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1.
Cell Mol Biol (Noisy-le-grand) ; 66(2): 125-129, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415938

RESUMO

The aim of this study was to investigate whether Jatrorrhizine hydrochloride (JAH) can attenuate oxidative damage of endothelial cells by regulating mitochondrial function and inflammatory response. It was found that JAH inhibited tert-butyl hydroperoxide (t-BHP)-induced oxidative damage in mouse brain endothelial cells (MBECs) by increasing cell viability and inhibiting cell apoptosis. Moreover, JAH significantly inhibited the production of reactive oxygen species (ROS) and lipid peroxidation. It enhanced mitochondrial membrane potential (MMP) and maintained ATP synthesis. In addition, JAH regulated the expressions of inflammatory cytokines and increased the activation of endothelial nitric oxide synthase (eNOS). The protective effect of JAH was related to the protein expression of peroxisome proliferator-activated receptor-γ (PPAR-γ) gene. In conclusion, these results suggest that JAH may have therapeutic potential for ischemic stroke associated with endothelial dysfunction through its antioxidant and anti-inflammatory properties.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32449029

RESUMO

PURPOSE: Using the Reflux Symptom Index (RSI), this nationwide study aimed to investigate the incidence, diagnostic status, risk factors, and common symptoms of adult laryngopharyngeal reflux disease (LPRD) at otorhinolaryngology-head and neck surgery (OHNS) clinics in China. METHODS: This multicenter cross-sectional survey began at the different institutions ranged from July to October 2017, and the duration was 12 months. A total of 90,440 eligible patients were finally enrolled from 72 medical institutions in China. All these patients completed the questionnaire based on RSI. In this study, LPRD was defined as RSI > 13. RESULTS: There were 9182 with LPRD among the 90,440 eligible participants (10.15%). However, only 1294 had a history of LPRD diagnosis among those with LPRD (14.09%). There were regional differences in the frequency of LPRD (P < 0.001). The proportions of patients with LPRD in males (vs. females), middle- and old-aged patients (vs. young), with current smoking history (vs. no smoking), and current drinking history (vs. no drinking) were significantly higher (all P < 0.001). Middle and old age, current smoking, and drinking history were independent predictors of LPRD (all P < 0.001, OR 1.240, 1.261, and 1.481, respectively). "Sensations of something stuck in throat or a lump in throat", "clearing throat", and "excess throat mucus or postnasal drip" were the most frequent clinical symptoms in patients with LPRD. CONCLUSIONS: LPRD has a high incidence at the OHNS clinics in China. However, the diagnostic status of this disease is not optimistic. Older age, smoking, and drinking history were risk factors for LPRD.

3.
Stem Cell Res Ther ; 11(1): 157, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32299508

RESUMO

BACKGROUND: The development of somatic reprogramming, especially purely chemical reprogramming, has significantly advanced biological research. And chemical-induced extraembryonic endoderm-like (ciXEN) cells have been confirmed to be an indispensable intermediate stage of chemical reprogramming. They resemble extraembryonic endoderm (XEN) cells in terms of transcriptome, reprogramming potential, and developmental ability in vivo. However, the other characteristics of ciXEN cells and the effects of chemicals and bFGF on the in vitro culture of ciXEN cells have not been systematically reported. METHODS: Chemicals and bFGF in combination with Matrigel were used to induce the generation of ciXEN cells derived from mouse embryonic fibroblasts (MEFs). RNA sequencing was utilised to examine the transcriptome of ciXEN cells, and PCR/qPCR assays were performed to evaluate the mRNA levels of the genes involved in this study. Hepatic functions were investigated by periodic acid-Schiff staining and indocyanine green assay. Lactate production, ATP detection, and extracellular metabolic flux analysis were used to analyse the energy metabolism of ciXEN cells. RESULTS: ciXEN cells expressed XEN-related genes, exhibited high proliferative capacity, had the ability to differentiate into visceral endoderm in vitro, and possessed the plasticity allowing for their differentiation into induced hepatocytes (iHeps). Additionally, the upregulated biological processes of ciXEN cells compared to those in MEFs focused on metabolism, but their energy production was independent of glycolysis. Furthermore, without the cocktail of chemicals and bFGF, which are indispensable for the generation of ciXEN cells, induced XEN (iXEN) cells remained the expression of XEN markers, the high proliferative capacity, and the plasticity to differentiate into iHeps in vitro. CONCLUSIONS: ciXEN cells had high plasticity, and energy metabolism was reconstructed during chemical reprogramming, but it did not change from aerobic oxidation to glycolysis. And the cocktail of chemicals and bFGF were non-essential for the in vitro culture of ciXEN cells.

