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1.
Biomed Res Int ; 2022: 8547379, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093404

RESUMO

The potential threat of global warming in the 21st century is on the ecosystem through many aspects, including the negative impact of rising global temperature on the health of humans and animals, especially domestic animals. The damage caused by heat stress to animals has been more and more significant as the worldwide climate continues to rise, along with the breeding industry's expanding scale and stocking density, and it has become the most important stress-causing factor in southern China. In this review, we described the effects of heat stress on animal immune organs and immune system. The much-debated topic is how hyperthermia affects the tight junction barrier. Heat stress also induces inflammation in the body of animals causing low body weight and loss of appetite. This review also discussed that heat stress leads to hepatic disorder, and it also damages the intestine. The small intestine experiences ischemia, and the permeability of the intestine increases. Furthermore, the oxidative stress and mitogen-activated protein kinase (MAPK) pathways have a significant role in stress-induced cellular and organ injury. The study has shown that MAPK activity in the small intestine was increased by heat stress. Heat stress caused extreme small intestine damage, enhanced oxidative stress, and activated MAPK signaling pathways.


Assuntos
Ecossistema , Proteínas de Junções Íntimas , Animais , Biodiversidade , Resposta ao Choque Térmico , Humanos , Intestinos , Temperatura , Proteínas de Junções Íntimas/metabolismo
2.
Food Funct ; 13(18): 9532-9543, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-35997017

RESUMO

Gut microbiota is well-established to regulate host blood pressure. Diosgenin is a natural steroid sapogenin with documented anti-inflammatory, antioxidant and antihypertensive properties. We aimed to investigate whether the antihypertensive effects of diosgenin are mediated by the microbiota-gut-brain axis in spontaneously hypertensive rats (SHR). 15-Week-old male Wistar Kyoto rats (WKY) and age-matched SHR were randomly distributed into three groups: WKY, SHR treated with a vehicle, and SHR treated with diosgenin (100 mg kg-1). Our results showed that diosgenin prevented elevated systolic blood pressure (SBP) and ameliorated cardiac hypertrophy in SHR. Moreover, the gut microbiota composition and intestinal integrity were improved. Furthermore, increased butyrate-producing bacteria and plasma butyrate and decreased plasma lipopolysaccharides were observed in SHR treated with diosgenin. These findings were associated with reduced microglial activation and neuroinflammation in the paraventricular nucleus. Our findings suggest that diosgenin attenuates hypertension by reshaping the gut microbiota and improving the gut-brain axis.


Assuntos
Diosgenina , Hipertensão , Sapogeninas , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Antioxidantes/farmacologia , Pressão Sanguínea , Encéfalo , Butiratos , Diosgenina/farmacologia , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Sapogeninas/farmacologia
3.
Sci Rep ; 11(1): 20608, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663855

RESUMO

Heat stress can significantly affect the immune function of the animal body. Heat stress stimulates oxidative stress in intestinal tissue and suppresses the immune responses of mice. The protecting effects of chitosan on heat stress induced colitis have not been reported. Therefore, the aim of this study was to investigate the protective effects of chitosan on immune function in heat stressed mice. Mice were exposed to heat stress (40 °C per day for 4 h) for 14 consecutive days. The mice (C57BL/6J), were randomly divided into three groups including: control group, heat stress, Chitosan group (LD: group 300 mg/kg/day, MD: 600 mg/kg/day, HD: 1000 mg/kg/day). The results showed that tissue histology was improved in chitosan groups than heat stress group. The current study showed that the mice with oral administration of chitosan groups had improved body performance as compared with the heat stress group. The results also showed that in chitosan treated groups the production of HSP70, TLR4, p65, TNF-α, and IL-10 was suppressed on day 1, 7, and 14 as compared to the heat stress group. In addition Claudin-2, and Occludin mRNA levels were upregulated in mice receiving chitosan on day 1, 7, and 14 of heat stress. Furthermore, the IL-6, IL-10, and TNF-α plasma levels were down-regulated on day 1, 7, and 14 of heat stress in mice receiving the oral administration of chitosan. In conclusion, the results showed that chitosan has an anti-inflammatory ability to tolerate hot environmental conditions.


