Neuromyelitis optica spectrum disorder-related optic neuritis involves various cellular responses to inflammation and degeneration.In most patients,the primary mechanism underlying neuromyelitis optica spectrum disord...Neuromyelitis optica spectrum disorder-related optic neuritis involves various cellular responses to inflammation and degeneration.In most patients,the primary mechanism underlying neuromyelitis optica spectrum disorder-related optic neuritis is the interaction of aquaporin-4 antibodies with the aquaporin-4 protein present on astrocytes within posterior optic nerve.This binding subsequently initiates a cascade of events leading to secondary demyelination of the optic nerve,ultimately culminating in optic nerve degeneration.Earlier studies on this disorder primarily used systemic-induced animal models,which often require prior activation of a systemic immune response.This can result in primary demyelination of the optic nerve,complicating the interpretation of experimental results.Such methodologies hinder the ability to isolate immune responses triggered by specific antibodies.Additionally,the lack of a detailed profile of disease progression over time limits our capacity to identify potential intervention windows.Therefore,constructing a targeted optic neuritis animal model induced by specific antibodies and elucidate the disease progression arecrucial for exploring the mechanisms underlying neuromyelitis optica spectrum disorder-related optic neuritis.In this study,specific antibodies against aquaporin-4 were precisely injected into the retrobulbar optic nerve of mice to induce a targeted inflammatory response in the posterior optic nerve,resulting in a more representative mouse model of neuromyelitis optica spectrum disorder-related optic neuritis than current models.The progression of the disease was then dynamically observed from both histological and functional perspectives over the course of 1 month following the induction of inflammation.By the first week,astrocytes were damaged,as evidenced by the loss of aquaporin-4 and glial fibrillary acidic protein,the activation of microglia,and the upregulation of microglia-related cytokines,including tumor necrosis factor,interleukin-6,interleukin-1β,C-X-C motif ligand 10,and brain-derived neurotrophic factor.Starting from the second week,there were signs of optic nerve demyelination and significant damage to axonal fibers and retinal ganglion cell bodies.Visual-evoked potentials and dark adaptation threshold responses in electroretinogram both indicated dysfunction in the visual pathway and retina,while optical coherence tomography revealed thinning of the retinal nerve fiber layer in live mice.In summary,in this study we conducted a dynamic exploration of the occurrence and progression of neuromyelitis optica spectrum disorder-related optic neuritis triggered by specific antibodies.Our results show pathological changes at various stages and correlate histological and molecular alterations with in vivo structural and functional deterioration.The findings from this study lay an important foundation for further research on neuromyelitis optica spectrum disorder-related optic neuritis.展开更多
Securing restricted zones such as airports,research facilities,and military bases requires robust and reliable access control mechanisms to prevent unauthorized entry and safeguard critical assets.Face recognition has...Securing restricted zones such as airports,research facilities,and military bases requires robust and reliable access control mechanisms to prevent unauthorized entry and safeguard critical assets.Face recognition has emerged as a key biometric approach for this purpose;however,existing systems are often sensitive to variations in illumination,occlusion,and pose,which degrade their performance in real-world conditions.To address these challenges,this