4.
Microb Pathog ; 145: 104213, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32333954

RESUMO

Current problem of antibiotic resistance and the high incidence of bacterial diseases has brought huge losses to the yak breeding industry in Tibet. Therefore, the purpose of this study was to isolate Lactobacillus with safety and beneficial probiotic potential for the prophylaxis of intestinal diseases in yaks. After 16S rDNA sequence, four strains i.e. Lactobacillus sakei (named L4), Enterococcus hirae (named E5), Pediococcus acidilactici (named P7), Weissella confusa (named W8) were isolated from feces of yaks. The results of tolerance to acid, bile salt, enzyme and temperature showed that P7 was highly tolerant to acid, bile salt and digestive enzyme, while E5 was more resistant to temperature. The antibacterial assay showed L4 had a strong inhibitory effect against Staphylococcus aureus (BNCC186335), and E5, P7, W8 had effective antibacterial ability against Escherichia coli (C83902). In addition, L4, E5, P7 and W8 mainly produced organic acids and bacteriocin production to inhibit common intestinal pathogens. The results of antibiotic susceptibility assay indicated that L4, E5, P7 and W8 were highly sensitive to most clinically used antibiotics and didn't contain the VanA and VanB genes on the basis of PCR amplification, and L4, E5, P7 and W8 didn't exhibit hemolytic activity. The animal toxicity experiment results showed that no obvious pathological change was found in intestinal tissue sections, and L4, E5 and W8 strains also promoted the growth performance of mice, consequently, the L4, E5, P7 and W8 had no toxic effect on mice. In conclusion, lactobacillus isolated from feces of yaks not only have potential probiotics and strong antibacterial ability in vitro, but also are safe. Therefore, they have the potential to reduce the occurrence of bacterial diseases as new feed additives.

5.
Theranostics ; 10(10): 4544-4556, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32292514

RESUMO

Liquid biopsy is a convenient, fast, non-invasive and reproducible sampling method that can dynamically reflect the changes in tumor gene expression profile, and provide a robust basis for individualized therapy and early diagnosis of cancer. Circulating tumor DNA (ctDNA) and circulating tumor cells (CTCs) are the currently approved diagnostic biomarkers for screening cancer patients. In addition, tumor-derived extracellular vesicles (tdEVs), circulating tumor-derived proteins, circulating tumor RNA (ctRNA) and tumor-bearing platelets (TEPs) are other components of liquid biopsies with diagnostic potential. In this review, we have discussed the clinical applications of these biomarkers, and the factors that limit their implementation in routine clinical practice. In addition, the most recent developments in the isolation and analysis of circulating tumor biomarkers have been summarized, and the potential of non-blood liquid biopsies in tumor diagnostics has also been discussed.

6.
iScience ; 23(3): 100968, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32199293

RESUMO

R-loops, three-stranded DNA-DNA:RNA hybrid structures, are best known for their deleterious effects on genome stability. The regulatory factors of this fundamental genetic structure remain unclear. Here, we reveal an epigenetic factor that controls R-loop stability. METTL8, a member of the methyltransferase-like protein family that methylates 3-methylcytidine (m3C), is a key factor in the R-loop regulating methyltransferase complex. Biochemical studies show that METTL8 forms a large SUMOylated nuclear RNA-binding protein complex (∼0.8 mega daltons) that contains well-reported R-loop related factors. Genetic ablation of METTL8 results in an overall reduction of R-loops in cells. Interaction assays indicated METTL8 binds to RNAs and is responsible for R-loop stability on selected gene regions. Our results demonstrate that the SUMOylated METTL8 promotes tumorigenesis by affecting genetic organization primarily in, or in close proximity to, the nucleolus and impacts the formation of regulatory R-loops through its methyltransferase activity on m3C.