Assuntos
Quitosana/farmacologia , Resposta ao Choque Térmico/imunologia , Resposta ao Choque Térmico/fisiologia , Animais , Quitosana/metabolismo , Colite/tratamento farmacológico , Colite/imunologia , Colite/metabolismo , Citocinas/análise , Citocinas/sangue , Resposta ao Choque Térmico/efeitos dos fármacos , Inflamação , Intestinos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo
4.
Brain Behav ; 11(5): e02118, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33835731

RESUMO

BACKGROUND: Previous studies have shown that the brain-derived neurotrophic factor (BDNF) rs6265 G > A polymorphism is closely related post-traumatic stress disorder (PTSD) risk. However, the results were not consistent. We therefore conducted a meta-analysis to explore the underlying relationships between BDNF rs6265 G > A polymorphism and PTSD risk. MATERIALS AND METHODS: Five online databases were searched, and all related studies were reviewed up to July 1, 2020. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated to examine the statistical power of each genetic model. In addition, heterogeneity, sensitivity accumulative analysis, and publication bias were examined to check the statistical power. RESULT: Overall, 16 publications involving 5,369 subjects were included in this systematic review and 11 case-control studies were analyses in meta-analysis. The pooled results indicated an increasing risk of A allele mutations with PTSD risk. Moreover, the sequential subgroup analysis also demonstrated some similar situations in Asian populations and other groups. CONCLUSION: Current meta-analysis suggests that the BDNF rs6265 G > A polymorphism might be involved in PTSD susceptibility.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Transtornos de Estresse Pós-Traumáticos/genética , Alelos , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único
5.
Chem Biodivers ; 17(12): e2000500, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33078897

RESUMO

We characterized a new cycloartane glycoside, herein known as aspleniumside F (1), along with five known compounds as kaempferol-3-O-[(6-O-(E)-feruloyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-galacopyranoside (2), quercetin-3-O-[(6-O-(E)-feruloyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranoside (3), kaempferol-3-O-[(6-O-(E)-caffeoyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranoside (4), kaempferol-3-O-[(6-O-(E)-caffeoyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranosyl-7-O-ß-D-glucopyranoside (5), and kaempferol-3-O-[(6-O-p-coumaroyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranosyl-7-O-ß-D-glucopyranoside (6), from Asplenium ruprechtii Sa. Kurata, a folk medicine widely used to treat Thromboangiitis obliterans in China, Japan, and Korea. Based on spectroscopic, mainly 1D-, 2D-NMR and (+)-HR-ESI-MS, analyses as well as through comparisons with previous reports, its chemical structure was determined as 3ß,24,30-tri-ß-D-glucopyranosyl-23,25-dihydroxycycloartane (= (23R,24R)-3ß,24-bis-(ß-D-glucopyranosyloxy)-23,25-dihydroxy-9ß-9,19-cyclolanostan-29-yl ß-D-glucopyranoside). According to the 1 H coupling constant of anomeric protons and co-TLC of the acid hydrolysate with D-glucose, all three glycoside groups in 1 were revealed as ß-D-glucopyranosyl. Furthermore, SOD-like antioxidant activity evaluation via IC50 of 12.43, 6.78, 9.12, 6.94 and 4.85 µM revealed that compounds 2-6 had bioactivity.


