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1.
Int J Biol Macromol ; 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32389651

RESUMO

A novel exopolysaccharide (EPS) with high molecular weight (3.65 × 105 Da) and film-forming ability was produced by the strain Kosakonia sp. CCTCC M2018092. Partially acid hydrolyzed EPS (AH-EPS) with high content of fucose was prepared and exhaustively characterized. The molecular weight of AH-EPS was determined to be 3.47 × 104 Da. GC-MS and HPLC analyses indicated that AH-EPS is composed of L-fucose, d-glucose, D-galactose, D-glucuronic acid and pyruvic acid in the molar ratio of 2.03:1.00:1.18:0.64:0.67. Chemical and NMR analyses revealed that AH-EPS is an anionic heteropolysaccharide, with a major linkage structural motif as follows. Utilizing AH-EPS as reducing and stabilizing agent, silver nanoparticles (AH-EPS@Ag NPs) with uniform size (diameter about 20 nm) were synthesized through a green method. A hybrid film containing EPS and AH-EPS@Ag NPs was further prepared, and its antibacterial effectiveness to Staphylococcus aureus was confirmed. Taken together, this work revealed the structural characteristics of a novel fucose-rich polysaccharide, with good potential in developing new biodegradable antibacterial film.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32378163

RESUMO

Atrial fibrillation (AF) is the most common arrhythmia with diverse etiology that remarkably relates to high morbidity and mortality. With the advancements in intensive clinical and basic research, the understanding of electrophysiological and pathophysiological mechanism, as well as treatment of AF have made huge progress. However, many unresolved issues remain, including the core mechanisms and key intervention targets. Big data approach has produced new insights into the improvement of the situation. A large amount of data have been accumulated in the field of AF research, thus using the big data to achieve prevention and precise treatment of AF may be the direction of future development. In this review, we will discuss the current understanding of big data and explore the potential applications of big data in AF research, including predictive models of disease processes, disease heterogeneity, drug safety and development, precision medicine, and the potential source for big data acquisition. Grapical abstract.

3.
New Phytol ; 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32406528

RESUMO

C2H2-type zinc finger transcription factor STOP1 plays an essential role in aluminum (Al) resistance in Arabidopsis thaliana by controlling the expression of a set of Al-resistance genes including the malate transporter-encoding gene AtALMT1 that is critically required for Al resistance. STOP1 is suggested to be modulated by Al at posttranscriptional and/or posttranslational levels. However, the underlying molecular mechanisms remain to be demonstrated. We carried out a forward genetic screen on an EMS-mutagenized population, which contains the AtALMT1 promoter-driven luciferase reporter gene (pAtALMT1:LUC), and identified HPR1, which encodes a subunit of the THO/TREX complex. We investigate the effect of hpr1 mutations on the expression of Al-resistance genes and Al resistance, and we also examined the regulatory role of HPR1 in nuclear mRNA and protein accumulation of STOP1 gene. Mutation of HPR1 reduces the expression of STOP1-regulated genes and the associated Al resistance. The hpr1 mutations increase STOP1 mRNA retention in the nucleus and consequently decrease STOP1 protein abundance. Mutation of RAE1 that mediates STOP1 degradation in the hpr1 mutant background can partially rescue the deficient phenotypes of hpr1 mutants. Our results demonstrate that HPR1 modulates Al resistance partly through the regulation of nucleocytoplasmic STOP1 mRNA export.

4.
J Hazard Mater ; 396: 122693, 2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32353735

RESUMO

Nanoplastics (NPs) and microplastics (MPs) are a heterogeneous class of pollutants with diverse sizes in aquatic environments. To evaluate the hazardous effects of N/MPs with different sizes, the accumulation, oxidative stress, cytochrome P450 (CYP) enzymes, neurotoxicity, and metabolomics changes were investigated in the red tilapia exposed to three sizes of polystyrene (PS) N/MPs (0.3, 5, and 70 - 90 µm). After 14-d exposures, the largest particles (70 - 90 µm) showed the highest accumulation levels in most cases. Exposures to PS-MPs (5 and 70 - 90 µm) caused a more severe oxidative stress in red tilapia than PS-NPs. The activity of CYP3A-related enzyme was obviously inhibited by PS-NPs, whereas the CYP enzymes in the liver may not be sensitive to MP exposures. In the brain, only 5 µm PS-MPs significantly inhibited the acetylcholinesterase activity. After exposures, the treatments with 0.3, 5, and 70 - 90 µm N/MPs resulted in 31, 40, and 23 significantly differentially expressed metabolites, respectively, in which the pathway of tyrosine metabolism was significantly affected by all the three PS-N/MP exposures. Overall, the PS particles within the µm size posed more severe stress to red tilapia. Our results suggest that the toxicity of N/MPs may not show a simply monotonic negative correlation with their sizes.

