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1.
Neurochem Res ; 48(5): 1334-1346, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36449198

RESUMO

Background Transplantation of extracellular vesicles (EVs) from stem cells is a feasible scheme for traumatic spinal cord injury (SCI). However, there is no relevant report about stem cells derived EVs loaded with curcumin for SCI treatment. Methods Mouse umbilical cord mesenchymal stem cells (MUMSCs) were incubated in the medium containing curcumin (20 µM) for 48 h. Extracellular vesicles (EVs) and curcumin-primed EVs (Cur-EVs) were collected by ultracentrifugation. Characterizations of EVs/Cur-EVs were analyzed by western blotting with CD9 and CD81 antibodies, transmission electron microscopy and nano-tracking analysis. Curcumin in the Cur-EVs was analyzed by high performance liquid phase chromatography at 430 nm wavelength. Immunofluorescence and in vivo imaging methods were used to confirm biocompatibility of EVs/Cur-EVs in vitro and in vivo. Mice with complete SCI were treated with EVs/Cur-EVs to compare the differences of locomotor function, inflammation, histological changes and remyelination. Results The isolated EVs and Cur-EVs from MUMSCs have good biocompatibility. Compared with the model mice, the locomotor function, inflammation and axonal regeneration of mice were significantly improved after injection of Cur-EVs/EVs. Furthermore, it is more effective for structural and functional recovery of complete SCI after the Cur-EVs treatment compared with the EVs treatment. In the lesioned regions, the macrophage polarization from M1 to M2 phenotype and axonal regeneration were significantly improved in the Cur-EVs group compared with the EVs group. Conclusions Our data suggested that EVs from MUMSCs might be a promising drug delivery vehicle of curcumin for the efficient and biocompatible treatment of severe SCI.


Assuntos
Curcumina , Vesículas Extracelulares , Células-Tronco Mesenquimais , Traumatismos da Medula Espinal , Ratos , Camundongos , Animais , Curcumina/farmacologia , Curcumina/uso terapêutico , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/patologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Cordão Umbilical , Medula Espinal/patologia
2.
Reprod Biomed Online ; 42(4): 842-848, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33736991

RESUMO

RESEARCH QUESTION: What is the association between serum anti-Müllerian hormone (AMH) concentrations and the number of utilizable embryos obtained per stimulation cycle of IVF/intracytoplasmic sperm injection (ICSI) in POSEIDON Groups 3 and 4? DESIGN: Retrospective cohort study of 412 cycles, in which patients in POSEIDON Groups 3 and 4 (antral follicle count [AFC] ≤5 and AMH <1.2 ng/ml) underwent complete IVF/ICSI treatment cycles in the Reproductive Center of the First Affiliated Hospital of Xinjiang Medical University between January 2017 and March 2019. Patients underwent IVF/ICSI treatment using either progestin-primed ovarian stimulation (PPOS) or gonadotrophin-releasing hormone (GnRH) antagonist protocol as ovarian stimulation protocol. RESULTS: Three models were established to analyse the correlation between AMH and the number of utilizable embryos in this study. After adjusting for covariates (age, baseline FSH, stimulation protocol and AFC), the number of embryos increased by 0.1 (95% confidence interval [CI] 0.06-0.14) with each increment of 0.1 ng/ml in AMH concentration. AMH was transformed from a continuous variable to a categorical variable (through trisection of AMH concentrations) and for the sensitivity analysis it was found that the number of embryos in the high AMH group (0.52-1.19 ng/ml) was 0.62 (95% CI 0.37-0.97) higher than in the low AMH group (0.06-0.24 ng/ml). CONCLUSIONS: High AMH in patients in POSEIDON Groups 3 and 4 was found to be associated with an increase in the number of available embryos in IVF/ICSI. The potential reproductive prognosis can be assessed by AMH, to reduce the abandonment of treatment due to underestimation or to implement multiple ineffective stimulation cycles of treatment.