paper proposes a novel hybrid face recognition method that integrates complementary feature descriptors such as Fuzzy-Gabor 2D Fisher Linear Discriminant(FG-2DFLD),Generalized 2D Linear Discriminant Analysis(G2DLDA),andModular-Local Binary Patterns(Modular-LBP)with Dempster–Shafer(DS)evidence theory for decision fusion.The proposed framework extracts global,structural,and local texture features,models them using Gaussian distributions to estimate belief factors,and fuses these belief factors through DS theory to explicitly handle uncertainty and conflict among descriptors.Experimental validation was performed on two widely used benchmark datasets,ORL and Cropped Yale B,achieving recognition rates exceeding 98%,which outperform traditional methods as well as recent deep learning-based approaches.Furthermore,the method demonstrated strong robustness under noisy conditions,maintaining accuracies above 96%with salt-and-pepper and Gaussian noise.These results highlight the effectiveness of the proposed integration strategy in enhancing accuracy,reliability,and resilience compared to single-descriptor and conventional fusion methods.Given its high performance and efficiency,the proposed method shows strong potential for deployment in real-world restricted-zone applications such as smart parking systems,secure facility access,and other high-security domains.展开更多
目的探讨慢性阻塞性肺疾病(COPD)患者血清G蛋白偶联受体43(GPR43)、甲基转移酶3(METTL3)水平表达与肺功能和气流受限程度的相关性。方法选取2019年1月~2024年5月成都市第六人民医院收治的COPD患者150例(COPD组)和同期健康体检志愿者150...目的探讨慢性阻塞性肺疾病(COPD)患者血清G蛋白偶联受体43(GPR43)、甲基转移酶3(METTL3)水平表达与肺功能和气流受限程度的相关性。方法选取2019年1月~2024年5月成都市第六人民医院收治的COPD患者150例(COPD组)和同期健康体检志愿者150例(对照组)。根据气流受限程度将COPD患者分为轻度组(n=61)、中度组(n=46)和重度/极重度组(n=43)。检测血清GPR43、METTL3水平并测定肺功能[第1秒用力呼气容积(FEV1)/用力肺活量(FVC)、FEV1占预计值%(%pred)]。Spearman相关性分析血清GPR43、METTL3水平与肺功能指标的相关性;通过多元有序Logistic回归分析血清GPR43、METTL3水平与COPD患者气流受限程度的关系,使用受试者工作特征(ROC)曲线分析其评估效能。结果与对照组比较,COPD组血清GPR43水平(5.32±1.07ng/ml vs 7.61±1.59ng/ml),FEV1/FVC比值[54.17(43.77,63.60)%vs 80.78(76.24,88.22)%]和FEV1%pred[72.25(44.94,84.22)%vs 93.06(89.71、95.54)%]显著降低(t/Z=-14.591,-14.247,-14.108),而METTL3水平(41.73±5.27pg/ml vs 31.85±5.03pg/ml)显著升高(t=16.614),差异具有统计学意义(均P<0.001)。重度/极重度组血清GPR43水平低于轻度、中度组(4.57±0.77ng/ml vs 5.98±1.05ng/ml、5.16±0.79 ng/ml),中度组低于轻度组(t=7.474、3.598、4.391),重度/极重度组血清METTL3水平高于轻度组、中度组(45.76±5.24pg/ml vs 38.83±4.20pg/ml、41.82±4.00pg/ml),中度组高于轻度组(t=-7.474、-4.003、-3.722),差异具有统计学意义(均P<0.001)。COPD患者FEV1/FVC比值、FEV1%pred与血清GPR43水平呈正相关(r=0.762、0.768,均P<0.001),与METTL3水平呈负相关(r=-0.758、-0.778,均P<0.001)。GPR43为COPD气流受限的独立保护因素(OR=0.689,Waldχ^(2)=14.064,P<0.05),METTL3为独立危险因素(OR=1.251,Waldχ^(2)=4.500,P<0.05)。血清GPR43与METTL3联合评估COPD重度/极重度气流受限的曲线下面积(AUC)优于GPR43和METTL3单独检测,差异具有统计学意义(Z=3.231、3.374,均P<0.05)。结论COPD患者血清GPR43水平降低、METTL3水平升高,与肺功能降低和气流受限程度加重有关,血清GPR43,METTL3水平联合评估COPD患者重度/极重度气流受限的价值较高。展开更多
Protein Kinase G(PKG)is an important intracellular signal transduction enzyme,and its activity is modulated by cyclic guanosine monophosphate(cGMP).PKG plays a pivotal role in various significant physiological process...Protein Kinase G(PKG)is an important intracellular signal transduction enzyme,and its activity is modulated by cyclic guanosine monophosphate(cGMP).PKG plays a pivotal role in various significant physiological processes,including vascular smooth muscle relaxation,myocardial cell function regulation,neuron growth,and synaptic plasticity,et al.In recent years,the role of PKG in diseases has gradually attracted attention,and the abnormalities in its signaling pathway are closely related to the occurrence and development of cardiovascular and neurological diseases.Although PKG has been widely studied,its complex functions in different physiological systems and potential innovative applications still need to be further explored.This article reviews the purification techniques for PKG,discusses the advantages and disadvantages of different extraction methods,summarizes the structure and activation mechanism of each domain of PKG,and analyzes the physiological functions of PKG in organisms,especially the well-established roles in the cardiovascular system,nervous system,and endocrine system.The emerging therapeutic applications of PKG are also reviewed.In addition,the challenges of this field are proposed at the end.展开更多
