A new canthinone glycoside isolated from the root barks of Ailanthus altissima with NO inhibitory activity.

One new canthinone glycoside (1), together with six known compounds (2-7) including three lignans (2-4), two coumarins (5-6) and one phenol (7) was isolated from the root barks of Ailanthus altissima. The structure of new compound 1 was established by the interpretation of UV, IR, MS and NMR data, while its absolute configuration was determined by acid hydrolysis and GIAO NMR calculations with DP4+ probability analysis. The inhibitory effects of all compounds on Nitric oxide (NO) production were investigated in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Results showed that compounds 2 and 5 displayed NO production inhibitory activity with IC50 values of 30.1 and 15.3 µM, respectively.

ALDEFLUOR activity, ALDH isoforms, and their clinical significance in cancers.

High aldehyde dehydrogenase (ALDH) activity is a metabolic feature of adult stem cells and various cancer stem cells (CSCs). The ALDEFLUOR system is currently the most commonly used method for evaluating ALDH enzyme activity in viable cells. This system is applied extensively in the isolation of normal stem cells and CSCs from heterogeneous cell populations. For many years, ALDH1A1 has been considered the most important subtype among the 19 ALDH family members in determining ALDEFLUOR activity. However, in recent years, studies of many types of normal and tumour tissues have demonstrated that other ALDH subtypes can also significantly influence ALDEFLUOR activity. In this article, we briefly review the relationships between various members of the ALDH family and ALDEFLUOR activity. The clinical significance of these ALDH isoforms in different cancers and possible directions for future studies are also summarised.

Two new guaianolide-type sesquiterpenoids with NO inhibitory activity from Chrysanthemum indicum.

Two new guaianolide-type sesquiterpenoids chrysanthemulides K and L (1 and 2), together with six known analogues (3-8), were isolated from an CH2Cl2 extract of the aerial parts of Chrysanthemum indicum. The structures of new compounds 1 and 2 were established by extensive spectroscopic analysis, including UV, IR, MS, NMR and computational electronic circular dichroism (ECD) methods. Inhibitory effects of all compounds on nitric oxide production were investigated in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Results showed that compounds 1-8 displayed NO production inhibitory activity with IC50 values ranged from 3.5 to 34.3 µM.

Design, Synthesis and Bioactivity Evaluation of Heterocycle-Containing Mono- and Bisphosphonic Acid Compounds.

Fosmidomycin (FOS) is a naturally occurring compound active against the 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR) enzyme in the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway, and using it as a template for lead structure design is an effective strategy to develop new active compounds. In this work, by replacing the hydroxamate unit of FOS with pyrazole, isoxazole and the related heterocycles that also have metal ion binding affinity, while retaining the monophosphonic acid in FOS or replacing it with a bisphosphonic acid group, heterocycle-containing mono- and bisphosphonic acid compounds as FOS analogs were designed. The key steps involved in the facile synthesis of these FOS analogs included the Michael addition of diethyl vinylphosphonate or tetraethyl vinylidenebisphosphonate to ß-dicarbonyl compounds and the subsequent cyclic condensation with hydrazine or hydroxylamine. Two additional isoxazolinone-bearing FOS analogs were synthesized via the Michaelis-Becker reaction with diethyl phosphite as a key step. The bioactivity evaluation on model plants demonstrated that several compounds have better herbicidal activities compared to FOS, with the most active compound showing a 3.7-fold inhibitory activity on Arabidopsis thaliana, while on the roots and stalks of Brassica napus L. and Echinochloa crus-galli in a pre-emergence inhibitory activity test, the activities of this compound were found to be 3.2- and 14.3-fold and 5.4- and 9.4-fold, respectively, and in a post-emergency activity test on Amaranthus retroflexus and Echinochloa crus-galli, 2.2- and 2.0-fold inhibition activities were displayed. Despite the significant herbicidal activity, this compound exhibited a DXR inhibitory activity lower than that of FOS but comparable to that of other non-hydroxamate DXR inhibitors, and the dimethylallyl pyrophosphate rescue assay gave no statistical significance, suggesting that a different target might be involved in the inhibiting process. This work demonstrates that using bioisosteric replacement can be considered as a valuable strategy to discover new FOS analogs that may have high herbicidal activities.

Secondary crest myofibroblast PDGFRα controls the elastogenesis pathway via a secondary tier of signaling networks during alveologenesis.

