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1.
Front Bioeng Biotechnol ; 9: 662418, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34820359

RESUMO

Tissue engineering is an emerging discipline that combines engineering and life sciences. It can construct functional biological structures in vivo or in vitro to replace native tissues or organs and minimize serious shortages of donor organs during tissue and organ reconstruction or transplantation. Organ transplantation has achieved success by using the tissue-engineered heart, liver, kidney, and other artificial organs, and the emergence of tissue-engineered bone also provides a new approach for the healing of human bone defects. In recent years, tissue engineering technology has gradually become an important technical method for dentistry research, and its application in stomatology-related research has also obtained impressive achievements. The purpose of this review is to summarize the research advances of tissue engineering and its application in stomatology. These aspects include tooth, periodontal, dental implant, cleft palate, oral and maxillofacial skin or mucosa, and oral and maxillofacial bone tissue engineering. In addition, this article also summarizes the commonly used cells, scaffolds, and growth factors in stomatology and discusses the limitations of tissue engineering in stomatology from the perspective of cells, scaffolds, and clinical applications.

2.
Clin Neurol Neurosurg ; 211: 107023, 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34800814

RESUMO

Alexander disease (AxD) is a rare, autosomal dominant genetic disorder with an incidence of approximately 1 in 27,00.000. It is caused by a missense mutation in the GFAP gene encoding the glial fibrillary acidic protein. Fragile X-associated tremor/ataxia syndrome (FXTAS) is an X-linked dominant genetic disease, usually caused by a pre-mutation: an unmethylated expansion in the range of 50-200 CGG repeats in the fragile X mental retardation 1 (FMR1) gene. The clinical manifestations of these two diseases are complex and have some similarities. Both type II AxD and FXTAS may have ataxia as the first symptom. Here, we describe a case of type II AxD with ataxia as the first symptom accompanying a hemizygous mutation in the FMR1 gene (NM_001185081, exon13, c 0.1256C>T, p.T419M, g 0.147026507C>T). A sporadic genetic mutation led us to misdiagnose the patient with FXTAS initially. Whole-genome sequencing confirmed a heterozygous mutation in the GFAP gene (NM_002055.5, exon4, c 0.1158C>A, p.N386K, g 0.6310C>A). This report indicates that when the patient's clinical manifestation is ataxia, and imaging results suggest that the midbrain, medulla oblongata, and other subcerebellar structures are atrophied, AxD should be considered. Whole-genome sequencing is thus feasible to avoid missed diagnoses and misdiagnoses.

3.
J Am Chem Soc ; 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34761937

RESUMO

Lithium-sulfur (Li-S) batteries constitute promising next-generation energy storage devices due to the ultrahigh theoretical energy density of 2600 Wh kg-1. However, the multiphase sulfur redox reactions with sophisticated homogeneous and heterogeneous electrochemical processes are sluggish in kinetics, thus requiring targeted and high-efficient electrocatalysts. Herein, a semi-immobilized molecular electrocatalyst is designed to tailor the characters of the sulfur redox reactions in working Li-S batteries. Specifically, porphyrin active sites are covalently grafted onto conductive and flexible polypyrrole linkers on graphene current collectors. The electrocatalyst with the semi-immobilized active sites exhibits homogeneous and heterogeneous functions simultaneously, performing enhanced redox kinetics and a regulated phase transition mode. The efficiency of the semi-immobilizing strategy is further verified in practical Li-S batteries that realize superior rate performances and long lifespan as well as a 343 Wh kg-1 high-energy-density Li-S pouch cell. This contribution not only proposes an efficient semi-immobilizing electrocatalyst design strategy to promote the Li-S battery performances but also inspires electrocatalyst development facing analogous multiphase electrochemical energy processes.

