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1.
Proc Natl Acad Sci U S A ; 120(4): e2213441120, 2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36649431

RESUMEN

A twin boundary (TB) is a common low energy planar defect in crystals including those with the atomic diamond structure (C, Si, Ge, etc.). We study twins in a self-assembled soft matter block copolymer (BCP) supramolecular crystal having the double diamond (DD) structure, consisting of two translationally shifted, interpenetrating diamond networks of the minority polydimethyl siloxane block embedded in a polystyrene block matrix. The coherent, low energy, mirror-symmetric double tubular network twin has one minority block network with its nodes offset from the (222) TB plane, while nodes of the second network lie in the plane of the boundary. The offset network, although at a scale about a factor of 103 larger, has precisely the same geometry and symmetry as a (111) twin in atomic single diamond where the tetrahedral units spanning the TB retain nearly the same strut (bond) lengths and strut (bond) angles as in the normal unit cell. In DD, the second network undergoes a dramatic restructuring-the tetrahedral nodes transform into two new types of mirror-symmetric nodes (pentahedral and trihedral) which alternate and link to form a hexagonal mesh in the plane of the TB. The collective reorganization of the supramolecular packing highlights the hierarchical structure of ordered BCP phases and emphasizes the remarkable malleability of soft matter.


Asunto(s)
Vendajes , Diamante , Grupos Minoritarios , Polímeros , Poliestirenos
2.
Nature ; 575(7781): 175-179, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31659340

RESUMEN

Supramolecular soft crystals are periodic structures that are formed by the hierarchical assembly of complex constituents, and occur in a broad variety of 'soft-matter' systems1. Such soft crystals exhibit many of the basic features (such as three-dimensional lattices and space groups) and properties (such as band structure and wave propagation) of their 'hard-matter' atomic solid counterparts, owing to the generic symmetry-based principles that underlie both2,3. 'Mesoatomic' building blocks of soft-matter crystals consist of groups of molecules, whose sub-unit-cell configurations couple strongly to supra-unit-scale symmetry. As yet, high-fidelity experimental techniques for characterizing the detailed local structure of soft matter and, in particular, for quantifying the effects of multiscale reconfigurability are quite limited. Here, by applying slice-and-view microscopy to reconstruct the micrometre-scale domain morphology of a solution-cast block copolymer double gyroid over large specimen volumes, we unambiguously characterize its supra-unit and sub-unit cell morphology. Our multiscale analysis reveals a qualitative and underappreciated distinction between this double-gyroid soft crystal and hard crystals in terms of their structural relaxations in response to forces-namely a non-affine mode of sub-unit-cell symmetry breaking that is coherently maintained over large multicell dimensions. Subject to inevitable stresses during crystal growth, the relatively soft strut lengths and diameters of the double-gyroid network can easily accommodate deformation, while the angular geometry is stiff, maintaining local correlations even under strong symmetry-breaking distortions. These features contrast sharply with the rigid lengths and bendable angles of hard crystals.

3.
Phys Rev Lett ; 132(21): 218201, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38856277

RESUMEN

Amphiphiles self-assemble into a variety of bicontinuous mesophases whose equilibrium structures take the form of high-symmetry cubic networks. Here, we show that the symmetry-breaking distortions in these systems give rise to anomalously large, nonaffine collective deformations, which we argue to be a generic consequence of "mass equilibration" within deformed networks. We propose and study a minimal "liquid network" model of bicontinuous networks, in which acubic distortions are modeled by the relaxation of residually stressed mechanical networks with constant-tension bonds. We show that nonaffinity is strongly dependent on the valency of the network as well as the degree of strain-softening or strain-stiffening tension in the bonds. Taking diblock copolymer melts as a model system, liquid network theory captures quantitative features of two bicontinuous phases based on comparison with self-consistent field theory predictions and direct experimental characterization of acubic distortions, which are likely to be pronounced in soft amphiphilic systems more generally.