Postnatal alveolar formation is the most important and the least understood phase of lung development. Alveolar pathologies are prominent in neonatal and adult lung diseases. The mechanisms of alveologenesis remain largely unknown. We inactivated Pdgfra postnatally in secondary crest myofibroblasts (SCMF), a subpopulation of lung mesenchymal cells. Lack of Pdgfra arrested alveologenesis akin to bronchopulmonary dysplasia (BPD), a neonatal chronic lung disease. The transcriptome of mutant SCMF revealed 1808 altered genes encoding transcription factors, signaling and extracellular matrix molecules. Elastin mRNA was reduced, and its distribution was abnormal. Absence of Pdgfra disrupted expression of elastogenic genes, including members of the Lox, Fbn and Fbln families. Expression of EGF family members increased when Tgfb1 was repressed in mouse. Similar, but not identical, results were found in human BPD lung samples. In vitro, blocking PDGF signaling decreased elastogenic gene expression associated with increased Egf and decreased Tgfb family mRNAs. The effect was reversible by inhibiting EGF or activating TGFß signaling. These observations demonstrate the previously unappreciated postnatal role of PDGFA/PDGFRα in controlling elastogenic gene expression via a secondary tier of signaling networks composed of EGF and TGFß.

Triple-negative breast cancer molecular subtyping and treatment progress.

Triple-negative breast cancer (TNBC), a specific subtype of breast cancer that does not express estrogen receptor (ER), progesterone receptor (PR), or human epidermal growth factor receptor 2 (HER-2), has clinical features that include high invasiveness, high metastatic potential, proneness to relapse, and poor prognosis. Because TNBC tumors lack ER, PR, and HER2 expression, they are not sensitive to endocrine therapy or HER2 treatment, and standardized TNBC treatment regimens are still lacking. Therefore, development of new TNBC treatment strategies has become an urgent clinical need. By summarizing existing treatment regimens, therapeutic drugs, and their efficacy for different TNBC subtypes and reviewing some new preclinical studies and targeted treatment regimens for TNBC, this paper aims to provide new ideas for TNBC treatment.

Remodeling of myocardial energy and metabolic homeostasis in a sheep model of persistent atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) is the most common progressive cardiac arrhythmia and is often associated with rapid contraction in both atria and ventricles. The role of atrial energy and metabolic homeostasis in AF progression is under-investigated. OBJECTIVES: To determine the remodeling of energy metabolism during persistent AF and the effect of eplerenone (EPL), an aldosterone inhibitor, on metabolic homeostasis. METHODS: A nonsustained atrial pacing sheep model was developed to simulate the progression of AF from paroxysmal to persistent. Metabolomic and proteomic analyses at termination of the experiment were used to analyze atrial tissues obtained from sheep in sham, sugar pill (SP) and EPL-treated groups. RESULTS: Proteomic analysis indicated that compared to the sham group, in SP group, fatty acid (FA) synthesis, FA oxidation, tricarboxylic acid (TCA) cycle processes and amino acids (AAs) transport and metabolism were reduced, while glycolytic processes were increased. In metabolomic analysis, the levels of intermediate metabolites of the glycolytic pathways, including 2-phosphoglyceric acid (2 PG), 1,3-bisphosphoglyceric acid (1,3 PG), and pyruvate, HBP (uridine diphosphate-N-acetylglucosamine, UDP-GlcNAc), TCA (citrate) and AAs were greater while the levels of the majority of lipid classes, including phosphatidic acid (PA), phosphatidylcholine (PC), phosphatidylglycerol (PG), glycerophosphoglycerophosphates (PGP), glycerophosphoinositols (PI) and glycerophosphoserines (PS), were decreased in the atria of SP group than in those of sham group. EPL-pretreatment decreased the expression of glut4 and increased the content of acylcarnitines and lipids, such as lyso phospholipids, phospholipids and neutral lipids. CONCLUSION: In the metabolic remodeling during AF, glucose and lipid metabolism were up- and down-regulated, respectively, to sustain TCA cycle anaplerosis. EPL partialy reversed the metabolic shifting.

Development of EST-derived microsatellite markers to investigate the population structure of sparganum - the causative agent of zoonotic sparganosis.

