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1.
J Nutr ; 154(7): 1994-2005, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38642744

RESUMEN

BACKGROUND: The causal nature of gut microbiota and cerebral small vessel disease (CSVD) is still obscure regardless of evidence supporting their observational correlations. OBJECTIVES: The primary objective of this research is to investigate the potentially pathogenic or protective causal impacts of specific gut microbiota on various neuroimaging subtypes of CSVD. METHODS: We obtained the latest summary-level genome-wide databases for gut microbiota and 9 CSVD traits. The univariable and multivariable Mendelian randomization (MR) studies were conducted to examine the possible causal link between exposure and outcome. Meanwhile, we conducted sensitivity analyses sequentially, containing the heterogeneity, pleiotropy, and leave-one-out analysis. Additionally, to clarify the potential bidirectional causality, the causality from CSVD traits to the identified gut microbiota was implemented through reverse MR analysis. RESULTS: The univariable MR analysis identified 22 genetically predicted bacterial abundances that were correlated with CSVD traits. Although conditioning on macronutrient dietary compositions, 2 suggestive relationships were retained using the multivariable MR analysis. Specifically, the class Negativicutes and order Selenomonadales exhibited a negative causal association with strictly lobar cerebral microbleeds, one neuroimaging trait of CSVD. There is insufficient evidence indicating the presence of heterogeneity and horizontal pleiotropy. Furthermore, the identified causal relationship was not driven by any single nucleotide polymorphism. The results of the reverse MR analysis did not reveal any statistically significant causality from CSVD traits to the identified gut microbiota. CONCLUSIONS: Our study indicated several suggestive causal effects from gut microbiota to different neuroimaging subtypes of CSVD. These findings provided a latent understanding of the pathogenesis of CSVD from the perspective of the gut-brain axis.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales , Microbioma Gastrointestinal , Análisis de la Aleatorización Mendeliana , Enfermedades de los Pequeños Vasos Cerebrales/genética , Enfermedades de los Pequeños Vasos Cerebrales/microbiología , Humanos , Estudio de Asociación del Genoma Completo
2.
BMC Neurol ; 24(1): 199, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38872077

RESUMEN

BACKGROUND: Process approach is valuable for memory assessment in Alzheimer's disease (AD) and mild cognitive impairment (MCI), yet its underlying mechanisms remain elusive. This study aims to synergize the process approach with brain structure analysis to explore both the discriminative capacity and potential mechanisms underlying the process approach. METHODS: 37 subjects of MCI, 35 subjects of AD and 38 subjects of healthy control (HC) were included. The process approach in Auditory Verbal Learning Test (AVLT), including discriminability (A'), response bias (B"D), semantic clustering (LBCsem) and serial clustering (LBCser) was performed. The gray matter volume (GMV) was analyzed by voxel-based morphometry. Receiver operating characteristic (ROC) analysis and partial correlations were conducted to explore the value of the process approach and investigate the relationship between the process approach, traditional indices of AVLT and GMV. RESULTS: ROC analysis showed the value of A', B"D and LBCser in differentiating MCI and AD. Combining AVLT-Immediately Recall (AVLT-IR) and LBCser showed a higher value in diagnosing MCI. Partial correlations revealed that in the MCI group, A' and B"D were mainly positively associated with GMV of the hippocampus and temporal lobe. CONCLUSION: This study indicated that the process approach is a promising cognitive biomarker to detect MCI and AD.


Asunto(s)
Enfermedad de Alzheimer , Biomarcadores , Disfunción Cognitiva , Sustancia Gris , Imagen por Resonancia Magnética , Humanos , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/patología , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/diagnóstico , Masculino , Femenino , Anciano , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Anciano de 80 o más Años , Pruebas Neuropsicológicas/estadística & datos numéricos
3.
Macromol Rapid Commun ; 45(7): e2300661, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38271638

RESUMEN

Photocuring 3D printing of hydrogels, with sophisticated, delicate structures and biocompatibility, attracts significant attention by researchers and possesses promising application in the fields of tissue engineering and flexible devices. After years of development, photocuring 3D printing technologies and hydrogel inks make great progress. Herein, the techniques of photocuring 3D printing of hydrogels, including direct ink writing (DIW), stereolithography (SLA), digital light processing (DLP), continuous liquid interface production (CLIP), volumetric additive manufacturing (VAM), and two photon polymerization (TPP) are reviewed. Further, the raw materials for hydrogel inks (photocurable polymers, monomers, photoinitiators, and additives) and applications in tissue engineering and flexible devices are also reviewed. At last, the current challenges and future perspectives of photocuring 3D printing of hydrogels are discussed.