4.
Anim Genet ; 55(2): 265-276, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38185881

RESUMEN

In livestock, genome-wide association studies (GWAS) are usually conducted in a single population (single-GWAS) with limited sample size and detection power. To enhance the detection power of GWAS, meta-analysis of GWAS (meta-GWAS) and mega-analysis of GWAS (mega-GWAS) have been proposed to integrate data from multiple populations at the level of summary statistics or individual data, respectively. However, there is a lack of comparison for these different strategies, which makes it difficult to guide the best practice of GWAS integrating data from multiple study populations. To maximize the comparison of different association analysis strategies across multiple populations, we conducted single-GWAS, meta-GWAS, and mega-GWAS for the backfat thickness of 100 kg (BFT_100) and days to 100 kg (DAYS_100) within each of the three commercial pig breeds (Duroc, Yorkshire, and Landrace). Based on controlling the genome inflation factor to one, we calculated corrected p-values (pC ). In Yorkshire, with the largest sample size, mega-GWAS, meta-GWAS and single-GWAS detected 149, 38 and 20 significant SNPs (pC < 1E-5) associated with BFT_100, as well as 26, four, and one QTL, respectively. Among them, pC of SNPs from mega-GWAS was the lowest, followed by meta-GWAS and single-GWAS. The correlation of pC among the three GWAS strategies ranged from 0.60 to 0.75 and the correlation of SNP effect values between meta-GWAS and mega-GWAS was 0.74, all showing good agreement. Collectively, even though there are differences in the integration of individual data or summary statistics, integrating data from multiple populations is an effective means of genetic argument for complex traits, especially mega-GWAS versus single-GWAS.


Asunto(s)
Estudio de Asociación del Genoma Completo , Sitios de Carácter Cuantitativo , Porcinos , Animales , Polimorfismo de Nucleótido Simple , Herencia Multifactorial , Fenotipo
5.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33723049

RESUMEN

Periodic gyroid network materials have many interesting properties (band gaps, topologically protected modes, superior charge and mass transport, and outstanding mechanical properties) due to the space-group symmetries and their multichannel triply continuous morphology. The three-dimensional structure of a twin boundary in a self-assembled polystyrene-b-polydimethylsiloxane (PS-PDMS) double-gyroid (DG) forming diblock copolymer is directly visualized using dual-beam scanning microscopy. The reconstruction clearly shows that the intermaterial dividing surface (IMDS) is smooth and continuous across the boundary plane as the pairs of chiral PDMS networks suddenly change their handedness. The boundary plane therefore acts as a topological mirror. The morphology of the normally chiral nodes and strut loops within the networks is altered in the twin-boundary plane with the formation of three new types of achiral nodes and the appearance of two new classes of achiral loops. The boundary region shares a very similar surface/volume ratio and distribution of the mean and Gaussian curvatures of the IMDS as the adjacent ordered DG grain regions, suggesting the twin is a low-energy boundary.

6.
Nano Lett ; 23(16): 7743-7749, 2023 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-37406355

RESUMEN

Photodynamic molecular beacons (PMBs) are highly appealing for activatable photodynamic therapy (PDT), but their applications are hindered by limited therapeutic efficacy. Here, by molecular engineering of enzyme-responsive units in the loop region of DNA-based PMBs, we present for the first time the modular design of an enzyme/microRNA dual-regulated PMB (D-PMB) to achieve cancer-cell-selective amplification of PDT efficacy. In the design, the "inert" photosensitizers in D-PMB could be repeatedly activated in the presence of both tumor-specific enzyme and miRNA, leading to amplified generation of cytotoxic singlet oxygen species and therefore enhanced PDT efficacy in vitro and in vivo. By contrast, low photodynamic activity could be observed in healthy cells, as D-PMB activation has been largely avoided by the dual-regulatable design. This work presents a cooperatively activated PDT strategy, which enables enhanced therapeutic efficacy with improved tumor-specificity and thus conceptualizes an approach to expand the repertoire of designing smart tumor treatment modality.