Assuntos
Glicosídeos/química , Traqueófitas/química , Triterpenos/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética
6.
Iran J Basic Med Sci ; 21(3): 318-324, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29511499

RESUMO

OBJECTIVES: To investigate the effect of miR-103 on the angiogenesis of ischemic stroke rats via targeting vascular endothelial growth factor (VEGF) at the molecular level. MATERIALS AND METHODS: Rat models had received the middle cerebral artery occlusion (MCAO) or sham operation before grouping, and cell models of oxygen-glucose deprivation (OGD) were performed. FITC-dextran, matrigel, and Trans-well assays were used to evaluate the vascular density, tube formation, and cell migration respectively. The expression levels of miR-103 and VEGF were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. Dual-luciferase assay was used for analyzing the targeting relationship between miR-103 and VEGF. RESULTS: We found the reduced miR-103 in rats after MCAO. Down-regulating miR-103 with the miR-103 inhibitor enhanced VEGF, ameliorated the neurological scores, decreased infarct volume, and increased vascular density in rats after MCAO. Besides, in OGD human umbilical vein endothelial cells (HUVECs), inhibition of miR-103 could promote the increase of tube length and the migration of cells. Additionally, we found that miR-103 could directly target VEGF and thereby lead to the down-expression of VEGF. Meanwhile, si-VEGF could reverse the effect of miR-103 inhibitor on angiogenesis in rats subjected to MCAO. CONCLUSION: Inhibition of miR-103 could promote ischemic stroke angiogenesis and reduce infarction volume via enhancing VEGF, which provides a new target for the clinical treatment of ischemic stroke.

7.
Sci Rep ; 6: 24073, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-27044405

RESUMO

Extracellular high mobility group box 1 (HMGB1) has been demonstrated to function as a proinflammatory cytokine and induces neuronal injury in response to various pathological stimuli in central nervous system (CNS). However, the regulatory factor involved in HMGB1-mediated inflammatory signaling is largely unclear. Regulatory RNase 1 (Regnase-1) is a potent anti-inflammation enzyme that can degrade a set of mRNAs encoding proinflammatory cytokines. The present study aims to determine the role of Regnase-1 in the regulation of HMGB1-mediated inflammatory injury in CNS. Cultured microglia and rat brain were treated with recombinant HMGB1 to examine the induction of Regnase-1 expression. Moreover, the role of Regnase-1 in modulating the expression of inflammatory cytokines and neuronal injury was then investigated in microglia by specific siRNA knockdown upon HMGB1 treatment. Results showed that HMGB1 could significantly induce the de novo synthesis of Regnase-1 in cultured microglia. Consistently, Regnase-1 was elevated and found to be co-localized with microglia marker in the brain of rat treated with HMGB1. Silencing Regnase-1 in microglia enhanced HMGB1-induced expression of proinflammatory cytokines and exacerbated neuronal toxicity. Collectively, these results suggest that Regnase-1 can be induced by HMGB1 in microglia and negatively regulates HMGB1-mediated neuroinflammation and neuronal toxicity.


Assuntos
Regulação da Expressão Gênica , Proteína HMGB1/metabolismo , Ribonucleases/metabolismo , Fatores de Transcrição/metabolismo , Animais , Encéfalo/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Sistema Nervoso Central/metabolismo , Citocinas/metabolismo , Inflamação , Masculino , Camundongos , Microglia/metabolismo , Neurônios/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Wistar , Proteínas Recombinantes/metabolismo , Transdução de Sinais
8.
J Neurochem ; 137(4): 576-88, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26991073

