Effect of electroacupuncture of "Jiaji" (EX-B2) on NOD-like receptor protein 3 mediated pyroptosis in spinal cord tissue of rats with acute spinal cord injury. / å¤¹è„Šç”µé’ˆå¯¹æ€¥æ€§è„Šé«“æŸä¼¤å¤§é¼ è„Šé«“ç»„ç»‡NODæ ·å—ä½“çƒ­è›‹ç™½ç»“æž„åŸŸç›¸å ³è›‹ç™½3介导的细胞焦亡的影响.

OBJECTIVES: To observe the effect of electroacupuncture (EA) stimulation of "Jiaji"(EX-B2) on motor function, histomorphology, and expression of NOD-like receptor protein 3 (NLRP3) and N-terminal domain of gasdermin D (GSDMD-N) in the spinal cord tissue of rats with spinal cord injury (SCI), so as to explore its mechanism underlying improvement of SCI. METHODS: Forty eight female SD rats were randomly divided into sham surgery (sham), SCI model (model), EA, and NLRP3 agonist (monosodium urate, MSU) combined with Jiaji EA (MSU+EA) groups, with 12 rats in each group which were further divided into 3 d and 7 d subgroups, with 6 rats at each time point. Two EA groups received EA stimulation of EX-B2 with a frequency of 100 Hz, electrical current of 1-2 mA for 30 min, once a day for 3 or 7 days. After 5 min, 6 h, and 24 h of modeling, rats of the MSU+EA group received intraperitoneal injection of MSU (200 µg/kg, 200 µg/mL) . The motor function was evaluated using Basso-Beattie-Bresnahan (BBB) scale, the morphological structure of rat spinal cord tissue was observed by H.E. staining. The expression of pyroptosis related factors NLRP3, cleaved Caspase-1 and GSDMD-N of the spinal cord was observed by using immunohistochemistry and Western blot separately, the expression and localization of Iba-1 and GSDMD-N in the spinal cord tissue were observed using immunofluorescence double staining method. RESULTS: Compared with the sham group, the BBB scores after modeling and on day 3 and 7 were decreased (P<0.05), while the average OD values (immunoactivity) and expression levels of NLRP3, cleaved Caspase-1 and GSDMD-N proteins, and the immunofluorescence intensity of Iba-1/GSDMD-N (co-expression) of the spinal cord tissues on day 3 and 7 were significantly increased in the model group (P<0.05). In comparison with the model group, the BBB scores on day 3 and 7 were obviously increased (P<0.05), while the immunoactivity and expression levels of NLRP3, cleaved Caspase-1 and GSDMD proteins, and the immunofluorescence intensity of Iba-1/GSDMD-N on day 3 and 7 significantly down-regulated in the EA group (P<0.05) but not in the MSU+EA group (P>0.05), suggesting an elimination of the effects of EA after administration of NLRP3 agonist (MSU). H.E. staining showed obvious bleeding area in the spinal cord tissue, loose tissue and inflammatory cell infiltration on day 3 after modeling, and basic absorption of the bleeding, loose tissue, obvious vacuolar changes of the white matter area, loss and contraction of neurons with infiltration of a large number of inflammatory cells, which was milder in the EA group but not in the MSU+EA group. CONCLUSIONS: EA of EX-B2 can improve the motor function of SCI rats, which may be related to its functions in inhibiting pyroptosis of microglia mediated by NLRP3/Caspase-1 signaling pathway.

[Research progress of acupuncture-moxibustion in treatment of spinal cord injury through mediating inflammatory reaction].

Inflammatory reaction after spinal cord injury (SCI) is the main obstacle to the recovery of neural function. In the occurrence and development of SCI, the complex regulatory mechanisms are involved in inflammatory reaction, including the activation of inflammatory cells (e.g.macrophages and microglia), and the release of cytokines (e.g. tumor necrosis factor, interleukin and chemokines). Acupuncture-moxibustion is significantly effective in clinical treatment of SCI, and its mechanism is related to adjusting the function of inflammatory cells after SCI, modulating the expression of cytokines and the activation of NLRP3 inflammatory bodies, as well as the expression of high mobility group protein B1 and calcitonin gene related peptide. This article summarizes the research progress of mechanism of inflammatory reaction after SCI and the effects of acupuncture-moxibustion intervention in recent years so that the new ideas can be provided to clarify the pathogenesis of SCI and the effect of acupuncture-moxibustion intervention.

Site-directed mutagenesis identified the key active site residues of 2,3-oxidosqualene cyclase HcOSC6 responsible for cucurbitacins biosynthesis in Hemsleya chinensis.