7.
Diagn Pathol ; 15(1): 16, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32050977

RESUMO

BACKGROUND: Papillary thyroid carcinoma (PTC) is an indolent tumor that is exploding with increasing thyroid nodules (TN). Environmental carcinogens, lifestyle changes increased the incidence of thyroid carcinoma. With the development of B-ultrasound imaging, more and more thyroid cancer has been found. There has been a debate about whether thyroid cancer is overtreated. METHODS: The expression of T cell subsets and plasma cytokines in 191 patients, including 79 patients with PTC (PTC group), 58 patients with thyroid nodules (TN group) and 54 healthy individuals (HP group) were analyzed by flow cytometry. RESULTS: High levels of natural killer cells (NK) were detected in PTC and TN groups than in HP group. High activities of CD8+HLA-DR+ and CD8+CD38+ showed a gradual upward trend from HP group to PTC group. The rise in the levels of TNF-α in PTC patients' was evident when compared with HP group. CD8+CD38+ showed a significant correlation with lymph node metastasis. CD8+CD38+ co-expression was higher in Nx stage than N0 stage, while the proportion of IL-10 was dramatically decreased in the Nx stage. CONCLUSIONS: These results indicated that CD8+CD38+ might act as a biomarker of PTC lymph node metastasis. The combination of CD8+HLA-DR+, CD8+CD38+ and TNF-α can be used as useful biomarkers for the early-warning indicator of PTC.

8.
J Ethnopharmacol ; 253: 112661, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32058006

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Essential hypertension is a prevalence chronic cardiovascular disease, which is treated by traditional Chinese medicine (TCM) in China. Metabolomics approach has achieved more attention in pharmacology studies of natural products. Tianma Gouteng Decoction (TGD) is effective for the therapeutic of hypertension in China. We aimed to investigate antihypertension effect of TGD on spontaneous hypertension rat (SHR) with live-Yang hyperactivity hypertension (Gan Yang Shang Kang, GYSK) and explore the mechanism by metabolomics method. MATERIALS AND METHODS: After establishing the GYSK-SHR model by giving aconite decoction, rats were randomly divided into four groups including model group, TGD qd group (66.88 mg/kg, once a day), TGD bid group (33.44 mg/kg, twice a day), TGD tid group (22.29 mg/kg, three times a day). Blood pressure (BP) and indexes of renin-angiotensin-aldosterone system (RAAS system) were measured. Metabolic profiling of rat plasma samples was performed by UPLC-Q-TOF/MS, which was analyzed with principal component analysis (PCA) and partial least-squares-discriminate analysis (PLS-DA) to explore the relationship between metabolic pathways and hypertension. RESULTS: To better explain the role of TGD on hypertension, we detected three different frequencies of TGD treatment with equal dosage. TGD reduced the BP in GYSH-SHR model and regulated the serum levels of NE, Ang II, ET, 5-HT, CRP, RENIN and ALD especially at TGD bid group. By UPLC-Q-TOF/MS analysis, we found 47 potential biomarkers in GYSK-SHR rats from the plasma metabolites, among which 15 biomarkers were regulated by TGD. Consisted with the antihypertension activity, TGD bid group showed the significantly moderating effect on the regulating biomarkers. CONCLUSIONS: TGD exhibited the antihypertensive activity at the frequency of administration twice a day, which had the association with RAAS system and mediated 15 biomarkers by regulating metabolisms of glycerol phospholipid, sphingomyelin, energy and amino acid.

