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1.
Sensors (Basel) ; 20(5)2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32131489

RESUMO

At present, the method of two-dimensional image recognition is mainly used to detect the abnormal fastener in the rail-track inspection system. However, the too-tight-or-too-loose fastener condition may cause the clip of the fastener to break or loose due to the high frequency vibration shock, which is difficult to detect from the two-dimensional image. In this practical application background, 3D visual detection technology provides a feasible solution. In this paper, we propose a fundamental multi-source visual data detection method, as well as an accurate and robust fastener location and nut or bolt segmentation algorithm. By combining two-dimensional intensity information and three-dimensional depth information generated by the projection of line structural light, the locating of nut or bolt position and accurate perception of height information can be realized in the dynamic running environment of railway. The experimental results show that the static measurement accuracy in the vertical direction using the structural light vision sensor is 0.1 mm under the laboratory condition, and the dynamic measurement accuracy is 0.5 mm under the dynamic train running environment. We use dynamic template matching algorithm to locate fasteners from 2D intensity map, which achieves 99.4% accuracy, then use the watershed algorithm to segment the nut and bolt from the corresponding depth image of located fastener. Finally, the 3D shape of the nut and bolt is analyzed to determine whether the nut or bolt height meets the local statistical threshold requirements, so as to detect the hidden danger of railway transportation caused by too loose or too tight fasteners.

2.
Zhongguo Gu Shang ; 33(2): 190-4, 2020 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-32133823

RESUMO

Hypoxic-ischemic encephalopathy (HIE) is the leading cause of neonatal death and neurodevelopmental disorders in infants. Part of patients have different degrees of neurological sequelae, such as cerebral palsy, cognitive and motor function development disorders. Hypoxia-ischemia may activate JAK2/STAT3 signaling pathway, which leads to the microglia activation and neuroinflammation. Down-Regulating JAK2/STAT3 signaling pathway can inhibit microglia activation and regulate the inflammatory injury of nervous system. At present, the treatment of hypoxic ischemic encephalopathy is limited, so the study of regulatory mechanism about microglia activation has important value for the treatment of hypoxic-ischemic encephalopathy. This paper summarizes the role of JAK2/STAT3 signaling pathway in microglia activation and analyzes the relationship between them, in order to provide new ideas and strategies for treatment on hypoxic-ischemic encephalopathy.


Assuntos
Hipóxia-Isquemia Encefálica , Microglia , Encéfalo , Humanos , Janus Quinase 2 , Fator de Transcrição STAT3 , Transdução de Sinais
3.
Thorac Cancer ; 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32130756

RESUMO

BACKGROUND: We aimed to obtain a set of health state utility scores of patients with esophageal cancer (EC) and precancerous lesions in China, and to explore the influencing factors of health-related quality of life (HRQoL). METHODS: A hospital-based multicenter cross-sectional study was conducted. From 2013 to 2014, patients with EC or precancerous lesions were enrolled. HRQoL was assessed using a European quality of life-5 dimension (EQ-5D-3L) instrument. Multivariable linear regression analysis was performed to explore the influencing factors of the EQ-5D utility scores. RESULTS: A total of 2090 EC patients and 156 precancer patients were included in the study. The dimension of pain/discomfort had the highest rate of self-reported problems, 60.5% in EC and 51.3% in precancer patients. The mean visual analog scale (VAS) score for EC and precancer patients were 68.4 ± 0.7 and 64.5 ± 3.1, respectively. The EQ-5D utility scores for EC and precancer patients were estimated as 0.748 ± 0.009 and 0.852 ± 0.022, and the scores of EC at stage I, stage II, stage III, and stage IV were 0.693 ± 0.031, 0.747 ± 0.014, 0.762 ± 0.015, and 0.750 ± 0.023, respectively. According to the multivariable analyses, the factors of region, occupation, household income in 2012, health care insurance type, pathological type, type of therapy, and time points of the survey were statistically associated with the EQ-5D utility scores of EC patients. CONCLUSIONS: There were remarkable decrements of utility scores among esophageal cancer patients, compared with precancer patients. The specific utility scores of EC would support further cost-utility analysis in populations in China.

