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1.
Zhongguo Gu Shang ; 33(4): 371-5, 2020 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-32351094

RESUMO

OBJECTIVE: To evaluate the clinical effect of bridge combined internal fixation system in the treatment of periprosthesis fracture of femur after hip replacement. METHODS: From October 2016 to June 2018, 5 patients of periprosthesis fractures of femur classified type B1 and type C in Vancouver were treated by open reduction and bridging combined with internal fixation, including 2 males and 3 females, with ages of 68, 70, 74, 75, 79 years;type B1 fractures in 4 and type C fractures in 1. Causes of injury:1 case of traffic injury, 4 cases of fall. After the operation, the patients were followed up for complications and fracture healing time by clinical and imaging examination, and Parker activity score was performed. RESULTS: The wounds of 5 patients healed without infection. One case of DVT was confirmed by venography. Five patients were followed up, and the durations were 2, 8, 9, 10, 15 months. One patient died of myocardial infarction 2 months after operation. The average healing time was 12.5 weeks. No loss of reduction or failure of internal fixation was found. Two patients could walk without protection and 1 patient needed to rely on single crutch. One case of periprosthetic fracture had to walk with a single crutch before operation and move indoors with two crutches after operation. The average Parker activity score was 51.8% before operation. CONCLUSION: The bridge combined internal fixation system can be used to fix the fracture after hip replacement with stable femoral prosthesis.

2.
Org Biomol Chem ; 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32367108

RESUMO

Hydroboration of 1,3-dienes can provide useful intermediates with multiple functionalities. However, achieving high regioselectivity is still a challenge. Recent experimental research studies indicate that this challenge could be overcome by the ligand effect. We made DFT calculations to elucidate the origin of ligand controlled regioselectivity in cobalt catalyzed hydroboration of 2-substituted 1,3-diene. The following conclusions have been reached: when using PHOX ((2-oxazolinyl)-phenyldiphenylphosphine) as the ligand, the favorable 1,4-selective oxidative hydrogen migration pathway was suggested to start with the rate-determining step of 1,4-selective oxidative hydrogen migration followed by reductive boryl migration. The unique 1,4-selectivity is proposed to be a result of the less steric hindrance between the substrate and the ligand PHOX. When dppp (1,3-bis-(diphenylphosphino)propane) is used as the ligand, the favorable pathway is proposed to be a 1,2-selective oxidative boryl migration pathway which involves 1,2-selective oxidative boryl migration and reductive hydrogen migration. Interestingly, another smaller-bite angle bisphosphine ligand dppe (1,2-bis(diphenylphosphino)ethane) favors the 1,4-selective oxidative boryl migration pathway. DFT calculations revealed that the preferred oxidative boryl migration pathway with both dppp and dppe is attributed to their electron-rich properties which accelerate the oxidative boryl migration step. The larger bite angle of dppp than that of dppe leads to bulkier steric hindrance and promotes 1,2-selective reductive hydrogen migration. On the other hand, for dppe with a smaller bite angle, the steric effect in the reductive hydrogen migration step is not dominant and 1,4-selective reductive hydrogen migration is favored. It is expected that the analysis of the ligand effect on the regioselectivity would enable further catalyst design.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32287018

RESUMO

Analysis and design of steady states representing cell types, such as cell death or unregulated growth, are of significant interest in modeling genetic regulatory networks. In this article, the steady-state design of large-dimensional Boolean networks (BNs) is studied via model reduction and pinning control. Compared with existing literature, the pinning control design in this article is based on the original node's connection, but not on the state-transition matrix of BNs. Hence, the computational complexity is dramatically reduced in this article from O(2n x 2n) to O(2 x 2r), where n is the number of nodes in the large-dimensional BN and r< n is the largest number of in-neighbors of the reduced BN. Finally, the proposed method is well demonstrated by a T-LGL survival signaling network with 18 nodes and a model of survival signaling in large granular lymphocyte leukemia with 29 nodes. Just as shown in the simulations, the model reduction method reduces 99.98% redundant states for the network with 18 nodes, and 99.99% redundant states for the network with 29 nodes.