Hemsleya chinensis is a Chinese traditional medicinal plant, containing cucurbitacin IIa (CuIIa) and cucurbitacin IIb (CuIIb), both of which have a wide range of pharmacological effects, including antiallergic, anti-inflammatory, and anticancer properties. However, few studies have been explored on the key enzymes that are involved in cucurbitacins biosynthesis in H. chinensis. Oxidosqualene cyclase (OSC) is a vital enzyme for cyclizing 2,3-oxidosqualene and its analogues. Here, a gene encoding the oxidosqualene cyclase of H. chinensis (HcOSC6), catalyzing to produce cucurbitadienol, was used as a template of mutagenesis. With the assistance of AlphaFold2 and molecular docking, we have proposed for the first time to our knowledge the 3D structure of HcOSC6 and its binding features to 2,3-oxidosqualene. Mutagenesis experiments on HcOSC6 generated seventeen different single-point mutants, showing that single-residue changes could affect its activity. Three key amino acid residues of HcOSC6, E246, M261 and D490, were identified as a prominent role in controlling cyclization ability. Our findings not only comprehensively characterize three key residues that are potentially useful for producing cucurbitacins, but also provide insights into the significant role they could play in metabolic engineering.

The discovery of potentially active diterpenoids to inhibit the pyroptosis from Callicarpa arborea.

Pyroptosis is a programmed-inflammatory cell death, which leads to release of inflammatory cellular contents and formation of inflammation. Uncontrollable pyroptosis can result in serious immune diseases, such as cytokine release syndrome (CRS), sepsis, disseminated intravascular coagulation (DIC), and acute organ damage, including acute respiratory distress syndrome (ARDS) and acute kidney injury (AKI). Members of the Callicarpa genus are significant raw materials for traditional Chinese medicine, widely used for analgesia, hemostasis, and anti-inflammation. Previously, we have reported some ent-clerodane diterpenoids from Callicarpa arborea, shown potent inhibitory effects against pyroptosis. In this study, we went on investigating this kind of diterpenoids, and yielded 66 ent-clerodane diterpenoids, including 52 new compounds, from Callicarpa arborea. Their structures featured with a 5/6- (1-25) or a 6/6- (26-66)-fused double-ring scaffolds, were elucidated using spectroscopic data, electrostatic circular dichroism (ECD) and X-ray diffraction analyses. Screening for the inhibitory activity against pyroptosis by detecting of IL-1ß secretion in J771A.1 cells, revealed 28 compounds with an IC50 below 10.5 µM. Compound 1 was the most potent with an IC50 of 0.68 µM and inhibited the J774A.1 macrophage pyroptosis by blocking the NLR pyrin domain containing 3 (NLRP3) inflammasome activation. An in vivo study further revealed that compound 1 decreased infiltration of CD11b + F4/80 + macrophages into lung and attenuated the lipopolysaccharide (LPS)-induced lung injury. Taken together, this study indicated the potential of compound 1 as a candidate for pyroptosis-related inflammation treatment, as well as provided the chemical and pharmacological basis for the further development of Callicarpa genus as a herbal medicine.

Physiological integration between Bermudagrass ramets improves overall salt resistance under heterogeneous salt stress.

Connected ramets of colonal plants often suffer from different environmental conditions such as light, nutrient, and stress. Colonal Bermudagrass (Cynodon dactylon [L.] Pers.) can form interconnected ramets and this connection facilitates the tolerance to abiotic stress, which is a kind of physiological integration. However, how bermudagrass responds to heterogeneously distributed salt stress needs to be further elucidated. Here, we demonstrated that severance of stolons aggravated the damage of salt-stressed ramets, displaying higher relative electrolytic leakage (EL), lower content of chlorophyll, higher accumulation of Na+ , and serious oxidative damages. This finding implied the positive effects of the physiological integration of bermudagrass on salt tolerance. The unstressed ramets connected with the stressed one were mildly injured, implying the supporting and sacrifice function of the unstressed ramets. Physiological integration did not mediate the translocation of Na+ among ramets, but induced a higher expression of salt overly sensitive (SOS) genes in the stressed ramets, consequently reducing the accumulation of Na+ in leaves and roots. In addition, physiological integration upregulated the genes expression and enzymes activity of catalase (CAT) and peroxidase (POD) in both stressed and unstressed ramets. This granted a stronger antioxidant ability of the whole clonal plants under salt stress. Enhanced Na+ transfer and increased reactive oxygen species (ROS) scavenging are mechanisms that likely contribute to the physiological integration leading to the salt tolerance of bermudagrass.