Asunto(s)
Hidrogeles , Ingeniería de Tejidos , Ingeniería de Tejidos/métodos , Hidrogeles/química , Polímeros , Impresión Tridimensional , Estereolitografía
4.
J Neurosci Res ; 101(11): 1711-1727, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37469210

RESUMEN

White matter hyperintensities (WMHs) of presumed vascular origin are important imaging biomarkers of cerebral small vessel disease (CSVD). Previous studies have verified abnormal functional brain networks in CSVD. However, most of these studies rely on static functional connectivity, and only a few focus on the varying severity of the WMHs. Hence, our study primarily explored the disrupted dynamic functional network connectivity (dFNC) and topological organization variance in patients with WMHs. This study included 38 patients with moderate WMHs, 47 with severe WMHs, and 68 healthy controls (HCs). Ten independent components were chosen using independent component analysis based on resting-state functional magnetic resonance imaging. The dFNC of each participant was estimated using sliding windows and k-means clustering. We identified three reproducible dFNC states. Among them, patients with WMHs had a significantly higher occurrence in the sparsely connected State 1, but a lower occurrence and shorter duration in the positive and stronger connected State 3. Regarding topological organization variance, patients with WMHs showed higher variance in local efficiency but not global efficiency compared to HCs. Among the WMH subgroups, patients with severe WMHs showed similar but more obvious alterations than those with moderate WMHs. These altered network characteristics indicated an imbalance between the functional segregation and integration of brain networks, which was correlated with global cognition, memory, executive functions, and visuospatial abilities. Our study confirmed aberrant dFNC state metrics and topological organization variance in patients with moderate-to-severe WMHs; thus, it might provide a new pathway for exploring the pathogenesis of cognitive impairment.


Asunto(s)
Sustancia Blanca , Humanos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Imagen por Resonancia Magnética/métodos , Encéfalo/patología , Cognición , Función Ejecutiva
5.
Macromol Rapid Commun ; 44(18): e2300214, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37306260

RESUMEN

Poly(vinyl alcohol) (PVA)-based hydrogels have attracted great attention and been widely used in biological tissue engineering. With the development of modern medicine, precision medicine requires the customization of medical materials. However, lacking of photocurable functional groups or the performance of rapid phase transition makes PVA-based hydrogels difficult to be customizable molded through photocuring 3D printing technique. In this research, customizable PVA-based hydrogels with high performance through 3D photocurable printing and freezing-thawing (F-T) process are obtained. The ability of 3D-printable is endowed by the introduction of polyvinyl alcohol-styrylpyridine (PVA-SBQ), which can be photo-crosslinked quickly without photoinitiator. Meanwhile, the tunable mechanical properties are achieved by adjusting the mass ratio of PVA-SBQ to PVA, and PVA can offer the physical crosslinking points through freezing-thawing (F-T) process. The hydrogels with high resolution are prepared by digital light procession 3D printing with the mass ratio 1:1 of PVA-SBQ to PVA solution. Attributed to the absence of initiator, and no small molecule residues inside the hydrogels, the hydrogels have good biocompatibility and have the potential to be applicated in the field of biological tissue engineering.


