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1.
Stat Med ; 43(14): 2713-2733, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38690642

RESUMO

This article presents a novel method for learning time-varying dynamic Bayesian networks. The proposed method breaks down the dynamic Bayesian network learning problem into a sequence of regression inference problems and tackles each problem using the Markov neighborhood regression technique. Notably, the method demonstrates scalability concerning data dimensionality, accommodates time-varying network structure, and naturally handles multi-subject data. The proposed method exhibits consistency and offers superior performance compared to existing methods in terms of estimation accuracy and computational efficiency, as supported by extensive numerical experiments. To showcase its effectiveness, we apply the proposed method to an fMRI study investigating the effective connectivity among various regions of interest (ROIs) during an emotion-processing task. Our findings reveal the pivotal role of the subcortical-cerebellum in emotion processing.


Assuntos
Teorema de Bayes , Emoções , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Emoções/fisiologia , Cadeias de Markov , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Simulação por Computador
2.
J Neurosci ; 44(25)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38658167

RESUMO

Alzheimer's disease (AD) is a devastating neurodegenerative disease that affects millions of seniors in the United States. Resting-state functional magnetic resonance imaging (rs-fMRI) is widely used to study neurophysiology in AD and its prodromal condition, mild cognitive impairment (MCI). The intrinsic neural timescale (INT), which can be estimated through the magnitude of the autocorrelation of neural signals from rs-fMRI, is thought to quantify the duration that neural information is stored in a local circuit. Such heterogeneity of the timescales forms a basis of the brain functional hierarchy and captures an aspect of circuit dynamics relevant to excitation/inhibition balance, which is broadly relevant for cognitive functions. Given that, we applied rs-fMRI to test whether distinct changes of INT at different hierarchies are present in people with MCI, those progressing to AD (called Converter), and AD patients of both sexes. Linear mixed-effect model was implemented to detect altered hierarchical gradients across populations followed by pairwise comparisons to identify regional differences. High similarities between AD and Converter were observed. Specifically, the inferior temporal, caudate, and pallidum areas exhibit significant alterations in both AD and Converter. Distinct INT-related pathological changes in MCI and AD were found. For AD/Converter, neural information is stored for a longer time in lower hierarchical areas, while higher levels of hierarchy seem to be preferentially impaired in MCI leading to a less pronounced hierarchical gradient. These results inform that the INT holds great potential as an additional measure for AD prediction, even a stable biomarker for clinical diagnosis.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Imageamento por Ressonância Magnética , Humanos , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/diagnóstico por imagem , Masculino , Feminino , Idoso , Imageamento por Ressonância Magnética/métodos , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Progressão da Doença , Mapeamento Encefálico/métodos
3.
Artigo em Chinês | MEDLINE | ID: mdl-38563179

RESUMO

Objective:To analyze and summarize the clinical characteristics, diagnosis, treatment and prognosis of benign upper airway space occupancy in infants. Methods:The clinical data of 141 cases with begin upper airway space from January 2012 to January 2022 were analyzed. Among them, 101 were male and 68 were female, the age is 0-3 years old. In which there were 24 newborns. The clinical characteristics, auxiliary examination and treatment results were summarized and analyzed. Results:The main clinical manifestations of 141 infants were dyspnea and/or laryngeal wheezing, including 116 cases of congenital cyst of tongue, 15 cases of hair polyps, 4 cases of nasopharyngeal second pharyngeal fissure cysts, 2 cases of congenital laryngeal cysts, 2 cases of pharyngeal bronchial cyst, 1 case of nasopharyngeal teratoma and 1 case of myofibroma. All the infants had completed the corresponding examination and treatment. The diagnosis was clear, and there was no missed diagnosis or misdiagnosis. Among them, 19 infants with congenital cyst of tongue were given cyst puncture to relieve dyspnea. 2 cases of congenital cyst of tongue recurred half a year after operaion, and then they underwent reoperation. The prognosis of the remaining infants were good. Conclusion:The most common occupying of benign upper airway space occupancy is cyst, and low-temperature plasma resection under endoscope is the main treatment method. Timely puncture therapy is also a safe and effective treatment for infants who are dyspnea and life threatening.