Vitamins are natural materials essential for maintaining the normal physical function of the live cells. It has been reported that 13 vitamins are needed in our body, included vitamin A, B vitamins （thiamine, ribofla...Vitamins are natural materials essential for maintaining the normal physical function of the live cells. It has been reported that 13 vitamins are needed in our body, included vitamin A, B vitamins （thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, biotin, folic acid and cobalamin）, vitamin C, vitamin D, vitamin E and vitamin K. Nowadays, the functions of vitamins have been extensively investigated. The objective of this paper is to summarize the new functions of vitamins, aiming to provide suggestions on the usage of various vitamins in clinical application.展开更多
AIM: To investigate the relationship between gastric dysmotility,gastrointestinal hormone abnormalities, and neuroendocrine cells in gastrointestinal mucosa in patients with functional dyspepsia (FD).METHODS: Gastric ...AIM: To investigate the relationship between gastric dysmotility,gastrointestinal hormone abnormalities, and neuroendocrine cells in gastrointestinal mucosa in patients with functional dyspepsia (FD).METHODS: Gastric emptying was assessed with solid radiopaque markers in 54 FD patients, and the patients were divided into two groups according to the results, one with delayed gastric emptying and the other with normal gastric emptying. Seventeen healthy volunteers acted as normal controls. Fasting and postprandial plasma levels and gastroduodenal mucosal levels of gastrointestinal hormones gastrin, somatostatin (SS) and neurotensin (NT)were measured by radioimmunoassay in all the subjects.G cells (gastrin-producing cells) and D cells (SS-producing cells) in gastric antral mucosa were immunostained with rabbit anti-gastrin polyclonal antibody and rabbit anti-SS polyclonal antibody, respectively, and analyzed quantitatively by computerized image analysis.RESULTS: The postprandial plasma gastrin levels, the fasting and postprandial plasma levels and the gastric and duodenal mucosal levels of NT were significantly higher in the FD patients with delayed gastric emptying than in those with normal gastric emptying and normal controls. The number and gray value of G and D cells and the G cell/D cell number ratio did not differ significantly between normal controls and the FD patients with or without delayed gastric emptying.CONCLUSION: Our findings suggest that the abnormalities of gastrin and NT may play a role in the pathophysiology of gastric dysmotility in FD patients, and the abnormality of postprandial plasma gastrin levels in FD patients with delayed gastric emptying is not related to the changes both in the number and gray value of G cells and in the G cell/D cell number ratio in gastric antral mucosa.展开更多
Background:The independent and interactive effects of dietary fiber(DF)and threonine(Thr)were investigated in growing pigs challenged with either systemic E.coli lipopolysaccharide(LPS)or enteric Salmonella Typhimuriu...Background:The independent and interactive effects of dietary fiber(DF)and threonine(Thr)were investigated in growing pigs challenged with either systemic E.coli lipopolysaccharide(LPS)or enteric Salmonella Typhimurium(ST)to characterise their effect on intestinal barrier function.Results:In experiment 1,intestinal barrier function was assessed via oral lactulose and mannitol(L:M)gavage and fecal mucin analysis in pigs challenged