4.
Head Neck ; 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32314842

RESUMO

BACKGROUND: This study is to explore the role of curcumin and GLUT-1 antisense oligodeoxynucleotides (AS-ODN) on autophagy modulation-initiated radiosensitivity. METHODS: BALB/c mice were employed to establish xenograft model using Tu212 cell. The expression of autophagy- and apoptosis-related proteins was determined by WB. Autophagosome was observed under transmission electron microscope. Apoptosis of tumor tissue were detected by TUNEL staining. RESULTS: Combinations of curcumin and GLUT-1 AS-ODN with 10 Gy inhibited the tumor growth by inducing apoptosis of laryngeal cancer cells followed with the enhancement of autophagy. 3-MA also had a promotion effect on irradiation-mediated growth inhibition possibly by depressing PI3K and on curcumin/GLUT-1 AS-ODN-mediated growth inhibition potentially by regulating autophagic events. Of note, a de-escalation of radiotherapy dose (5 Gy) along with curcumin, GLUT-1 AS-ODN or 3-MA produced a stronger effect than high dosage of radiotherapy (10 Gy) alone. CONCLUSIONS: Curcumin and GLUT-1 AS-ODN improve the radiosensitivity of laryngeal carcinoma through regulating autophagy and inducing apoptosis.

5.
Ann Vasc Surg ; 2020 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-32234575

RESUMO

BACKGROUND: The aim of this study is to explore the effects of statin therapy with the abdominal aortic aneurysm (AAA) growth rate and mortality. METHODS: Databases of PubMed, EMBASE, Ovid, Wanfang, and China National Knowledge Infrastructure were investigated for eligible literatures from their establishments to May 2019. Included studies were selected according to precise eligibility criteria. Statistical analysis was performed by RevMan 5.3 software. RESULTS: Fourteen studies with a total of 38,749 patients of whom 15,993 underwent statins treatment and 22,756 underwent placebo or conventional therapy were eligible for meta-analysis. The pooled results indicated that the statin use was related to a significantly lower AAA growth rate (mean difference = -1.5 mm/year, 95% confidence interval [CI] = -1.99 to -1.02, P < 0.00001). In addition, statins can significantly reduce the short-term mortality (in-hospital or 30 days) (odds ratio = 0.63, 95% CI = 0.56-0.7, P < 0.00001) and long-term mortality (1 year after surgery) after AAA repair (odds ratio = 0.67, 95% CI = 0.61-0.74, P < 0.00001). CONCLUSIONS: This meta-analysis revealed that statin therapy can reduce the risks of AAA growth rates and mortality. However, due to its significant heterogeneity in the included studies, the consequence should be understood with caution.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32154936

RESUMO

BACKGROUND AND AIM: The presence and severity of upper gastrointestinal mucosal lesions have not been evaluated using esophagogastroduodenoscopy (EGD) in patients receiving ticagrelor plus aspirin or alone after myocardial revascularization. We assessed upper gastrointestinal mucosal injury and the use of proton pump inhibitors (PPIs) in patients receiving 1 year of antiplatelet therapy after coronary artery bypass grafting (CABG). METHODS: In this single-center prospective substudy of a randomized trial, 231 patients completing 1-year antiplatelet therapy (ticagrelor 90 mg twice daily plus aspirin 100 mg once daily, ticagrelor 90 mg twice daily, or aspirin 100 mg once daily, in 81, 80, and 70 patients, respectively) after CABG underwent 13 C urea breath testing and EGD. Gastroduodenal lesions were assessed by modified Lanza score, and reflux esophagitis was evaluated according to Los Angeles classification. Additionally, at least one ulcer ≥ 5 mm was separately analyzed. RESULTS: Among 231 patients, EGD showed 28 (12.1%) with ulcers ≥ 5 mm, which were detected in 13.6% (11/81) of ticagrelor plus aspirin recipients, 8.8% (7/80) of ticagrelor recipients, and 14.3% (10/70) of aspirin recipients, and 24 (10.4%) had reflux esophagitis. Eighty-eight (38.1%) patients had a positive 13 C urea breath testing after 1 year of treatment, and one patient received eradication therapy during follow up. Nineteen (8.2%) patients received a PPI for ≥ 6 months. CONCLUSIONS: Severe upper gastrointestinal mucosal lesions were more frequently observed in patients treated with ticagrelor plus aspirin and aspirin monotherapy than in patients treated with ticagrelor monotherapy for 1 year post-CABG. Prophylactic use of PPIs might be inadequate.