Assuntos
Cistos , Laringe , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Cistos/cirurgia , Dispneia , Nasofaringe , Recidiva Local de Neoplasia
4.
Ecology ; 105(6): e4300, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38650396

RESUMO

Ongoing habitat loss and fragmentation caused by human activities represent one of the greatest causes of biodiversity loss. However, the effects of habitat loss and fragmentation are not felt equally among species. Here, we examined how habitat loss influenced the diversity and abundance of species from different trophic levels, with different traits, by taking advantage of an inadvertent experiment that created habitat islands from a once continuous forest via the creation of the Thousand Island Lake, a large reservoir in China. On 28 of these islands with more than a 9000-fold difference in their area (0.12-1154 ha), we sampled plants, herbivorous insects, and predatory insects using effort-controlled sampling and analyses. This allowed us to discern whether any observed differences in species diversity were due to passive sampling alone or to demographic effects that disproportionately influenced some species relative to others. We found that while most metrics of sampling effort-controlled diversity increased with island area, the strength of the effect was exacerbated for species in higher trophic levels. When we more explicitly examined differences in species composition among islands, we found that the pairwise difference in species composition among islands was dominated by species turnover but that nestedness increased with differences in island area, indicating that some species are more likely to be absent from smaller islands. Furthermore, by examining trends of several dispersal-related traits of species, we found that species with lower dispersal propensity tended to be those that were lost from smaller islands, which was observed for herbivorous and predatory insects. Our results emphasize the importance of incorporating within-patch demographic effects, as well as the taxa and traits of species when understanding the influence of habitat loss on biodiversity.


Assuntos
Biodiversidade , Ecossistema , Insetos , Ilhas , Animais , Insetos/fisiologia , China , Plantas/classificação , Cadeia Alimentar , Distribuição Animal , Conservação dos Recursos Naturais
5.
Biomed Mater ; 19(3)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38430567

RESUMO

In our previous study, the pristine bilayer small-diameterin situtissue engineered vascular grafts (pTEVGs) were electrospun from a heparinized polycaprolactone (PCL45k) as an inner layer and a non-heparinized PCL80k as an outer layer in the thickness of about 131 µm and 202 µm, respectively. However, the hydrophilic enhancement of inner layer stemmed from the heparinization accelerated the degradation of grafts leading to the early formation of arterial aneurysms in a period of 3 months, severely hindering the perennial observation of the neo-tissue regeneration, host cell infiltration and graft remodeling in those implanted pTEVGs. Herein to address this drawback, the thickness of the outer layers was increased with PCL80k to around 268 µm, while the inner layer remained unchangeable. The thickened TEVGs named as tTEVGs were evaluated in six rabbits via a carotid artery interpositional model for a period of 9 months. All the animals kept alive and the grafts remained patent until explantation except for one whose one side of arterial blood vessels was occluded after an aneurysm occurred at 6 months. Although a significant degradation was observed in the implanted grafts at 9 month, the occurrence of aneurysms was obviously delayed compared to pTEVGs. The tissue stainings indicated that the endothelial cell remodeling was substantially completed by 3 months, while the regeneration of elastin and collagen remained smaller and unevenly distributed in comparison to autologous vessels. Additionally, the proliferation of macrophages and smooth muscle cells reached the maximum by 3 months. These tTEVGs possessing a heparinized inner layer and a thickened outer layer exhibited good patency and significantly delayed onset time of aneurysms.