5.
Sci Rep ; 10(1): 7369, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32355265

RESUMO

The problem of urban waterlogging has consistently affected areas of southern China, and has generated widespread concerns among the public and professionals. The geographically weighted regression model (GWR) is widely used to reflect the spatial non-stationarity of parameters in different locations, with the relationship between variables able to change with spatial position. In this research, Shenzhen City, which has a serious waterlogging problem, was used as a case study. Several key results were obtained. (1) The spatial autocorrelation of flood spot density in Shenzhen was significant at the 5% level, but because the Z value was not large it was not very obvious. (2) The degree of impact on flood disasters from large to small was: Built up_ DIVISION > SHDI > Built up_ COHESION > CONTAG > Built up_ LPI. (3) The degree of waterlogging disasters in higher altitude regions was less affected by the landscape pattern. The results of this study highlight the important role of the landscape pattern on waterlogging disasters and also indicate the different impacts of different regional landscape patterns on waterlogging disasters, which provides useful information for planning the landscape pattern and controlling waterlogging.

6.
Meat Sci ; 167: 108172, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32422547

RESUMO

Lamb meat is cooked using different methods which help to impart good taste, flavour and aroma and they also improve the nutritional quality and ensure food safety. However traditional methods also induce some potential health hazards i.e. formation of polyaromatic hydrocarbons, heterocyclic aromatic amines and acrylamides. These harmful compounds are produced through protein aggregation (protein increased with loss of water), lipid degradation (lipid breakdown due to cooking), oxidation (radicals formation due to heat and oxygen combination), and the Maillard reaction (reaction between sugars and amino acids). This review focuses on: 1) the use of modern cooking technologies to reduce the generation of hazardous compounds by a) applying low temperature cooking with minimum contact with the meat; b) faster cooking, with the added benefits of minimum nutritional losses and less energy consumption 2) the adoption of natural plant sources as extracts to: a) inhibit lipid oxidation; b) improve the stability of meat products to limit the generation of hazardous compounds.

7.
Dalton Trans ; 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32432241

RESUMO

Owing to the combination of intriguing activity and conductivity, hybrid compositions of layered double hydroxides (LDHs) and carbon-based materials have been extensively and widely applied to evolve oxygen gas during water splitting. Here, a facile in situ nucleation strategy was used to construct ultrafine NiFe-LDH nanosheets monodispersed on a carbon black (CB) substrate. Notably, this work displayed the interfacial impact of combining CB with NiFe-LDHs on electrocatalyst activation. Interestingly, the optimized NiFe-LDHs/CB composite displays a fast activation rate and excellent water oxidation performance on a glassy-carbon electrode (an overpotential of 226 mV at 10 mA cm-2; a Tafel slope of 57 mV dec-1). This is due to the high active area, low impedance and ultra-high active metal atom utilization rate, accelerating charge transfer at the interface during the activation process. More importantly, this work highlights the interfacial charge transfer effect during the activation process and supplies clues for designing electrocatalysts.

8.
AIDS Patient Care STDS ; 34(5): 193-204, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32396477

RESUMO

HIV nonoccupational postexposure prophylaxis (nPEP) has been prescribed to men who have sex with men (MSM) for decades, but the global situation of nPEP implementation among this population remains unclear. To understand nPEP awareness, uptake, and factors associated with uptake among MSM, we searched PubMed, Scopus, Embase, the Cochrane Library, and Web of Science for studies reporting nPEP implementation among MSM published before May 19, 2019. We estimated pooled rates and their 95% confidence intervals (CIs) of awareness, uptake using a random-effects model. We identified 74 studies: 3 studies (4.1%) from upper-middle-income regions and 71 (95.9%) from high-income regions. The pooled rate of nPEP awareness and uptake was 51.6% (95% CI 40.6-62.5%) and 6.0% (5.0-7.1%), respectively. Pooled uptake rate was higher in upper-middle-income regions [8.9% (7.8-10.0%)] than in high-income regions [5.8% (4.8-6.9%)]. Unprotected anal sex was the most common exposure (range: 55.0-98.6%, median: 62.9%). Pooled completion of nPEP was 86.9% (79.5-92.8%). Of 19,546 MSM prescribed nPEP, 500 HIV seroconversions (2.6%) were observed. Having risky sexual behaviors and history of sexually transmitted infections were associated with higher nPEP uptake, whereas insufficient knowledge, underestimated risk of exposure to HIV, lack of accessibility, and social stigma might hinder nPEP uptake. Awareness and uptake of nPEP among MSM worldwide are low. Further efforts are needed to combat barriers to access nPEP, including improving accessibility and reducing stigma. Seroconversions post-nPEP uptake suggest that joint prevention precautions aside from nPEP are needed for high-risk MSM. More evidence from low-income and middle-income regions is needed.