4.
Phys Rev E ; 104(4-1): 044303, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34781529

RESUMO

The phase transition of epidemic spreading model on networks is one of the most important concerns of physicists to theoretical epidemiology. In this paper, we present an analytical expression of epidemic threshold for interplay between epidemic spreading and human behavior on multiplex networks. The threshold formula proposed in this paper reveals the relation between the threshold on single-layer networks and that on multiplex networks, which means that the theoretical conclusions of single-layer networks can be used to improve the threshold accuracy of multiplex networks. To verify how well our formula works in different networks, we build a network model with constant total number of edges but gradually changing the heterogeneity of the network, from scale-free network to Erdos-Rényi random network. By use of theoretical analysis and computer simulations, we find that the heterogeneity of information layer behaves as a "double-edged sword" on the epidemic threshold: The strong heterogeneity can effectively improve the epidemic threshold (which means the disease outbreak requires a higher infection probability) when the awareness probability α is low, while the opposite effect takes place for high α. Meanwhile, the weak heterogeneity of the information layer is effective in suppressing the epidemic prevalence when the awareness probability is neither too high nor too low.

5.
Dalton Trans ; 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34796895

RESUMO

In this study, a metal-organic framework (ZIF-8)-derived nitrogen-doped carbon (C-ZIF)-modified g-C3N4 composite was directly prepared by pyrolysis. C-ZIF@g-C3N4 composites with different loadings were prepared by changing the precursor content. The charge transfer process that occurs at the interface of the ZIF-8-derived nitrogen-doped carbon/g-C3N4 heterostructures strongly hinders the recombination of photoinduced electron-hole pairs, thereby effectively enhancing the photocatalytic activity of C-ZIF@g-C3N4. Meanwhile, the unique hierarchical inorganic/organic heterostructure provides an abundance of active sites for photocatalytic reactions. Upon visible-light irradiation, C-ZIF@g-C3N4 with an optimal ratio of g-C3N4 to C-ZIF components exhibits both enhanced photocatalytic activity and excellent separability during the degradation of dye and hydrogen evolution compared to unmodified g-C3N4.

6.
Front Immunol ; 12: 759187, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34675937

RESUMO

Background: The concurrence of anti-contactin 1 (CNTN1) antibody-associated chronic inflammatory demyelinating polyneuropathy (CIDP) and membranous nephropathy (MN) has previously been reported in the literature. CIDP with autoantibodies against paranodal proteins are defined as autoimmune nodopathies (AN) in the latest research. In view of the unclear relationship between CIDP and MN, we performed a case study and literature review to investigate the clinical characteristics of anti-CNTN antibody-associated AN with MN. Methods: We detected antibodies against NF155, NF186, CNTN1, CNTN2, CASPR1 and PLA2R in blood samples of a patient with clinically manifested MN and concomitant peripheral neuropathy via double immunofluorescence staining and conducted a quantitative measurement of anti-PLA2R IgG antibodies via enzyme-linked immunosorbent assay (ELISA). Case reports of anti-CNTN1 antibody-associated AN, anti-CNTN1 antibody-associated AN with MN, and CIDP with MN were retrieved through a literature search for a comparative analysis of clinical characteristics. The cases were grouped according to the chronological order of CIDP and MN onset for the comparison of clinical characteristics. Results: A 57-year-old man with anti-PLA2R positive MN was admitted to the hospital due to limb numbness, weakness, and proprioceptive sensory disorder. He was diagnosed with anti-CNTN1 antibody-associated AN and recovered well after immunotherapy. Our literature search returned 22 cases of CIDP with MN that occurred before, after, or concurrently with CIDP. Good responses were achieved with early single-agent or combination immunotherapy, but eight out of the 22 patients with CIDP and concomitant MN ultimately developed different motor sequelae. Five patients had anti-CNTN1 antibody-associated AN with MN. Among these patients, males accounted for the majority of cases (male:female=4:1), the mean age at onset was late (60.2 ± 15.7 years, range 43-78 years), and 40% had acute to subacute onset. Clinical manifestations included sensory-motor neuropathy, sensory ataxia caused by proprioceptive impairment, and elevated cerebrospinal fluid protein levels. Conclusion: The age at onset of CIDP with MN was earlier than that of anti-CNTN1 antibody-associated AN. MN may occur before, after or concurrently with CIDP. The early detection and isotyping of anti-CNTN1 and anti-PLA2R antibodies and the monitoring of isotype switching may be essential for suspected CIDP patients.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34657305