4.
Mol Ecol Resour ; 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32216061

RESUMO

Ancherythroculter nigrocauda is a cyprinid fish endemic of the Upper Reaches of the Yangtze River in China, where it is an important aquaculture and commercial species. On the other hand, A. nigrocauda is a threatened species as a result of overfishing, dam construction, and water pollution. In this study, a chromosome-level genome assembly of A. nigrocauda is reported and built using PacBio sequencing and the Hi-C technology. The 1.04 Gb sequenced genome of A. nigrocauda contained 2,403 contigs, with an N50 length of 3.12 Mb. Then, 1,297 contigs, which represented 54.0% of all the numbers of contigs and 97.2% of the whole content of genome nucleotide base, were assembled into 24 chromosomes. Combined with transcriptome data from 10 tissues, 27,042 (78.5%) genes were functionally annotated out of 34,414 predicted protein-coding genes. Interestingly, highly expression of many positively selected genes and expanded gene families in brain suggested that these genes might play important roles in the brain development of A. nigrocauda. Finally, we found tissue-specific expression of 10,732 genes. Functional analyses showed that they were mainly composed of genes related to (i) environmental information processing, (ii) circulatory system and (iii) development, suggesting they might be important for adaptation to different environments and for development of A. nigrocauda. The high-quality genome obtained in this study will not only provide a valuable genomic resource for future studies of A. nigrocauda population and conservation, but also is an important resource for further functional genomics studies of fishes.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32219508

RESUMO

Disease outcome is associated with virulence factors of Helicobacter pylori (H. pylori), which are partially attributed to the outer membrane protein (OMP). This study aimed to investigate the correlation between the four OMP genes (babA, oipA, sabA, and homB) and gastroduodenal diseases. One hundred and seventy-seven H. pylori strains were isolated from Chinese patients with different gastroduodenal diseases (49 chronic gastritis, 19 gastric ulcer, 33 gastric cancer, and 76 duodenal ulcer), 94 of which contained pathological information (41 superficial gastritis, 24 intestinal hyperplasia, and 29 gastric adenocarcinoma). The full-length amplification of babA, oipA, sabA, and homB genes was acquired and sequenced. Then, the genetic polymorphism was analyzed to compare with the reference strains from the GenBank database. Functional status and cluster analysis were also performed to evaluate the impact of genetic polymorphism on disease outcome. The prevalence of babA, oipA, sabA, and homB genes were 91.5%, 100%, 94.0%, and 95.5%, respectively. The four OMP genes were characterized by genetic polymorphism and in the status of positive selection (Ka/Ks> 1). The proportion of strains with functional status on for oipA and sabA gene was 100% and 76.2%, respectively. The sequences of four OMP genes were mainly clustered together with the East Asian references. The four OMP genes were not different in patients with gastroduodenal diseases and pathologic changes (P > 0.05). H. pylori babA, oipA, sabA, and homB genes were common in the Chinese populations, but did not seem to be involved in the development of gastroduodenal diseases.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32219697

RESUMO

BACKGROUND AND OBJECTIVES: Driving under the influence of diazepam is increasing in China. The pharmacokinetics of diazepam and its metabolites, especially the glucuronide metabolites, are helpful in the identification of diazepam use by drivers. This study aimed to investigate the pharmacokinetics of diazepam and its metabolites (nordazepam, oxazepam, oxazepam glucuronide and temazepam glucuronide) in the blood of Chinese people, and to provide basic data for identifying diazepam use and estimating the time of last diazepam ingestion. METHODS: A total of 28 participants (14 men, 14 women) were recruited and each person received 5 mg diazepam orally. Whole blood was collected at 0 h (pre-dose), and 1 h, 2 h, 4 h, 8 h, 12 h, and 24 h, and at 2 days, 3 days, 6 days, 12 days, and 15 days post-dose. Analytes of interest were extracted via solid-phase extraction and analyzed by a liquid chromatography tandem mass spectrometry method operated in a positive multiple response monitoring mode. Pharmacokinetic parameters were analyzed by a pharmacokinetic software DAS according to the non-compartment model. The time of last diazepam use was estimated using the concentration ratios of diazepam to metabolites and metabolites to metabolites from controlled drug administration studies. RESULTS: The respective time of maximum concentration, the maximum concentration and the elimination half-life of diazepam were 1.04 ± 1.00 h, 87.37 ± 31.92 ng/mL and 129.07 ± 75.00 h; of nordazepam were 133.14 ± 109.63 h, 3.80 ± 1.75 ng/mL, and 229.73 ± 236.83 h; of oxazepam were 100.29 ± 87.16 h, 1.62 ± 2.64 ng/mL, and 382.86 ± 324.58 h; of temazepam glucuronide were 44.43 ± 55.41 h, 2.08 ± 0.88 ng/mL, and 130.53 ± 72.11 h; and of oxazepam glucuronide were 66.86 ± 56.33 h, 1.10 ± 0.41 ng/mL, and 240.66 ± 170.12 h. A good correlation model was obtained from the concentration ratio of diazepam to nordazepam and the time of diazepam use, and the prediction errors were less than 20%. CONCLUSIONS: This study provides a sensitive method to identify diazepam ingestion by monitoring diazepam and its metabolites including glucuronides, as well as to infer the time following oral consumption.