9.
J Voice ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32081507

RESUMO

BACKGROUND: Few satisfactory animal models of laryngopharyngeal reflux (LPR) is available. Interleukin-8 (IL-8) and vascular endothelial growth factor (VEGF) may be associated with the pathogenesis of LPR injuries and laryngeal carcinomas. OBJECTIVES: To establish an animal model of LPR and to explore the related pathological changes and cytokine expression in the vocal cord tissue. METHODS: Twenty rabbits were divided into experimental and control groups. Dilatation of the upper and lower esophageal sphincter were carried out in the experimental group. The pH of the pharynx, pathological, and ultrastructural changes of the laryngeal tissue, and expression of IL-8 and VEGF were compared between the experimental group and controls. RESULTS: pH monitoring results and the dilated intercellular space of the vocal cord mucosa showed that the experimental group developed laryngopharyngeal reflux. There were significant differences in the immunohistochemical staining scores of both IL-8 (P = 0.015) and VEGF (P = 0.007) between the experimental and control groups in the vocal cord tissue. CONCLUSIONS: We successfully established a model of LPR, showing histopathological and ultrastructural changes consistent with the disease. The expression of IL-8 and VEGF may increase during the pathogenesis of LPR.

10.
Ther Apher Dial ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31916667

RESUMO

PURPOSE: To evaluate the safety and efficacy of tunneled dialysis catheter exchange through fibrin sheath crevice vs in-situ catheter exchange in hemodialysis patients with fibrin-sheath-related catheter dysfunction. METHODS: Patients with fibrin-sheath-related catheter dysfunction underwent tunneled dialysis catheter exchange in our center between 2012 January to 2017 December were retrospectively screened. The included patients were divided into the sheath-crevice group (catheter was exchanged through fibrin sheath crevice) and the in-situ group (catheter was exchanged in-situ). The blood volume, Kt/V values, and complications were accessed as outcomes. RESULTS: Of the 44 included patients, 25 underwent in-situ catheter exchange and 19 underwent catheter exchange through fibrin sheath crevice. The stabilized maximal blood flow during the first hemodialysis after the catheter replacement reached 250 mL/min in all of the included patients. After 3 months, the stabilized maximal blood flow of the in-situ group and the sheath-crevice group were 245.3 ± 9.0 mL/min and 244.8 ± 10.05 mL/min (P = 0.963), respectively. However, after 6 months, the stabilized maximal blood flow during hemodialysis (P = 0.048) and the Kt/V value (P < 0.001) of the patients in the sheath-crevice group were significantly higher than the in-situ group. No severe complication related to the catheter exchange surgery was observed in neither group. CONCLUSION: For patients with tunneled dialysis catheter dysfunction caused by fibrin sheath, catheter exchange through fibrin sheath crevice most likely is an safe and effective alternative strategy of the in-situ catheter exchange. This article is protected by copyright. All rights reserved.

11.
J Agric Food Chem ; 68(6): 1536-1545, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31961689

RESUMO

In this work, an electrical-driven release and migration glyphosate (EDRMG) was fabricated using a nanocomposite made up of attapulgite (ATP), glyphosate (Gly), and calcium alginate (CA). Therein, ATP-CA acted as a nanonetwork-structured carrier to efficiently load plenty of Gly to form porous ATP-Gly-CA hydrogel spheres (actually EDRMG-0.5) via a cross-linking reaction. The pores in EDRMG-0.5 hydrogel spheres were enlarged under an electric field because of the Coulomb force of the anionic CA polymer, and the release of negatively charged Gly from the spheres could be driven by the electric field force. Thus, EDRMG-0.5 exhibited a great electroresponsively controlled-release property, which was confirmed by a pot experiment. Importantly, the EDRMG-0.5 hydrogel spheres had fine biocompatibility on fish and mice, displaying good biosafety. This work provides a low cost and promising approach to control Gly release, deliver Gly precisely, and improve utilization efficiency, which might have a high application value.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Glicina/análogos & derivados , Herbicidas/química , Nanogéis/química , Alginatos/química , Animais , Portadores de Fármacos/química , Composição de Medicamentos , Sistemas de Liberação de Medicamentos/economia , Sistemas de Liberação de Medicamentos/instrumentação , Eletricidade , Peixes , Glicina/química , Hidrogéis/química , Compostos de Magnésio/química , Camundongos , Compostos de Silício/química
12.
Anaerobe ; 61: 102115, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31711887