7.
Phys Chem Chem Phys ; 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32123884

RESUMO

Correction for 'Predictable spectroscopic properties of type-II ZnTe/CdSe nanocrystals and electron/hole quenching' by Tongqing Long et al., Phys. Chem. Chem. Phys., 2019, 21, 5824-5833.

8.
J Hazard Mater ; 393: 122362, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32114133

RESUMO

Source tracking for heavy metals contained in road deposited sediments (RDS) is essential for pollution control and human health risk management. Previous studies on tracking sources for heavy metals have mostly been qualitative or semi-quantitative. This study quantitatively assessed the relative contributions of eight sources to five typical heavy metals in the urban environment using a chemical mass-balance based stochastic method. The results indicated that tire wear contributed the most masses to RDS (33 ± 26 %) while brake lining dusts contributed the least. Urban soil, tire wear, and brake lining dusts contributed the most to Pb (41 ± 32 %), Zn (28 ± 25 %), and Cu (59 ± 30 %), respectively, while gasoline engine exhaust was the main source of both Cr (29 ± 28 %) and Ni (20 ± 23 %). The outcomes also showed that tire wear and diesel engine exhaust have higher potential to threaten human health risk because they generate high amounts of heavy metals with high bioaccessibility. The research results can also provide a quantitative guidance for taking remediation actions of heavy metal control on urban road surfaces and measuring the effectiveness of those actions.

9.
Turk J Gastroenterol ; 31(1): 30-35, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32009611

RESUMO

BACKGROUND/AIMS: To determine the characteristics of small bowel tumors (SBTs) in patients underwent double balloon endoscopy (DBE) and to compare the clinical value of DBE with other diagnostic tools. MATERIALS AND METHODS: A retrospective study was conducted in patients underwent DBE procedures from March 2008 to April 2017.The demographic, clinical and pathological characteristics of patients with SBTs were recorded, while the diagnosis of SBTs was achieved either by DBE biopsy or surgical specimens. RESULTS: One thousand one hundred and two patients (761 males, range 3-85 years) were enrolled in this study, with 1140 procedures completed in total. 99/1102 patients (9.0%) had SBTs, including benign polyps (20, 20.2%), gastrointestinal stromal tumors (GISTs) (24, 24.2%), lymphomas (13, 13.1%), adenocarcinoma (39, 39.4%), and neuroendocrine tumors (3, 3.0%). The most common clinical symptom for benign polyps was obscure gastrointestinal bleeding (OGIB) (75.0%). But among patients with malignant SBTs, the main indication for DBE was chronic abdominal pain (43.8%), followed by OGIB (36.3%), vomit (10.0%), abnormal images (6.3%) and diarrhea (3.8%) (P<0.001). Moreover, SBTs were primarily located in the jejunum alone (40/99, 40.4%). DBE had better sensitivity (89.2%), specificity (95.2%), positive predictive value (PPV) (90.0%), and negative predictive value (NPV) (94.8%) than other tools for suspected SBTs. CONCLUSION: Small bowel tumor is mainly located in jejunum and with OGIB and abdominal pain as major complaints. DBE is a reliable method for the diagnosis of SBTs compared with other diagnostic tools.

10.
Biomed Res Int ; 2020: 1824183, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32025516

RESUMO

Agaricus blazei, a type of edible straw-rotting mushroom with somewhat sweet taste and fragrance of almonds, has attracted considerable scientific and practical attention. High-throughput Illumina PE150 and PacBio RSII platform were employed to generate a genomic sequence. De novo assembly generated 36 contigs with 38,686,133 bp in size, containing 10,119 putative predicted genes. Additionally, we also studied transcriptional regulation of the mycelia and the primordia for exploration of genes involved in fruiting body formation. Expression profiling analysis revealed that 2,164 genes were upregulated in mycelia and 1,557 in primordia. Functional enrichment showed that differentially expressed genes associated with response to stress, ribosome biogenesis, arginine biosynthesis, and steroid biosynthesis pathway were more active in fruiting body. The genome and transcriptome analysis of A. blazei provide valuable sequence resources and contribute to our understanding of genes related to the biosynthesis pathway of polysaccharide and benzaldehyde, as well as the fruiting body formation.