Assuntos
Aneurisma , Poliésteres , Engenharia Tecidual , Animais , Coelhos , Prótese Vascular , Artérias Carótidas
6.
ArXiv ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38313195

RESUMO

Functional connectivity (FC) as derived from fMRI has emerged as a pivotal tool in elucidating the intricacies of various psychiatric disorders and delineating the neural pathways that underpin cognitive and behavioral dynamics inherent to the human brain. While Graph Neural Networks (GNNs) offer a structured approach to represent neuroimaging data, they are limited by their need for a predefined graph structure to depict associations between brain regions, a detail not solely provided by FCs. To bridge this gap, we introduce the Gated Graph Transformer (GGT) framework, designed to predict cognitive metrics based on FCs. Empirical validation on the Philadelphia Neurodevelopmental Cohort (PNC) underscores the superior predictive prowess of our model, further accentuating its potential in identifying pivotal neural connectivities that correlate with human cognitive processes.

7.
ACS Appl Mater Interfaces ; 16(1): 957-965, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38151466

RESUMO

Developing novel porous adsorbents for efficient wastewater treatment is significant to the environment protection. Herein, three porous polycalix[n]arenes (n = 4, 6, and 8) which had varying cavity sizes of the macrocycle (Azo-CX4P, Azo-CX6P, and Azo-CX8P) were prepared under mild conditions and tested for their potential application in water purification. Azo-CX8P with a larger cavity size of the macrocycle outperformed Azo-CX4P and Azo-CX6P in screening studies involving a range of organic micropollutants. It was proved that Azo-CX8P was especially efficient in the removal of cationic dyes because of its high negative surface charge. In terms of the adsorption of Rhodamine B with Azo-CX8P, the pseudo-second-order rate constant reaches 5.025 g·mg-1·min-1 with the maximum adsorption capacity being 1345 mg·g-1. These values are significantly higher compared with those recorded for most adsorbents. In addition, the easily prepared Azo-CX8P can be reused at least six times without a loss of the adsorption efficiency, demonstrating its potential use in water purification.

8.
bioRxiv ; 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37808862

RESUMO

Alzheimer's disease (AD) is a devastating neurodegenerative disease that affects millions of older adults in the US and worldwide. Resting-state functional magnetic resonance imaging (rs-fMRI) has become a widely used neuroimaging tool to study neurophysiology in AD and its prodromal condition, mild cognitive impairment (MCI). The intrinsic neural timescale (INT), which can be estimated through the magnitude of the autocorrelation of intrinsic neural signals using rs-fMRI, is thought to quantify the duration that neural information is stored in a local cortical circuit. The heterogeneity of the timescales is considered to be a basis of the functional hierarchy in the brain. In addition, INT captures an aspect of circuit dynamics relevant to excitation/inhibition (E/I) balance, which is thought to be broadly relevant for cognitive functions. Here we examined its relevance to AD. We used rs-fMRI data of 904 individuals from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. The subjects were divided into 4 groups based on their baseline and end-visit clinical status, which were cognitively normal (CN), stable MCI, Converter, and AD groups. Linear mixed effect model and pairwise comparison were implemented to investigate the large-scale hierarchical organization and local differences. We observed high similarities between AD and Converter groups. Specifically, among the eight identified ROIs with distinct INT alterations in AD, three ROIs (inferior temporal, caudate, pallidum areas) exhibit stable and significant alteration in AD converter. In addition, distinct INT related pathological changes in stable MCI and AD/Converter were found. For AD and Converter groups, neural information is stored for a longer time in lower hierarchical order areas, while higher levels of hierarchy seem to be preferentially impaired in stable MCI leading to a less pronounced hierarchical gradient effect. These results inform that the INT holds great potential as an additional measure for AD prediction, a stable biomarker for clinical diagnosis and an important therapeutic target in AD.