Assuntos
Hormônio Antimülleriano/sangue , Fertilização in vitro/estatística & dados numéricos , Adulto , Feminino , Humanos , Reserva Ovariana , Estudos Retrospectivos
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(9): 2505-9, 2015 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-26669156

RESUMO

Hetao muskmelon is a unique fruit in the hetao area of northwest china, which has been loved by consumers. Sugar content is the important indicator of measuring the quality and mature of muskmelons. This research uses Maya 2000 pro portable spectrometer and PR-101α portable digital refractometer to get spectrum and sugar content values of "jinhongbao" muskmelon, researches the effect of different extraction methods of characteristic wavelength (stepwise multiple linear regression (SMLR), interval partial least squares(iPLS), backward interval partial least squares (biPLS) and synergy interval partial least squares (siPLS)) on model accuracy and prediction results. The results show: using biPLS method on extraction of characteristic wavelength will the full spectrum evenly divided into 20 subintervals, the PLS factors of 14, when removing 8 subintervals, and choosing the wavelength variable numbers of 218, getting the biPLS model is best, RMSE of corresponding calibration and prediction models is 0.9961 and 1.18. So using the biPLS method of extraction on spectrum wavelength could extract effectively the characteristic wavelengths of melon sugar content, increase the ability of model prediction, and achieve rapid detecting of sugar content about muskmelons.


Assuntos
Carboidratos/análise , Cucumis melo/química , Espectroscopia de Luz Próxima ao Infravermelho , Análise dos Mínimos Quadrados , Modelos Lineares
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(11): 2987-91, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23387163

RESUMO

Outlier samples strongly influence the precision of the calibration model in soluble solids content measurement of melons using NIR Spectra. According to the possible sources of outlier samples, three methods (predicted concentration residual test; Chauvenet test; leverage and studentized residual test) were used to discriminate these outliers respectively. Nine suspicious outliers were detected from calibration set which including 85 fruit samples. Considering the 9 suspicious outlier samples maybe contain some no-outlier samples, they were reclaimed to the model one by one to see whether they influence the model and prediction precision or not. In this way, 5 samples which were helpful to the model joined in calibration set again, and a new model was developed with the correlation coefficient (r) 0. 889 and root mean square errors for calibration (RMSEC) 0.6010 Brix. For 35 unknown samples, the root mean square errors prediction (RMSEP) was 0.854 degrees Brix. The performance of this model was more better than that developed with non outlier was eliminated from calibration set (r = 0.797, RMSEC= 0.849 degrees Brix, RMSEP = 1.19 degrees Brix), and more representative and stable with all 9 samples were eliminated from calibration set (r = 0.892, RMSEC = 0.605 degrees Brix, RMSEP = 0.862 degrees).


Assuntos
Cucurbitaceae/química , Modelos Teóricos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Calibragem , Análise Discriminante , Controle de Qualidade
5.
Front Endocrinol (Lausanne) ; 13: 821753, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35586619

RESUMO

Background: In frozen-thawed embryo transfer (FET) cycles, endometrial thickness (EMT) has been used routinely as the main clinical monitoring index. However, the current findings are conflicting. Method: This was a single-center retrospective study of 2,054 couples (2,562 cycles) who underwent FET (including cleavage stage embryos and blastocysts) between January 2017 and August 2020 in the reproductive centers of First Affiliated Hospital of Xinjiang Medical University. The primary outcome measure was the ongoing pregnancy rate (OPR); the secondary outcome was the clinical pregnancy rate. Results: After stratified analysis and adjusting for confounders such as maternal age, duration of infertility, number of high-quality embryos transferred, endometrial preparation protocol, number of transfer cycles, and stages of embryo transferred, we found a curvilinear relationship between EMT and the OPR in women < 35 years of age. For women with EMT ≤ 8 mm, the OPR increased by 150% for cleavage stage embryo transfer for every 1 mm increase in the EMT; similarly, it increased by 97% for blastocyst stage FET. However, there was a linear relationship between EMT and OPR in women aged ≥ 35 years. When blastocysts were transferred, for every 1 mm increase in the EMT the OPR increased significantly by 12%. But OPR after frozen-thawed cleavage stage embryos transfer did not increase significantly with increased EMT. Conclusions: Our study showed that the OPR increased significantly with increased EMT between young women aged < 35 years with EMT ≤ 8 mm and older women who underwent transfer of blastocysts.