7.
BMC Complement Med Ther ; 20(1): 72, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32143602

RESUMO

BACKGROUND: Flavonoids from plant medicines are supposed to be viable alternatives for the treatment of type 2 diabetes (T2D) as less toxicity and side effects. Radix scutellariae (RS) is a widely used traditional medicine in Asia. It has shown great potential in the research of T2D. However, the pharmacological actions remain obscured due to the complex chemical nature of plant medicines. METHODS: In the present study, a systematic method combining ultrafiltration UPLC-TripleTOF-MS/MS and network pharmacology was developed to screen α-glucosidase inhibitors from flavonoids of RS, and explore the underlying mechanism for the treatment of T2D. RESULTS: The n-butanol part of ethanol extract from RS showed a strong α-glucosidase inhibition activity (90.55%, IC50 0.551 mg/mL) against positive control acarbose (90.59%, IC50 1.079 mg/mL). A total of 32 kinds of flavonoids were identified from the extract, and their ESI-MS/MS behaviors were elucidated. Thirteen compounds were screened as α-glucosidase inhibitors, including viscidulin III, 2',3,5,6',7-pentahydroxyflavanone, and so on. A compound-target-pathway (CTP) network was constructed by integrating these α-glucosidase inhibitors, target proteins, and related pathways. This network exhibited an uneven distribution and approximate scale-free property. Chrysin (k = 87), 5,8,2'-trihydroxy-7-methoxyflavone (k = 21) and wogonin (k = 20) were selected as the main active constituents with much higher degree values. A protein-protein interaction (PPI) weighted network was built for target proteins of these α-glucosidase inhibitors and drug targets of T2D. PPARG (Cd = 0.165, Cb = 0.232, Cc = 0.401), ACACB (Cd = 0.155, Cb = 0.184, Cc = 0.318), NFKB1 (Cd = 0.233, Cb = 0.161, Cc = 0.431), and PGH2 (Cd = 0.194, Cb = 0.157, Cc = 0.427) exhibited as key targets with the highest scores of centrality indices. Furthermore, a core subnetwork was extracted from the CTP and PPI weighted network. Type II diabetes mellitus (hsa04930) and PPAR signaling pathway (hsa03320) were confirmed as the critical pathways. CONCLUSIONS: These results improved current understanding of natural flavonoids on the treatment of T2D. The combination of ultrafiltration UPLC-TripleTOF-MS/MS and network pharmacology provides a novel strategy for the research of plant medicines and complex diseases.

8.
Glia ; 2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32112601

RESUMO

Microglia are a specialized population of tissue macrophages in the mammalian brain. Microglial phenotype is tightly regulated by local environmental factors, although little is known about these factors and their region-preferred roles in regulating local neuroinflammatory responses. We hypothesized that microglia in different brain regions respond differently to neuroinflammatory stimulation and that CD200, an anti-inflammatory protein mainly originated from neurons, acts as a local cue inhibiting microglia activation in the midbrain. We utilized a CD200-deficient mouse line to analyze the phenotypic role of CD200 in the regulation of normal neuron-microglia homeostasis in the midbrain and in the dopaminergic degeneration in an α-synuclein overexpression model of PD. We found that systemic administration of an endotoxin lipopolysaccharide induced a region-preferred change in CD200 expression in the midbrain. Similarly, CD200-/- mice showed a regional preference in an enhancement of microglia activation and baseline inflammatory levels in the midbrain and dopamine neuron loss in the substantia nigra (SN). In a mouse model of Parkinson's disease (PD) induced by rAAV-hSYN injection into the SN, CD200-/- mice showed more dopamine neuron loss in the SN than wild type mice. Activation of CD200 receptors with a CD200 fusion protein alleviated the neuroinflammation and neuronal death in the SN of PD mice. These findings demonstrate that CD200 is essential for the midbrain homeostasis and acts as a critical local regulator in controlling microglial properties related to the PD pathogenesis.