RESUMO

Intraplantar injection of formalin produces persistent spontaneous nociception and hyperalgesia. The underlying mechanism, however, remains unclear. The present study was, therefore, designed to determine the roles of peripheral group III metabotropic glutamate receptors (mGluRs) in formalin-evoked spontaneous nociception. Pre-treatment with intraplantar injections of L-serine-O-phosphate (L-SOP), a group III mGluRs agonist, significantly inhibited formalin-induced nociceptive behaviours and decreased Fos production in the spinal dorsal horn. The inhibitory effects of L-SOP were abolished completely by pre-treatment with the group III mGluR antagonist (RS)-a-methylserine-O-phosphate (M-SOP). These data suggest that the activation of group III mGluRs in the periphery may play a differential role in formalin-induced nociception. In addition, L-SOP decreased the formalin-induced upregulation of tumour necrosis factor-α (TNF-α) as well as interleukine-1ß (IL-1ß) expression in the spinal cord, suggesting that activation of peripheral group III mGluRs reduces formalin-induced nociception through inhibition of the pro-inflammatory cytokines in the spinal cord. Therefore, the agonists acting peripheral group III mGluRs possess therapeutic effectiveness in chronic pain.

8.
Zhongguo Zhong Yao Za Zhi ; 46(18): 4749-4756, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34581085

RESUMO

The 95% ethanol extract of Baphicacanthis Cusiae Rhizoma et Radix was purified by multi-chromatographic methods including microporous resin, silica gel, Sephadex LH-20, and C_(18) reversed-phase column chromatography. Fourteen compounds were isolated and structurally identified, including five phenylethanoid glycosides, five phenylpropanoids, one lupinane triterpene, two alkaloids, and one flavonoid, listed as follows: 2-(4-hydroxy-3-methoxyphenyl)-3-(2-hydroxy-5-methoxyphenyl)-3-oxo-1-propanol B(1), threo-2,3-bis-(4-hydroxy-3-methoxybenzene)-3-methoxypropanol(2), 2-(3-hydroxy-4-methoxyphenyl)-ethanol-1-O-[3,4-O-di-acetyl-(1→3)-O-α-L-rhamnopyranosyl]-ß-D-glucopyranoside(3), verbascoside(4), 2″,3″-di-O-acetyl martynoside(5),(+)-pinore-sinol(6), diospyrosin(7), daidzein(8), wiedemannioside B(9), buddlenol A(10), 2″-O-acetyl martyonside(11), lupeol(12), indirubin(13), and tryptanthrin(14). Compound 3 was a new phenylethanoid glycoside, and the other 10 compounds were isolated for the first time from Baphicacanthis Cusiae Rhizoma et Radix except compounds 12, 13, and 14.


Assuntos
Glicosídeos Cardíacos , Álcool Feniletílico , Flavonoides , Glicosídeos , Estrutura Molecular , Rizoma
9.
World J Gastroenterol ; 27(31): 5232-5246, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34497447