Asunto(s)
MicroARNs , Neoplasias , Fotoquimioterapia , Humanos , MicroARNs/genética , MicroARNs/uso terapéutico , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Oxígeno Singlete , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/patología , Línea Celular Tumoral
7.
Int J Mol Sci ; 25(11)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38891877

RESUMEN

The domestic pig (Sus scrofa) and its subfamilies have experienced long-term and extensive gene flow, particularly in Southeast Asia. Here, we analyzed 236 pigs, focusing on Yunnan indigenous, European commercial, East Asian, and Southeast Asian breeds, using the Pig Genomics Reference Panel (PGRP v1) of Pig Genotype-Tissue Expression (PigGTEx) to investigate gene flow and associated complex traits by integrating multiple database resources. In this study, we discovered evidence of admixtures from European pigs into the genome of Yunnan indigenous pigs. Additionally, we hypothesized that a potential conceptual gene flow route that may have contributed to the genetic composition of the Diannan small-ear pig is a gene exchange from the Vietnamese pig. Based on the most stringent gene introgression scan using the fd statistic, we identified three specific loci on chromosome 8, ranging from 51.65 to 52.45 Mb, which exhibited strong signatures of selection and harbored the NAF1, NPY1R, and NPY5R genes. These genes are associated with complex traits, such as fat mass, immunity, and litter weight, in pigs, as supported by multiple bio-functionalization databases. We utilized multiple databases to explore the potential dynamics of genetic exchange in Southeast Asian pig populations and elucidated specific gene functionalities.


Asunto(s)
Flujo Génico , Animales , Asia Sudoriental , Porcinos/genética , Bases de Datos Genéticas , Sus scrofa/genética , Genética de Población , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Genotipo , Cruzamiento , Pueblos del Sudeste Asiático
8.
BMC Genomics ; 24(1): 743, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38053015

RESUMEN

BACKGROUND: Chinese indigenous pigs in Yunnan exhibit considerable phenotypic diversity, but their population structure and the biological interpretation of signatures of artificial selection require further investigation. To uncover population genetic diversity, migration events, and artificial selection signatures in Chinese domestic pigs, we sampled 111 Yunnan pigs from four breeds in Yunnan which is considered to be one of the centres of livestock domestication in China, and genotyped them using Illumina Porcine SNP60K BeadChip. We then leveraged multiple bioinformatics database tools to further investigate the signatures and associated complex traits. RESULTS: Population structure and migration analyses showed that Diannanxiaoer pigs had different genetic backgrounds from other Yunnan pigs, and Gaoligongshan may undergone the migration events from Baoshan and Saba pigs. Intriguingly, we identified a possible common target of sharing artificial selection on a 265.09 kb region on chromosome 5 in Yunnan indigenous pigs, and the genes on this region were associated with cardiovascular and immune systems. We also detected several candidate genes correlated with dietary adaptation, body size (e.g., PASCIN1, GRM4, ITPR2), and reproductive performance. In addition, the breed-sharing gene MMP16 was identified to be a human-mediated gene. Multiple lines of evidence at the mammalian genome, transcriptome, and phenome levels further supported the evidence for the causality between MMP16 variants and the metabolic diseases, brain development, and cartilage tissues in Chinese pigs. Our results suggested that the suppression of MMP16 would directly lead to inactivity and insensitivity of neuronal activity and skeletal development in Chinese indigenous pigs. CONCLUSION: In this study, the population genetic analyses and identification of artificial selection signatures of Yunnan indigenous pigs help to build an understanding of the effect of human-mediated selection mechanisms on phenotypic traits in Chinese indigenous pigs. Further studies are needed to fully characterize the process of human-mediated genes and biological mechanisms.


Asunto(s)
Metaloproteinasa 16 de la Matriz , Sus scrofa , Humanos , Porcinos/genética , Animales , Metaloproteinasa 16 de la Matriz/genética , China , Sus scrofa/genética , Genoma , Biología Computacional , Selección Genética , Polimorfismo de Nucleótido Simple
9.
J Transl Med ; 21(1): 790, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37936118