RESUMO

Preconditioning with ligands of toll-like receptors (TLRs) is a powerful neuroprotective approach whereby a low dose of stimulus confers significant protection against subsequent substantial brain damage by reprogramming the ischemia-activated TLRs signaling. Herein, we aim to explore whether preconditioning with recombinant high-mobility group box 1 (rHMGB1), one of the TLRs ligands, decreases cerebral ischemia-reperfusion injury (IRI). Rats were intracerebroventricularly pretreated with rHMGB1, 1 or 3 days before induction of middle cerebral artery occlusion. Results showed that preconditioning with rHMGB1 1 day, but not 3 days, prior to ischemia dramatically reduced neurological deficits, infarct size, brain swelling, cell apoptosis, and blood-brain barrier permeability. Interleukin-1R-associated kinase-M (IRAK-M), a critical negative regulator of TLRs signaling, was robustly increased in response to brain IRI and was further elevated by rHMGB1 pretreatment, indicating its role associated with the rHMGB1 preconditioning-mediated ischemic tolerance. In vitro and in vivo assays indicated that the induced IRAK-M expression was localized in microglia. In addition, TLR4 specific inhibitor TAK-242 abolished the neuroprotective effects and the induction of IRAK-M offered by rHMGB1 preconditioning. Collectively, our study demonstrates that rHMGB1 preconditioning is neuroprotective during cerebral IRI, which is associated with activated TLR4/IRAK-M signaling in microglia. We found that high-mobility group box 1 (HMGB1) pretreatment conditioned the brain against subsequent ischemia-reperfusion injury. We propose the following mechanism for HMGB1 preconditioning-mediated ischemic tolerance: through toll-like receptor TLR4, HMGB1 preconditioning magnifies the up-regulation of interleukin-1R-associated kinase-M (IRAK-M) induced by ischemia-reperfusion in microglia, resulting in the decreased phosphorylation of IRAK-1. These findings are helpful in understanding the endogenous mechanisms that counteract ischemic insults.


Assuntos
Isquemia Encefálica/terapia , Proteína HMGB1/uso terapêutico , Precondicionamento Isquêmico/métodos , Traumatismo por Reperfusão/terapia , Animais , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Linhagem Celular , Masculino , Camundongos , Ratos , Ratos Wistar , Proteínas Recombinantes/uso terapêutico , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(11): 3523-9, 2016 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30198662

RESUMO

As a secondary analysis method, reproducibility and reliability of near-infrared spectroscopy (NIRS) quantitative analysis are quite dependent on modelling process. In this paper, it is focused on outlier analysis for protein quantitative model of wheat based on NIRS. The purpose is to discuss the outlier effect in modelling process of complex sample set. The indicator of outliers is the deviation between two interpretative percentage curves in partial least squares regression (PLSR) modelling, when two percentage curves have significant deviation or departure point, the sample set should include the outliers. The innovative research work is the analysis and treatment of outliers. On the basis of sub-model ergodic calculation method, outliers can be gradually identified and picked-up. The standard deviation of model's prediction residual is used as the reference graduation to distinguish the degree of deviation. According to the degree of deviation from sample population, outliers can also be divided into significant outliers, relative outliers and potential outliers. In this paper, the significant outliers of the sample set are about 7.8%, and the relative outliers are about 15.6%. The outliers will pull normal samples apart from the ideal fitting line and make the dispersity increase. No matter modelling with removed outliers or weighted samples, the purpose is to make the fitting results of quantitative analysis modelling more inclined to majority samples, while reducing or eliminating the impact of outliers.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(9): 2665-71, 2015 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-26669187

RESUMO

The medium temperature black body (MTBB) is conventional high precision equipment used as spectral radiometric scale in infrared spectral region. However, in near-infrared (NIR) spectral region, there are few papers about spectral radiometric calibration by using MTBB, that is because NIR spectral region is the borderland of its effective spectral region. The main research of this paper is spectral radiometric calibration method by using MTBB in NIR spectral region. Accordingly, this paper is devoted mostly to a discussion of how the calibration precision could be affected by selecting different structural parameters of calibration model. The purpose of this paper is to present the results of research and provide technical reference for improving the traceability in NIR spectral radiometric calibration. In this paper, a NIR fiber coupled spectrometer, whose wavelength range covers from 950 to 1700 nm, has been calibrated by a MTBB with adjustable temperature range from 50 to 1050 °C. Concentrating on calibration process, two key points have been discussed. For one thing, the geometric factors of radiation transfer model of the calibration systems have been compared between traditional structure and fiber direct-coupled structure. Because the fiber direct-coupled model is simple and effective, it has been selected instead of traditional model based on the radiation transfer between two coaxial discs. So, it is an advantaged radiation transfer model for radiometric calibration of fiber coupled spectrometer. For another thing, the relation between calibration accuracy and structural parameters of calibration model has been analyzed intensively. The root cause is scale feature of attribute of calibration data itself, which is the nonlinear structure in scales of spectral data. So, the high precision calibration needs nonlinear calibration model, and the uniform sampling for scale feature is also very important. Selecting sample is an inevitable problem when the nonlinear model is explained by small sample dataset. As the analytic results, there are obviously influences for the calibration precision among different strategies of selecting model's structural parameters. The calibration precision, which is mathematical described by standard deviation of spectral data for calibration, could be from ±0.1% to ±1%.