with E.coli LPS and fed low fiber(LF)or high fiber(HF)diets with graded dietary Thr.Urinary lactulose recovery and L:M ratio increased(P<0.05)during the LPS inoculation period in LF fed pigs but not in HF fed pigs.Fecal mucin output was increased(P<0.05)in pigs fed HF compared to LF fed pigs.In experiment 2,RT-qPCR,ileal morphology,digesta volatile fatty acid(VFA)content,and fecal mucin output were measured in Salmonella Typhimurium challenged pigs,fed LF or HF diets with standard or supplemented dietary Thr.Salmonella inoculation increased(P<0.05)fecal mucin output compared to the unchallenged period.Supplemental Thr increased fecal mucin output in the HF-fed pigs(Fib×Thr;P<0.05).Feeding HF increased(P<0.05)VFA concentration in cecum and colon.No effect of either Thr or fiber on expression of gene markers was observed except a tendency(P=0.06)for increased MUC2 expression with the HF diet.Feeding HF increased goblet cell numbers(P<0.05).Conclusion:Dietary fiber appears to improve barrier function through increased mucin production capacity(i.e.,goblet cell numbers,MUC2 gene expression)and secretion(i.e.,fecal mucin output).The lack of effect of dietary Thr in Salmonella-challenged pigs provides further evidence that mucin secretion in the gut is conserved and,therefore,Thr may be limiting for growth under conditions of increased mucin production.展开更多
This paper is aimed at detecting the neutron spectrum of^(241)Am–Be, a widely used neutron source, with the SP9 ~3He proportional counter, which is a multi-sphere spectrometer system of eight thermal neutron detector...This paper is aimed at detecting the neutron spectrum of^(241)Am–Be, a widely used neutron source, with the SP9 ~3He proportional counter, which is a multi-sphere spectrometer system of eight thermal neutron detectors embedded in eight polyethylene(PE) spheres of varying diameters. The transport processes of a neutron in the multi-sphere spectrometer are simulated using the Geant4 code. Two sets of response functions of the PE spheres are obtained for calculating the^(241)Am–Be neutron spectrum.Response Function 1 utilizes the thermal neutron scattering model G4 Neutron HPThermal Scattering for neutron energies of ≤4 eV, and Response Function 2 has no thermal treatment. Neutron spectra of an^(241)Am–Be neutron source are measured and compared to those calculated by using the response functions. The results show that response function with thermal treatment is more accurate and closer to the real spectrum.展开更多
In a recent article [Physics Letters A 372 （2008） 417], Wang et al. proposed a method, which is called the （G′/G）-expansion method, to look for travelling wave solutions of nonlinear evolution equations. The trav...In a recent article [Physics Letters A 372 （2008） 417], Wang et al. proposed a method, which is called the （G′/G）-expansion method, to look for travelling wave solutions of nonlinear evolution equations. The travelling wave solutions involving parameters of the KdV equation, the mKdV equation, the variant Boussinesq equations, and the Hirota-Satsuma equations are obtained by using this method. They think the （G′/G）-expansion method is a new method and more travelling wave solutions of many nonlinear evolution equations can be obtained. In this paper, we will show that the （G′/G）-expansion method is equivalent to the extended tanh function method.展开更多
基金The study was partially supported by the General Research Fund(GRF)from the Research Grants Council(RGC)of the Hong Kong Special Administrative Region,China,No.15103522(to ST)the Internal Research Grant from the Hong Kong Polytechnic University 2021-23,No.P0035512(to ST)and P0035375(to HHLC)+1 种基金the Innovation and Technology Commission of the Hong Kong Special Administrative Region(ITC InnoHK CEVR Project)The Hong Kong Polytechnics University Research Center for Sharp Vision,No.P0039595.