Assuntos
Criopreservação , Transferência Embrionária , Adulto , Idoso , Criopreservação/métodos , Transferência Embrionária/métodos , Feminino , Humanos , Idade Materna , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
6.
Bosn J Basic Med Sci ; 21(1): 81-92, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32343942

RESUMO

MiR-145 is reported to facilitate inflammation and is also associated with unsuccessful embryonic implantation. Whether miR-145 mediates inflammatory response underlying hydrosalpinx-induced defective endometrial receptivity (ER) remains unclear, and this study attempted to clarify this point. Endometrium samples were collected from hydrosalpinx patients (case, n = 243) and patients with tubal patency/obstruction (control, n = 187). The peripheral blood samples of cases and controls were collected to determine the genotypes of miR-145 SNPs. The value of miR-145 expression in the diagnosis and prognostic estimation of hydrosalpinx was assessed using ROC curve and regression analysis, respectively. Lipopolysaccharide (LPS) cell model was established with endometrial cells, and cells were transfected with miR-145 mimic, inhibitor, or negative control. MiR-145 and cytokine levels were quantified by quantitative reverse transcription PCR or western blot. MiR-145 expression was significantly higher in hydrosalpinx compared to control group, and high miR-145 expression was significantly associated with moderate/severe tube lesion, high pulsatility index (>1.06), and high resistance index (>0.61) in hydrosalpinx patients. ROC curve analysis indicated that monitoring miR-145 expression may be useful for the diagnosis of hydrosalpinx (AUC = 0.704). A alleles of rs41291957 (G>A) and rs353292 (G>A) were significantly associated with an increased risk of hydrosalpinx compared to G allele (p < 0.05), yet the mutant allele of rs353291 (A>G) and rs4705343 (T>C) significantly reduced susceptibility to hydrosalpinx compared to the wild type allele. Treatments with miR-145 mimic and LPS in endometrial cells significantly increased the levels of transforming growth factor-ß1, tumor necrosis factor -α, interleukin (IL)-6, and IL-8 compared to negative control, while treatment with miR-145 inhibitor decreased the cytokine levels. In conclusion, abnormally expressed miR-145 may be involved in hydrosalpinx-induced ER defects by regulating the inflammatory response.


Assuntos
Endométrio/metabolismo , Endométrio/patologia , Doenças das Tubas Uterinas/genética , MicroRNAs/genética , Adulto , Biomarcadores/metabolismo , Células Cultivadas , Diagnóstico Diferencial , Endométrio/citologia , Doenças das Tubas Uterinas/diagnóstico , Feminino , Genótipo , Haplótipos , Humanos , Polimorfismo de Nucleotídeo Único , Prognóstico
7.
Medicine (Baltimore) ; 99(12): e19464, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32195945

RESUMO

RATIONALE: The aim of this report is to present the technique of selective nerve root blockage combined with posterior percutaneous cervical endoscopic discectomy (PPECD) for cervical spondylotic radiculopathy (CSR). PATIENT CONCERNS: A 49-year-old female has pain in the skin area of the left scapular, pain in left elbow and limitation of left upper limb movement for 1.5 years. DIAGNOSIS: She was diagnosed with CSR and C6-7 double nerve root variation. INTERVENTIONS: We used selective nerve root block to determine the lesion segment and applied PPECD to relieve pressure on the patient's nerve roots. OUTCOMES: The pain symptoms disappeared after the patient was treated with C6-7 nerve root block. Endoscopic displayed C6-7 double nerve root variation on the left side of the spinal cord intraoperative. The neurological function was intact postoperatively and no recurrence of cervical disc herniation during the 5 months' follow-up period. The hospitalization time was 5 days, the operation time was 68.2 minutes and the bleeding volume was 52.6 ml. There was no change in cervical curvature and cervical disc height postoperatively. Japanese Orthopaedic Association score, SF-36 score and Visual Analogue Scale score improved significantly postoperatively. LESSONS: The application of selective nerve root blockage combined with PPECD for CSR could achieve satisfactory effect of position and decompression of the injured nerve root. Besides, we recommend that surgery be performed under general anesthesia to minimize patients' emotional stress and discomfort.