The plerocercoid (sparganum) of Spirometra erinaceieuropaei is the main aetiological agent of human sparganosis. To improve the current knowledge on S. erinaceieuropaei evolution, we performed multi-locus microsatellite typing of sparganum isolates from China for the first time. All available expressed sequence tag (EST) sequences for the Spirometra were downloaded from the GenBank. The identification and localization of microsatellites in ESTs was accomplished by MISA. Based on the selected microsatellites, the genetic structure of 64 sparganum isolates collected from 11 geographical locations in southwest China were investigated through principal component analysis, STRUCTURE analysis and neighbour-joining clustering. A total of 522 non-redundant ESTs containing 915 simple sequence repeats were identified from 12 481 ESTs screened. Five primer pairs were finally selected. Using these loci, a total of 12 alleles were detected in 64 sparganum isolates. Little variability was observed within each of geographical population, especially among isolates derived from Kunming of Yunnan (YN-KM) province. Both STRUCTURE analysis and the clustering analysis supported that two genotypes existed among the sparganum isolates from southwest China. In conclusion, five microsatellite markers were successfully developed, and sparganum population was observed to harbour low genetic variation, further investigation with deeper sampling was needed to elucidate the population structure.

[A clinical study of growth and metabolism of small for gestational age infants].

OBJECTIVE: To study the differences in growth and metabolism between small for gestational age (SGA) infants and appropriate for gestational age (AGA) infants. METHODS: A total of 1 370 preterm infants were enrolled in this study. According to the association between gestational age and birth weight, they were divided into SGA group with 675 infants and AGA group with 695 infants. The two groups were compared in terms of general conditions, physical growth and blood biochemical parameters. RESULTS: The SGA group had a significantly longer length of hospital stay than the AGA group (P<0.05). Compared with the AGA group, the SGA group had significantly lower body weight, body weight Z score, and body length at discharge and significantly higher incidence rate of extrauterine growth retardation and growth rate of head circumference (P<0.05). Compared with the AGA group, the SGA group had significantly longer time to full enteral nutrition and duration of parenteral nutrition (P<0.05). Compared with the AGA group, the SGA group had significantly higher levels of albumin, prealbumin, and serum phosphorus on admission and total bile acid before discharge, as well as a significantly lower albumin level before discharge (P<0.05). The incidence rates of asphyxia, neonatal respiratory distress syndrome, myocardial damage, feeding intolerance, pneumonia, sepsis, hypoglycemia and hypothyroxinemia in the SGA group were significantly higher than in the AGA group (P<0.05). CONCLUSIONS: Compared with AGA infants, SGA infants have significantly delayed physical development during hospitalization and significantly higher incidence rates of extrauterine growth retardation and related complications.

[Levels of blood free carnitine in preterm infants with different gestational ages and birth weights].

OBJECTIVE: To examine blood concentrations of free carnitine (FC) in preterm infants with different gestational ages (GA) and birth weights (BW). METHODS: A total of 3 368 preterm infants were enrolled as subjects. According to GA, they were divided into extremely preterm birth (EPTB) group (GA <28 weeks; n=39), very preterm birth (VPTB) group (28 ≤GA <32 weeks; n=405), moderately preterm birth (MPTB) group (32 ≤GA <34 weeks; n=507), and late preterm birth (LPTB) group (34 ≤GA <37 weeks; n=2 417); according to BW, they were divided into extremely low birth weight (ELBW) group (BW <1 000 g; n=36), very low birth weight (VLBW) group (1 000 g ≤BW <1 500 g; n=387), low birth weight (LBW) group (1 500 g ≤BW <2 500 g; n=1 873), and normal birth weight (NBW) group (2 500 g ≤ BW <4 000 g; n=1 072). Blood concentrations of FC were measured between 72 hours and 7 days after birth. RESULTS: The EPTB and VPTB groups had significantly higher FC concentrations than the MPTB and LPTB groups (P<0.05), and the MPTB group had significantly higher FC concentrations than the LPTB group (P<0.05). The lower limit of the 95% medical reference range of FC increased with the reduction in GA. The ELBW and VLBW groups had significantly higher FC concentrations than the LBW and NBW groups (P<0.05). The LBW group had significantly higher FC concentrations than the NBW group (P<0.05). The lower limit of the 95% medical reference range of FC increased with the reduction in BW. CONCLUSIONS: There is a significant increase in blood FC concentrations in very/extremely preterm infants and very/extremely low birth weight infants, and tend to decrease with the increases in GA and BW.

[Clinical application of whole exome sequencing in monogenic hereditary disorders in critically ill newborns].