RESUMEN

BACKGROUND: Although chronic inflammation, oxidative stress, airway remodeling, and protease-antiprotease imbalance have been implicated in chronic obstructive pulmonary disease (COPD), the exact pathogenesis is still obscure. Gene transcription and post-transcriptional regulation have been taken into account as key regulators of COPD occurrence and development. Identifying the hub genes and constructing biological regulatory networks at the post-transcriptional level will help extend current knowledge on COPD pathogenesis and develop potential drugs. METHODS: All lung tissues from non-smokers (n = 6), smokers without COPD (smokers, n = 7), and smokers with COPD (COPD, n = 7) were collected to detect messenger RNA (mRNA), microRNA (miRNA), circular RNA (circRNA), and long non-coding RNA (lncRNA) expression and identify the hub genes. Biological regulatory networks were constructed at the post-transcriptional level, including the RNA-binding protein (RBP)-hub gene interaction network and the competitive endogenous RNA (ceRNA) network. In addition, we assessed the composition and abundance of immune cells in COPD lung tissue and predicted potential therapeutic drugs for COPD. Finally, the hub genes were confirmed at both the RNA and protein levels. RESULTS: Among the 20 participants, a total of 121169 mRNA transcripts, 1871 miRNA transcripts, 4244 circRNA transcripts, and 122130 lncRNA transcripts were detected. There were differences in the expression of 1561 mRNAs, 48 miRNAs, 33 circRNAs, and 545 lncRNAs between smokers and non-smokers, as well as 1289 mRNAs, 69 miRNAs, 32 circRNAs, and 433 lncRNAs between smokers and COPD patients. 18 hub genes were identified in COPD. TGF-ß signaling and Wnt/ß-catenin signaling may be involved in the development of COPD. Furthermore, the circRNA/lncRNA-miRNA-mRNA ceRNA networks and the RBP-hub gene interaction network were also constructed. Analysis of the immune cell infiltration level revealed that M2 macrophages and activated NK cells were increased in COPD lung tissues. Finally, we identified that the ITK inhibitor and oxybutynin chloride may be effective in treating COPD. CONCLUSIONS: We identified several novel hub genes involved in COPD pathogenesis. TGF-ß signaling and Wnt/ß-catenin signaling were the most dysregulated pathways in COPD patients. Our study constructed post-transcriptional biological regulatory networks and predicted small-molecule drugs for the treatment of COPD, which enhanced the existing understanding of COPD pathogenesis and suggested an innovative direction for the therapeutic intervention of the disease.


Asunto(s)
MicroARNs , Enfermedad Pulmonar Obstructiva Crónica , ARN Largo no Codificante , Humanos , ARN Circular/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , beta Catenina , MicroARNs/genética , MicroARNs/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Redes Reguladoras de Genes , Enfermedad Pulmonar Obstructiva Crónica/genética , Factor de Crecimiento Transformador beta
10.
Cardiovasc Diabetol ; 22(1): 225, 2023 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-37633905

RESUMEN

BACKGROUND: Estimated glucose disposal rate (eGDR), a simple and noninvasive measure of insulin resistance, has been proven to be an independent risk factor for first-time stroke and all-cause mortality. In this study, we aimed to investigate the associations between eGDR and the stroke outcome in patients with first-time acute ischemic stroke (AIS). METHODS: We included first-time AIS patients with available data on eGDR in the China National Stroke Registry III (CNSR-III), and divided the subjects into lower eGDR group (eGDR ≤ 6 mg/kg/min) and higher eGDR group (eGDR > 6 mg/kg/min). The primary outcome was excellent functional outcome (modified Rankin Scale score 0-1) at 3 months. Secondary outcomes included stroke recurrence and favorable functional outcome (modified Rankin Scale score 0-2) at 3 months, and functional outcome and combined vascular event at one year. Univariate and multivariate analyses were performed to evaluate the association between eGDR and outcomes. RESULTS: A total of 6,271 patients with AIS were included in this study. The median values of eGDR in lower and higher eGDR group were 5.0 mg/kg/min (interquartile range, 4.2-5.6) and 7.6 mg/kg/min (interquartile range, 6.8-9.6), respectively. Patients with higher eGDR were significantly associated with higher incidence of excellent functional outcome (adjusted odds ratio, 1.24; 95% confidence interval, 1.06-1.45; P < 0.01) at 3 months and favorable (adjusted odds ratio, 1.55; 95% confidence interval, 1.24-1.93; P < 0.01) and excellent (adjusted odds ratio, 1.28; 95% confidence interval, 1.08-1.51; P < 0.01) functional outcome at one year. However, there was no significant difference in stroke recurrence between these two groups at 3 months (adjusted odds ratio, 0.81; 95% confidence interval, 0.61-1.06; P = 0.12) and one year (adjusted odds ratio, 0.91; 95% confidence interval, 0.73-1.14; P = 0.41). CONCLUSION: eGDR is a predictor of functional outcome in patients with AIS, independent of traditional cardiovascular predictors.