RESUMO

Yak (Bos grunniens), a ruminant, has a complex gastrointestinal microbial ecosystem, which is essential for host nutrition and health. However, not much is known about gut microbial communities of yak. This study was conducted to characterize the gut microbial diversity and composition of small intestinal and cecal contents of yaks through high-throughput sequencing targeting V3-V4 hypervariable region of 16S rRNA gene. A total of 916,934 high-quality sequences were obtained and 224 core operational taxonomic units (OTUs) shared all samples. The result showed that the microbial community in the small intestine was different from cecum sample. In all samples, the majority of bacterial phyla were Firmicutes, Bacteroidetes and Proteobacteria. A large proportion of anaerobes in the families Peptostreptococcaceae, Prevotellaceae, Flavobacteriaceae, Lachnospiraceae, and Succinivibrionaceae were present in the various intestinal segments. The relative abundance of Ruminococcaceae, Bacteroidaceae and Muribaculaceae were significantly higher in cecum than in other segments of intestines. At the genus level, Bacteroides was the most predominant genus in cecum. The results indicated that yak have abundant and diverse gut microbial community. In conclusion, this study characterized the profiles of microbial communities across intestinal segments and provide better insight into microbial population structure and diversity of yak.

13.
J Chromatogr A ; 1611: 460576, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31606158

RESUMO

Countercurrent chromatography (or counter-current chromatography, CCC) is a unique support-free liquid-liquid partition chromatography. Since it was invented by Y. Ito in 1960s, CCC has been widely accepted and applied as popular separation and purification technique for natural and synthetic complex. However, up to date there is little study to address on hydrophobic and hydrophilic interactions in CCC process, although hydrophobic interaction chromatography (HIC) and hydrophilic interaction chromatography (or hydrophilic interaction liquid chromatography, HILIC) as solid-support chromatographic techniques are widely applied at different stages of downstream processing. In fact, hydrophobic and hydrophilic interactions might be more popular in CCC separation than that in the liquid chromatography. For example, adding small solvents or additives in two-phase solvent systems may change significantly hydrophobic or hydrophilic interactions between solvents and solutes. Normally, CCC separation employs a light and hydrophobic organic phase as the stationary phase, and a heavy and hydrophilic aqueous phase as the mobile phase. Hydrophobic interactions between the solvent system and solutes (targets) will increase the partition coefficients (K values) of solutes and lengthen retention time, while hydrophilic interactions will reduce the K values and separation time. In this work, we aim to provide a general insight on the hydrophobic and hydrophilic interactions in CCC separation. We also highlight the current advances in utilizing the hydrophobic and hydrophilic interactions for K-targeted CCC separation and purification.

14.
Acta Trop ; 201: 105212, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31600521

RESUMO

Fasciolosis is one of the biggest threats to livestock and human population. For this purpose, the seroprevalence of Fasciola hepatica was investigated in yaks and sheep living on the Qinghai-Tibet plateau, China by piloting commercial ELISA kits. A total of 3276 yaks and 1092 sheep were incorporated in this study. The prevalence of the parasite in yaks and sheep was 38.3% and 26.4%, respectively. The serological results revealed a relatively high prevalence of F. hepatica infection in yaks and sheep, respectively. The present study may greatly contribute to the prevention of this parasitic zoonosis and great importance should be given to the potential threat caused by F. hepatica in this special plateau.