OBJECTIVE: To explore the value and significance of the clinical application of whole exome sequencing (WES) in monogenic hereditary disorders in critically ill newborns. METHODS: The critically ill newborns in the neonatal intensive care unit with suspected hereditary diseases or unclear clinical diagnosis from June 2016 to December 2018 were enrolled. The whole blood samples from both newborns and parents were collected for WES. The detected genetic mutations were classified, the mutations associated with clinical phenotypes were searched for, and Sanger sequencing was performed to verify the mutations. RESULTS: A total of 45 newborns were enrolled, including 22 males and 23 females, and the median age of onset was 2.0 days. Of the 45 newborns, 12 (27%) were confirmed with monogenic hereditary disorders by molecular diagnostics, and the median age at diagnosis was 31.5 days. Of the 12 newborns with monogenic hereditary disorders, 5 (42%) were partially associated with clinical phenotypes but confirmed with monogenic hereditary disorders by additional information supplement and analysis. The improvement rate of newborns with monogenic hereditary disorders was 67% (8/12) after treatment. CONCLUSIONS: WES technology is a powerful tool for finding genetic mutations in monogenic hereditary disorders in critically ill newborns and can play a crucial role in clinical decision-making. However, a comprehensive interpretation of sequence data requires physicians to take the clinical phenotypes and the results of WES into consideration simultaneously.

Connexin 43 C-terminus directly inhibits the hyperphosphorylation of Akt/ERK through protein-protein interactions in glioblastoma.

Although the deregulation of epidermal growth factor receptor (EGFR) is one of the most common molecular mechanisms of glioblastoma (GBM) pathogenesis, the efficacy of anti-EGFR therapy is limited. Additionally, response to anti-EGFR therapy is not solely dependent on EGFR expression and is more promising in patients with reduced activity of EGFR downstream signaling pathways. Thus, there is considerable interest in identifying the compensatory regulatory factors of the EGFR signaling pathway to improve the efficacy of anti-EGFR therapies for GBM. In this study, we confirmed the low efficacy of EGFR inhibitors in GBM patients by meta-analysis. We then identified a negative correlation between connexin 43 (Cx43) expression and Akt/ERK activation, which was caused by the direct interactions between Akt/ERK and Cx43. By comparing the interactions between Akt/ERK and Cx43 using a series of truncated and mutated Cx43 variants, we revealed that the residues T286/A305/Q308/Y313 and S272/S273 at the carboxy terminus of Cx43 are critical for its binding with Akt and ERK, respectively. In addition, Kaplan-Meier survival analysis using data from The Cancer Genome Atlas datasets indicated that the expression of Cx43 significantly improved the prognosis of GBM patients who express EGFR. Together, our results suggested that Cx43 acts as an inhibitory regulator of the activation of growth factor receptor downstream signaling pathways, indicating the potential of Cx43 as a marker for predicting the efficacy of EGFR inhibitor treatments for GBM. Targeting the interaction between the carboxy terminus of Cx43 and Akt/ERK could be an effective therapeutic strategy against GBM.

[Effect of prone positioning on respiratory function in very preterm infants undergoing mechanical ventilation].

OBJECTIVE: To explore the effect of prone positioning on respiratory function in very preterm infants undergoing mechanical ventilation. METHODS: A total of 83 very preterm infants treated with mechanical ventilation were enrolled in the study and were randomly assigned to supine group and prone group. Four infants withdrew from the study and 79 infants completed treatment and observation (37 in the supine group and 42 in the prone group). Infants in both groups were mechanically ventilated in a volume assist-control mode. Infants in the prone group were ventilated in the supine position for 4 hours and in the prone position for 2 hours. Ventilator parameters, arterial blood gas analysis, and vital signs were recorded before grouping, every 6 hours in the supine group, and every hour after conversion into the prone position in the prone group, respectively. RESULTS: Fraction of inspired oxygen (FiO2), peak inspiratory pressure, mean inspiratory pressure, and duration of ventilation were significantly lower in the prone group than in the supine group (P<0.05); there were no significant differences in tidal volume or positive end-expiratory pressure between the two groups (P>0.05). The prone group had a significantly higher PO2/FiO2 ratio but significantly lower oxygenation index and respiratory rate than the supine group (P<0.05). There were no significant differences in arterial oxygen tension, pH, base excess, heart rate, or mean blood pressure between the two groups (P>0.05). CONCLUSIONS: Alternating ventilation between the prone position and supine position can improve oxygenation function, decrease the fraction of inspired oxygen, and shorten the duration of mechanical ventilation in very preterm infants undergoing mechanical ventilation.