Asunto(s)
Resistencia a la Insulina , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular Isquémico/diagnóstico , Accidente Cerebrovascular Isquémico/terapia , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , China/epidemiología , Glucosa
11.
Anim Genet ; 54(2): 113-122, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36461674

RESUMEN

Breed identification utilizing multiple information sources and methods is widely applicated in the field of animal genetics and breeding. Simultaneously, with the development of artificial intelligence, the integration of high-throughput genomic data and machine learning techniques is increasingly used for breed identification. In this context, we used 654 individuals from 15 pig breeds, evaluating the performance of machine learning and stacking ensemble learning classifiers, as well as the function of feature selection and anomaly detection in different scenarios. Our results showed that, when using a training set of 16 individuals per breed and 32 features (SNPs), the accuracy of breed identification with feature selection (eXtreme Gradient Boosting, XGBoost) could exceed 95.00% (nine breeds), and was improved by 7.04% over the results with random selection. For stacking ensemble learning, feature selection methods (including random selection method) were used before different base learners. When these base learners' training set had 16 individuals per breed and 32 features, the accuracy of stacking ensemble learning improved by 9.24% over the best base learner (nine breeds), but did not significantly increase the advantage over the models with XGBoost feature selection. When using a training set of 16 individuals and 512 features per breed, breed identification with anomaly detection (local outlier factor, LOF) and random selection could achieve an accuracy of 89.06% (15 breeds). These results show that machine learning could be an effective tool for breed identification and this study will also provide useful information for the application of machine learning in animal genetics and breeding.


Asunto(s)
Inteligencia Artificial , Polimorfismo de Nucleótido Simple , Animales , Porcinos , Algoritmos , Aprendizaje Automático , Genómica
12.
BMC Neurol ; 22(1): 349, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36109692

RESUMEN

OBJECTIVE: We aimed to investigate whether negative diffusion weighted imaging (DWI) is related to the in-hospital clinical outcomes for ischemic stroke patients with intravenous tissues plasminogen activator (IV tPA). METHODS: We retrospectively enrolled patients who received IV tPA therapy within 4.5 hours from symptoms onset. The classification of DWI-positive or negative was based on post-IV tPA MR scan. Demographic factors, stroke characteristics, imaging information, and the in-hospital clinical outcomes including early neurological improvement (ENI) and favourable functional outcome were collected. Multivariable logistic regression and sensitivity analyses were conducted to test whether negative DWI imaging was an independent predictor of the in-hospital clinical outcomes. RESULTS: In the final study population, 437 patients treated with IV tPA were included and 12.36% of them had negative DWI imaging at the first MR scan post IV tPA. In the DWI-negative group, 51.9% (28/54) of the patients achieved ENI at 24 hours and 74.1% (40/54) of the patients achieved favourable clinical outcome at discharge. DWI-negative was not related to ENI (adjusted odds ratio 0.93, 95% confidence interval 0.17-4.91) or favourable clinical outcome (adjusted odds ratio 2.40, 95% confidence interval 0.48-11.95). Additional sensitivity analyses yielded similar results. CONCLUSION: DWI-negative is not associated with ENI or favourable functional outcome at discharge.


Asunto(s)
Fibrinolíticos , Accidente Cerebrovascular , Fibrinolíticos/efectos adversos , Hospitales , Humanos , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica/efectos adversos , Resultado del Tratamiento
13.
J Am Chem Soc ; 143(33): 12935-12942, 2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34387467

RESUMEN

We report the preparation of hexagonal mesoporous silica from single-source giant surfactants constructed via dihydroxyl-functionlized polyhedral oligomeric silsesquioxane (DPOSS) heads and a polystyrene (PS) tail. After thermal annealing, the obtained well-ordered hexagonal hybrid was pyrolyzed to afford well-ordered mesoporous silica. A high porosity (e.g., 581 m2/g) and a uniform and narrow pore size distribution (e.g., 3.3 nm) were achieved. Mesoporous silica in diverse shapes and morphologies were achieved by processing the precursor. When the PS tail length was increased, the pore size expanded accordingly. Moreover, such pyrolyzed, ordered mesoporous silica can help to increase both efficiency and stability of nanocatalysts.