[Research on regularity of traditional Chinese medicine in treatment of Alzheimer's disease based on data mining].

To explore prescription medication regularity in the treatment of Alzheimer's disease with traditional Chinese medicine(TCM). With Alzheimer's disease or senile dementia as the subject, collecting and sorting out the journal papers in CNKI were collected as the data source to establish the literature research database of Alzheimer's disease prescriptions, and then the association rule analysis, factor analysis and systematic cluster analysis on the included TCM were conducted. Among the 113 prescriptions included in the standard, the single herb Acori Tatarinowii Rhizoma was the most common. The herbs were mainly warm and flat among four pro-perties, mainly sweet, bitter and spicy among five flavors. The drugs were mainly distributed in five internal organs, and the most commonly used drugs were deficiency tonifying drugs as well as blood activating and stasis removing drugs. In the association rule analysis, it was found that there were 6 drug pairs with the highest association strength. Eight common factors were extracted from the factor analysis, and they were classified into 6 categories in the systematic cluster analysis. The results have shown that the overall principles in treating Alzheimer's disease with modern Chinese medicine are tonifying deficiency, invigorating circulation, activating blood and dispelling phlegm.

SWL-1 Reverses Fluconazole Resistance in Candida albicans by Regulating the Glycolytic Pathway.

Candida albicans is a ubiquitous clinical fungal pathogen. Prolonged use of the first-line antifungal agent fluconazole (FLC) has intensified fungal resistance and limited its effectiveness for the treatment of fungal infections. The combined administration of drugs has been extensively studied and applied. SWL-1 is a lignin compound derived from the Traditional Chinese Medicine Schisandra chinensis. In this study, we show that SWL-1 reverses resistance to fluconazole in C. albicans when delivered in combination, with a sharp decrease in the IC50 of fluconazole from >200 to 3.74 ± 0.25 µg/ml, and also reverses the fluconazole resistance of C. albicans in vitro, with IC50 from >200 to 5.3 ± 0.3 µg/ml. Moreover, killing kinetics curves confirmed the synergistic effects of fluconazole and SWL-1. Intriguingly, when SWL-1 was administered in combination with fluconazole in a mouse model of systemic infection, the mortality of mice was markedly decreased and fungal colonization of the kidney and lung was reduced. Further mechanistic studies showed that SWL-1 significantly decreased intracellular adenosine 5'-triphosphate (ATP) levels and inhibited the function of the efflux pump responsible for fluconazole resistance of C. albicans. Proteomic analysis of the effects of SWL-1 on C. albicans showed that several enzymes were downregulated in the glycolytic pathway. We speculate that SWL-1 significantly decreased intracellular ATP levels by hindering the glycolysis, and the function of the efflux pump responsible for fluconazole resistance of C. albicans was inhibited, resulting in restoration of fluconazole sensitivity in FLC-resistant C. albicans. This study clarified the effects and mechanism of SWL-1 on C. albicans in vitro and in vivo, providing a novel approach to overcoming fungal resistance.

[Professor LI Xiao-ning's experience for post-stroke dysphagia treated with penetrating-needling and swallowing technique of acupuncture].

Professor LI Xiaoning's experience for post-stroke dysphagia treated with penetrating-needling and swallowing technique of acupuncture is summarized in this paper. The key pathogenesis of this disease is dysfunction of zangfu organs, impairment of the house of mental activity and dysfunction of meridian sinew. Innovatively, the anatomic structure related to swallowing is divided into three zones. Based on the distributions of heart, kidney and stomach meridians on the neck, three lines are determined. Hence, the theory of "three-zone and three-line" as well as the penetrating-needling and swallowing technique of acupuncture are put forward. In this paper, the theoretic evidences of penetrating-needling and swallowing technique of acupuncture, point selection and manipulation in treatment of post-stroke dysphagia are introduced.

[Electroacupuncture Improves Limb Locomotor Function Possibly by Suppressing Rho-ROCK â ¡ Pathway Related Factors in Anterior Horns of Spinal Cord in Rats with Acute Spinal Cord Injury].