Asunto(s)
Hidrogeles , Ingeniería de Tejidos , Hidrogeles/química , Alcohol Polivinílico/química , Materiales Biocompatibles/química
6.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(4): 571-580, 2023 Aug.
Artículo en Zh | MEDLINE | ID: mdl-37654137

RESUMEN

Objective To investigate the changes in plasma amyloid-ß (Aß) level and their relationship with white matter microstructure in the patients with amnesic mild cognitive impairment(aMCI) and vascular mild cognitive impairment (vMCI).Methods A total of 36 aMCI patients,20 vMCI patients,and 34 sex and age matched healthy controls (HC) in the outpatient and inpatient departments of the First Affiliated Hospital of Anhui Medical University were enrolled in this study.Neuropsychological scales,including the Mini-Mental State Examination,the Montreal Cognitive Assessment,and the Activity of Daily Living Scale,were employed to assess the participants.Plasma samples of all the participants were collected for the measurement of Aß42 and Aß40 levels.All the participants underwent magnetic resonance scanning to obtain diffusion tensor imaging (DTI) data.The DTI indexes of 48 white matter regions of each individual were measured (based on the ICBM-DTI-81 white-matter labels atlas developed by Johns Hopkins University),including fractional anisotropy (FA) and mean diffusivity (MD).The cognitive function,plasma Aß42,Aß40,and Aß42/40 levels,and DTI index were compared among the three groups.The correlations between the plasma Aß42/40 levels and DTI index of aMCI and vMCI patients were analyzed.Results The Mini-Mental State Examination and the Montreal Cognitive Assessment scores of aMCI and vMCI groups were lower than those of the HC group (all P<0.001).There was no significant difference in the Activity of Daily Living Scale score among the three groups (P=0.654).The plasma Aß42 level showed no significant difference among the three groups (P=0.227).The plasma Aß40 level in the vMCI group was higher than that in the HC group (P=0.014),while it showed no significant difference between aMCI and HC groups (P=1.000).The plasma Aß42/40 levels in aMCI and vMCI groups showed no significant differences from that in the HC group (P=1.000,P=0.105),while the plasma Aß42/40 level was lower in the vMCI group than in the aMCI group (P=0.016).The FA value of the left anterior limb of internal capsule in the vMCI group was lower than those in HC and aMCI groups (all P=0.001).The MD values of the left superior corona radiata,left external capsule,left cingulum (cingulate gyrus),and left superior fronto-occipital fasciculus in the vMCI group were higher than those in HC (P=0.024,P=0.001,P=0.003,P<0.001) and aMCI (P=0.015,P=0.004,P=0.019,P=0.001) groups,while the MD values of the right posterior limb of internal capsule (P=0.005,P=0.001) and left cingulum (hippocampus) (P=0.017,P=0.031) in the aMCI and vMCI groups were higher than those in the HC group.In the aMCI group,plasma Aß42/40 level was positively correlated with FA of left posterior limb of internal capsule (r=0.403,P=0.015) and negatively correlated with MD of the right fonix (r=-0.395,P=0.017).In the vMCI group,plasma Aß42/40 level was positively correlated with FA of the right superior cerebellar peduncle and the right anterior limb of internal capsule (r=0.575,P=0.008;r=0.639,P=0.002),while it was negatively correlated with MD of the right superior cerebellar peduncle and the right anterior limb of internal capsule (r=-0.558,P=0.011;r=-0.626,P=0.003).Conclusions Plasma Aß levels vary differently in the patients with aMCI and vMCI.The white matter regions of impaired microstructural integrity differ in the patients with different dementia types in the early stage.The plasma Aß levels in the patients with aMCI and vMCI are associated with the structural integrity of white matter,and there is regional specificity between them.


Asunto(s)
Disfunción Cognitiva , Sustancia Blanca , Humanos , Imagen de Difusión Tensora , Sustancia Blanca/diagnóstico por imagen , Pacientes Ambulatorios , Cognición , Péptidos beta-Amiloides
7.
J Neurovirol ; 26(6): 980-983, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32779109

RESUMEN

We report here a case of a 17-year-old boy with viral encephalitis associated with human parvovirus B19 who presented consciousness disturbance, left hemiparesis, and focal neurologic signs. The diagnosis was based on the specific sequence reads corresponding to human parvovirus B19 (PVB19) in a CSF sample as analyzed by metagenomic next-generation sequencing (mNGS). Thus, PVB19 should be considered in the differential diagnosis of encephalitis and encephalopathy of unknown etiology. The introduction of mNGS into the diagnostic protocol of neuropathies, especially for those undiagnosed, could interrogate all genetic information in a biologic sample and facilitate the identification of the etiological agent.