9.
Exp Lung Res ; : 1-9, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32372722

RESUMO

Purpose: Impaired mucociliary clearance is an initial characteristic of recurrent cough, respiratory infection and chronic respiratory diseases. It has been demonstrated that prolonged inhalation of respirable silica particles results in a variety of pulmonary diseases, but whether the mucociliary system is involved in this process is unclear. This study aims to evaluate the effects of silica particles on mucociliary structure and MUC5B production in respiratory tract.Materials and Methods: C57BL/6 mice were administered with 2.5 mg silica particles through a single intratracheal instillation. The changes of mucociliary structure and MUC5B expression in trachea was evaluated by HE and AB-PAS staining, transmission electron microscopy and immunohistochemistry on days 1, 7, 28 and 84 post-exposure.Results: The mucociliary structure of airway epithelium was obviously impaired by silica particles, showing disordered, shortened or partially lost cilia on the surface, increased mucus in mucous layer and submucosal glands from day 7 to day 84. A variety of ultrastructural abnormalities were discovered in silica-exposed airway cilia, including absence of central pair microtubules, disorganized microtubules and clusters of axoneme on day 1 and 7. The numbers of ciliary axonemes and basal bodies in ciliated epithelial cells were significantly decreased, whereas the proportion of abnormal axonemes was gradually increased with exposure to silica particles (P < 0.05). In addition, silica particles significantly decreased MUC5B expression on the surface of airway epithelium on day 28 and 84, but obviously increased its production in submucosal glands from day 1 to day 84 (P < 0.01).Conclusions: Silica particles could lead to ultrastructural defects in airway cilia, mucus hypersecretion and altered MUC5B expression in trachea, indicating that impaired mucociliary structure and altered MUC5B production might participate in the development of silica-related respiratory diseases.

10.
World Neurosurg ; 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32360922

RESUMO

STUDY DESIGN: A retrospective study. OBJECTIVE: To explore (1) whether the degree of facet joint distraction during single-segment anterior cervical discectomy and fusion for cervical spondylotic radiculopathy affects functional outcome and (2) whether the degree of facet joint distraction is related to cervical sagittal parameters. METHODS: This study retrospectively analyzed data from 72 patients with single-segment cervical spondylotic radiculopathy from January 2013 to December 2018. Lateral cervical radiographs were performed preoperatively and 12 months postoperatively. Disc height, interfacet distance and segmental angle were measured from the lateral cervical radiographs to evaluate facet joint distraction, and cervical sagittal parameters were measured. The outcome measures included VAS score and NDI score. RESULTS: Sixty-eight patients were included.ΔInterfacet distance was statistically significant in relation to ΔVAS score (P < 0.01). ROC curve analysis: less than the mean ΔVAS score for all patients was set as a positive result, and the critical value of Δinterfacet distance was 0.7 mm (p=0.024, AUC=0.659, sensitivity =46.8%, specificity =78.8%). According to the critical value determined by the ROC curve, all patients were divided into the appropriate distraction group (AD group) or the excessive distraction group (ED group). There was a significant difference in VAS scores between the two groups (P < 0.05). CONCLUSION: After undergoing single-segment ACDF for the treatment of cervical spondylotic radiculopathy, patients with an interfacet distance of 0.7 mm or more had worse VAS pain scores. However, this was not related to the improvement in postoperative NDI scores; changes in the interfacet distance were not associated with changes in the cervical sagittal parameters.