文摘Neuromyelitis optica spectrum disorder-related optic neuritis involves various cellular responses to inflammation and degeneration.In most patients,the primary mechanism underlying neuromyelitis optica spectrum disorder-related optic neuritis is the interaction of aquaporin-4 antibodies with the aquaporin-4 protein present on astrocytes within posterior optic nerve.This binding subsequently initiates a cascade of events leading to secondary demyelination of the optic nerve,ultimately culminating in optic nerve degeneration.Earlier studies on this disorder primarily used systemic-induced animal models,which often require prior activation of a systemic immune response.This can result in primary demyelination of the optic nerve,complicating the interpretation of experimental results.Such methodologies hinder the ability to isolate immune responses triggered by specific antibodies.Additionally,the lack of a detailed profile of disease progression over time limits our capacity to identify potential intervention windows.Therefore,constructing a targeted optic neuritis animal model induced by specific antibodies and elucidate the disease progression arecrucial for exploring the mechanisms underlying neuromyelitis optica spectrum disorder-related optic neuritis.In this study,specific antibodies against aquaporin-4 were precisely injected into the retrobulbar optic nerve of mice to induce a targeted inflammatory response in the posterior optic nerve,resulting in a more representative mouse model of neuromyelitis optica spectrum disorder-related optic neuritis than current models.The progression of the disease was then dynamically observed from both histological and functional perspectives over the course of 1 month following the induction of inflammation.By the first week,astrocytes were damaged,as evidenced by the loss of aquaporin-4 and glial fibrillary acidic protein,the activation of microglia,and the upregulation of microglia-related cytokines,including tumor necrosis factor,interleukin-6,interleukin-1β,C-X-C motif ligand 10,and brain-derived neurotrophic factor.Starting from the second week,there were signs of optic nerve demyelination and significant damage to axonal fibers and retinal ganglion cell bodies.Visual-evoked potentials and dark adaptation threshold responses in electroretinogram both indicated dysfunction in the visual pathway and retina,while optical coherence tomography revealed thinning of the retinal nerve fiber layer in live mice.In summary,in this study we conducted a dynamic exploration of the occurrence and progression of neuromyelitis optica spectrum disorder-related optic neuritis triggered by specific antibodies.Our results show pathological changes at various stages and correlate histological and molecular alterations with in vivo structural and functional deterioration.The findings from this study lay an important foundation for further research on neuromyelitis optica spectrum disorder-related optic neuritis.
文摘Securing restricted zones such as airports,research facilities,and military bases requires robust and reliable access control mechanisms to prevent unauthorized entry and safeguard critical assets.Face recognition has emerged as a key biometric approach for this purpose;however,existing systems are often sensitive to variations in illumination,occlusion,and pose,which degrade their performance in real-world conditions.To address these challenges,this paper proposes a novel hybrid face recognition method that integrates complementary feature descriptors such as Fuzzy-Gabor 2D Fisher Linear Discriminant(FG-2DFLD),Generalized 2D Linear Discriminant Analysis(G2DLDA),andModular-Local Binary Patterns(Modular-LBP)with Dempster–Shafer(DS)evidence theory for decision fusion.The proposed framework extracts global,structural,and local texture features,models them using Gaussian distributions to estimate belief factors,and fuses these belief factors through DS theory to explicitly handle uncertainty and conflict among descriptors.Experimental validation was performed on two widely used benchmark datasets,ORL and Cropped Yale B,achieving recognition rates exceeding 98%,which outperform traditional methods as well as recent deep learning-based approaches.Furthermore,the method demonstrated strong robustness under noisy conditions,maintaining accuracies above 96%with salt-and-pepper and Gaussian noise.These results highlight the effectiveness of the proposed integration strategy in enhancing accuracy,reliability,and resilience compared to single-descriptor and conventional fusion methods.Given its high performance and efficiency,the proposed method shows strong potential for deployment in real-world restricted-zone applications such as smart parking systems,secure facility access,and other high-security domains.