Asunto(s)
ADN Viral/genética , Encefalitis Viral/virología , Metagenómica/métodos , Paresia/virología , Infecciones por Parvoviridae/virología , Parvovirus B19 Humano/genética , Adolescente , Encefalitis Viral/líquido cefalorraquídeo , Encefalitis Viral/diagnóstico por imagen , Encefalitis Viral/patología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Hallazgos Incidentales , Imagen por Resonancia Magnética , Masculino , Paresia/líquido cefalorraquídeo , Paresia/diagnóstico por imagen , Paresia/patología , Infecciones por Parvoviridae/líquido cefalorraquídeo , Infecciones por Parvoviridae/diagnóstico por imagen , Infecciones por Parvoviridae/patología , Parvovirus B19 Humano/aislamiento & purificación , Parvovirus B19 Humano/patogenicidad
8.
Hum Mutat ; 40(4): 392-403, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30609140

RESUMEN

Primary familial brain calcification (PFBC) is a rare neurodegenerative disorder with four causative genes (SLC20A2, PDGFRB, PDGFB, and XPR1) that have been identified. Here, we aim to describe the mutational spectrum of four causative genes in a series of 226 unrelated Chinese PFBC patients. Mutations in four causative genes were detected in 16.8% (38/226) of PFBC patients. SLC20A2 mutations accounted for 14.2% (32/226) of all patients. Mutations in the other three genes were relatively rare, accounting for 0.9% (2/226) of all patients, respectively. Clinically, 44.8% of genetically confirmed patients (probands and relatives) were considered symptomatic. The most frequent symptoms were chronic headache, followed by movement disorders and vertigo. Moreover, the total calcification score was significantly higher in the symptomatic group compared to the asymptomatic group. Functionally, we observed impaired phosphate transport induced by seven novel missense mutations in SLC20A2 and two novel mutations in XPR1. The mutation p.D164Y in XPR1 might result in low protein expression through an enhanced proteasome pathway. In conclusion, our study further confirms that mutations in SLC20A2 are the major cause of PFBC and provides additional evidence for the crucial roles of phosphate transport impairment in the pathogenies of PFBC.


Asunto(s)
Encefalopatías/genética , Calcinosis/genética , Predisposición Genética a la Enfermedad , Mutación , Enfermedades Neurodegenerativas/genética , Adulto , Anciano , Alelos , Transporte Biológico , Biomarcadores , Encefalopatías/diagnóstico , Encefalopatías/metabolismo , Calcinosis/diagnóstico , Calcinosis/metabolismo , Línea Celular Tumoral , China , Femenino , Genes sis , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Neurodegenerativas/diagnóstico , Enfermedades Neurodegenerativas/metabolismo , Neuroimagen , Fenotipo , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Receptores Acoplados a Proteínas G/genética , Receptores Virales/genética , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo III/genética , Tomografía Computarizada por Rayos X , Receptor de Retrovirus Xenotrópico y Politrópico
9.
Bioconjug Chem ; 29(6): 2090-2099, 2018 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-29847098

RESUMEN

Microbes play an important function in our lives, while some pathogenic bacteria are responsible for many infectious diseases, food safety, and ecological pollution. Layered double hydroxide (LDH) is a kind of natural two-dimensional material and has been applied in many fields. Lysozyme is a green natural antibacterial agent, while the antimicrobial activity of lysozyme is not as good as antibiotics. We use a different ratio of cations to tune the morphology of LDH covered with lysozyme to enhance the antibacterial ability of lysozyme. We synthesize MgAl-LDH, ZnAl-LDH, and ZnMgAl-LDH covered with lysozyme, characterize the structure and morphology, test the antibacterial in culture media, and evaluate the biotoxicity in vitro and in vivo. The flower-like structure of ZnMgAl-LDH has a rough surface, covered with lysozyme with a perfect ring, and presents good antibaterial properties and promotes wound healing of mice. The bloom flower structure of ZnMgAl-LDH can enhance the loading rate of lysozyme; meanwhile, the rougher surface can adhere more bacteria, so lyso@ZnMgAl-LDH presents better antibacterial activity than the binary LDHs.