9.
J Biotechnol ; 311: 19-24, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32067982

RESUMO

Halohydrin dehalogenases (HHDHs) are valuable biocatalysts involved in the synthesis of ß-substituted alcohols via their nucleophile-mediated ring-opening activity. To use directed evolution to unleash the latent potential of HHDHs for the synthesis of ß-substituted alcohols, we report a high-throughput assay for screening HHDHs mutagenesis libraries. The assay is performed in a 96-well microtiter plate format using a cell-free extract or whole-cells in the presence of the desired nucleophile. The developed method relies upon the color change of bromothymol blue, due to the pH change caused by HHDH-catalyzed ring-opening of the epoxide substrate. The assay was validated using gas chromatography and subsequently applied to high-throughput screening of halohydrin dehalogenase HheC mutagenesis library. Active mutants were found for the tested substrates. Due to its simplicity and flexibility towards the use of nucleophiles and epoxides, the method is an attractive alternative to the existing assays for HHDH epoxide ring-opening reaction and could be helpful in the rapid discovery of industrial biocatalysts.

10.
Artigo em Inglês | MEDLINE | ID: mdl-32068268

RESUMO

Forkhead box R2 (FOXR2), a new member of the FOX family, is involved in a wide range of biological processes such as embryogenesis, differentiation, transformation and metabolic homeostasis. Recently, FOXR2 has been reported to be aberrantly expressed in a variety of cancers and correlated with cancer development. However, the specific role of FOXR2 in thyroid cancer (TC) remains unclear. In this study, we showed that FOXR2 was highly expressed in TC tissues and cell lines. Moreover, down-regulation of FOXR2 inhibited hypoxia-induced reactive oxygen species (ROS) production and migration/invasion of TC cells. We also found that the hedgehog pathway was responsible for the partial mechanisms underlying the inhibitory effect. Taken together, these findings indicated that down-regulation of FOXR2 inhibits hypoxia-driven ROS-induced migration and invasion of TC cells via regulation of the hedgehog pathway. Thus, FOXR2 may hold great potential for TC treatment.

11.
Sci Rep ; 10(1): 1945, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029845

RESUMO

Microhaplotypes are an emerging type of forensic genetic marker that are expected to support multiple forensic applications. Here, we developed a 124-plex panel for microhaplotype genotyping based on next-generation sequencing (NGS). The panel yielded intralocus and interlocus balanced sequencing data with a high percentage of effective reads. A full genotype was determined with as little as 0.1 ng of input DNA. Parallel mixture experiments and in-depth comparative analyses were performed with capillary-electrophoresis-based short tandem repeat (STR) and NGS-based microhaplotype genotyping, and demonstrated that microhaplotypes are far superior to STRs for mixture deconvolution. DNA from Han Chinese individuals (n = 256) was sequenced with the 124-plex panel. In total, 514 alleles were observed, and the forensic genetic parameters were calculated. A comparison of the forensic parameters for the 20 microhaplotypes with the top Ae values in the 124-plex panel and 20 commonly used forensic STRs showed that these microhaplotypes were as effective as STRs in identifying individuals. A linkage disequilibrium analysis showed that 106 of the 124 microhaplotypes were independently hereditary, and the combined match probability for these 106 microhaplotypes was 5.23 × 10-66. We conclude that this 124-plex microhaplotype panel is a powerful tool for forensic applications.

12.
Int J Infect Dis ; 93: 224-230, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32045697

RESUMO

OBJECTIVES: Bordetella pertussis is a highly contagious respiratory agent and is the causative pathogen of pertussis, which primarily affects children. Current diagnostic techniques for this pathogen have a variety of limitations including a long culture time, low bacterial load, and lack of specificity. METHODS: This article reports the development of a one-tube nested quantitative real-time PCR assay using the locked nucleic acid (LNA) technique (LNA-OTN-q-PCR), targeting the BP485 gene and using a simple inexpensive extraction method. A total of 130 clinical samples from patients with clinically suspected pertussis, collected from the Children's Hospital of Hebei, China, were tested by LNA-OTN-q-PCR assay. RT-PCR and two-step semi-nested PCR assays were performed in parallel for comparison. RESULTS: Only strains of B. pertussis were identified as positive, whereas all of the remaining strains were appropriately identified as negative by the LNA-OTN-q-PCR assay. A single copy per reaction can be detected by the LNA-OTN-q-PCR assay. Additionally, the sensitivity of this method was 100 times that of the RT-PCR assay (100 copies per reaction). Sixty-three of the 130 clinical samples were detected positive by LNA-OTN-q-PCR assay; in contrast, RT-PCR was able to detect only 41 positive samples. Following this, all 63 samples were positively identified by two-step semi-nested PCR. Compared with the two-step semi-nested PCR assay, both the specificity and sensitivity of the LNA-OTN-q-PCR assay using purified DNA and crude extract were 100%. CONCLUSIONS: This assay was able to detect B. pertussis infection with high sensitivity and specificity. This test shows great potential as a promising technique to detect B. pertussis in both clinical laboratories and public health settings.