Assuntos
Discotomia/métodos , Pescoço/cirurgia , Bloqueio Nervoso/métodos , Espondilose/tratamento farmacológico , Espondilose/cirurgia , Terapia Combinada , Descompressão Cirúrgica/métodos , Discotomia/instrumentação , Endoscopia/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Pescoço/inervação , Pescoço/patologia , Radiculopatia/fisiopatologia , Espondilose/diagnóstico por imagem , Resultado do Tratamento
8.
Ying Yong Sheng Tai Xue Bao ; 31(6): 1875-1881, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34494739

RESUMO

We investigated the characteristics of nitrogen uptake, distribution, and utilization in the three-year-old bearing Huangguan pear trees following 15N-urea application in early spring. The results showed that the growth of pear trees was mainly depended on vegetative organs such as shoots and leaves at the stage from budbreak to shoot growth arrest, but mainly on storage organs (roots) and supplemented by the formation of fruit yield and quality at the stage from shoot growth arrest stage to fruit harvest. Meanwhile, tree biomass, especially that storage organs, substantially increased. All organs, especially newly developed shoots and leaves, acquired more N in shoot growth arrest stage due to vigorous growth, with relatively higher N derived from fertilizer (Ndff). Ndff of each organ except for root was lower at fruit maturity stage than that at shoot growth stage. Most of the labeled nitrogen was distributed in the newly developed organs (shoots and leaves) from budbreak to shoot growth arrest stage, but in the storage organs during shoot growth arrest stage to fruit maturity stage. Labeled fertilizer nitrogen was mainly distributed in the storage organs, followed by the vegetative organs. Reproductive organs had the lowest allocation in the experimental stage. For the three-years-old pear trees, the ratio of absorbed N from fertilizer was responsible for 31.1% and 21.0% of total absorbed nitrogen from budbreak to shoot growth arrest stage and from shoot growth arrest stage to fruit maturity stage, respectively, with the remaining N (68.9% and 79.0% of total) being absorbed from soil N.


Assuntos
Nitrogênio , Pyrus , Fertilizantes , Árvores , Ureia
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(4): 940-4, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19626877

RESUMO

According to the fact that farmers often picked unripe watermelon and treated them with high concentration ethylene to quicken ripeness, classification experiments on the two classes of watermelon mentioned above were conducted based on the Vis/NIR spectroscopy diffuse transmittance technique. In the discriminant analysis, a method to classify them by diffuse transmittance ration at two wavelengths was adopted to discriminate them. Result of mistake ratio 32.5% for samples without ethylene treatment and 20% for ethylene treatment samples indicated that this method could discriminate the two classes of watermelons roughly. Mahalanobis distance and partial least square methods were also used here for discriminant analysis and satisfied results were obtained. The first derivative spectra with Norris derivative filtering of samples without being ethylene-treated using Mahalanobis distance discriminant analysis got the result of mistake ratio 1.67% for calibration set, no mistake for prediction set and no mistake for samples being ethylene treated. No mistake took place for the second derivative spectra using partial least square method. In discriminant analysis, spectral data pretreatment methods influence the discriminant results and it should be selected according to the analysis methods.


Assuntos
Citrullus/química , Citrullus/efeitos dos fármacos , Etilenos/farmacologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Carboidratos/análise
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(6): 1536-40, 2009 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-19810525

RESUMO

To make Vis/NIR diffuse transmittance technique applied to quality prediction for watermelon in motion, the dynamic spectra detecting system was rebuilt. Spectra detecting experiments were conducted and the effects of noises caused by motion on spectra were analyzed. Then the least--square filtering method and Norris differential filtering method were adopted to eliminate the effects of noise on spectra smoothing, and statistical models between the spectra and soluble solids content were developed using partial least square method. The performance of different models was assessed in terms of correlation coefficients (r) of validation set of samples, root mean square errors of calibration (RMSEC) and root mean square errors of prediction (RMSEP). Calibration and prediction results indicated that Norris differential method was an effective method to smooth spectra and improve calibration and prediction results, especially, with r of 0.895, RMSEC of 0.549, and RMSEP of 0.760 for the calibration and prediction result of the first derivative spectra.