Asunto(s)
Aluminio/química , Antibacterianos/química , Hidróxidos/química , Magnesio/química , Muramidasa/química , Zinc/química , Aluminio/farmacología , Aluminio/uso terapéutico , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Escherichia coli/efectos de los fármacos , Infecciones por Escherichia coli/tratamiento farmacológico , Hidróxidos/farmacología , Hidróxidos/uso terapéutico , Magnesio/farmacología , Magnesio/uso terapéutico , Masculino , Ratones , Muramidasa/farmacología , Muramidasa/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Zinc/farmacología , Zinc/uso terapéutico
10.
Langmuir ; 34(51): 15700-15707, 2018 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-30484657

RESUMEN

The development of the oil industry brings the critical problem of ocean pollution by oil spill or fossil fuels. The use of materials for water/oil separation is one of the effective approaches to solve this crisis. Polyvinyl alcohol (PVA) has been used  to prepare water/oil separation materials. Currently, glutaraldehyde has been employed as the cross-linking agent, which is well known to be toxic and environmentally unfriendly. Moreover, it is difficult to deal with the disposal of the Across-linked material. Here, we propose a strategy of fabricating macroporous material which was prepared by PVA and sodium silicate (Na2SiO3) in aqueous solution. Following through with the one-step method of sol-gel reaction of hydroxyl groups with trimethoxy(octadecyl)silane, the low surface energy substance was grafted on the macroporous material and a super-hydrophobic macroporous membrane for water/oil separation was prepared. As oil sorbent, the as-prepared dried super-hydrophobic PVA/Na2SiO3 porous materials (PSD6S) have the adsorption capacity of 1.8-7.0 g/g for oil uptake, which depends on the type of oil liquid. Typically, the separation efficiency of this material could reach more than 99% even after 10 times of use without the help of ambient pressure. It is noteworthy that the as-prepared samples could be easily decomposable and dissolvable completely in acidic medium at a rapid rate.

11.
Macromol Rapid Commun ; 39(20): e1800144, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29806085

RESUMEN

This study reports an effective method for controlling substance-release sites of hydrogel. Glycidyl methacrylate, which contains two functional groups, namely, double-bond acrylate and epoxide, is photografted on a hydrogel surface through hydrogen abstraction photopolymerization due to the existence of a hydrogen donor, such as an amine, in the hydrogel matrix. The remaining epoxide group crosslinks the polymer chain of polyglycidyl methacrylate. Substance release of hydrogel is changed due to the altered surface texture of hydrogel. Rate and site-controlled substance release are achieved by controlling the thickness and site of surface grafting and the extent of epoxide ring opening. This study may provide a novel method for achieving hydrogel function or modified performance of other biomaterials to meet biological activity requirements.


Asunto(s)
Reactivos de Enlaces Cruzados/química , Sistemas de Liberación de Medicamentos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Polímeros/química , Materiales Biocompatibles , Reactivos de Enlaces Cruzados/síntesis química , Liberación de Fármacos , Hidrogel de Polietilenoglicol-Dimetacrilato/síntesis química , Luz , Polimerizacion/efectos de la radiación , Polímeros/síntesis química , Propiedades de Superficie
12.
Nanotechnology ; 27(21): 215301, 2016 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-27079331

RESUMEN

A magnetically separatable catalyst Fe3O4@SiO2@PEI@Au (gold) nanoparticle was successfully constructed by a novel regional selective photoreduction method. Based on the photolysis mechanism of a type II photoinitiator, through controlling the distribution of polyethylene imine (PEI), Au nanoparticles about 10 nm, which are only on the surface of the Fe3O4@SiO2@PEI nanoparticle, could be photoreduced due to the PEI acting as a coordinating agent, capping agent, and photoreducing agent simultaneously. The small size Au nanoparticles endow the catalyst with a high catalytic performance toward the reduction of 4-nitroaniline to 4-aminophenol by NaBH4. In addition, magnetic Fe3O4@SiO2@PEI@Au nanoparticles could easily be recovered and could be reused at least six times still keeping catalytic efficiency higher than 95%, which contributes to their high stability and magnetization. Furthermore, compared to another reported approach, this method showed great regional selectivity of reducing metal nanoparticles by controlling the distribution of the PEI. Taking advantage of the regional selectivity of the photoreducing method could also be used to fabricate other metal nanoparticles as catalysts for various reactions.