13.
Int J Mol Sci ; 21(4)2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32070009

RESUMO

Following photosynthesis, sucrose is translocated to sink organs, where it provides the primary source of carbon and energy to sustain plant growth and development. Sugar transporters from the SWEET (sugar will eventually be exported transporter) family are rate-limiting factors that mediate sucrose transport across concentration gradients, sustain yields, and participate in reproductive development, plant senescence, stress responses, as well as support plant-pathogen interaction, the focus of this study. We identified 25 SWEET genes in the walnut genome and distinguished each by its individual gene structure and pattern of expression in different walnut tissues. Their chromosomal locations, cis-acting motifs within their 5' regulatory elements, and phylogenetic relationship patterns provided the first comprehensive analysis of the SWEET gene family of sugar transporters in walnut. This family is divided into four clades, the analysis of which suggests duplication and expansion of the SWEET gene family in Juglans regia. In addition, tissue-specific gene expression signatures suggest diverse possible functions for JrSWEET genes. Although these are commonly used by pathogens to harness sugar products from their plant hosts, little was known about their role during Xanthomonas arboricola pv. juglandis (Xaj) infection. We monitored the expression profiles of the JrSWEET genes in different tissues of "Chandler" walnuts when challenged with pathogen Xaj417 and concluded that SWEET-mediated sugar translocation from the host is not a trigger for walnut blight disease development. This may be directly related to the absence of type III secretion system-dependent transcription activator-like effectors (TALEs) in Xaj417, which suggests different strategies are employed by this pathogen to promote susceptibility to this major aboveground disease of walnuts.

14.
PLoS One ; 15(2): e0228051, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32012173

RESUMO

Achieving an optimal configuration of the diffuser is indispensable for high pump performances. In this work, a numerical study on diffuser configuration is conducted for a high pump performance using a computational fluid dynamics code, and the effects of the wrap angle and the relative position of the diffuser vane to the impeller on pump performances are included. The results indicate that the modified diffuser with a suitable wrap angle may improve the pump hydraulic efficiency and the head by approximately 4% and 8%, respectively, while a suitable position of the diffuser vane can enhance the pump head by more than 4%. Meanwhile, the pressure recovery coefficient and the local Euler head of the diffuser are adopted to evaluate the diffuser performance. For a high pump performance, the local Euler head of the diffuser has a peak value at the leading edge with the change rate of zero along the meridian streamline, meaning that no blade loading at the leading edge of the diffuser guarantees a better match between the impeller and the diffuser.

15.
Theor Appl Genet ; 133(4): 1227-1241, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31980837

RESUMO

KEY MESSAGE: We introgressed wheatgrass germplasm from the octoploid amphiploid Triticum aestivum× Lophopyrum elongatum into wheat by manipulating the wheat Ph1 gene and discovered and characterized 130 introgression lines harboring single or, in various combinations, complete and recombined L. elongatum chromosomes. Diploid wheatgrass Lophopyrum elongatum (genomes EE) possesses valuable traits for wheat genetics and breeding. We evaluated several strategies for introgression of this germplasm into wheat. To detect it, we developed and validated multiplexed sets of Sequenom MassARRAY single nucleotide polymorphism (SNP) markers, which differentiated disomic and monosomic L. elongatum chromosomes from wheat chromosomes. We identified 130 introgression lines (ILs), which harbored 108 complete and 89 recombined L. elongatum chromosomes. Of the latter, 59 chromosomes were recombined by one or more crossovers and 30 were involved in centromeric (Robertsonian) translocations or were telocentric. To identify wheat chromosomes substituted for or recombined with L. elongatum chromosomes, we genotyped the ILs with the wheat 90-K Infinium SNP array. We found that most of the wheat 90-K probes correctly detected their targets in the L. elongatum genome and showed that some wheat SNPs are ancient and had originated prior to the divergence of the wheat and L. elongatum lineages. Of the 130 ILs, 52% were homozygous for Ph1 deletion and thus are staged to be recombined further. We failed to detect in the L. elongatum genome the 4/5 reciprocal translocation that has been reported in Thinopyrum bessarabicum and several other Triticeae genomes.