11.
Sci Total Environ ; 732: 139276, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32438156

RESUMO

The wide applications of rare earth oxide nanoparticles (REO NPs) in various fields and their subsequent release into the environment have attracted the research of their effects on organisms. In this study, the toxicity of yttrium oxide (Y2O3) NPs to tobacco BY-2 cells was evaluated and the importance of phosphate in the medium on the toxicity of Y2O3 NPs was revealed. 50 mg L-1 Y2O3 NPs induced 52.4% cellular growth inhibition after 24-h exposure. Phosphate inhibited the release of Y3+ from Y2O3 NPs from 6.00 to 0.04 mg L-1 at 24 h, thus reduced the toxicity of Y2O3 NPs. The surface charge of Y2O3 NPs changed from 24.0 mV (in deionized water) to -7.6 mV (in phosphate solution), which induced the aggregation of Y2O3 NPs. The change of surface properties reduced the direct nanotoxicity of Y2O3 NPs. High-resolution transmission electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy, and X-ray diffraction results demonstrated that phosphate transformed the surface of Y2O3 NPs to amorphous YPO4. This surface transformation decreased phosphate concentration in the medium. The dialysis membrane encapsulation experiment further identified the contribution percentage of direct nanotoxicity and indirect toxicity (i.e., phosphate depletion) of Y2O3 NPs to tobacco BY-2 cells in the presence of phosphate to be 68.3% and 31.7%, respectively. This study highlights the significant role of phosphate in altering the environmental behavior and toxicity of REO NPs.

12.
Sci Rep ; 10(1): 6760, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317739

RESUMO

To improve the performance of bamboo and increase its utilization value, this study aimed at investigating the effects of impregnation pretreatment and thermal treatment on the structural changes of bamboo. The samples were pretreated in sodium hydroxide or zinc chloride solution, and then treated at 160 °C. The pretreated and control samples were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TG), and Fourier transform infrared spectroscopy (FTIR). The results showed that the cellulose crystallinity and intensity of samples pretreated by ZnCl2 could be reduced, but the crystal structure remained the same. As for samples pretreated in NaOH, the crystal structure of fiber was destroyed and the crystallinity was increased significantly. High temperature treatment has little effect on the thermal stability of bamboo. However, after treatment with NaOH and ZnCl2, the thermal degradation temperature changed obviously and moved to a lower temperature. ZnCl2 pretreatment had influence on the chemical structure of bamboo, while NaOH pretreatment had greater influence on the chemical structure of bamboo.

13.
Cell Mol Neurobiol ; 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32333305

RESUMO

Fragile X-related protein 1 (FXR1) is a member of the fragile X family of RNA-binding proteins, which regulates a number of neurological and neuropsychiatric disorders such as fragile X syndrome, and is expected as a novel therapeutic target for some psychiatric diseases. However, it is unknown how FXR1 changes and functions in post-traumatic stress disorder (PTSD), a common mental disorder related to trauma and stressor. In this study, we characterized the expression pattern of FXR1 in the pathophysiological process of PTSD and further investigated the possible mechanism underlying these changes by finding an upstream regulator, namely miRNA-132 (miR-132). Furthermore, we verified whether miR-132 silence had an effect on the PTSD-like behaviors of single prolonged stress (SPS) rats through open field test, forced swimming test, and water maze test. At last, we examined the expression levels of PSD95 and synapsin I in the hippocampus, which was one of the key brain regions associated with PTSD. We showed that the levels of FXR1 and fragile X mental retardation protein (FMRP), an autosomal homolog of FXR1, were decreased in the hippocampus of PTSD rats, but the levels of PSD95 and synapsin I were increased, which could be reversed by downregulation of miR-132. The results revealed that miR-132 could modulate PTSD-like behaviors in rats following SPS through regulating FXR1 and FMRP.

14.
Food Funct ; 11(4): 3351-3360, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32226997

RESUMO

Developing food protein structures with the freedom to tune their internal molecular arrangements is a fascinating aspect for serving the demands of multifunctional food components. However, a protein's conformation is highly submissive to its amino acid sequences, posing a great limitation on controlling its structural rearrangements. In this study, based on simply co-dissolving scallop muscle proteins (SMPs, water-insoluble) and soya proteins (SPs) at pH 12 prior to neutralization, the unfolding-folding pathways of both proteins were altered. Structural characterizations evidenced the complexation of SMPs and SPs using their secondary structures as the building blocks. Due to hydrophobic coalition between the α-helix (from SMPs) and ß-sheet (from SPs), the co-assembled structures obtained considerable resistance against folding triggered by the hydrophobic effect. In addition, the kinetics by which the SMPs and SPs folded together was tailor-made by the compositional differences of the two proteins, resulting in the formation of well-defined, water-dispersible nanospheres with a tunable size and internal arrangements of the backbones. This study would enrich our choice of manipulated protein structures and enlarge the available protein sources with tailorable functions when applied in specific scenarios.