13.
Langmuir ; 31(3): 1210-7, 2015 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-25549246

RESUMEN

Developing a cost-effective nanolithography strategy that enables the production of subwavelength features with various shapes over large areas is a long-standing goal in the nanotechnology community. Herein, an inexpensive nanolithographic technique that combines the wafer-scale production capability of photolithography with the subwavelength feature size controllability of near-field photolithography was developed to fabricate centimeter-scale up to wafer-scale sub-100-nm variously shaped nanopatterns on surfaces. The wafer-scale elastomeric trench-based photomasks with subwavelength apertures created at the apexes were compatible with mask aligners, allowing for the production of wafer-scale subwavelength nanopatterns with adjustable feature sizes, shapes, and periodicities. The smallest feature sizes of 50 and 80 nm were achieved on positive tone and negative tone photoresist surfaces, respectively, which could be ascribed to a near-field optical effect. The fabricated centimeter-scale nanopatterns were functionalized to study cell-matrix adhesion and migration. Compared to currently developed nanolithographic methods that approach similar functionalities, this facile nanolithographic strategy combines the merits of low cost, subwavelength feature size, high throughput, and varied feature shapes, making it an affordable approach to be used in academic research for researchers at most institutions.


Asunto(s)
Técnicas Electroquímicas , Oro/química , Nanoestructuras/química , Nanotecnología/métodos , Dimetilpolisiloxanos/química , Elasticidad , Nanotecnología/instrumentación , Tamaño de la Partícula , Polimetil Metacrilato/química , Impresión/métodos
14.
Photochem Photobiol Sci ; 13(4): 651-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24519453

RESUMEN

In this paper, a new photocoinitiator for free radical photopolymerization, belonging to the benzodioxole (BDO) derivatives, was synthesized and characterized, and the effect of phenyl at the 2-position of BDO was estimated. The structure of PhBDO was characterized by elemental analysis, (1)H NMR and (13)C NMR. Laser flash photolysis (LFP) and an electron spin resonance spin trapping technique (ESR-ST) were used to study the photochemical mechanisms. The rate of decomposition (Rd) of PhBDO in acetonitrile was studied by UV-Vis spectroscopy and the photopolymerization kinetics were monitored by real time Fourier Transform near-IR (FT-IR). The FT-IR results showed that the concentration of PhBDO and BP functionalities of the acrylates and the light intensity affected the polymerization rate and the final conversion. The results showed that the BP/PhBDO system had the same hydrogen abstraction mechanism and reactivity as the BP/BDO system. Consequently, PhBDO could also be an effective coinitiator.

15.
Can J Neurol Sci ; 41(3): 375-81, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24718824

RESUMEN

OBJECTIVE: We aimed to examine changes in serum bilirubin and uric acid (ua) levels in subcortical ischemic vascular disease (Sivd). in addition, we investigated if altered serum bilirubin and ua levels correlate with the subtypes of Sivd as well as the severity of leukoaraiosis (la). METHODS: this cross-sectional study included 1098 consecutive patients with slight symptoms, such as dizziness, vertigo etc. according to magnetic resonance imaging (Mri) appearances, they were divided into either Sivd group or controls (Cn), and the Sivd group was further grouped in lacunar infarction (li) and la subtypes, as well as different grades. Serum bilirubin and ua levels were determined by the vanadate oxidase method and enzymatic method respectively, after at least an eight hour overnight fasting, in all subjects. RESULTS: the bilirubin level was obviously lower while the ua level was significantly higher in the Sivd group when compared with the controls. Moreover, the la subgroup presented more significant changes in bilirubin and ua when compared to the li subgroup in both males and females. the correlation was positive between the ua levels and the la severity (r=0.134, p=0.006). Multivariate regression analysis revealed that the odds ratio (95% Ci) for Sivd in the lowest tertile of total bilirubin (tbil<9.58 µmol/l) and highest tertile of ua (ua>339 µmol/l) were 2.702(1.936-3.770) and 2.135(1.521-2.996) respectively after adjusting for confounding variables. CONCLUSION: Serum bilirubin levels were lower, whereas ua levels were higher in Sivd patients when compared with controls in both males and females, especially in la patients. Moreover, serum ua levels positively correlated to la severity.