RESUMO

BACKGROUND: Artificial intelligence in colonoscopy is an emerging field, and its application may help colonoscopists improve inspection quality and reduce the rate of missed polyps and adenomas. Several deep learning-based computer-assisted detection (CADe) techniques were established from small single-center datasets, and unrepresentative learning materials might confine their application and generalization in wide practice. Although CADes have been reported to identify polyps in colonoscopic images and videos in real time, their diagnostic performance deserves to be further validated in clinical practice. AIM: To train and test a CADe based on multicenter high-quality images of polyps and preliminarily validate it in clinical colonoscopies. METHODS: With high-quality screening and labeling from 55 qualified colonoscopists, a dataset consisting of over 71000 images from 20 centers was used to train and test a deep learning-based CADe. In addition, the real-time diagnostic performance of CADe was tested frame by frame in 47 unaltered full-ranged videos that contained 86 histologically confirmed polyps. Finally, we conducted a self-controlled observational study to validate the diagnostic performance of CADe in real-world colonoscopy with the main outcome measure of polyps per colonoscopy in Changhai Hospital. RESULTS: The CADe was able to identify polyps in the test dataset with 95.0% sensitivity and 99.1% specificity. For colonoscopy videos, all 86 polyps were detected with 92.2% sensitivity and 93.6% specificity in frame-by-frame analysis. In the prospective validation, the sensitivity of CAD in identifying polyps was 98.4% (185/188). Folds, reflections of light and fecal fluid were the main causes of false positives in both the test dataset and clinical colonoscopies. Colonoscopists can detect more polyps (0.90 vs 0.82, P < 0.001) and adenomas (0.32 vs 0.30, P = 0.045) with the aid of CADe, particularly polyps < 5 mm and flat polyps (0.65 vs 0.57, P < 0.001; 0.74 vs 0.67, P = 0.001, respectively). However, high efficacy is not realized in colonoscopies with inadequate bowel preparation and withdrawal time (P = 0.32; P = 0.16, respectively). CONCLUSION: CADe is feasible in the clinical setting and might help endoscopists detect more polyps and adenomas, and further confirmation is warranted.


Assuntos
Pólipos do Colo , Aprendizado Profundo , Inteligência Artificial , Pólipos do Colo/diagnóstico por imagem , Colonoscopia , Computadores , Humanos
10.
Zhongguo Zhong Yao Za Zhi ; 46(12): 3058-3065, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467696

RESUMO

In this study, the compound search was completed through SciFinder and CNKI databases, and the drug-like properties were screened in FAFdrugs4 and SEA Search Server databases. In addition, based on the target sets related to acute myocardial ischemia(AMI) searched in disease target databases such as OMIM database, GeneCards database and DrugBank, a network diagram of chemical component-target-pathway-disease was established via Cytoscape to predict the potential active components of Corydalis Herba, a traditional Tibetan herbal medicine which derived from the aerial parts of Corydalis hendersonii and C. mucronifera against AMI. A protein-protein interaction(PPI) network was constructed through the STRING database and the core targets in the network were predicted. And the enrichment analyses of core targets were completed by DAVID database and R software. Furthermore, a molecular docking method was used to verify the binding of the components with core targets using softwares such as Autodock Vina. The present results showed that there were 60 compounds related to AMI in Corydalis Herba, involving 73 potential targets. The GO functional enrichment analysis obtained 282 biological processes(BP), 49 cell components(CC) and 78 molecular functions(MF). KEGG was enriched into 85 pathways, including alcoholism pathway, endocrine resistance pathway, calcium signaling pathway, cAMP signaling pathway, vascular endothelial growth factor signaling pathway and adrenergic signaling transduction pathway of myocardial cells. The results of network topology analysis showed that the key components of anti-AMI of Corydalis Herba might be tetrahydropalmatine, etrahydrocolumbamine, N-trans-feruloyloctopamine, N-cis-p-coumaroyloctopamine, N-trans-p-coumaroylnoradrenline and N-trans-p-coumaroyloctopamine, and their core targets might be CDH23, SCN4 B and NFASC. The results of molecular docking showed that the key components of Corydalis Herba had stable binding activity with the core targets. This study provides reference for further elucidation of the pharmacological effects of Corydalis Herba against AMI, subsequent clinical application, and development.


Assuntos
Corydalis , Medicamentos de Ervas Chinesas , Isquemia Miocárdica , Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Tibetana , Simulação de Acoplamento Molecular , Isquemia Miocárdica/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular
11.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3356-3363, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34396755