Assuntos
Citrullus/química , Movimento (Física) , Calibragem , Controle de Qualidade , Solubilidade , Espectrofotometria Infravermelho
11.
Medicine (Baltimore) ; 98(29): e16396, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31335689

RESUMO

RATIONALE: Cauda equina syndrome (CES) refers to a group of symptoms that occur when the nerves in the cauda equina become compressed or damaged. The most common etiology of CES is lumbar intervertebral disc herniation, but CES following lumbar spinal surgery is rare, especially without motor dysfunction. Herein, we illustrate a case of CES that developed as a complication of spinal surgery and to deduce its possible underlying cause. PATIENT CONCERNS: A 46-year-old man experienced lumbago, bilateral shank pain, and numbness with neurogenic claudication for 3 years due to degenerative lumbar disc herniation and spinal cord stenosis. After a thorough examination to diagnose lumbar spinal stenosis, the patient underwent bilateral decompression and pedicle screw system internal fixation with bone graft. Postoperatively, the patient showed regained strength in his bilateral shanks, and he did not complain of lumbago and shank pain, but CES occurred, which manifested as underpants-type numbness in the perineum without bladder, anal, and motor dysfunction. DIAGNOSES: CES as a postoperative complication of lumbar stenosis. INTERVENTIONS: The patient underwent bilateral laminectomies, partial facetectomies, and pedicle screw system internal fixation and fusion with bone graft. Postoperatively, the patient performed adequate rehabilitation exercises and was expected to recover spontaneously. OUTCOMES: The symptoms of pain and claudication resolved after 3 weeks in the hospital, but an underpants-type hypoesthesia in the perineum without motor dysfunction developed. The patient experienced full recovery from CES 6 months after surgery. LESSONS: CES as a complication of lumbar spinal surgery is very rare. Excessive sensitivity to the traction of the dural sac was, in our opinion, the most possible cause of postoperative CES in this case. When the nerve root is pulled intraoperatively, it is best not to cross the central line of the spinous process. The plane of the nerve retractor needs to be parallel to the dural sac at the pulling point to reduce the formation of shear force. Most importantly, gentle maneuver is required because sensitivity to the traction of the dural sac varies individually.


Assuntos
Síndrome da Cauda Equina , Laminectomia , Vértebras Lombares/cirurgia , Complicações Pós-Operatórias , Fusão Vertebral , Estenose Espinal , Síndrome da Cauda Equina/diagnóstico , Síndrome da Cauda Equina/etiologia , Síndrome da Cauda Equina/fisiopatologia , Humanos , Degeneração do Disco Intervertebral/complicações , Degeneração do Disco Intervertebral/diagnóstico , Degeneração do Disco Intervertebral/fisiopatologia , Deslocamento do Disco Intervertebral/complicações , Deslocamento do Disco Intervertebral/diagnóstico , Deslocamento do Disco Intervertebral/fisiopatologia , Laminectomia/efeitos adversos , Laminectomia/métodos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos , Estenose Espinal/diagnóstico , Estenose Espinal/etiologia , Estenose Espinal/fisiopatologia , Estenose Espinal/cirurgia , Resultado do Tratamento
12.
Biomed Res Int ; 2019: 6159793, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31346521