15.
Water Res ; 176: 115735, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32224330

RESUMO

Graphene oxide (GO) sheets are unstable in aqueous environments, and the effect of photo-transformation on GO toxicity to freshwater algae (Chlorella pyrenoidosa) was investigated. Our results demonstrated that GO underwent photo-reduction under 25-day sunlight irradiation, and the transformation was generally completed at Day 8. The toxicological investigation showed that 8-day sunlight irradiation significantly increased growth inhibition of GO (25 mg/L) to algal cells by 11.2%, due to enhanced oxidative stress and stronger membrane damage. Low molecular weight (LMW) species were produced during the 8-day GO transformation, and they were identified as two types of aromatic compounds, which played a crucial role in increasing toxicity. The combined toxicity of GO and Cu2+ ions before and after light irradiation was further investigated. Antagonistic effect was observed between the toxicity of pristine GO and co-existing Cu2+ ions. After co-irradiation of GO and Cu2+ ions for 8 days, their combined toxicity was unexpectedly lower or insignificant in comparison with the treatments of pristine GO, or pristine GO in the presence of Cu2+ ions. Two mechanisms were revealed for this finding: (1) Cu2+ ions suppressed the photo-transformation of GO; (2) the toxicity of free Cu2+ ions was decreased through the adsorption/retention of Cu2+ ions and formation of Cu-based nanoparticles (e.g., Cu2O and Cu2S) on the photo-transformed GO. The provided data are helpful for better understanding the environmental process and risk of GO under natural conditions.


Assuntos
Chlorella , Grafite , Poluentes Químicos da Água , Água Doce , Íons , Metais
16.
Biochem Biophys Res Commun ; 526(3): 699-705, 2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32253029

RESUMO

Alzheimer's disease (AD) is the commonest neurodegenerative disease and, in recent years, studies have increasingly shown that vascular lesions are involved in the pathology of AD onset and progression. Many vascular changes precede the pathological changes and clinical symptoms of AD, and vascular lesions and AD have many common risk factors. Understanding the relationship between vascular factors and the pathological process of AD may help us to identify novel prevention and treatment strategies as well as delay disease progress. Previous studies have shown that lycopene has neuroprotective, antioxidant, and anticancer effects; however, the specific molecular mechanism mediating these effects remains unknown. In the present study, we found: 1) lycopene improved learning and memory in an AD mouse model; 2) lycopene inhibited amyloid plaque aggregation and neuroinflammation; and 3) lycopene induced LXR expression and activated the LXR-PI3K-AKT signaling pathway. Our findings suggest that promotion of neurogenesis and improvement of the functions of the neurovascular unit could be a novel direction for the development of AD therapies.

17.
World Neurosurg ; 2020 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-32289511

RESUMO

OBJECTIVE: In this retrospective study, our objective was to establish a nomogram to predict the effectiveness of cervical traction in young and middle-aged chronic nonspecific neck pain (CNNP) patients with unsatisfactory nonsteroidal anti-inflammatory drug (NSAID) control. For CNNP patients with unsatisfactory NSAID control, the effectiveness of cervical traction varies. Neck muscle fat infiltration and clinical features may associate with the effectiveness. METHODS: A total of 186 suitable patients were classified into a training data set (from August 2015 to July 2018, n = 118) and a validation data set (from August 2018 to June 2019, n = 68) with time sequence. All patients were included to receive magnetic resonance imaging scan to calculate posterior cervical fat and muscle features, then undergoing unified cervical traction in an outpatient clinic. The least absolute shrinkage and selection operator (LASSO) regression model was used to select potentially relevant features to predict effectiveness possibility of cervical traction. Multivariable logistic regression analysis was used to develop the predicting model, presenting with a nomogram. The performance of the nomogram was assessed based on its calibration, discrimination, and clinical utility. RESULTS: Through the LASSO regression model, we identified 4 predictors including sex, good exercise compliance, the ratio of the cross-sectional area (CSA) between fat and muscle on C5 level (C5 fat CSA/muscle CSA), the ratio of CSA between fat and centrum on C5 level (C5 fat CSA/centrum muscle CSA). The nomogram provided good calibration and discrimination in the training cohort, showing an area under the curve (AUC) of 0.704 (95% CI, 0.608-0.799) and good concordance between the predicted and actual probabilities with Spiegelhalter's Z-test (P = 0.835). Discrimination of the model in the validation data set was acceptable, with AUC of 0.691 (95% CI, 0.564-0.817). Decision curve analysis revealed the nomogram to be clinically useful. CONCLUSIONS: Male sex, good exercise compliance, lower C5 fat CSA/centrum CSA, and and lower C5 fat CSA/muscle CSA could be favorable features to predict the effectiveness of cervical traction in CNNP patients with unsatisfactory NSAID control.