Asunto(s)
Antioxidantes/metabolismo , Bilirrubina/sangre , Isquemia Encefálica/sangre , Demencia Vascular/sangre , Ácido Úrico/sangre , Anciano , Biomarcadores/sangre , Isquemia Encefálica/diagnóstico , Estudios Transversales , Demencia Vascular/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
J Headache Pain ; 15: 45, 2014 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-24966056

RESUMEN

BACKGROUND: A headache circumscribed in a line-shaped area but not confined to the territory of one particular nerve had ever been described in Epicrania Fugax (EF) of which the head pain is moving and ultrashort. In a 25-month period from Feb 2012 to Mar 2014, we encountered 12 patients with a paroxysmal motionless head pain restricted in a linear trajectory. The head pain trajectory was similar to that of EF, but its all other features obviously different from those of EF. We named this distinctive but undescribed type of headache linear headache (LH). METHODS: A detailed clinical feature of the headache was obtained in all cases to differentiate with EF, trigeminal autonomic cephalalgias (TACs) and cranial neuralgia. Similarities and differences in clinical features were compared between LH and migraine. RESULTS: The twelve LH patients (mean age 43.9 ± 12.2) complained of a recurrent, moderate to severe, distending (n = 9), pressure-like (n = 3) or pulsating (n = 3) pain within a strictly unilateral line-shaped area. The painful line is distributed from occipital or occipitocervical region to the ipsilateral eye (n = 5), forehead (n = 6) or parietal region (n = 1). The pain line has a trajecory similar to that of EF but no characteristics of moving. The headache duration would be ranged from five minutes to three days, but usually from half day to one day in most cases (n = 8). Six patients had the accompaniment of nausea with or without vomiting, and two patients had the accompaniment of ipsilateral dizziness. The attacks could be either spontaneous (n = 10) or triggered by noise, depression and resting after physical activity (n = 1), or by stress and staying up late (n = 1). The frequency of attacks was variable. The patients had well response to flunarizine, sodium valproate and amitriptyline but not to carbamazepine or oxcarbazepine. LH is different from EF, trigeminal autonomic cephalalgias (TACs) and cranial neuralgia, but it had couple of features similar to that of migraine. CONCLUSIONS: The clinical picture of LH might be a subtype of migraine, or represent a novel syndrome.


Asunto(s)
Cefalea/diagnóstico , Trastornos Migrañosos/diagnóstico , Cefalalgia Autónoma del Trigémino/diagnóstico , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
17.
Artículo en Inglés | MEDLINE | ID: mdl-38593302

RESUMEN

With the fast economic development and accelerating urbanization, more and more skyscrapers made entirely of concrete and glass are being constructed. To keep a comfortable indoor environment, massive energy for air conditioning or heating appliances is consumed. A huge amount of heat (>30%) is gained or released through glass windows. Using smart windows with the capability to modulate light is an effective way to reduce building energy consumption. Thermochromic hydrogel is one of the potential smart window materials due to its excellent thermal response, high radiation-blocking efficiency, cost-effectiveness, biocompatibility, and good uniformity. In this work, polyhydroxypropyl acrylate (PHPA) hydrogels with controllable lower critical solution temperature (LCST) were prepared by photopolymerization. The transition temperature and transition rate under "static transition" conditions were investigated. Unlike "static" conditions in which the transition temperature was not affected by the initial and final temperature and heating/cooling ramp, the transition temperature varied with the rate of temperature change under dynamic conditions. The "dynamic" transition temperature of the PHPA hydrogel gradually increased with the increase of the heating rate. It was the result of the movement of the molecular chains lagging behind the temperature change when the temperature change was too fast. The results of the solar irradiation experiment by filling PHPA hydrogels into double glazing windows showed that the indoor temperature was about 15 °C lower than that of ordinary glass windows, indicating that it can significantly reduce the energy consumption of air conditioning. In addition, a wide range of adjustable transition temperatures and fast optical response make PHPA hydrogels potentially applicable to smart windows.