11.
Asian Pac J Trop Med ; 8(2): 162-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25902033

RESUMO

OBJECTIVE: To investigate effects of herbal compound Yi Tang Kang on the spleen deficiency metabolic syndrome. METHODS: Forty male Wistar rats were randomly divided into two groups: the normal control group and the MS spleen deficiency syndrome group. The control group rats were fed with standard diet and water, while MS spleen deficiency syndrome group with high fat diet and low dose intraperitoneal injection of streptozocin, which swam to the endurance limit. After 12 weeks, the MS spleen deficiency syndrome group was randomly divided into two groups, with 13 rats in each group. Rats in model group were fed with high fat diet and continuouly administered with daily saline, and rats in intervention group with high fat diet were trated with traditional Chinese medicines Yi Tang Kang by gavage, 2 mL/200 g at the same time every day. 10 weeks later, the expression of serum proteomics was investigated through abdominal aortic puncture and separation of serum, using isotope labeling technique, high performance liquid chromatography and four bar-Orbitrap mass spectrometer. RESULTS: After treatment with traditional Chinese medicine yitangkang, in the model group, important carboxylesterase and retinal guanylate cyclase 2 precursor were upregulated. As for intervention group, these indesxes were raised, but immunoglobulin IgG, carnitine acetyltransferase, tubulin beta -5, and Gan Lu sugar binding protein C were down-regulated. At the same time, some new biological active substances, such as protein tyrosine kinase, beta glucosidase were also found. CONCLUSIONS: Traditional Chinese medicines Yi Tang Kang could regulate glucose and lipid metabolism in rats with spleen deficiency syndrome.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(8): 2218-24, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25474965

RESUMO

A three-dimensional Gabor filter was developed for classification of hyperspectral remote sensing image. This method is based on the characteristics of hyperspectral image and the principle of texture extraction with 2-D Gabor filters. Three-dimensional Gabor filter is able to filter all the bands of hyperspectral image simultaneously, capturing the specific responses in different scales, orientations, and spectral-dependent properties from enormous image information, which greatly reduces the time consumption in hyperspectral image texture extraction, and solve the overlay difficulties of filtered spectrums. Using the designed three-dimensional Gabor filters in different scales and orientations, Hyperion image which covers the typical area of Qi Lian Mountain was processed with full bands to get 26 Gabor texture features and the spatial differences of Gabor feature textures corresponding to each land types were analyzed. On the basis of automatic subspace separation, the dimensions of the hyperspectral image were reduced by band index (BI) method which provides different band combinations for classification in order to search for the optimal magnitude of dimension reduction. Adding three-dimensional Gabor texture features successively according to its discrimination to the given land types, supervised classification was carried out with the classifier support vector machines (SVM). It is shown that the method using three-dimensional Gabor texture features and BI band selection based on automatic subspace separation for hyperspectral image classification can not only reduce dimensions; but also improve the classification accuracy and efficiency of hyperspectral image.