11.
Phys Chem Chem Phys ; 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32104817

RESUMO

The structure and stability of two-dimensional hydrogen hydrate were investigated in this work using density functional theory. The results are in line with expectations that the occupied cages are more stable after their confinement between two parallel hydrophobic sheets. The four two-dimensional hydrogen hydrate crystals - BLHH-I, BLHH-II, BLHH-III and BLHH-IV - that we predicted were much more stable in a restricted environment than in a free environment, even close to or exceeding conventional hydrogen hydrates. Besides, we found that the stability of two-dimensional hydrates is inversely related to the increase in temperature. Our work highlights that two-dimensional hydrates provide a new research idea in the field of hydrogen storage.

12.
FEBS Lett ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32049361

RESUMO

Adenosine deaminase acting on RNA 1 (ADAR1) has been shown to participate in the regulation of endothelial cells (ECs), as well as local and systemic inflammatory responses. Here, we find that bacterial lipopolysaccharide (LPS)-induced upregulation of ADAR1 in lung ECs is impaired in aged mice, an animal model with high rates of sepsis and mortality. Endothelial cell-specific ADAR1 knockout (ADAR1ECKO ) mice suffer from higher mortality rates, aggravated lung injury, and increased vascular permeability under LPS challenge. In primary ADAR1 knockout ECs, expression of the melanoma differentiation-associated gene 5 (MDA5), a downstream effector of ADAR1, is significantly elevated. MDA5 knockout completely rescues the postnatal offspring death of ADAR1ECKO mice. However, there is no reduction in mortality or apoptosis in lung cells of ADAR1ECKO /MDA5-/- mice challenged with LPS, indicating the involvement of an MDA5-independent mechanism in this process.

14.
Microsc Microanal ; 26(2): 310-318, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32051051

RESUMO

Exosomes derived from hepatocellular carcinoma (HCC) cells are nanovesicles and are involved in the occurrence and development of HCC, they also serve as important carriers and drug targets of nanodrug delivery systems. The external shape and internal structure of exosomes are important indexes of identification, and isolated intact morphology is crucial to biological function integrity. However, given their susceptibility to various influencing factors, the external shape and internal structure of exosomes derived from HCC cells remain incompletely studied. In this study, exosomes purified from HCC cells were isolated at different centrifugation speeds and examined via multiple electron microscopy (EM) techniques. The results demonstrate that exosomes possess a nearly spherical shape and bilipid membranous vesicle with a concave cavity structure containing electron-dense and coated vesicles, suggesting the possible existence of subpopulations of exosomes with specific functions. The exosomes isolated at ultracentrifugation (UC) speed (≥110,000×g) presented irregular and diverse external morphologies, indicating the effect on the integrity of the exosomes. Transforming growth factor signaling bioactive substances (TGF-ß1, S100A8, and S100A9) can be found in exosomes by performing Western blotting, showing that the internal content is associated with metastasis of HCC. These findings show that EMelectron microscopy and UC speed can affect exosome characteristics, including external shape, internal structure, and content of bioactive substances. The electron-dense and coated vesicles that had been discovered in exosomes might become new additional morphological features, which could help to improve the interpretation of experimental results and widen our understanding of exosome morphology.

15.
FASEB J ; 34(2): 2524-2540, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31908026

RESUMO

The main mechanism of hyaluronidase 1(HYAL-1) in the development of postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD) was unknown. In this study, a comprehensive inventory of pre-, intra-, and postoperative clinical and biological data of two cohorts (62 pancreatic cancer [PCa] and 111 pancreatic ductal adenocarcinoma [PDAC]) which could induce POPF were retrospectively analyzed. Then, a total of 7644 genes correlated with HYAL-1 was predicted in PDAC tissues and the enriched pathway, kinase targets and biological process of those correlated genes were evaluated. Finally, a mouse pancreatic fistula (PF) model was first built and in vitro studies were performed to investigate the effects of HYAL-1 on PF progression. Our data indicated that preoperative serum HYAL-1 level, pancreatic fibrosis score, and pancreatic duct size were valuable factors for detecting POPF of Grade B and C. The serum HYAL-1 level of 2.07 mg/ml and pancreatic fibrosis score of 2.5 were proposed as the cutoff values for indicating POPF. The bioinformatic analysis and in vitro and in vivo studies demonstrated that HYAL-1 facilitates pancreatic acinar cell autophagy via the dephosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK) and signal transducers and activators of transcription 3 (STAT3) signaling pathways, which exacerbate pancreatic secretion and inflammation. In summary, the preoperative serum HYAL-1 was a significant predictor for POPF in patients who underwent PD. Tumor-induced HYAL-1 is one of core risk in accelerating PF and then promoting pancreatic secretion and acute inflammation response through the AMPK and STAT3-induced autophagy.