RESUMO

OBJECTIVE: The use of cumulative live birth rate (CLBR) per ovarian stimulation cycle is proving to be an accurate method to calculate the success of IVF; however, the cycle outcome is closely associated with the number of embryos transferred (ET). Our aim was to report CLBR after IVF according to the number of embryos required to achieve a live birth in women aged ≥35 years, considering age, body mass index (BMI), and ethnicity. METHODS: We conducted a retrospective cohort study including 1344 patients who underwent IVF between January 2013 and June 2016 at the First Affiliated Hospital of Xinjiang Medical University. The cumulative probability of live birth for each couple was estimated using the Kaplan-Meier method, and survival curves were compared according to age, BMI, and ethnicity using the log-rank test. RESULTS: CLBR increased rapidly from 1 to 5 ETs, moderately from 6 to 10 ETs, and slowly thereafter. CLBR was significantly different across 4 categories based on BMI as well as across those based on age; low CLBR was significantly associated with the age of ≥42 years and obesity. CONCLUSION: The association between CLBR and number of ET provides realistic and precise information regarding the success of IVF and can be applied to guide clinicians and patients.


Assuntos
Transferência Embrionária , Fertilização in vitro , Nascido Vivo , Indução da Ovulação , Adulto , Fatores Etários , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(5): 1062-6, 2008 May.
Artigo em Chinês | MEDLINE | ID: mdl-18720802

RESUMO

The feasibility of Vis/NIR spectroscopy technique for rapid and non-invasive detection of transgenic tomato leaves from conventional ones was investigated by means of spectral diffuse reflectance mode. A total of 68 samples (38 transgenic ones and 30 non-transgenic ones) were used for classification. The calibration and validation results were analyzed via discriminant analysis (DA) and partial least squares (PLS) discriminant method using TQ 6.2. 1 quantitative software. Models based on the different spectral pre-processing methods (multiplicative signal correction (MSC), first and second derivative) were compared. It was found that the classification accuracy using DA was higher than that using PLS and the best results were gained by using spectra after MSC with InGaAs detector and the classification accuracy was 89.7% (accuracy of 86.8% for transgenic samples and 93.3% for non-transgenic ones). The results show that Vis-NIR diffuse reflectance spectroscopy technique is a feasible and fast method for non-invasive detection of transgenic and non-transgenic tomato leaves.


Assuntos
Folhas de Planta/genética , Plantas Geneticamente Modificadas/genética , Solanum lycopersicum/genética , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise dos Mínimos Quadrados
14.
J Zhejiang Univ Sci B ; 8(2): 105-10, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17266185

RESUMO

Watermelon is a popular fruit in the world with soluble solids content (SSC) being one of the major characteristics used for assessing its quality. This study was aimed at obtaining a method for nondestructive SSC detection of watermelons by means of visible/near infrared (Vis/NIR) diffuse transmittance technique. Vis/NIR transmittance spectra of intact watermelons were acquired using a low-cost commercially available spectrometer operating over the range 350~1000 nm. Spectra data were analyzed by two multivariate calibration techniques: partial least squares (PLS) and principal component regression (PCR) methods. Two experiments were designed for two varieties of watermelons [Qilin (QL), Zaochunhongyu (ZC)], which have different skin thickness range and shape dimensions. The influences of different data preprocessing and spectra treatments were also investigated. Performance of different models was assessed in terms of root mean square errors of calibration (RMSEC), root mean square errors of prediction (RMSEP) and correlation coefficient (r) between the predicted and measured parameter values. Results showed that spectra data preprocessing influenced the performance of the calibration models. The first derivative spectra showed the best results with high correlation coefficient of determination [r=0.918 (QL); r=0.954 (ZC)], low RMSEP [0.65 degrees Brix (QL); 0.58 degrees Brix (ZC)], low RMSEC [0.48 degrees Brix (QL); 0.34 degrees Brix (ZC)] and small difference between the RMSEP and the RMSEC by PLS method. The nondestructive Vis/NIR measurements provided good estimates of SSC index of watermelon, and the predicted values were highly correlated with destructively measured values for SSC. The models based on smoothing spectra (Savitzky-Golay filter smoothing method) did not enhance the performance of calibration models obviously. The results indicated the feasibility of Vis/NIR diffuse transmittance spectral analysis for predicting watermelon SSC in a nondestructive way.