9.
Nat Genet ; 55(7): 1232-1242, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37291196

RESUMO

Setaria italica (foxtail millet), a founder crop of East Asian agriculture, is a model plant for C4 photosynthesis and developing approaches to adaptive breeding across multiple climates. Here we established the Setaria pan-genome by assembling 110 representative genomes from a worldwide collection. The pan-genome is composed of 73,528 gene families, of which 23.8%, 42.9%, 29.4% and 3.9% are core, soft core, dispensable and private genes, respectively; 202,884 nonredundant structural variants were also detected. The characterization of pan-genomic variants suggests their importance during foxtail millet domestication and improvement, as exemplified by the identification of the yield gene SiGW3, where a 366-bp presence/absence promoter variant accompanies gene expression variation. We developed a graph-based genome and performed large-scale genetic studies for 68 traits across 13 environments, identifying potential genes for millet improvement at different geographic sites. These can be used in marker-assisted breeding, genomic selection and genome editing to accelerate crop improvement under different climatic conditions.


Assuntos
Setaria (Planta) , Mapeamento Cromossômico , Setaria (Planta)/genética , Setaria (Planta)/metabolismo , Melhoramento Vegetal , Fenótipo , Locos de Características Quantitativas , Genoma de Planta/genética , Filogenia , Proteínas de Plantas/genética
10.
Front Plant Sci ; 14: 1214980, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37360722

RESUMO

Over the past fifty years, the distribution patterns of C4 species, across large spatial scales, are largely ignored. Here, we endeavored to examine patterns in the taxonomic and phylogenetic diversity of species with C4 photosynthetic pathways across the broad spatial extent of China and relate those to climatic gradients. We built a database of all plants with the C4 photosynthetic pathway in China. We analyzed the geographic distributions, taxonomic diversity, phylogenetic diversity, and phylogenetic structure of all C4 species, as well as the three families with the most C4 species (Poaceae, Amaranthaceae and Cyperaceae), and compared their values along temperature and precipitation gradients at two scales-the level of the province and at the 100 x 100 km grid cell. We found 644 C4 plants (belonging to 23 families 165 genera) in China, with Poaceae (57%), Amaranthaceae (17%), Cyperaceae (13%) accounting for the majority of species. Standardized effect size values of phylogenetic distances were negative overall, indicating that C4 species showed a phylogenetic clustering pattern. Southern China had the highest species richness and the highest degree of phylogenetic clustering. C4 tended to be more phylogenetically over-dispersed in regions with colder and/or drier climates, but more clustered in warmer and/or wetter climates. Patterns within individual families were more nuanced. The distribution of C4 species and its phylogenetic structure across China was constrained by temperature and precipitation. C4 species showed a phylogenetic clustering pattern across China, while different families showed more nuanced responses to climate variation, suggesting a role for evolutionary history.

11.
Artigo em Chinês | MEDLINE | ID: mdl-36987954

RESUMO

Objective:To explore the relationship between sleep status and the disease in children with recurrent vertigo(RVC) by analyzing the objective sleep condition of children with recurrent vertigo. Methods:According to the diagnostic criteria of RVC, 50 children with RVC and 20 normal controls without RVC were selected. According to the vertigo questionnaire score, the RVC group was divided into mild, moderate and severe groups according to severity. Continuous polysomnography(PSG) was performed for all participants, and SPSS 25.0 statistical software was used to analyze the monitoring results. Results:①There were significant differences in sleep time of each period, total sleep time and sleep efficiency between RVC group and control group(P<0.05), but there was no significant difference in sleep latency(P>0.05). The specific manifestations were that the proportion of sleep time in N1 and N2 phases increased, the proportion of sleep time in N3 and REM phases decreased, the total sleep time and sleep efficiency decreased in RVC group. ②The abnormal rate of sleep apnea hypopnea index, that is, the proportion of AHI≥5 times/h and the abnormal rate of lowest blood oxygen saturation in RVC group were higher than those in normal control group. There was significant difference between the two groups(P<0.05). ③There were significant differences in the proportion of AHI≥5 times/h and lowest SpO2 among mild group, moderate group and severe group(P<0.05). ④There was no significant correlation between the degree of vertigo and the abnormal rate of AHI in children with RVC, but there was a negative correlation between the degree of vertigo and the abnormal rate of lowest SpO2 in children with RVC. Conclusion:Children with RVC are often accompanied by sleep disorders, clinicians should pay attention to both the symptoms of vertigo and sleep condition in children. Polysomnography is non-invasive and operable, providing a new idea to the auxiliary examination of RVC in children. It is of certain clinical significance for the comprehensive treatment of children with RVC to actively improve vertigo symptoms and pay attention to improving sleep quality.


