospective studies have focused on the association between vitamin D and cardiovascular disease (CVD). However, the evidence on the relation between serum 25-hydroxyvitamin D [25(OH)D] and the risk of overt CVD is inconclusive.Objective: We performed a dose-response meta-analysis to summarize and prospectively quantify the RR of low serum 25(OH)D concentration and total CVD (events and mortality).Design: We identified relevant studies by searching PubMed and EMBASE up to December 2015 and by hand-searching reference lists. Prospective studies based on the general population and reported RRs and 95% CIs were included. A random-effects model was used to calculate the pooled RRs. Nonlinear association was assessed by using restricted cubic spline analyses.Results: A total of 34 publications with 180,667 participants were eligible for the meta-analysis. We included 32 publications (27 independent studies) for total CVD events and 17 publications (17 independent studies) for CVD mortality. We observed an inverse association between serum 25(OH)D and total CVD events and CVD mortality, and the pooled RRs per 10-ng/mL increment were 0.90 (95% CI: 0.86, 0.94) for total CVD events and 0.88 (95% CI: 0.80, 0.96) for CVD mortality. A nonlinear association was detected for total CVD events (P-nonlinear < 0.001) and CVD mortality (P-nonlinear = 0.022).Conclusion: Serum 25(OH)D concentration was inversely associated with total CVD events and CVD mortality from the observed studies.


Assuntos
Doenças Cardiovasculares/etiologia , Deficiência de Vitamina D/complicações , Vitamina D/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/mortalidade , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Vitamina D/sangue , Deficiência de Vitamina D/sangue
18.
J Mater Chem B ; 5(4): 777-784, 2017 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32263846

RESUMO

Ultratrace molecular detections from a limited amount of highly diluted solutions can offer unprecedented benefits in the biomedical/analytical fields, such as in precancer diagnosis, forensic analysis, and food safety. However, huge difficulties exist in completely concentrating the target molecules within a sensitive area and thereby enhancing the detection sensitivity. Herein, we report the ultratrace molecular detection using a low-adhesive superhydrophobic surface-enhanced Raman spectroscopy (LAS-SERS) substrate fabricated by femtosecond laser ablation. The LAS-SERS substrate has good characteristics, including a contact angle as high as 154°, a contact angle hysteresis below 5°, and a simulated Raman signal enhancement factor of up to 6 × 106. Compared to the previously developed superhydrophobic SERS (S-SERS) methods, the low-adhesive nature of the LAS-SERS method can greatly reduce the final contact area, thus significantly enhancing the detection limit. In our experiments, the final contact area of the LAS-SERS substrate was reduced by 19.5 times, corresponding to an 88.1 times increase in the concentration effect, as compared to the highly adhesive S-SERS substrates fabricated using the same technique. The enhanced condensation effect led to a detection limit as low as 10-14 M, which shows an obvious improvement compared to that of the other non-photolithography methods. The method reported herein offers a facile and efficient approach to the cost-effective fabrication of a high-performance LAS-SERS substrate for ultratrace molecular detection.

19.
J Stroke Cerebrovasc Dis ; 25(3): 679-87, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26776436

RESUMO

BACKGROUND: Hyperhomocysteinemia, a condition that is strongly determined by dietary intake of B vitamins, has been suggested to be an independent risk factor for ischemic stroke (IS). To test this hypothesis, we performed a meta-analysis to investigate the associations between 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism, which plays a critical role in modulating plasma homocysteine concentrations, and IS risk. MATERIALS AND METHODS: We searched case-control studies on the association between MTHFR C677T genetic polymorphism and susceptibility to IS through PubMed, Embase, and Medline databases from January 2000 up to October 2014. The random-effects model was employed because moderate heterogeneity across studies was observed, as assessed by I(2) statistic. Publication bias was estimated using funnel plot and Egger's regression test. RESULTS: A total of 22 case-control studies were included in the current meta-analysis. Significant associations between MTHFR C677T genetic polymorphism and IS were found under the dominant model (pooled odds ratio [OR] = 1.40, 95% confidence interval [CI]: 1.24-1.57), the recessive model (pooled OR = 1.37, 95% CI: 1.16-1.61), and the allele model (pooled OR = 1.29, 95% CI: 1.18-1.42). CONCLUSIONS: The meta-analysis suggests that MTHFR C677T genetic polymorphism is significantly associated with susceptibility to IS, which provides evidence supporting hyperhomocysteinemia as a risk factor for stroke.


Assuntos
5,10-Metilenotetra-Hidrofolato Redutase (FADH2)/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Acidente Vascular Cerebral/genética , Isquemia Encefálica/complicações , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Bases de Dados Bibliográficas/estatística & dados numéricos , Feminino , Estudos de Associação Genética , Humanos , Masculino , Acidente Vascular Cerebral/etiologia
20.
Nanoscale ; 8(6): 3809-15, 2016 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-26815600

RESUMO

Localized surface plasmons are confined collective oscillations of electrons in metallic nanoparticles. When driven by light, the optical response is dictated by geometrical parameters and the dielectric environment and plasmons are therefore extremely important for sensing applications. Plasmons in graphene disks have the additional benefit of being highly tunable via electrical stimulation. Mechanical vibrations create structural deformations in ways where the excitation of localized surface plasmons can be strongly modulated. We show that the spectral shift in such a scenario is determined by a complex interplay between the symmetry and shape of the modal vibrations and the plasmonic mode pattern. Tuning confined modes of light in graphene via acoustic excitations, paves new avenues in shaping the sensitivity of plasmonic detectors, and in the enhancement of the interaction with optical emitters, such as molecules, for future nanophotonic devices.

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