Assuntos
Doenças dos Bovinos/parasitologia , Fasciola hepatica/isolamento & purificação , Fasciolíase/epidemiologia , Gado/parasitologia , Doenças dos Ovinos/parasitologia , Animais , Bovinos/parasitologia , Doenças dos Bovinos/epidemiologia , China/epidemiologia , Humanos , Prevalência , Estudos Soroepidemiológicos , Ovinos/parasitologia , Doenças dos Ovinos/epidemiologia , Inquéritos e Questionários , Tibet/epidemiologia , Zoonoses/epidemiologia
15.
Ying Yong Sheng Tai Xue Bao ; 30(12): 4003-4011, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31840444

RESUMO

Nitrogen deposition will affect the morphology of fine roots and its absorption of nutrien-ts, resulting in changes nutrient cycling in terrestrial ecosystems. In order to understand the effects of nitrogen deposition on fine root morphological traits of Castanopsis fabri and C. carlesii, two ectomycorrhizas tree species, we carried out in situ experiment using the root bags method in an evergreen broadleaved forest in the subtropical zone. The results showed that the plastic responses of specific root length and specific root surface area of low-order roots (first to third order) to nitrogen addition was higher than that of high-order roots (fourth order). The plastic responses of root tissue density to nitrogen addition increased from the first-order to the fourth-order, while the average root diameter of each order had no significant plastic responses to nitrogen addition. There was a certain synergistic change between the plastic response of specific root length and specific surface area in the low order fine root and the plastic response of tissue density in the high order fine root. The specific root length, specific root surface area and root tissue density of the two species showed opposite plastic responses to nitrogen addition, indicating that different ectomycorrhizal tree species had different nutrient foraging strategies. C. fabri adopted rapid absorption strategy by increasing specific root length, specific root surface area, and proliferation rate of fine root length, while C. carlesii adopted a relatively conservative resource absorption strategy by increasing tissue density of fine roots.


Assuntos
Ecossistema , Nitrogênio , Florestas , Raízes de Plantas , Plásticos , Árvores
16.
J Clin Lab Anal ; : e23131, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31777102

RESUMO

BACKGROUND: Emerging reports demonstrated that PIWI-interacting RNAs (piRNAs) played an indispensable role in tumorigenesis. However, it still remains elusive whether piR-1245 in gastric juice specific in stomach could be employed as a biomarker for gastric cancer (GC). The present work is aiming at exploring the possibility of piR-1245 in gastric juice as a potential marker to judge for diagnosis and prognosis of gastric cancer. METHODS: Gastric juice was collected from 66 GC patients and 66 healthy individuals. Quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) was employed to measure the levels of piR-1245 expression. Then, the pattern of piR-1245 expression in gastric juice was determined between GC patients and healthy individuals. A receiver operating characteristic (ROC) curve was constructed for distinguishing GC from healthy individuals. RESULTS: Gastric juice piR-1245 levels in GC were higher than those of controls (P < .0001). The value of area under ROC (AUC) was 0.885 (sensitivity, 90.9%; specificity, 74.2%; 95% confidence interval, 0.8286 to 0.9414). High gastric juice piR-1245 expression was signally correlated with tumor size (P = .013) and TNM stage (P = .001). GC patients with high piR-1245 expression in gastric juice exerted a poorer overall survival (OS) (P = .0152) and progression-free survival (PFS) (P = .013). COX regression analysis verified that gastric juice piR-1245 expression was an independent prognostic risk variable for OS (P < .05). CONCLUSIONS: The current study suggested that piR-1245 in gastric juice had the potential to be a useful biomarker for GC detection and prognosis prediction.