Assuntos
Apneia Obstrutiva do Sono , Humanos , Criança , Polissonografia , Apneia Obstrutiva do Sono/diagnóstico , Sono , Tontura , Vertigem/diagnóstico
12.
Biomater Adv ; 142: 213138, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36219919

RESUMO

Tissue engineering is thought to the most promising strategy to develop successful small diameter vascular grafts (SDVG) to meet clinical demand. The introduction of natural substances into the SDVG made from synthetic biomaterials can improve the biocompatibility to promote the regeneration of SDVG in vivo. Due to that natural materials from different sources may have property deviation, it is vital to determine the source of natural materials to optimize SDVG fabrication for tissue engineering applications. In this study, bioactive SDVGs were prepared via coating of heparin-modified poly-(ε-caprolactone) scaffolds with a precursor solution containing vascular extracellular matrix (VECM) components and subsequent in situ gelation. The mechanical properties, degradation behaviors, and morphologies of the SDVGs were thoroughly characterized and evaluated. Cell experiments demonstrated the in vitro tissue specificity of the VECM that could promote the proliferation of endothelial cells better than skin-derived collagen. Furthermore, three types of SDVGs, SDVGs with blank hydrogel, SDVGs with skin-derived collagen, and SDVGs with vascular extracellular matrix (VECM-SDVGs), were implanted into the abdominal aorta of rats for one month. The explanted SDVGs were then comprehensively evaluated using hematoxylin and eosin, Masson, von Kossa staining, and immunohistochemical staining for CD31, α-SMA, and MHC. The results showed that the VECM-SDVGs showed the best endothelium regeneration, appropriate intima regeneration, and no calcification, indicating the in vivo specificity of the fabricated VECM-SDVGs. Thus, long-term implantation of VECM-SDVGs was performed. The results showed that a complete endothelial layer formed after 6 months of implantation, and the amount of contractile SMCs in the regenerative smooth muscle layer approached the amount of native aorta at the 12th month. Consequently, relying on vascular tissue specificity, VECM-SDVGs can modulate the regenerative behavior of the implanted SDVGs in vivo to achieve satisfactory vascular regeneration both in short- and long-term implantation.


Assuntos
Hidrogéis , Engenharia Tecidual , Ratos , Animais , Engenharia Tecidual/métodos , Células Endoteliais , Poliésteres/química , Matriz Extracelular , Colágeno
13.
BMC Pediatr ; 22(1): 553, 2022 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-36123658