RESUMO

With Sangtang Yin granule as model drug,and based on the strategy of " unification of medicines and excipients",the feasibility of preparing high drug loading granules with traditional Chinese medicine( TCM) raw powder as carrier was explored. The powder yield,particle size and particle size distribution,fillibility,flowability,hygroscopicity,reconstituability and other key physical properties relating to preparations of 8 herbs( Dioscoreae Rhizoma,Euryales Semen,Atractylodis Macrocephalae Rhizoma,Coicis semen,Poria,Puerariae Lobatae Radix,Puerariae Thomsonii Radix and Coicis Semen by stir-frying with bran) were studied after being smashed,and the feasibility of taking them as excipients of TCM granules was evaluated by co-spray drying,dry granulation and other preparation techniques. According to the results of the physical properties of raw powders,raw powders of Dioscoreae Rhizoma,Euryales Semen and Puerariae Thomsonii Radix had a high powder yield,uniform particle size distribution,good fillibility,poor hygroscopicity and good reconstitutability,with the feature of assisting granule forming. Compared with the prescription of spray dry powder Sangtang Yin without any excipient,the co-sprayed powder had a high yield,good fillibility and compressibility. The yield of dry granules prepared by co-spraying dry powder was increased by more than 10%,and the particles had a uniform color,good fluidity and dissolubility with the drug-loading rate up to 100%. Based on the physical characteristics of TCM raw powder combined with the analysis of the preparation process,Dioscoreae Rhizoma and Puerariae Thomsonii Radix raw powder were selected as the carriers of granule preparations,and Sangtang Yin granule without any excipient was successfully prepared. The findings provide a feasible idea for the preparation of TCM granules with a high drug loading capacity.


Assuntos
Medicina Tradicional Chinesa , Pueraria , Excipientes , Tamanho da Partícula , Pós , Rizoma
12.
Accid Anal Prev ; 161: 106330, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34419652

RESUMO

To ensure safety, it is necessary to test the connected vehicle (CV) technology before application. The goal of this study is to provide a case reference for the testing of the connected vehicle technology. The connected vehicle technology test platform is built based on the driving simulator. Taking fog zone, tunnel zone, and work zone as analysis cases, drivers were invited to participate in driving simulation experiments, related data was collected, and the impact of connected vehicle technology on driving behavior and safety was analyzed. The results of the fog zone imply that drivers have a high degree of compliance with the connected vehicle technology. However, it also increases the visual workload of drivers to a certain extent. The results of the tunnel zone indicate that the connected vehicle technology can enhance driving safety by enabling drivers to remain cautious. The results of the work zone demonstrate that the connected vehicle technology is able to promote drivers' ability of controlling speed and lane-changing. Overall, the results show that the connected vehicle technology has a positive effect on enhancing driving behavior and safety. The research framework and the development of the connected vehicle technology test platform based on the driving simulator given in the paper are dynamic and reproducible, which provides a reference for researchers in related fields, and the case analysis in this paper enriches the research of connected vehicle technology.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Acidentes de Trânsito/prevenção & controle , Simulação por Computador , Humanos , Tecnologia
13.
Sensors (Basel) ; 21(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34450894

RESUMO

Emotion recognition is an important research field for human-computer interaction. Audio-video emotion recognition is now attacked with deep neural network modeling tools. In published papers, as a rule, the authors show only cases of the superiority in multi-modality over audio-only or video-only modality. However, there are cases of superiority in uni-modality that can be found. In our research, we hypothesize that for fuzzy categories of emotional events, the within-modal and inter-modal noisy information represented indirectly in the parameters of the modeling neural network impedes better performance in the existing late fusion and end-to-end multi-modal network training strategies. To take advantage of and overcome the deficiencies in both solutions, we define a multi-modal residual perceptron network which performs end-to-end learning from multi-modal network branches, generalizing better multi-modal feature representation. For the proposed multi-modal residual perceptron network and the novel time augmentation for streaming digital movies, the state-of-the-art average recognition rate was improved to 91.4% for the Ryerson Audio-Visual Database of Emotional Speech and Song dataset and to 83.15% for the Crowd-Sourced Emotional Multi Modal Actors dataset. Moreover, the multi-modal residual perceptron network concept shows its potential for multi-modal applications dealing with signal sources not only of optical and acoustical types.