Assuntos
Algoritmos , Citrullus/química , Análise de Alimentos/métodos , Frutas/química , Fotometria/métodos , Extratos Vegetais/análise , Espectrofotometria Infravermelho/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solubilidade
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(3): 494-8, 2007 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-17554906

RESUMO

The feasibility of Fourier transform near infrared (FTNIR) spectroscopic technology for rapid quantifying the soluble solids content (SSC) of apple fresh juice was investigated by means of spectral transmittance technique. A total of 60 juice samples were used to develop the calibration models. The relationship between laboratory SSC and FTNIR spectra of apple fresh juices was analyzed via principal component regression (PCR) and partial least squares (PLS) regression method using TQ 6.2.1 quantitative software. Models based on different spectral ranges were compared. Performance of different models was assessed in terms of root mean square errors of prediction (RMSEP) and correlation coefficients (r2) of validation set of samples. The best prediction models had a RMSEP of 0.603 degree Brix and correlation coefficient (r2) of 0.997 for SSC. The results show that FTNIR transmittance technique is a feasible, accurate and fast method for non-invasive estimation of fruit fresh juice soluble solids content.


Assuntos
Bebidas/análise , Malus/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Calibragem , Estudos de Viabilidade , Solubilidade
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(6): 1113-7, 2007 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-17763770

RESUMO

Watermelon is a popular fruit in the world and firmness (FM) is one of the major characteristics used for assessing watermelon quality. The objective of the present research was to study the potential of visible/near Infrared (Vis/NIR) diffuse transmittance spectroscopy as a way for the nondestructive measurement of FM of watermelon. Statistical models between the spectra and FM were developed using partial least square (PLS) and principle component regression (PCR) methods. Performance of different models was assessed in terms of correlation coefficients (r) of validation set of samples and root mean square errors of prediction (RMSEP). Models for three kinds of mathematical treatments of spectra (original, first derivative and second derivative) were established. Savitsky-Goaly filter smoothing method was used for spectra data smoothing. The PLS model of the second derivative spectra gave the best prediction of FM, with a correlation coefficient (r) of 0. 974 and root mean square errors of prediction (RMSEP) of 0. 589 N using Savitsky-Goaly filter smoothing method. The results of this study indicate that NIR diffuse transmittance spectroscopy can be used to predict the FM of watermelon. The Vis/NIR diffuse transmittance technique will be valuable for the nandestructive detection large shape and thick peel fruits'.


Assuntos
Citrullus/química , Frutas/química , Espectrofotometria/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Algoritmos , Calibragem , Frutas/normas , Análise dos Mínimos Quadrados , Modelos Estatísticos , Análise de Componente Principal , Análise de Regressão , Espectrofotometria/instrumentação , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação
17.
J Zhejiang Univ Sci B ; 7(10): 794-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16972321

RESUMO

Nondestructive method of measuring soluble solids content (SSC) of citrus fruits was developed using Fourier transform near infrared reflectance (FT-NIR) measurements collected through optics fiber. The models describing the relationship between SSC and the NIR spectra of citrus fruits were developed and evaluated. Different spectra correction algorithms (standard normal variate (SNV), multiplicative signal correction (MSC)) were used in this study. The relationship between laboratory SSC and FT-NIR spectra of citrus fruits was analyzed via principle component regression (PCR) and partial least squares (PLS) regression method. Models based on the different spectral ranges were compared in this research. The first derivative and second derivative were applied to all spectra to reduce the effects of sample size, light scattering, instrument noise, etc. Different baseline correction methods were applied to improve the spectral data quality. Among them the second derivative method after baseline correction produced best noise removing capability and yielded optimal calibration models. A total of 170 NIR spectra were acquired; 135 NIR spectra were used to develop the calibration model; the remaining spectra were used to validate the model. The developed PLS model describing the relationship between SSC and NIR reflectance spectra could predict SSC of 35 samples with correlation coefficient of 0.995 and RMSEP of 0.79 degrees Brix.


Assuntos
Bioquímica/métodos , Citrus/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Calibragem , Análise dos Mínimos Quadrados , Luz , Modelos Estatísticos , Análise de Regressão , Reprodutibilidade dos Testes , Espalhamento de Radiação , Espectroscopia de Luz Próxima ao Infravermelho
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