18.
Histol Histopathol ; : 18732, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38567631

RESUMEN

BACKGROUND: The current selection criteria of patients with stage II colorectal carcinoma (CRC) suitable for adjuvant therapy are not satisfactory. Enhancer of zeste homolog 2 (EZH2) has been demonstrated to be over-expressed in CRC. However, data regarding the role of EZH2 in CRC survival remains controversial, and little is known about it in stage II CRC. Thus, we conducted this study to investigate the clinical significance of EZH2 expression in stage II CRC. METHODS: Cases with stage II CRC resected between 2015 and 2018 were retrospectively reviewed. EZH2 expression was analyzed by immunohistochemistry using tissue microarrays. The relationship between EZH2 expression and clinicopathological variables was analyzed. Survival curves were estimated by the Kaplan-Meier approach. RESULTS: We found high EZH2 expression in 134 of 221 analyzable stage II tumors (60.63%). No significant associations were observed between EZH2 expression and common clinicopathological factors. Survival analyses showed that cases receiving surgery alone had inferior overall survival (OS) than those receiving surgery and chemotherapy (P=0.0075) in stage II CRC with high EZH2 expression, however, metastasis-free survival (MFS) was similar between these two subgroups. Treatment choice had no impact on the survival of stage II CRC with low EZH2 expression. CONCLUSION: The OS of stage II CRC with high EZH2 expression improved more strikingly with surgery and adjuvant chemotherapy than with surgery alone, which suggests the potential of EZH2 expression as a biomarker to help identify a subgroup of early-stage CRC benefiting from surgery and adjuvant chemotherapy. More large-scale studies are warranted to corroborate this finding and to further evaluate the predictive nature of EZH2.

19.
Chem Commun (Camb) ; 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39196312

RESUMEN

Diblock copolymers of phenyl methacrylate (PMA) and butyl methacrylate (BMA) were synthesized using dual-wavelength photopolymerization with a bifunctional photoinitiator 2-(4-(2-hydroxy-2-methylpropanoyl)phenoxy)ethyl(E)-3-(1-methyl-1H-pyrrol-2-yl)acrylate (PAA-2959).

20.
ACS Appl Mater Interfaces ; 16(23): 29600-29609, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38832656

RESUMEN

Hydrogel tubes made of sodium alginate (SA) have potential applications in drug delivery, soft robots, biomimetic blood vessels, tissue stents, and other fields. However, the continuous preparation of hollow SA hydrogel tubes with good stability and size control remains a huge challenge for chemists, material scientists, and medical practitioners. Inspired by the plant apical growth strategy, a new method named soft cap-guided growth was proposed to produce SA hydrogel tubes. Due to the introduction of inert low gravity substances, such as air and heptane, into the extrusion needle in front of calcium chloride solution to form a soft cap, the SA hydrogel tubes with controllable sizes were fabricated rapidly and continuously without using a template through a negative gravitropism mechanism. The SA hydrogel tubes had good tensile strength, high burst pressure, and good cell compatibility. In addition, hydrogel tubes with complex patterns were conveniently created by controlling the motion path of a soft cap, such as a rotating SA bath or magnetic force. Our research provided a simple innovative technique to steer the growth of hydrogel tubes, which made it possible to mass produce hydrogel tubes with controllable sizes and programmable patterns.


Asunto(s)
Alginatos , Hidrogeles , Alginatos/química , Hidrogeles/química , Resistencia a la Tracción
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