17.
Quant Imaging Med Surg ; 9(10): 1697-1713, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31728313

RESUMO

Background: Chemical exchange saturation transfer (CEST) MRI requires the acquisition of multiple saturation-weighted images and can last several minutes. Misalignments among these images, which are often due to the inevitable motion of the subject, will corrupt CEST contrast maps and result in large quantification errors. Therefore, the registration of the CEST series is critical. However, registration is challenging since common intensity-based registration algorithms may fail to differentiate CEST signals from motion artifacts. Herein, we studied how different patterns of motion affect CEST quantification and proposed a cascaded two-step registration scheme by utilizing features extracted from the entire Z-spectral image series instead of direct registration to a single image. Methods: The proposed approach is conducted in two stages: during the first coarse registration, the Z-spectral image series is decomposed by robust principal component analysis (RPCA) to separate CEST contrast from motion. The recomposed image series using only the low-rank component, which contains minimized motion, are averaged to generate a reference for the alignment of the image series. To further remove residual misalignments, the coarse registration is followed by a refinement stage, which uses PCA iteratively to generate motionless synthetic reference series with the first few principal components (PCs) that correspond to CEST contrast. In the end, the quality check is performed to exclude the images with unsuccessful registration. Results: The proposed registration scheme (RPCA + PCA_R) was assessed by both phantom experiments and in vivo data of tumor-bearing mouse brain, with simulated random rigid motion in different patterns applied to the acquired static Z-spectral image series. For comparison, previous correction schemes using an explicit image [either S0 or Ssat(∆ω)] as registration reference were also performed, named as S0_R and Ssat_R respectively. To illustrate the advantage of combination of RPCA and PCA, registration was also exploited using either only the RPCA-based method (RPCA_R) or only the PCA-based one (PCA_R). Compared with the above four methods, RPCA + PCA_R allowed for more accurate correction of the corrupted Z-spectral images, exhibiting smaller MTRasym(∆ω) error maps and lower residual Z-spectra referring to the static data. Among all the five correction methods, the corrected Z-spectral image series by RPCA + PCA_R and the resulting MTRasym(∆ω) maps achieved the highest correlation coefficients (CC) with respect to the static ones. Conclusions: The registration scheme of RPCA + PCA_R provides robust motion correction between two specific Z-spectral images and among an entire image series, through extraction of the static component from the entire Z-spectra set and inclusion of a PCA-based refinement step. Therefore, this method can help improve CEST acquisition and quantification.

18.
Quant Imaging Med Surg ; 9(10): 1714-1730, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31728314

RESUMO

Background: Chemical exchange saturation transfer (CEST) MRI is a promising approach for detecting biochemical alterations in cancers and neurological diseases, but the quantification can be challenging. Among numerous quantification methods, Lorentzian difference (LD) is relatively simple and widely used, which employs Lorentzian line-shape as a reference to describe the direct saturation (DS) of water and takes account of difference against experimental CEST spectra data. However, LD often overestimates CEST and nuclear overhauser enhancement (NOE) effects. Specifically, for fast-exchanging CEST species require higher saturation power (B1_sat) or in the presence of strong magnetization transfer (MT) contrast, Z-spectrum appears more like a Gaussian line-shape rather than a Lorentzian line-shape. Methods: To improve the conventional LD analysis, the present study developed and validated a novel fitting algorithm through a linear combination of Gaussian and Lorentzian function as the reference spectra, namely, Voxel-wise Optimization of Pseudo Voigt Profile (VOPVP). The experimental Z-spectra were pre-fitted with Gaussian and Lorentzian method independently, in order to determine Lorentzian proportionality coefficient (a). To further compensate for the line-shape changes under different B1_sat's, a B1-dependent adjustment was applied to the experimental Z-spectra (Z_exp) according to the prior knowledge learned from 5-pool Bloch equation-based simulations at a range of B1_sat's. Then, the obtained Z-spectra (Z_B1adj) was fitted by the previously defined VOPVP function. Considering the asymmetric component of MT, the positive- and negative-side of Z-spectra were fitted separately, while the middle part (-0.6 to 0.6 ppm, consisted primarily of DS) was fitted using Lorentzian function. Finally, the difference between Z_VOPVP and Z_exp was defined as the CEST and NOE contrast. To validate our VOPVP method, an extensive simulation of CEST Z-spectra was performed using 5-pool model and 6-pool model with greater MT component. Results: In comparison with LD approach, VOPVP exhibited lower sum of squares due to error (SSE) and higher goodness of fit (R-square) for the experimental Z-spectra at all B1_sat. Moreover, the results indicated that VOPVP fitting improved the overestimated contributions from amide proton transfer (APT) and NOE through LD at all B1_sat. Despite that the relationship for B1-dependent adjustment was pre-determined using a single 5-pool model, the VOPVP fittings obtained accurate quantification for multiple 6-pool models with a range of T1w's and T2w's. The robustness of VOPVP fitting was also proved by simulations using 3T parameters. Furthermore, we assessed VOPVP in vivo in a glioblastoma-bearing mouse. Compared to LD maps, VOPVP quantification maps displayed higher contrast-to-noise ratio between tumor and normal contralateral tissue for APT, glutamate and nuclear overhauser effect (NOE), when B1_sat >1 µT. Conclusions: As an improvement of LD method, VOPVP fitting can serve as a simple, robust and more accurate approach for quantifying CEST and NOE contrast.