14.
Respir Res ; 22(1): 192, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34210319

RESUMEN

BACKGROUND: To explore the role of family with sequence similarity 13 member A (FAM13A) in TGF-ß1-induced EMT in the small airway epithelium of patients with chronic obstructive pulmonary disease (COPD). METHODS: Small airway wall thickness and protein levels of airway remodeling markers, EMT markers, TGF-ß1, and FAM13A were measured in lung tissue samples from COPD and non-COPD patients. The correlations of FAM13A expression with COPD severity and EMT marker expression were evaluated. Gain- and loss-of-function assays were performed to explore the functions of FAM13A in cell proliferation, motility, and TGF-ß1-induced EMT marker alterations in human bronchial epithelial cell line BEAS-2B. RESULTS: Independent of smoking status, lung tissue samples from COPD patients exhibited significantly increased small airway thickness and collagen fiber deposition, along with enhanced protein levels of remodeling markers (collagen I, fibronectin, and MMP-9), mesenchymal markers (α-SMA, vimentin, and N-cadherin), TGF-ß1, and FAM13A, compared with those from non-COPD patients. FAM13A expression negatively correlated with FEV1% and PO2 in COPD patients. In small airway epithelium, FAM13A expression negatively correlated with E-cadherin protein levels and positively correlated with vimentin protein levels. In BEAS-2B cells, TGF-ß1 dose-dependently upregulated FAM13A protein levels. FAM13A overexpression significantly promoted cell proliferation and motility in BEAS-2B cells, whereas FAM13A silencing showed contrasting results. Furthermore, FAM13A knockdown partially reversed TGF-ß1-induced EMT marker protein alterations in BEAS-2B cells. CONCLUSIONS: FAM13A upregulation is associated with TGF-ß1-induced EMT in the small airway epithelium of COPD patients independent of smoking status, serving as a potential therapeutic target for anti-EMT therapy in COPD.


Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias)/fisiología , Transición Epitelial-Mesenquimal/fisiología , Proteínas Activadoras de GTPasa/biosíntesis , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Mucosa Respiratoria/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Adulto , Anciano , Remodelación de las Vías Aéreas (Respiratorias)/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Células Cultivadas , Transición Epitelial-Mesenquimal/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/patología , Mucosa Respiratoria/efectos de los fármacos , Mucosa Respiratoria/patología
15.
Artículo en Inglés | MEDLINE | ID: mdl-33785575

RESUMEN

BACKGROUND: Intracranial arterial stenosis (ICAS) is an important cause of stroke worldwide. Separate reports in Caucasians and Asians with stroke/transient ischaemic attack (TIA) have suggested lower ICAS prevalence in Caucasians, but there has been no direct comparisons of the two ethnic groups with the same criteria to define ICAS. METHODS: Acute minor stroke or TIA patients in two cohorts respectively recruiting patients in Oxford (2011-2018, predominantly Caucasians) and Hong Kong (2011-2015, predominantly Chinese) were compared. ICAS was defined as ≥50% stenosis/occlusion in any major intracranial artery in MR/CT angiography. Prevalence, distribution and risk factors of ICAS were compared between the two cohorts. We also systematically reviewed literature on ICAS prevalence in stroke/TIA patients in different populations. RESULTS: Among 1287 patients from Oxford and 691 from Hong Kong (mean age 69 vs 66), ICAS prevalence was higher in Chinese than in Caucasians (43.0% vs 20.0%; OR 3.02; 95% CI 2.47 to 3.70; p<0.001), independent of age (age-adjusted OR 3.73; 95% CI 3.00 to 4.63; p<0.001) and vascular risk factors (multivariable-adjusted OR 3.21; 95% CI 2.56 to 4.02; p<0.001). This ethnic difference was greater (p interaction=0.005) at age <70 years (OR 5.33; 95% CI 3.79 to 7.50; p<0.001) than at ≥70 years (OR 2.81; 95% CI 2.11 to 3.74; p<0.001). ICAS prevalence increased with age and with vascular risk factors in both cohorts, with equivalent prevalence in Chinese aged <60 years and Caucasians aged ≥80, and in Chinese with no vascular risk factor and Caucasians with two vascular risk factors. ICAS locations also differed between Chinese and Caucasian patients. CONCLUSIONS: Chinese are more susceptible to ICAS than Caucasians, with an earlier onset age and a higher prevalence, independent of vascular risk factors.