OBJECTIVE: To observe the effect of electroacupuncture (EA) of "Jiaji" (EX-B 2) on limb locomotor function and expression of Ras homolog gene family member A (RhoA), Rho-associated kinase Ⅱ (ROCK Ⅱ) and myosin light chain (MLC) proteins in the anterior horn of spinal cord in acute spinal cord injury (ASCI) rats, so as to explore its mechanisms under-lying improvement of SCI-induced limb locomotor dysfunction. METHODS: Forty-eight female Wistar rats were randomly divided into sham operation (sham), ASCI model (model), EA EX-B 2 (EA) and ROCK inhibitor (Fasudil) groups which were further divided into 14 d and 28 d subgroups (n=6 in each). The ASCI model was made by using weight drop striking method. Three hours after modeling, EA (100 Hz, 0.4, 0.6 mA) was applied to EX-B 2 (T 9, T 11) for 30 min, once daily for 14 d and 28 d, respectively. The ROCK inhibitor (hydrochloride Fasudil, 10 mg/kg) was administrated by intraperitoneal injection immediately after modeling, once a day, continuously for 14 d or 28 d. The expression of RhoA, ROCK Ⅱ and MLC proteins in the spinal cord anterior horn tissue (T 10) was detected by immunohistochemistry. The rats' hindlimb locomotor function was assessed according to Basso, Beattie and Bresnahan (BBB) locomotor rating scale (21-points). RESULTS: After ASCI, the BBB scores were significantly lower in the model group than in the sham group on day 14 and 28 (P<0.05), and obviously higher in the EA and inhibitor groups than in the model group (P<0.05), suggesting an improvement of the hindlimb locomotor function after EA intervention or suppression of ROCK. Immunohistochemical results indicated that the numbers of RhoA, ROCK Ⅱ and MLC immune-reaction positive cells in the anterior horn of spinal cord were significantly more in the model group than in the sham group (P<0.05), and remarkably decreased in both EA and inhibitor groups on day 14 and 28 relevant to the model group (P<0.05). The therapeutic effects of EA were markedly weaker than those of inhibitor Fasudil in up-regulating BBB score and down-regulating the number of RhoA, ROCK Ⅱ and MLC positive cells (P<0.05). CONCLUSION: EA of EX-B 2 can improve the hindlimb locomotor function in ASCI rats, which may be associated with its effect in down-regulating the expression of RhoA, ROCK Ⅱ and MLC proteins (i.e., inhibiting the RhoA/ROCK signaling pathway) in the anterior horn of spinal cord.

[Effect of Electroacupuncture Intervention at Different Time-points on Locomotor Function and Apoptosis in Rats with Acute Spinal Cord Injury].

OBJECTIVE: To observe the effect of electroacupuncture (EA) intervention at different treatment time-points on locomotor function and neuronal apoptosis in rats with acute spinal cord injury (ASCI), so as to explore its mechanism under-lying improvement of ASCI. METHODS: Seventy-two female Wistar rats were randomly divided into sham operation, ASCI model and EA groups which were further divided into 4 time-points:1, 3, 7 and 14 d (n=6 at each). The ASCI model was established by weight-drop striking the exposed spinal cord (T10) using a NYU impactor device. EA (0.4-0.6 mA, 100 Hz) was applied to bilateral "Jiaji" (EX-B 2) for 30 min, once a day for 1, 3, 7 and 14 days, respectively in the EA group. The Basso-Beattie-Bresnahan (BBB) grading score was used to assess the animals' locomotor function, and H.E. staining was used to display the pathological changes of spinal cord injury at different time points. The TUNEL staining was used to detect the nerve cell apoptosis of spinal cord tissue. RESULTS: After ASCI, the BBB scores were significantly decreased and the numbers of the apoptotic nerve cells considerably increased on day 1, 3, 7 and 14 in the model group compared with the sham operation group (P<0.05). In addition, H.E. staining showed severe damage of the spinal cord tissue, infiltration of inflammatory cells, increase of dead nerve neurons and glia cells in the number from day 3 to 7, and additional increase of vacuoles on day 14. Following EA intervention, the decrease of BBB scores and the increase of apoptotic nerve cell numbers were markedly suppressed on day 3, 7 and 14 (P<0.05). The TUNEL staining showed a decrease of the apoptotic nerve cells from day 3 on and an improvement of the injured tissue structure from day 7 to 14 in the EA group. CONCLUSIONS: EA stimulation of EX-B 2 can significantly improve locomotor function, and lighten the spinal cord injury in ASCI rats, presenting a time-dependant tendency, which may be associated with its effect in reducing neuronal apoptosis in the spinal cord.

[Chemo-preventive effect of Angelica sinensis' supercritical extracts on AOM/DSS-induced mouse colorectal carcinoma associated with inflammation].