Comparative mitochondrial genomics among Spirometra (Cestoda: Diphyllobothriidae) and the molecular phylogeny of related tapeworms.

The larva of Spirometra erinaceieuropaei can parasitize humans, causing a serious parasitic zoonosis known as sparganosis. Although it is medically important, our knowledge about the phylogenetic position of S. erinaceieuropaei and its evolutionary history is fragmentary. In this study, complete mitochondrial (mt) genomes of 4 geographically distinct isolates of S. erinaceieuropaei spargana collected from 4 frog hosts (Hylarana guentheri, Rana nigromaculata, R. rugulosa, R. temporaria) were characterized using an Illumina sequencing platform. In addition, all available mt genomes of Cestoda in GenBank were included to reconstruct the phylogeny and to explore the evolutionary history of these tapeworms. The genome features of S. erinaceieuropaei contained 12 protein-coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes and 2 non-coding regions. Nucleotide sequences of mtDNA from different frog hosts were similar. Three genes, cox1, cytb and nad4, had high levels of nucleotide diversity. Phylogenetic analyses supported the sibling relationship between Bothriocephalidae and Diphyllobothriidae. Molecular dating analysis indicated that the divergence between Diphyllobothrium and Diplogonoporus started in the late Miocene. The mt genomes of S. erinaceieuropaei will serve as a useful dataset for studying the genetics and systematics of the species of Spirometra genus in particular and diphyllobothriid tapeworms in general.

Using the small subunit of nuclear ribosomal DNA to reveal the phylogenetic position of the plerocercoid larvae of Spirometra tapeworms.

Although medically important, the systematics of Spirometra and the taxonomic position of S. erinaceieuropaei remain unclear. In this study, the 18S rDNA gene of S. erinaceieuropaei sparganum from naturally infected frogs caught in 14 geographical locations of China was sequenced. In addition, all available 18S sequences of the family Diphyllobothriidae in the Genbank database were included to reconstruct the phylogeny of diphyllobothriid tapeworms. The secondary structure model of the 18S rDNA was also predicated to further explore the sequence variation. Phylogenetic analyses were performed using maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI) methods. The intraspecific divergences of 18S rDNA in Chinese sparganum isolates ranged from 0.0 to 0.4%. Regions of V2, V4 and V7 were the most variable regions in the secondary structure of 18S rDNA. With the exception of genera Duthiersia and Probothriocephalus, other genera (i.e., Adenocephalus, Diphyllobothrium, Diplogonoporus, Duthiersia, Schistocephalus and Spirometra) selected in the Diphyllobothriidae shared similar topologies of V2, V4 and V7 structures. The topology of generated phylogenetic trees revealed close relationships among Adenocephalus, Digramma, Diphyllobothrium, Diplogonoporus, Ligula, Sparganum and Spirometra. The exact phylogenetic position of Spirometra species should be further analyzed with more sampling and more useful molecular markers.

ALDH1A3, a metabolic target for cancer diagnosis and therapy.

Metabolism reprogramming has been linked with the initiation, metastasis, and recurrence of cancer. The aldehyde dehydrogenase (ALDH) family is the most important enzyme system for aldehyde metabolism. The human ALDH family is composed of 19 members. ALDH1A3 participates in various physiological processes in human cells by oxidizing all-trans-retinal to retinoic acid. ALDH1A3 expression is regulated by many factors, and it is associated with the development, progression, and prognosis of cancers. In addition, ALDH1A3 influences a diverse range of biological characteristics within cancer stem cells and can act as a marker for these cells. Thus, growing evidence indicates that ALDH1A3 has the potential to be used as a target for cancer diagnosis and therapy.

Statistical colour models: an automated digital image analysis method for quantification of histological biomarkers.