Assuntos
Emoções , Redes Neurais de Computação , Humanos , Filmes Cinematográficos , Fala
14.
Korean J Physiol Pharmacol ; 25(5): 425-437, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34448460

RESUMO

Although the contributions of sitagliptin to endothelial dysfunction in diabetes mellitus were previously reported, the mechanisms still undefined. Autophagy plays an important role in the development of diabetes mellitus, but its role in diabetic macrovascular complications is unclear. This study aims to observe the effect of sitagliptin on macrovascular endothelium in diabetes and explore the role of autophagy in this process. Diabetic rats were induced through administration of high-fat diet and intraperitoneal injection of streptozotocin. Then diabetic rats were treated with or without sitagliptin for 12 weeks. Endothelial damage and autophagy were measured. Human umbilical vein endothelial cells were cultured either in normal glucose or in high glucose medium and intervened with different concentrations of sitagliptin. Rapamycin was used to induce autophagy. Cell viability, apoptosis and autophagy were detected. The expressions of proteins in c-Jun N-terminal kinase (JNK)-Bcl-2-Beclin-1 pathway were measured. Sitagliptin attenuated injuries of endothelium in vivo and in vitro. The expression of microtubuleassociated protein 1 light chain 3 II (LC3II) and beclin-1 were increased in aortas of diabetic rats and cells cultured with high-glucose, while sitagliptin inhibited the over-expression of LC3II and beclin-1. In vitro pre-treatment with sitagliptin decreased rapamycin-induced autophagy. However, after pretreatment with rapamycin, the protective effect of sitagliptin on endothelial cells was abolished. Further studies revealed sitagliptin increased the expression of Bcl-2, while inhibited the expression of JNK in vivo. Sitagliptin attenuates injuries of vascular endothelial cells caused by high glucose through inhibiting over-activated autophagy. JNK-Bcl-2-Beclin-1 pathway may be involved in this process.

15.
Cell Mol Gastroenterol Hepatol ; 13(1): 57-79, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34418587

RESUMO

BACKGROUND & AIMS: Microbiota dysbiosis and mucosa-associated bacteria are involved in colorectal cancer progression. We hypothesize that an interaction between virulent pathobionts and epithelial defense promotes tumorigenesis. METHODS: Chemical-induced CRC mouse model was treated with antibiotics at various phases. Colonic tissues and fecal samples were collected in a time-serial mode and analyzed by gene microarray and 16S rRNA sequencing. Intraepithelial bacteria were isolated using a gentamicin resistance assay, and challenged in epithelial cultures. RESULTS: Our study showed that antibiotic treatment at midphase but not early or late phase reduced mouse tumor burden, suggesting a time-specific host-microbe interplay. A unique antimicrobial transcriptome profile showing an inverse relationship between autophagy and oxidative stress genes was correlated with a transient surge in microbial diversity and virulence emergence in mouse stool during cancer initiation. Gavage with fimA/fimH/htrA-expressing invasive Escherichia coli isolated from colonocytes increased tumor burden in recipient mice, whereas inoculation of bacteria deleted of htrA or triple genes did not. The invasive E.coli suppressed epithelial autophagy activity through reduction of microtubule-associated protein 1 light-chain 3 transcripts and caused dual oxidase 2-dependent free radical overproduction and tumor cell hyperproliferation. A novel alternating spheroid culture model was developed for sequential bacterial challenge to address the long-term changes in host-microbe interaction for chronic tumor growth. Epithelial cells with single bacterial encounter showed a reduction in transcript levels of autophagy genes while those sequentially challenged with invasive E.coli showed heightened autophagy gene expression to eliminate intracellular microbes, implicating that bacteria-dependent cell hyperproliferation could be terminated at late phases. Finally, the presence of bacterial htrA and altered antimicrobial gene expression were observed in human colorectal cancer specimens. CONCLUSIONS: Invasive pathobionts contribute to cancer initiation during a key time frame by counterbalancing autophagy and oxidative stress in the colonic epithelium. Monitoring gut microbiota and antimicrobial patterns may help identify the window of opportunity for intervention with bacterium-targeted precision medicine.