16.
J Am Chem Soc ; 142(5): 2150-2154, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31955571

RESUMO

The reaction between SO3 and water in the gas phase has always been of great interest, as it has important implications in atmospheric and environmental science. Compared to gas-phase water, however, heterogeneous hydration of SO3 on the surfaces of condensed phases of water/ice is relatively less explored. Here, we present a systematic study of the reactions between SO3 and three different phases of water, namely, water vapor, the surface of a liquid water droplet, and the {1 1 -2 0} plane of hexagonal ice (Ih). The computational results show that, contrary to the gas-phase water, the surface of a water droplet and the {1 1 -2 0} plane of Ih ice play distinctly different roles in the reaction, in which the HSO4-/H3O+ is formed within a few picoseconds. Moreover, the SO3 hydration exhibits multiple reaction pathways on the surface of a water droplet and the {1 1 -2 0} plane of Ih ice, including a newly observed chemical mechanism without the formation of water-loop structures. Considering temperature effects (winter vs summer), SO3/water vapor concentrations in the atmosphere, and the effective surface areas of water droplets in the atmosphere and ice on the ground, the reaction rates of SO3 with water in the gas phase, in aerosols, in clouds, and on snowpack are estimated and compared. Consistent with previous experimental studies, the loss rates of SO3 due to aerosols and clouds are less important compared to that due to water vapor. Surprisingly, the ice snowpack is shown to be an efficient sink for SO3 depletion, especially in the winter season.

17.
Inorg Chem ; 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31999443

RESUMO

Thiol-amine solvent mixtures have been widely applied in the solution processing of binary chalcogenide thin films due to their excellent ability to dissolve various bulk binary chalcogenides. However, application of this solvent system in preparing new crystalline chalcogenidometalates has not been explored. In this work, by using a thiol-amine solvent mixture of n-butylamine (BA) and 1,2-ethanedithiol (EDT) as the reaction medium and protonated piperazine (pip) cation as the template, we synthesized a series of new chalcogenidoarsenates with structures ranging from discrete clusters to two-dimensional layers, namely, [pipH2][pipH][AsS4] (1), [pipH2][pipH][As(Se0.4S0.6)4] (2), [pipH2]2[pipH]2[In2AsIII2AsV2S13.3(S2)0.7] (3), [pipH2]2[pipH]2[In2AsIII2AsV2S10.2Se3.1(Se2)0.7] (4), [pipH2]0.5[AsS(S2)] (5), [pipH2]0.5[AsS2] (6), [pipH]2[AgAsS4] (7), [pipH2]1.5[GaAsIIIAsVS7] (8), and Cs2[pipH]2[InAs6S12]Cl (9). Particularly, compounds 3, 4, and 8 contain mixed-valent AsIII and AsV ions in their discrete clusters and one-dimensional chain. In addition, compound 5 could thermodynamically transform to compound 6 with increasing reaction temperature, which may be attributed to the thermodynamically unstable S-S species in the chains of 5. The BA-EDT solvent mixture was crucial to the synthesis of these compounds, since no title crystals can be prepared by replacing the BA-EDT solvent mixture with other conventional solvents or removing one component of the BA-EDT solvent mixture from the reaction system. Our research demonstrates that thiol-amine solvent systems could be promising reaction media for growing novel crystalline chalcogenidometalates.