文摘目的探讨慢性阻塞性肺疾病(COPD)患者血清G蛋白偶联受体43(GPR43)、甲基转移酶3(METTL3)水平表达与肺功能和气流受限程度的相关性。方法选取2019年1月~2024年5月成都市第六人民医院收治的COPD患者150例(COPD组)和同期健康体检志愿者150例(对照组)。根据气流受限程度将COPD患者分为轻度组(n=61)、中度组(n=46)和重度/极重度组(n=43)。检测血清GPR43、METTL3水平并测定肺功能[第1秒用力呼气容积(FEV1)/用力肺活量(FVC)、FEV1占预计值%(%pred)]。Spearman相关性分析血清GPR43、METTL3水平与肺功能指标的相关性;通过多元有序Logistic回归分析血清GPR43、METTL3水平与COPD患者气流受限程度的关系,使用受试者工作特征(ROC)曲线分析其评估效能。结果与对照组比较,COPD组血清GPR43水平(5.32±1.07ng/ml vs 7.61±1.59ng/ml),FEV1/FVC比值[54.17(43.77,63.60)%vs 80.78(76.24,88.22)%]和FEV1%pred[72.25(44.94,84.22)%vs 93.06(89.71、95.54)%]显著降低(t/Z=-14.591,-14.247,-14.108),而METTL3水平(41.73±5.27pg/ml vs 31.85±5.03pg/ml)显著升高(t=16.614),差异具有统计学意义(均P<0.001)。重度/极重度组血清GPR43水平低于轻度、中度组(4.57±0.77ng/ml vs 5.98±1.05ng/ml、5.16±0.79 ng/ml),中度组低于轻度组(t=7.474、3.598、4.391),重度/极重度组血清METTL3水平高于轻度组、中度组(45.76±5.24pg/ml vs 38.83±4.20pg/ml、41.82±4.00pg/ml),中度组高于轻度组(t=-7.474、-4.003、-3.722),差异具有统计学意义(均P<0.001)。COPD患者FEV1/FVC比值、FEV1%pred与血清GPR43水平呈正相关(r=0.762、0.768,均P<0.001),与METTL3水平呈负相关(r=-0.758、-0.778,均P<0.001)。GPR43为COPD气流受限的独立保护因素(OR=0.689,Waldχ^(2)=14.064,P<0.05),METTL3为独立危险因素(OR=1.251,Waldχ^(2)=4.500,P<0.05)。血清GPR43与METTL3联合评估COPD重度/极重度气流受限的曲线下面积(AUC)优于GPR43和METTL3单独检测,差异具有统计学意义(Z=3.231、3.374,均P<0.05)。结论COPD患者血清GPR43水平降低、METTL3水平升高,与肺功能降低和气流受限程度加重有关,血清GPR43,METTL3水平联合评估COPD患者重度/极重度气流受限的价值较高。
基金supported by the National Natural Science Foundation of China(Nos.22374033,22174031,22407037)the Natural Science Foundation of Heilongjiang Province(No.ZD2022B001).
文摘Protein Kinase G(PKG)is an important intracellular signal transduction enzyme,and its activity is modulated by cyclic guanosine monophosphate(cGMP).PKG plays a pivotal role in various significant physiological processes,including vascular smooth muscle relaxation,myocardial cell function regulation,neuron growth,and synaptic plasticity,et al.In recent years,the role of PKG in diseases has gradually attracted attention,and the abnormalities in its signaling pathway are closely related to the occurrence and development of cardiovascular and neurological diseases.Although PKG has been widely studied,its complex functions in different physiological systems and potential innovative applications still need to be further explored.This article reviews the purification techniques for PKG,discusses the advantages and disadvantages of different extraction methods,summarizes the structure and activation mechanism of each domain of PKG,and analyzes the physiological functions of PKG in organisms,especially the well-established roles in the cardiovascular system,nervous system,and endocrine system.The emerging therapeutic applications of PKG are also reviewed.In addition,the challenges of this field are proposed at the end.
文摘Vitamins are natural materials essential for maintaining the normal physical function of the live cells. It has been reported that 13 vitamins are needed in our body, included vitamin A, B vitamins （thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, biotin, folic acid and cobalamin）, vitamin C, vitamin D, vitamin E and vitamin K. Nowadays, the functions of vitamins have been extensively investigated. The objective of this paper is to summarize the new functions of vitamins, aiming to provide suggestions on the usage of various vitamins in clinical application.
文摘AIM: To investigate the relationship between gastric dysmotility,gastrointestinal hormone abnormalities, and neuroendocrine cells in gastrointestinal mucosa in patients with functional dyspepsia (FD).METHODS: Gastric emptying was assessed with solid radiopaque markers in 54 FD patients, and the patients were divided into two groups according to the results, one with delayed gastric emptying and the other with normal gastric emptying. Seventeen healthy volunteers acted as normal controls. Fasting and postprandial plasma levels and gastroduodenal mucosal levels of gastrointestinal hormones gastrin, somatostatin (SS) and neurotensin (NT)were measured by radioimmunoassay in all the subjects.G cells (gastrin-producing cells) and D cells (SS-producing cells) in gastric antral mucosa were immunostained with rabbit anti-gastrin polyclonal antibody and rabbit anti-SS polyclonal antibody, respectively, and analyzed quantitatively by computerized image analysis.RESULTS: The postprandial plasma gastrin levels, the fasting and postprandial plasma levels and the gastric and duodenal mucosal levels of NT were significantly higher in the FD patients with delayed gastric emptying than in those with normal gastric emptying and normal controls. The number and gray value of G and D cells and the G cell/D cell number ratio did not differ significantly between normal controls and the FD patients with or without delayed gastric emptying.CONCLUSION: Our findings suggest that the abnormalities of gastrin and NT may play a role in the pathophysiology of gastric dysmotility in FD patients, and the abnormality of postprandial plasma gastrin levels in FD patients with delayed gastric emptying is not related to the changes both in the number and gray value of G cells and in the G cell/D cell number ratio in gastric antral mucosa.