16.
Oxid Med Cell Longev ; 2021: 5570731, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34394827

RESUMO

Background: Ulcerative colitis (UC) is a chronic inflammatory disease with increasing prevalence worldwide. Barrier defect in intestinal epithelial cells (IECs) is one of the main pathogeneses in UC. Pyroptosis is a programmed lytic cell death and is triggered by inflammatory caspases, while little is known about its role in UC. Methods: Differentially expressed genes (DEGs) were identified by comparing UC patients with healthy controls from the GEO datasets. The candidate genes involved in pyroptosis were obtained, and the underlying molecular mechanism in the progression of UC was explored in vivo and in vitro. Results: Pleckstrin homology domain leucine-rich repeat protein phosphatase 2 (PHLPP2), a protein phosphatase, was downregulated and involved in regulating inflammation-induced IEC pyroptosis by modulating the NF-κB signaling in UC through bioinformatics analysis. Moreover, we demonstrated that PHLPP2 was downregulated in UC patients and UC mice. Besides, we found that PHLPP2 depletion activated the NF-κB signaling and increased the expressions of caspase-1 P20, Gasdermin N, IL-18, and IL-1ß contributing to IEC pyroptosis and inflammation in UC mice. Furthermore, we found that PHLPP2-/- mice developed hypersensitivity to dextran sulfate sodium (DSS) treatment toward colitis showing activated NF-κB signaling and dramatically induced expressions of caspase-1 P20, Gasdermin N, IL-18, and IL-1ß. Mechanically, this inflammation-induced downregulation of PHLPP2 was alleviated by an NF-κB signaling inhibitor in intestinal organoids of PHLPP2-/- mice and fetal colonic cells. Conclusions: PHLPP2 downexpression activated the NF-κB signaling and promoted the IEC pyroptosis, leading to UC progression. Therefore, PHLPP2 might be an attractive candidate therapeutic target for UC.

17.
Medicine (Baltimore) ; 100(33): e27022, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34414996

RESUMO

RATIONALE: The clinical manifestations of basilar dolichoectasia (BD) are variable. The diagnosis is based on imaging measurements. Digital subtraction angiography displays only the dilated vascular lumen and lacks visualization of the arterial wall. High-resolution Magnetic resonance imaging (MRI) can identify intramural hematoma; therefore, it may be more suitable for the imaging evaluation of BD. However, most of the existing literature pertaining to BD lacks vascular wall assessment. PATIENT CONCERNS: A 65-year-old Chinese man perceived weakness of the left upper and lower limb, double vision, dizziness, nausea, and vomiting was admitted to the emergency department. Fifteen years prior to this admission, he began taking levamlodipine besylate inconsistently for hypertension, but the level of blood pressure control was uncertain. The patient's father had a family history of hypertension. DIAGNOSES: An emergency axial computed tomography scan of the brain showed basilar artery (BA) dilation. Computed tomography angiography further indicated a maximum BA diameter of 38.94 mm. The length was >182 mm. MRI revealed acute infarctions of the right medulla oblongata and pons. Meanwhile, the patient had evidence of cerebral small vessel disease, including cerebral microbleeds and white matter hyperintensities. Whole-exome sequencing eliminated significant genetic variations consistent with clinical phenotypes. BD and intramural hematoma were further confirmed by high-resolution MRI of the arterial wall. INTERVENTIONS: Atorvastatin was admitted according to the results of the high-resolution MRI of the arterial wall. Benidipine hydrochloride was selected as a long-term anti-hypertensive drug. OUTCOMES: The patient had no symptoms of neurological damage during 3-month follow-up. LESSONS: Current evidence shows that BD has no obvious correlation with atherosclerosis. BA dissection and uncontrolled hypertension may be important factors in the progression of BD. BD-related stroke is likely to recur, and there are no standard secondary prevention measures. BD is often accompanied by cerebral microbleeds, and bleeding risk must be assessed during secondary prevention. When the BA diameter is greater than 10 mm, anti-platelet medication should be used with caution, blood pressure should be strictly controlled, and endovascular treatment should be considered.