18.
Anat Rec (Hoboken) ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31922655

RESUMO

Yin-deficiency-heat (YDH) syndrome is a very common subhealth status in Traditional Chinese Medicine. However, currently, there is no unified standard for diagnosing YDH syndrome. We applied the iTRAQ-2D LC-MS/MS method to explore the potential of serum protein profiles as biomarker for YDH syndrome. A total of 120 differentially expressed proteins (79 downregulated and 41 upregulated) were identified by the proteomic profiling. The results of KEGG pathway analysis showed that the functions of the differentially expressed proteins were mainly involved in complement and coagulation cascades. The clinical data showed that YDH syndrome was closely related to inflammation and coagulation, compared with the healthy controls. The ELISA validation results indicated that the expression levels of ALB, CFI, and KLKB1 were downregulated in the YDH syndrome group (p < .05). Moreover, we established a decision tree model based on the combination of these three proteins and achieved a sensitivity of 87.5%, a specificity of 84.4%, and AUC of 0.891. The results indicated that the combination of ALB, CFI, and KLKB1 may serve as potential biomarkers for diagnosing YDH syndrome. Our study can provide a new method for YDH syndrome diagnosis, and may also provide an experimental basis to understand the molecular mechanism of YDH syndrome.

19.
Infect Dis Poverty ; 9(1): 2, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900215

RESUMO

BACKGROUND: Understanding the global spatiotemporal pattern of seasonal influenza is essential for influenza control and prevention. Available data on the updated global spatiotemporal pattern of seasonal influenza are scarce. This study aimed to assess the spatiotemporal pattern of seasonal influenza after the 2009 influenza pandemic. METHODS: Weekly influenza surveillance data in 86 countries from 2010 to 2017 were obtained from FluNet. First, the proportion of influenza A in total influenza viruses (PA) was calculated. Second, weekly numbers of influenza positive virus (A and B) were divided by the total number of samples processed to get weekly positive rates of influenza A (RWA) and influenza B (RWB). Third, the average positive rates of influenza A (RA) and influenza B (RB) for each country were calculated by averaging RWA, and RWB of 52 weeks. A Kruskal-Wallis test was conducted to examine if the year-to-year change in PA in all countries were significant, and a universal kriging method with linear semivariogram model was used to extrapolate RA and RB in all countries. RESULTS: PA ranged from 0.43 in Zambia to 0.98 in Belarus, and PA in countries with higher income was greater than those countries with lower income. The spatial patterns of high RB were the highest in sub-Saharan Africa, Asia-Pacific region and South America. RWA peaked in early weeks in temperate countries, and the peak of RWB occurred a bit later. There were some temperate countries with non-distinct influenza seasonality (e.g., Mauritius and Maldives) and some tropical/subtropical countries with distinct influenza seasonality (e.g., Chile and South Africa). CONCLUSIONS: Influenza seasonality is not predictable in some temperate countries, and it is distinct in Chile, Argentina and South Africa, implying that the optimal timing for influenza vaccination needs to be chosen with caution in these unpredictable countries.


Assuntos
Influenza Humana/epidemiologia , Pandemias/estatística & dados numéricos , Vigilância da População , Humanos , Influenza Humana/virologia , Estações do Ano , Análise Espacial , Análise Espaço-Temporal
20.
Biomed Eng Online ; 19(1): 4, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941515

RESUMO

BACKGROUND: Site-specific variations are challenges for pooling analyses in multi-center studies. This work aims to propose an inter-site harmonization method based on dual generative adversarial networks (GANs) for diffusion tensor imaging (DTI) derived metrics on neonatal brains. RESULTS: DTI-derived metrics (fractional anisotropy, FA; mean diffusivity, MD) are obtained on age-matched neonates without magnetic resonance imaging (MRI) abnormalities: 42 neonates from site 1 and 42 neonates from site 2. Significant inter-site differences of FA can be observed. The proposed harmonization approach and three conventional methods (the global-wise scaling, the voxel-wise scaling, and the ComBat) are performed on DTI-derived metrics from two sites. During the tract-based spatial statistics, inter-site differences can be removed by the proposed dual GANs method, the voxel-wise scaling, and the ComBat. Among these methods, the proposed method holds the lowest median values in absolute errors and root mean square errors. During the pooling analysis of two sites, Pearson correlation coefficients between FA and the postmenstrual age after harmonization are larger than those before harmonization. The effect sizes (Cohen's d between males and females) are also maintained by the harmonization procedure. CONCLUSIONS: The proposed dual GANs-based harmonization method is effective to harmonize neonatal DTI-derived metrics from different sites. Results in this study further suggest that the GANs-based harmonization is a feasible pre-processing method for pooling analyses in multi-center studies.

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