BACKGROUND: Colour is the most important feature used in quantitative immunohistochemistry (IHC) image analysis; IHC is used to provide information relating to aetiology and to confirm malignancy. METHODS: Statistical modelling is a technique widely used for colour detection in computer vision. We have developed a statistical model of colour detection applicable to detection of stain colour in digital IHC images. Model was first trained by massive colour pixels collected semi-automatically. To speed up the training and detection processes, we removed luminance channel, Y channel of YCbCr colour space and chose 128 histogram bins which is the optimal number. A maximum likelihood classifier is used to classify pixels in digital slides into positively or negatively stained pixels automatically. The model-based tool was developed within ImageJ to quantify targets identified using IHC and histochemistry. RESULTS: The purpose of evaluation was to compare the computer model with human evaluation. Several large datasets were prepared and obtained from human oesophageal cancer, colon cancer and liver cirrhosis with different colour stains. Experimental results have demonstrated the model-based tool achieves more accurate results than colour deconvolution and CMYK model in the detection of brown colour, and is comparable to colour deconvolution in the detection of pink colour. We have also demostrated the proposed model has little inter-dataset variations. CONCLUSIONS: A robust and effective statistical model is introduced in this paper. The model-based interactive tool in ImageJ, which can create a visual representation of the statistical model and detect a specified colour automatically, is easy to use and available freely at http://rsb.info.nih.gov/ij/plugins/ihc-toolbox/index.html . Testing to the tool by different users showed only minor inter-observer variations in results.

Screening and characterization of early diagnostic antigens in excretory-secretory proteins from Trichinella spiralis intestinal infective larvae by immunoproteomics.

The excretory-secretory (ES) antigens from Trichinella spiralis muscle larvae are the most commonly used diagnostic antigens for trichinellosis, but specific IgG antibodies were not detected in early stage of infection. The aim of this study was to identify early diagnostic antigens from ES proteins of intestinal infective larvae (IIL), the first invasive stage of T. spiralis. Six bands (92, 52, 45, 35, 32, and 29 kDa) of IIL ES proteins were recognized by infection sera in Western blotting as early as 10 days post infection. Total of 54 T. spiralis proteins in six bands were identified by shotgun LC-MS/MS, 30 proteins were annotated, and 27 had hydrolase activity. Several proteins (serine protease, putative trypsin, deoxyribonuclease II family protein, etc.) could be considered as the potential early diagnostic antigens for trichinellosis. Our study provides new insights for screening early diagnostic antigens from intestinal worms of T. spiralis.

Survey of Trichinella infection from domestic pigs in the historical endemic areas of Henan province, central China.

The aim of this work was to investigate the current situation of Trichinella infection from domestic pigs in the historical endemic areas of Henan province, central China. A total of 823 diaphragm samples from the indoor-raised pigs were collected in five cities of Henan during 2014-2015 and examined by artificial digestion method. The overall prevalence of Trichinella infection in pigs was 0.61 % (5/823). Trichinella larvae were detected in 0.91 % (5/550) of pigs from Nanyang city of Henan. The larval burden in infected animals was 0.03 larvae per gram (lpg) of muscles with a range from 0.02 to 0.05 lpg. The larvae were identified as Trichinella spiralis by multiple PCR. Our study confirms the existence of swine trichinellosis in Henan, but the infection level was under the minimum level for defining infectious sources for humans. However, the prevalence of swine Trichinella infection in Henan need to be further evaluated with a large scale of pork samples for ensuring meat food safety.

The Spectral Prediction of Original Primary Pigment Based on Constrained Non-Negative Matrix Factorization.

With direct prediction in the spectral reflectance space with principal component analysis, the numbers of eigenvectors will surpass the numbers of real primary pigments while the eigenvectors and the corresponding coefficients have negative value, which can not directly presented original primary pigment spectral characteristics and corresponding concentration. We proposed an innovative spectral prediction method in which a complete linear spectral space was created according to optical properties of originals pigment. A constrained non-negative matrix factorization algorithm to predict the numbers and spectral curve shapes of real primary pigments was used in the space. So, this paper designed an overall research plan and implementation process about spectral prediction method firstly, and studied how to select and establish a spectral linear space which was conformed to optical properties of originals; taking transparent pigments as example, and spectra constrained non-negative matrix factorization (SCNMF) algorithm was established to predict primary pigment spectra based on basic non-negative matrix factorization algorithm (BNMF). Aiming at realizing multiple optimal solution of BNMF and improving the prediction accuracy as well as make the matrix decomposition results to be clearly physically meaningful; the proposed SCNMF needs to satisfy four constraints: non negative constraint, additive constraint, smoothness constraint and sparseness constraint. The objective function and iterative algorithm to meet four constraints were set up. The prediction results show that the proposed method can realize accurate prediction of original primary pigments' numbers and spectra effectively.