16.
Ophthalmic Res ; 64(3): 356-362, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32966980

RESUMEN

OBJECTIVES: To evaluate dry eye (DE) and associated meibomian gland dysfunction parameters after Implantable Collamer Lens (ICL) surgery. METHODS: This is a prospective observational case series. Patients who underwent ICL implantation without previous ocular diseases or ophthalmic treatments were enrolled. Their Ocular Surface Disease Index (OSDI), noninvasive breakup time (NIBUT), meibography, slit-lamp examination of the lid margin, corneal fluorescein staining (CFS), and Schirmer test I were examined preoperatively and at 1 and 3 months postoperatively. RESULTS: A total of 117 eyes of 60 patients were enrolled, and 107 eyes completed 3-month follow-up period. OSDI, lid marginal abnormality, and meibomian gland (MG) secretion, and meibum quality score were significantly higher at 1 month postoperatively and recovered partially at 3 months after surgeries, while NIBUT was significantly decreased all the time. Patients with previous DE symptoms (OSDI score ≥12) showed not only lower Schirmer and TBUT values but also higher CFS, lid margin score, MG loss, MG secretion, and meibum quality scores compared with those in the control group after operations. Low Schirmer, NIBUT values, and high meibum quality score were determined as risk factors for DE symptoms after ICL surgery. CONCLUSIONS: ICL implantation has a bad influence on the ocular surface and MG functions. The influence may be more obvious in patients with existing DE.


Asunto(s)
Síndromes de Ojo Seco , Lentes Intraoculares , Síndromes de Ojo Seco/diagnóstico , Síndromes de Ojo Seco/etiología , Fluoresceína , Humanos , Glándulas Tarsales/diagnóstico por imagen , Estudios Prospectivos , Lágrimas
17.
Stroke ; 51(6): 1862-1864, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32312220

RESUMEN

Background and Purpose- There is debate over an optimal systolic blood pressure (SBP) in secondary stroke prevention of patients with symptomatic intracranial atherosclerotic stenosis (sICAS). We investigated whether translesional pressure gradient across sICAS would alter the relationship between SBP and risk of recurrent stroke in such patients. Methods- We recruited patients with sICAS (50%-99% stenosis) confirmed in computed tomography angiography. We simulated blood flow across sICAS with computed tomography angiography-based computational fluid dynamics models. Translesional pressure ratio (PR=Pressurepost-stenotic/Pressurepre-stenotic) was calculated in each case. Pressure ratio (PR) ≤ median was defined as low PR, indicating larger translesional pressure gradient across sICAS. All patients received optimal medical treatment. We investigated the interaction of translesional PR and mean SBP during follow-up (SBPFU) in determining the risk of the primary outcome, recurrent ischemic stroke in the same territory within 1 year. Results- Among 157 patients with sICAS, the median PR was 0.93. Multivariate Cox regression revealed significant PR-SBPFU interaction on the primary outcome (P=0.008): in patients with normal PR, risk of primary outcome significantly decreased with lower SBPFU (hazard ratio for 10 mm Hg decrement =0.46; P=0.018); however, in those with low PR, SBPFU≤130 mm Hg was associated with significantly increased risk of primary outcome, compared with 130

Asunto(s)
Presión Sanguínea , Isquemia Encefálica , Angiografía Cerebral , Angiografía por Tomografía Computarizada , Arteriosclerosis Intracraneal , Modelos Cardiovasculares , Accidente Cerebrovascular , Anciano , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/fisiopatología , Constricción Patológica/diagnóstico por imagen , Constricción Patológica/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Arteriosclerosis Intracraneal/diagnóstico por imagen , Arteriosclerosis Intracraneal/fisiopatología , Masculino , Persona de Mediana Edad , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/fisiopatología
18.
Ann Neurol ; 85(5): 752-764, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30840312