RESUMO

BACKGROUND: Bacterial infection of adenoid is currently considered to be an important cause of adenoid hypertrophy (AH) in children. Although several bacteriology studies on adenoid diseases have been reported, the aerobic bacterial study regarding risk factors and antibiotic sensitivity of AH in Chinese children is lacking. This study aims to investigate the risk factors for aerobic bacterial colonization of AH in Chinese children and to elucidate aerobic bacterial profiles and antibiotic sensitivity. METHODS: Samples were collected from the adenoid core and surface tissue of 466 children undergoing adenoidectomy. Aerobic cultures and antibiotic sensitivity were observed. The risk factors for bacterial colonization of adenoid were analyzed statistically. RESULTS: A total of 143 children could be detected opportunistic pathogens in adenoid surface and/or core tissue, with a carriage rate of 30.7%. The presence of chronic rhinosinusitis, tonsillar hypertrophy and adenoidal size were the risk factors for aerobic bacterial colonization of adenoid in univariate analysis. Multivariate analysis showed that chronic rhinosinusitis and tonsil hypertrophy were significant variables associated with the aerobic bacterial colonization. The most frequently isolated aerobic bacteria were Haemophilus influenzae, followed by Staphylococcus aureus and Streptococcus pneumoniae. There was no statistically significant difference in bacterial species between the adenoid surface and core. The above common bacteria were more sensitive to cephalosporins and quinolones antibiotics, and significantly resistant to penicillin antibiotics and non-ß-lactamase inhibitors. CONCLUSION: Our results provide recent aerobic bacterial profiles for AH among Chinese children and confirm the risk factors and antibiotic sensitivity. This study contributes to understanding the role of different risk factors in the development of AH and will be helpful to the treatment of AH among Chinese children.


Assuntos
Tonsila Faríngea , Quinolonas , Infecções Estafilocócicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias Aeróbias , Cefalosporinas , Criança , China , Humanos , Hipertrofia , Penicilinas , Fatores de Risco
14.
Molecules ; 27(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36080317

RESUMO

Considering the metal-based nanocrystal (NC) hierarchical structure requirements in many real applications, starting from basic synthesis principles of electrostatic spinning technology, the formation of functionalized fibrous materials with inorganic metallic and semiconductor nanocrystalline materials by electrostatic spinning synthesis technology in recent years was reviewed. Several typical electrostatic spinning synthesis methods for nanocrystalline materials in polymers are presented. Finally, the specific applications and perspectives of such electrostatic spun nanofibers in the biomedical field are reviewed in terms of antimicrobial fibers, biosensing and so on.


Assuntos
Nanopartículas Metálicas , Nanofibras , Nanofibras/química , Polímeros/química , Eletricidade Estática
15.
Neuroimage ; 260: 119451, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35842099

RESUMO

Functional connectivity (FC) between brain region has been widely studied and linked with cognition and behavior of an individual. FC is usually defined as the correlation or partial correlation of fMRI blood oxygen level-dependent (BOLD) signals between two brain regions. Although FC has been effective to understand brain organization, it cannot reveal the direction of interactions. Many directed acyclic graph (DAG) based methods have been applied to study the directed interactions but their performance was limited by the small sample size while high dimensionality of the available data. By enforcing group regularization and utilizing samples from both case and control groups, we propose a joint DAG model to estimate the directed FC. We first demonstrate that the proposed model is efficient and accurate through a series of simulation studies. We then apply it to the case-control study of schizophrenia (SZ) with data collected from the MIND Clinical Imaging Consortium (MCIC). We have successfully identified decreased functional integration, disrupted hub structures and characteristic edges (CtEs) in SZ patients. Those findings have been confirmed by previous studies with some identified to be potential markers for SZ patients. A comparison of the results between the directed FC and undirected FC showed substantial differences in the selected features. In addition, we used the identified features based on directed FC for the classification of SZ patients and achieved better accuracy than using undirected FC or raw features, demonstrating the advantage of using directed FC for brain network analysis.


Assuntos
Esquizofrenia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Estudos de Casos e Controles , Humanos , Imageamento por Ressonância Magnética/métodos , Esquizofrenia/diagnóstico por imagem
16.
Biomater Sci ; 10(15): 4257-4270, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35766246