16.
Molecules ; 25(3)2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31991642

RESUMO

Here, we describe a mild, catalyst-free and operationally-simple strategy for the direct fluoroalkylation of olefins driven by the photochemical activity of an electron donor-acceptor (EDA) complex between DMA and fluoroalkyl iodides. The significant advantages of this photochemical transformation are high efficiency, excellent functional group tolerance, and synthetic simplicity, thus providing a facile route for further application in pharmaceuticals and life sciences.

17.
Org Lett ; 22(3): 873-878, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31916771

RESUMO

New chalcone-based pyridinium salts have been successfully exploited, which could smoothly participate in the highly diastereoselective dearomatization with binucleophilic enaminones by taking advantage of their multiple reactive sites to construct bibridged benzoazepines in up to 89% yields. The key to the success was the skillful and unprecedented C-3 functionalization of the new pyridinium salts. This work not only provides a kind of novel pyridinium salt synthon but also achieves the first C-3 functionalization of pyridinium salts to construct complex and challenging bibridged benzoazepines with high synthetic efficiency.

18.
Org Lett ; 22(3): 1160-1163, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31965807

RESUMO

In this communication, an interesting carbonylation protocol for the preparation of α-branched enones has been established. Starting from readily available aryl iodides and allenes, with formic acid as the CO source and reductant, moderate to good yields of the desired enones were isolated. Although it is a carbonylation methodology, the use of a CO source can avoid the manipulation of CO gas directly. Notably, this procedure also presents the first example on carbonylative synthesis of α-branched enones.

19.
J Dig Dis ; 21(2): 104-111, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31922658

RESUMO

OBJECTIVE: To explore the effectiveness of gadobenate dimeglumine (Gd-BOPTA)-enhanced magnetic resonance imaging (MRI) in predicting portal hypertension and high-risk esophageal varices (EV) in patients with hepatitis B cirrhosis. METHODS: In total, 71 and 30 patients comprising the training and validation groups, respectively, were enrolled in the study. Univariate and multivariate analyses were performed to detect their risk of developing high-risk EV to generate a formula for scoring EV. The relationships between the relative enhancement ratio (RE) of Gd-BOPTA-enhanced MRI and portal vein pressure were explored. RESULTS: Platelet count, portal vein width and RE were identified as independent predictors of high-risk EV. Based on these parameters, the EV score model were calculated as: -6.483 + 15.612 × portal vein width + 2.251 × RE - 0.176 × platelet count. The area under the receiver operating characteristic curve was 0.903. At a cut-off value of ≤ -2.74, the negative predictive value was 94.00%, while the positive predictive value was as high as 93.80% when the cut-off was set at > 4.00. Gd-BOPTA-enhanced MRI was effective in predicting portal pressure. Its accuracy was confirmed with the validation set. CONCLUSIONS: Gd-BOPTA-enhanced MRI was successfully applied to evaluate high-risk EV and portal hypertension. These results represent an accurate, non-invasive model for detecting high-risk EV, based on which we propose a cost-effective algorithm for EV management, eliminating the need to perform an endoscopy in all patients with cirrhosis.

20.
FASEB J ; 34(2): 2609-2624, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31908017

RESUMO

Caveolae play crucial roles in intracellular membrane trafficking and mechanosensation. In this study, we report that synaptotagmin-11 (Syt11), a synaptotagmin isoform associated with Parkinson's disease and schizophrenia, regulates both caveolae-mediated endocytosis and the caveolar response to mechanical stimuli in astrocytes. Syt11-knockout (KO) accelerated caveolae-mediated endocytosis. Interestingly, the caveolar structures on the cell surface were markedly fewer in the absence of Syt11. Caveolar disassembly in response to hypoosmotic stimuli and astrocyte swelling were both impaired in Syt11-KO astrocytes. Live imaging revealed that Syt11 left caveolar structures before cavin1 during hypoosmotic stress and returned earlier than cavin1 after isoosmotic recovery. Chronic hypoosmotic stress led to proteasome-mediated Syt11 degradation. In addition, Syt11-KO increased the turnover of cavin1 and EH domain-containing protein 2 (EHD2), accompanied by compromised membrane integrity, suggesting a mechanoprotective role of Syt11. Direct interactions between Syt11 and cavin1 and EHD2, but not caveolin-1, are found. Altogether, we propose that Syt11 stabilizes caveolar structures on the cell surface of astrocytes and regulates caveolar functions under physiological and pathological conditions through cavin1 and EHD2.

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