RESUMEN

OBJECTIVE: To investigate whether hemodynamic features of symptomatic intracranial atherosclerotic stenosis (sICAS) might correlate with the risk of stroke relapse, using a computational fluid dynamics (CFD) model. METHODS: In a cohort study, we recruited patients with acute ischemic stroke attributed to 50 to 99% ICAS confirmed by computed tomographic angiography (CTA). With CTA-based CFD models, translesional pressure ratio (PR = pressurepoststenotic /pressureprestenotic ) and translesional wall shear stress ratio (WSSR = WSSstenotic - throat /WSSprestenotic ) were obtained in each sICAS lesion. Translesional PR ≤ median was defined as low PR and WSSR ≥4th quartile as high WSSR. All patients received standard medical treatment. The primary outcome was recurrent ischemic stroke in the same territory (SIT) within 1 year. RESULTS: Overall, 245 patients (median age = 61 years, 63.7% males) were analyzed. Median translesional PR was 0.94 (interquartile range [IQR] = 0.87-0.97); median translesional WSSR was 13.3 (IQR = 7.0-26.7). SIT occurred in 20 (8.2%) patients, mostly with multiple infarcts in the border zone and/or cortical regions. In multivariate Cox regression, low PR (adjusted hazard ratio [HR] = 3.16, p = 0.026) and high WSSR (adjusted HR = 3.05, p = 0.014) were independently associated with SIT. Patients with both low PR and high WSSR had significantly higher risk of SIT than those with normal PR and WSSR (risk = 17.5% vs 3.0%, adjusted HR = 7.52, p = 0.004). INTERPRETATION: This work represents a step forward in utilizing computational flow simulation techniques in studying intracranial atherosclerotic disease. It reveals a hemodynamic pattern of sICAS that is more prone to stroke relapse, and supports hypoperfusion and artery-to-artery embolism as common mechanisms of ischemic stroke in such patients. Ann Neurol 2019;85:752-764.


Asunto(s)
Isquemia Encefálica/diagnóstico por imagen , Hemodinámica/fisiología , Arteriosclerosis Intracraneal/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Anciano , Isquemia Encefálica/epidemiología , Isquemia Encefálica/fisiopatología , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Arteriosclerosis Intracraneal/epidemiología , Arteriosclerosis Intracraneal/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/fisiopatología
19.
Chemistry ; 26(30): 6741-6756, 2020 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-31961977

RESUMEN

Hierarchical structures are important for transferring and amplifying molecular functions to macroscopic properties of materials. In this regard, rodlike molecules have emerged as one of the most promising molecular building blocks to construct functional materials. Although the self-assembly of conventional molecules containing rodlike components generally results in nematic or layered smectic phases, due to the preferred parallel arrangements of rodlike components, extensive efforts have revealed that rational molecular design provides a versatile platform to engineer rich self-assembled structures. Herein, first successes achieved in polyphilic liquid crystals and rod-coil block systems are summarized. Special attention is paid to recent progress in the conjugation of rodlike building blocks with other molecular building blocks through the molecular Lego approach. Rod-based giant surfactants, sphere-rod conjugates, and dendritic rodlike molecules are covered. Future perspectives of the self-assembly of molecules containing rodlike components are also provided.

20.
Macromol Rapid Commun ; 41(1): e1900534, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31747084

RESUMEN

Microscopic structures have a significant influence on the properties of ceramics. The development of macromolecular self-assembly has allowed for control over microscopic structures of ceramics to prepare ceramics with diverse compositions and ordered nanostructures. Herein, recent progress in the preparation of ceramics with periodically ordered nanostructures guided by phase-separated macromolecules are reviewed, which can be summarized as a general strategy termed the "macromolecule-guided strategy." Moreover, two different subcategories, namely, the macromolecule-templated method and the macromolecule-precursor method, are illustrated. In the former method, amphiphilic macromolecules are used as templates to guide the assembly of inorganic species into ordered nanostructures, which are subsequently converted into ceramics; in the latter method, amphiphilic macromolecules containing non-volatile elements are used as the single-source precursors for ordered ceramics. It is believed that the unique diversity and tunable features of macromolecular self-assembly might offer unprecedented opportunities in the development of functional ceramics for various applications.


Asunto(s)
Cerámica/química , Sustancias Macromoleculares/química , Nanoestructuras/química , Geles/química , Metales/química , Óxidos/química , Polímeros/química , Porosidad , Silicio/química
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