RESUMO

As thermoplastic polyurethane (TPU) elastomers possess good biocompatibility and mechanical properties similar to those of native vascular tissues, they were intended to be co-electrospun with poly(ε-caprolactone) (PCL) onto the outer surface of PCL electrospun small-diameter single-layer vascular grafts (SLVGs) in this study, combining with surface heparinization. In this work, a kind of structurally reinforced TPU+PCL/PCL small-diameter bilayer vascular graft (BLVG) was fabricated via layer-by-layer electrospinning followed by the heparinization of PCL via EDC/NHS chemistry. The resulting (TPU+PCL/PCL)-Hep BLVGs presented excellent mechanical strength and higher compliance, and sustainably released heparin exhibited enhanced anti-coagulation activity. During 6-month implantation in 18 rat abdominal aortas, these vascular prostheses induced the remodeling and regeneration of neovascular tissues, and promoted ECM deposition. Compared to heparinized PCL (PCL-Hep) SLVGs, the formation of aneurysm was completely inhibited and the onset of calcification was significantly delayed in (TPU+PCL/PCL)-Hep BLVGs. Not only vascular cell makers co-expressed by CD206+ cells were identified, but also a high content of elastin was evidenced due to the improvement of mechanical strength and compliance. These results indicated the feasibility and efficacy of inhibiting the aneurysm formation and boosting the vascular remodeling by incorporating TPU into PCL-Hep small-diameter artificial vascular grafts.


Assuntos
Prótese Vascular , Poliuretanos , Animais , Aorta Abdominal/cirurgia , Poliésteres/química , Poliuretanos/química , Ratos , Alicerces Teciduais/química
17.
Biomater Adv ; 133: 112628, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35527159

RESUMO

Increasingly growing problems in vascular access for long-term hemodialysis lead to a considerable demand for synthetic small diameter vascular prostheses, which usually suffer from some drawbacks and are associated to high failure rates. Incorporating the concept of in situ tissue engineering (TE) into synthetic small diameter blood vessels, for example, thermoplastic poly(ether urethane) (TPU) ones, could provide an alternative approach for vascular access that profits from the advantages of excellent mechanical properties of synthetic polymer materials (early cannulation) and unique biointegration regeneration of autologous neovascular tissues (long-term fistulae). In this study, a kind of heparinized small diameter (d = 2.5 mm) TPU/poly(ε-caprolactone) (TPU/PCL-Hep) bi-layered blood vessels was electrospun with an inner layer of PCL and an outer layer of TPU. Afterward, the inner surface heparinization was conducted by coupling H2N-PEG-NH2 to the corroded PCL layer and then heparin to the attached H2N-PEG-NH2 via the EDCI/NHS chemistry. Herein a heparinized PCL inner layer could not only inhibit thrombosis, but also provide sufficient space for the neotissue regeneration via biodegradation with time. Meanwhile, a TPU outer layer could confer the vascular access the good mechanical properties, such as flexibility, viability and fitness of elasticity between the grafts and host blood vessels as evidenced by the adequate mechanical properties, such as compliance (4.43 ± 0.07%/ 100 mmHg), burst pressure (1447 ± 127 mmHg) and suture retention strength (1.26 ± 0.07 N) without blood seepage after implantation. Furthermore, a rabbit carotid aortic replacement model for 5 months was demonstrated 100% animal survival and 86% graft patency. Puncture assay also revealed the puncture resistance and self-sealing (hemostatic time < 2 min). Histological analysis highlighted neotissue regeneration, host cell infiltration and graft remodeling in terms of extracellular matrix turnover. Altogether, these results showed promising aspects of small diameter TPU/PCL-Hep bi-layered grafts for hemodialytic vascular access applications.


Assuntos
Substitutos Sanguíneos , Alicerces Teciduais , Animais , Artérias Carótidas/cirurgia , Poliésteres/química , Coelhos , Engenharia Tecidual/métodos , Alicerces Teciduais/química
18.
J Neurosci Methods ; 372: 109539, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35219769