13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(3): 746-53, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-23815934

RESUMO

This study was aimed to evaluate an effective and stable method for obtaining mesenchymal stem cells (MSC) and endothelial progenitor cells (EPC) from the rabbit bone marrow and to investigate the biological characteristics of MSC and EPC. Mononuclear cells were obtained from rabbit bone marrow using density gradient method, and were differentially adhered to the cell culture plate enclosed with fibronectin. Then, MSC and EPC were amplified with EGB-2MV medium. Trypan blue method was used to test the passage survival rate. Growth curve, MTT and DNA cycle were used to evaluate the proliferation ability of MSC and EPC. MSC were identified with induced differentiation into the osteoblasts and adipocytes, and their immune phenotype was detected by flow cytometry (FCM). EPC were characterized by the special digestion of Dil-ac-LDL, FITC-UEA-I, and the conjunction with CD133, VEGFR2/KDR and CD34, their purity was also calculated. The results indicated that the colony was obviously formed when the mononuclear cells were cultured for 24 hours and, 80% of the cells became long spindle and integrated at d 8. Cells, which were adhered for twice, were cultured with EGM-2MV medium, began to extend at d 3, and became strip-shaped and integrated for about 80% at d 8. Passage survival rates were more than 90% for both cells, and after passage 2 the growth curve was like "S". Optical density was changed obviously when the cells were cultured for 3 - 5 d, but there were no significant difference of cell cycles between MSC and EPC, which G0-G1 was (93.32 ± 1.65)% and (93.05 ± 1.95)% respectively. Positive rates were (99.7 ± 1.12)%, (99.1 ± 2.33)%, (4.8 ± 0.38)%, (6.8 ± 0.49)% and (0.4 ± 0.08)% for CD90, CD44, CD14, CD45 and CD79a respectively. MSC were identified by induced differentiation into osteoblasts and adipocytes. Positive rates of the EPC, which were adhered for twice and passaged 2, were (82.1 ± 3.4)% for fluorescent staining of Dil-ac-LDL and FITC-UEA-I, and (74.2 ± 3.2)%, (64.7 ± 4.3)% and (43.5 ± 1.5)% for CD133, VEGFR2/KDR and CD34 respectively. It is concluded that high-purity MSC can be obtained with density gradient and differential adhesion method, and high-proliferation EPC can be cultured with EGM-2MV medium in cell plates enclosed with fibronectin, so they may become the optimal seed cells for tissue engineering study.


Assuntos
Células da Medula Óssea/citologia , Células Endoteliais/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco/citologia , Animais , Adesão Celular , Diferenciação Celular , Proliferação de Células , Separação Celular/métodos , Células Cultivadas , Citometria de Fluxo , Imunofenotipagem , Coelhos
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(11): 2962-5, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23387158

RESUMO

To simplify the model and improve the precision of prediction model, latent projective graph (LPG) was used for variable selection. The original spectrum was processed by continuous wavelet transform (CWT), LPG was obtained by principal component analysis (PCA), and based on the assumption that collinear wavelengths might have the same contribution to the modeling, a few latent spectral variables were selected for establishing prediction model. The root mean square error of prediction (RMSEP) model was 0. 3454, better than other modeling methods. This work proved that variable selection with LPG could simplify the near-infrared spectral model effectively, and improve the precision of prediction model.


Assuntos
Modelos Teóricos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Triticum/química , Previsões , Proteínas de Plantas/química , Análise de Componente Principal/métodos , Máquina de Vetores de Suporte , Análise de Ondaletas
15.
Wei Sheng Yan Jiu ; 35(3): 363-6, 2006 May.
Artigo em Chinês | MEDLINE | ID: mdl-16921770

RESUMO

Study of dietary intakes is an approach that estimates the potential influence that toxic and nutritional chemicals land in human health. It is also an important measure to ensure that diet is safe and nutritional. In this review, the different methods in dietary intakes' estimation are introduced and the methods are compared. In conclusion the characteristic of the methods is discussed.


Assuntos
Inquéritos sobre Dietas , Dieta/estatística & dados numéricos , Análise de Alimentos/métodos , Necessidades Nutricionais , China , Ingestão de Energia , Humanos , Política Nutricional
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