18.
Int J Biol Macromol ; 155: 393-402, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32224182

RESUMO

Fermentation technology was used to improve the antioxidant activities of Auricularia auricula polysaccharide (AAP). Response surface methodology (RSM) was used to optimize the fermentation conditions. The effects of 4 independent factors: water content (X1: 40-80%), inoculation amount (X2: 2-20%), temperature (X3: 24-32 °C), and time (X4: 4-6 d) on the biological degradation efficiency were evaluated. The RSM results showed that the optimal fermentation conditions were: X1: 61.7%, X2: 12.4%, X3: 31.0 °C, X4: 5.5 d. Verification tests showed no significant differences between the practical and the predictive values for each response. Under the optimal conditions, the degradation rate was 26.89 ± 0.14%, without significant differences with the predicted value (27.03%). The degradation products were classified to different molecular weight (Mw) polysaccharide fragments using membrane separation technology. The FT-IR analysis and monosaccharide composition analysis of degraded AAP (D-AAP-VI) showed that D-AAP-VI was a furan type polysaccharide, which was different from the total AAP (pyran type). In addition, compared to total AAP, the antioxidant activities in vitro of D-AAP-VI were significantly improved (p < 0.05) and D-AAP-VI showed the strongest antioxidant activity. These results indicated that biological degradation may be a suitable way to improve the antioxidant activities of natural polysaccharides.

19.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 36(1): 86-94, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32314728

RESUMO

Objective The comprehensive test is adaptable to medical integration education and is an effective way to evaluate students' performance and assess the effects of teaching reform. Given the special characteristics of the comprehensive test, this paper is designed to apply item response theory to immunology test question analysis in the comprehensive test of basic medicine, illustrating the method of applying the theory to the medical test evaluation and elaborating its role and significance in quality control of medical comprehensive test. Methods The software e-irt and SPSS were used to analyze 180 immunology test questions from the comprehensive test of basic medicine for six years. All parameters were calculated and then equated to produce characteristic curve and information function curve. Results The immunology test questions from the comprehensive test of basic medicine was of high reliability, but of lower difficulty value and discrimination value than the overall level of the comprehensive test paper. The test parameters and examinees' ability showed significant differences among the six years. The quality of certain immunology test questions did not meet the ideal standard, which is required to be analyzed. Conclusion Medical integration education facilitates the process of our students acquiring immunology knowledge. The item response theory can be effectively applied to comparing the papers, questions and examinees' abilities among the years on the same scale, thus presenting the existing problems in terms of question quality, teaching process and examines' abilities, improving the quality of test questions, and facilitating the establishment of a standardized examination database.

20.
Liver Int ; 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32250535

RESUMO

BACKGROUND: Few studies have examined the risk of gastrointestinal cancers in screen-detected gallstone disease. This study aimed to investigate the association between screen-detected gallstone disease and gastrointestinal cancers using the Kailuan cohort, a population-based prospective cohort initiated in 2006. METHODS: A total of 79,809 men who underwent gallbladder ultrasonography, were free of cancers in 2006 and did not have gastrointestinal cancers within one year were enrolled. A Cox proportional hazards model with age as the timescale was used to evaluate the association between screen-detected gallstone disease and gastrointestinal cancers. RESULTS: We identified 1,264 cases with gastrointestinal cancers, including 303 cases with liver cancer and 94 cases with pancreatic cancer. Screen-detected gallstone disease increased the risk of liver cancer, with an HR of 2.28 [95% confidence interval (CI): 1.20-4.33, p=0.012]. The association was modified by the hepatitis B surface antigen status. A non-significant positive association was observed between pancreatic cancer and gallstone disease (HR 2.19, 95% CI: 0.95-5.05, p=0.065). However, the HR became significant after those individuals with diabetes were excluded (HR 2.60, 95% CI: 1.12-6.01, p=0.026). CONCLUSION: Screen-detected gallstone disease may predict the risk for liver and pancreatic cancer.

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