Assuntos
Hematoma/etiologia , Insuficiência Vertebrobasilar/complicações , Idoso , Hemorragia Cerebral/fisiopatologia , Angiografia por Tomografia Computadorizada/métodos , Hematoma/fisiopatologia , Humanos , Masculino , Insuficiência Vertebrobasilar/fisiopatologia
18.
Br J Neurosurg ; : 1-5, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34435533

RESUMO

Contrast-induced encephalopathy (CIE) is a rare complication of angiography. According to our knowledge, the majority of CIE reports is imaging observations and rarely includes results of cerebrospinal fluid (CSF) tests. Furthermore, among the cases reporting the data for CSF testing, most of the results were normal. Here, we report a case of CIE presenting with significantly elevated levels of CSF protein. We found that the course of improvement in brain imaging findings was not consistent with the severity of clinical manifestations. The diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) sequences were normal. Considering the lack of convenient direct indicators to observe blood-brain barrier (BBB) function, changes in the levels of CSF protein may be related to BBB permeability and recovery and may serve as a potential prognostic marker.

19.
Int J Stem Cells ; 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34456192

RESUMO

Background and Objectives: Human umbilical cord mesenchymal stem cells (HUC-MSCs) are promising candidates for cell-based therapy in regenerative medicine or other diseases due to their superior characteristics, including higher proliferation, faster self-renewal ability, lower immunogenicity, a noninvasive harvest procedure, easy expansion in vitro, and ethical access, compared with stem cells from other sources. Methods and Results: In the present study, we knocked down the expression of SOX9 in HUC-MSCs by lentivirus interference and found that knockdown of SOX9 inhibited the proliferation and migration of HUC-MSCs and influenced the expression of cytokines (IL-6 and IL-8), growth factors (GM-CSF and VEGF) and stemness-related genes (OCT4 and SALL4). In addition, the repair effect of skin with burn injury in rats treated with HUC-MSCs transfected with sh-control was better than that rats treated with HUC-MSCs transfected with shSOX9 or PBS, and the accessory structures of the skin, including hair follicles and glands, were greater than those in the other groups. We found that knockdown of the expression of SOX9 obviously inhibited the expression of Ki67, CK14 and CK18. Conclusions: In conclusion, this study will provide a guide for modifying HUC-MSCs by bioengineering technology in the future.

20.
J Hematol Oncol ; 14(1): 109, 2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34246306

RESUMO

BACKGROUND: The prognosis for diffuse gliomas is very poor and the mechanism underlying their malignant progression remains unclear. Here, we aimed to elucidate the role and mechanism of the RNA N6,2'-O-dimethyladenosine (m6A) reader, YTH N6-methyladenosine RNA binding protein 2 (YTHDF2), in regulating the malignant progression of gliomas. METHODS: YTHDF2 mRNA levels and functions were assessed using several independent datasets. Western blotting, quantitative polymerase chain reaction, and immunohistochemistry were used to evaluate the expression levels of YTHDF2 and other molecules in human and mouse tumor tissues and cells. Knockdown and overexpression were used to evaluate the effects of YTHDF2, methyltransferase-like 3 (METTL3), and UBX domain protein 1 (UBXN1) on glioma malignancy in cell and orthotopic xenograft models. RNA immunoprecipitation (RIP), methylated RIP, and RNA stability experiments were performed to study the mechanisms underlying the oncogenic role of YTHDF2. RESULTS: YTHDF2 expression was positively associated with a higher malignant grade and molecular subtype of glioma and poorer prognosis. YTHDF2 promoted the malignant progression of gliomas in both in vitro and in vivo models. Mechanistically, YTHDF2 accelerated UBXN1 mRNA degradation via METTL3-mediated m6A, which, in turn, promoted NF-κB activation. We further revealed that UBXN1 overexpression attenuated the oncogenic effect of YTHDF2 overexpression and was associated with better survival in patients with elevated YTHDF2 expression. CONCLUSIONS: Our findings confirmed that YTHDF2 promotes the malignant progression of gliomas and revealed important insight into the upstream regulatory mechanism of NF-κB activation via UBXN1 with a primary focus on m6A modification.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Glioma/genética , Metiltransferases/genética , NF-kappa B/metabolismo , Estabilidade de RNA , Proteínas de Ligação a RNA/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Animais , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , Glioma/patologia , Humanos , Metiltransferases/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo
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