RESUMO

BACKGROUND: Functional connectomes have been proven to be able to predict an individual's traits, acting as a fingerprint. A majority of studies use the amplitude information of fMRI signals to construct the connectivity but it remains unknown whether phase synchronization can be incorporated for improved prediction of individual cognitive behaviors. METHODS: In this paper, we address the issue by extracting phase information from the fMRI time series with a phase locking approach, followed by the construction of functional connectomes. RESULTS: We first examine the identification and prediction performance using phase-based profiles in comparison with amplitude-based connectomes. We then combine both phase-based and amplitude-based connectivity to extract subject-specific information enabled by the phase synchronization. Results show that high individual identification rates (from 82.7% to 92.6%) can be achieved by phase-based connectomes. Phase-based connectivity offers unique information complementary to amplitude-based signals. Intra-network phase-locking appears more informative for individual prediction. In addition, phase synchronization can be used to predict cognitive behaviors. COMPARISON WITH EXISTING METHOD: The amplitude-based connectivity cannot capture the subject-specific information due to neural synchronization. The comparison with other phase-based methods has been involved in the discussion session. CONCLUSIONS: Our findings suggest that neural synchronization carries subject-specific information, which can be captured by phase locking value. The incorporation of phase information into connectomes presents a promising approach to understand each individual brain's uniqueness.


Assuntos
Conectoma , Encéfalo/diagnóstico por imagem , Conectoma/métodos , Individualidade , Imageamento por Ressonância Magnética/métodos , Rede Nervosa
19.
J Oncol ; 2022: 8809469, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035484

RESUMO

Recent studies have demonstrated the utility and superiority of DNA repair-related genes as novel biomarkers for cancer diagnosis, prognosis, and therapy. Here, we aimed to screen the potential survival-related DNA repair-related genes in thyroid cancer (TC). TCGA datasets were utilized to analyze the differentially expressed DNA repair-related genes between TC and nontumor tissues. The K-M approach and univariate analysis were employed to screen survival-related genes. RT-PCR was employed to examine the expression of DNA repair-related genes in TC samples and matched noncancer samples. CCK-8 analyses were used to determine cellular proliferation. Herein, our team discovered that the expression of four DNA repair-related genes was remarkably upregulated in TC samples in contrast to noncancer samples. Survival assays identified 14 DNA repair-related genes. In our cohort, we observed that the expression of TAF13 and DCTN4 was distinctly elevated in TC specimens in contrast to nontumor specimens. Moreover, knockdown of TAF13 and DCTN4 was observed to inhibit the TC cellular proliferation. Overall, the upregulation of TAF13 and DCTN4 is related to decreased overall survival in TC patients. Therefore, the assessment of TAF13 and DCTN4 expression may be useful for predicting prognosis in these patients.

20.
Plants (Basel) ; 10(11)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34834604

RESUMO

Invasive species are a subset of naturalized species, and naturalized species are a subset of alien species. Determining the relationship among these three assemblages would be helpful in predicting and preventing biological invasion. Here, we reviewed the families, lifeforms, origins, introduction pathways and phylogenetic diversity of alien, naturalized and invasive vascular plants in China. The results show that species in the Asteraceae, Fabaceae and Poaceae families had a high dominance among alien, naturalized and invasive species. Moreover, almost all alien species in the Amaranthaceae, Solanaceae, Convolvulaceae and Euphorbiaceae families became naturalized species, and about 26.7% of the naturalized species became invasive species. Perennial herbs comprised a higher proportion of alien species than did annual herbs, though annual herbs were more suited to becoming invasive than perennial herbs. A considerable proportion (57.8%) of invasive species were introduced from America. More than half (56.5%) of alien species were introduced for their ornamental value, and half of these have become naturalized in China. Moreover, about half (55.2%) of all invasive species were introduced for their economic value (including ornamental, foraging and medicinal purposes). Invasive species were phylogenetically clustered and phylogenetically distant from alien and naturalized species, which indicates that phylogenetic differences could be helpful in becoming invasive. There is no doubt that human activity plays a significant role in biological invasion. This study suggests that when introducing alien species to a region, decision-makers should certainly consider the species' phylogeny, beyond just its fundamental characteristics.

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