19.
Diagn Pathol ; 14(1): 128, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711519

RESUMO

BACKGROUND: Large B cell lymphoma (DLBCL) is the most common type of non-Hodgkin's lymphoma among adults. In some cases, DLBCL may seem similar to carcinoma cells, presenting a round, oval, or polygonal shape and clear nuclei. We found that the expression of P63 accounted for a considerable proportion of DLBCL cases. Under the circumstances, P63 expression may lead to a misdiagnosis, especially with a small biopsy. We aim to investigate the expression status and prognostic significance of P63 in a cohort of Chinese DLBCL patients. METHODS: P63, ΔNP63(P40), P53 and Ki67 were detected by immunohistochemistry (IHC). A ROC curve was adopted to find the best cut-off value for positive P63/P53 expression and high Ki67 expression. We defined P53 as positive when ≥50% of the tumor cells showed staining. The relationship between P63 and P53/Ki67 expression was examined. Time-to-event endpoints were estimated according to the Kaplan-Meier method. Moreover, multivariate analyses were conducted to evaluate the prognostic factors in DLBCL. RESULTS: Out of all the 159 DLBCL cases, 76 (47.8%) expressed P63 in the nuclei, while 41 (25.8%) were determined to have high expression by using a ROC cut-off value "≥6". Examination of the different P63 isoforms revealed that the ΔNP63(P40) was unclearly and weakly expressed in only 3 cases, showing a fuzzy yellow cytoplasm. P63 expression was not correlated with subtype (GCB or non-GCB) or P53 but was correlated with a high proliferative index (Ki67). Kaplan-Meier analyses revealed that P63 expression was correlated with overall survival, and P63 positive cases showed poor survival outcomes (P<0.05) in our cohort. CONCLUSIONS: ΔNP63(P40) is a useful marker in the differential diagnosis of poorly differentiated squamous cell carcinoma versus DLBCL in small needle biopsy. P63 may be involved in DLBCL tumor progression, and it is an unfavorable prognostic marker in DLBCL. A subgroup of P63 and P53 coexpression DLBCL patients with an extremely poor prognosis should be noted.

20.
Environ Sci Pollut Res Int ; 26(36): 36322-36332, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31713825

RESUMO

The widespread use of thiram has raised concerns for health and its toxic effects, but the underlying toxicity mechanism on platelets and bones is poorly defined. Here, we found a significant increase in the number of platelets in chickens with the thiram intake, due to the increased expression of thrombopoietin mRNA in the dysfunction liver. Furthermore, the decreased vascular distribution and cell death of chondrocytes in the tibial growth plates (TGPs) were observed, resulting in bone growth inhibition, which is associated with the abnormal activation of platelets leading to the extraordinary decrease of vascular endothelial growth factor A (VEGFA) and angiopoietin-1 protein were released and their corresponding receptors VEGFR2 and Tie-2 expressions were also reduced in the TGPs. Taken together, these findings revealed that thiram has an adverse effect on bones and platelets, which may have a high risk of thrombosis and osteoarthritis.


Assuntos
Galinhas/sangue , Galinhas/crescimento & desenvolvimento , Lâmina de Crescimento/efeitos dos fármacos , Praguicidas/toxicidade , Tiram/toxicidade , Proteínas Angiogênicas/metabolismo , Animais , Lâmina de Crescimento/irrigação sanguínea , Lâmina de Crescimento/metabolismo , Lâmina de Crescimento/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Contagem de Plaquetas , Trombopoetina/metabolismo , Tíbia/efeitos dos fármacos , Tíbia/crescimento & desenvolvimento
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