基金Funding for this project was provided by Alberta Agriculture and Forestry Strategic Research and Development Section,Evonik Nutrition&Care GmbH,and Mitacs Accelerate.
文摘Background:The independent and interactive effects of dietary fiber(DF)and threonine(Thr)were investigated in growing pigs challenged with either systemic E.coli lipopolysaccharide(LPS)or enteric Salmonella Typhimurium(ST)to characterise their effect on intestinal barrier function.Results:In experiment 1,intestinal barrier function was assessed via oral lactulose and mannitol(L:M)gavage and fecal mucin analysis in pigs challenged with E.coli LPS and fed low fiber(LF)or high fiber(HF)diets with graded dietary Thr.Urinary lactulose recovery and L:M ratio increased(P<0.05)during the LPS inoculation period in LF fed pigs but not in HF fed pigs.Fecal mucin output was increased(P<0.05)in pigs fed HF compared to LF fed pigs.In experiment 2,RT-qPCR,ileal morphology,digesta volatile fatty acid(VFA)content,and fecal mucin output were measured in Salmonella Typhimurium challenged pigs,fed LF or HF diets with standard or supplemented dietary Thr.Salmonella inoculation increased(P<0.05)fecal mucin output compared to the unchallenged period.Supplemental Thr increased fecal mucin output in the HF-fed pigs(Fib×Thr;P<0.05).Feeding HF increased(P<0.05)VFA concentration in cecum and colon.No effect of either Thr or fiber on expression of gene markers was observed except a tendency(P=0.06)for increased MUC2 expression with the HF diet.Feeding HF increased goblet cell numbers(P<0.05).Conclusion:Dietary fiber appears to improve barrier function through increased mucin production capacity(i.e.,goblet cell numbers,MUC2 gene expression)and secretion(i.e.,fecal mucin output).The lack of effect of dietary Thr in Salmonella-challenged pigs provides further evidence that mucin secretion in the gut is conserved and,therefore,Thr may be limiting for growth under conditions of increased mucin production.
基金supported by ITER Plan National Major Project(No.2008GB109000)the Introduces Talents Scientific Research Project of Guizhou University(2014,No.32)
文摘This paper is aimed at detecting the neutron spectrum of^(241)Am–Be, a widely used neutron source, with the SP9 ~3He proportional counter, which is a multi-sphere spectrometer system of eight thermal neutron detectors embedded in eight polyethylene(PE) spheres of varying diameters. The transport processes of a neutron in the multi-sphere spectrometer are simulated using the Geant4 code. Two sets of response functions of the PE spheres are obtained for calculating the^(241)Am–Be neutron spectrum.Response Function 1 utilizes the thermal neutron scattering model G4 Neutron HPThermal Scattering for neutron energies of ≤4 eV, and Response Function 2 has no thermal treatment. Neutron spectra of an^(241)Am–Be neutron source are measured and compared to those calculated by using the response functions. The results show that response function with thermal treatment is more accurate and closer to the real spectrum.
基金Supported by National Natural Science Foundation of China under Grant No. 10671172
文摘In a recent article [Physics Letters A 372 （2008） 417], Wang et al. proposed a method, which is called the （G′/G）-expansion method, to look for travelling wave solutions of nonlinear evolution equations. The travelling wave solutions involving parameters of the KdV equation, the mKdV equation, the variant Boussinesq equations, and the Hirota-Satsuma equations are obtained by using this method. They think the （G′/G）-expansion method is a new method and more travelling wave solutions of many nonlinear evolution equations can be obtained. In this paper, we will show that the （G′/G）-expansion method is equivalent to the extended tanh function method.