To study the chemo-preventive effect of the supercritical extracts from Angelica sinensis (SFE-AS) on induced colorectal carcinoma in mice by using the AOM/DSS-induced male mice colorectal carcinoma model, and discuss its possible action mechanism. Male Balb/c mice were subcutaneously injected with single dose of azoxymethane (AOM, 10 mg x kg(-1) body weight). One week later, they were given 2% dextran sodium sulfate (DSS) in drinking water for 7 days to induce colorectal carcinoma. Each drug group was orally administered with supercritical extracts from Angelica sinensis at 15, 30, 60 mg x kg(-1) until the 17th week. The tumor incidence rate of the SFE-AS group, mice tumor-bearing quantity and tumor-bearing volume of the SFE-AS group were lower than that of the AOM/DSS model control group, which may be related with the significant reduction of PCNA, COX-2, iNOS in the AOM/DSS-induced mouse colorectal carcinoma model associated with inflammation by SFE-AS. According to the results of this study, SFE-AS showed an intervention effect in the incidence and development of AOM/DSS-induced mouse colorectal carcinoma associated with inflammation, and could be further used in chemo-preventive studies on human colorectal carcinoma.

PPARγ agonist from Chromolaena odorata.

A phytochemical investigation of Chromolaena odorata resulted in the isolation of five new compounds, 5aα,6,9,9aß,10-pentahydro-10ß-hydroxy-7-methylanthra[1,2-d][1,3]dioxol-5-one (1), 1,2-methylenedioxy-6-methylanthraquinone (2), 3-hydroxy-1,2,4-trimethoxy-6-methylanthraquinone (3), 3-hydroxy-1,2-dimethoxy-6-methylanthraquinone (4), and 7-methoxy-7-epi-medioresinol (5), together with 12 known compounds, odoratin (6), 3ß-acetyloleanolic acid (7), ursolic acid (8), ombuin (9), 4,2'-dihydroxy-4',5',6'-trimethoxychalcone (10), (-)-pinoresinol (11), austrocortinin (12), tianshic acid (13), cleomiscosin D (14), (-)-medioresinol (15), (-)-syringaresinol (16), and cleomiscosin A (17). All the compounds were evaluated for their PPARγ transactivation activity, and compound 6 showed moderate activity with an EC(50) value of 3.10 µM.

Monoterpenoid indole alkaloids from Gardneria ovata.

Eight new monoterpenoid indole alkaloids, gardfloramine-9-O-ß-D-glucopyranoside (1), 19(E)-18-demethoxygardfloramine-N(4)-oxide (2), gardfloramine-N(4)-oxide (3), 18-demethylgardfloramine (4), 19(E)-9,18-didemethoxygardneramine (5), 19(E)-11-methoxy-9,18-didemethoxygardneramine (6), 9-demethoxy-18-demethylgardneramine (7), and minfiensine-N(4)-oxide (8), along with six known alkaloids, were isolated from Gardneria ovata. The structures of the new alkaloids were established by means of spectroscopic methods. None of the compounds were cytotoxic to five human cancer cell lines.

Triterpene and sterol derivatives from the roots of Breynia fruticosa.

A new nor-ceanothane-type triterpenoid, breynceanothanolic acid (1), and seven novel 4α-methyl sterols, fruticosides A-G (2-8), were obtained from the roots of Breynia fruticosa. The new compound structures were established by means of extensive spectroscopic and chemical methods. Compounds 7 and 8 are sulfur-containing derivatives of the 4α-methyl sterols, and the sugar moiety of compounds 4, 5, 7, and 8 (L-quinovose) is uncommon in plants. Compounds 1 and 2 exhibited moderate cytotoxicity against five human cancer cell lines.

Sterols and terpenoids from Melia azedarach.

Three new sterols (1-3) including an unprecedented ring A-seco natural product (1), five new terpenoids (4-8), and 15 known compounds were isolated from the bark of Melia azedarach. Their structures were elucidated by means of spectroscopic data, and the structure of 1 was confirmed by X-ray crystallography.

[Analysis of essential oil in herba ephedrae-ramulus cinnamomi by GC-MS and chemometric resolution method].

Gas chromatography/mass spectrometry, chemometric resolution method ( CRM) and overall volume integration method were used to analyze the essential components of herbal pair Herba Ephedrae-Ramulus Cinnamomi (HP HE-RC) and compare it with that of single herbs HE and RC. 72, 68, and 97 essential components in essential oil of HE, RC, and HP HE-RC were determined, accounting for 90. 08% , 91. 62% , and 89. 76% of total contents of essential oil of HE, RC, and HP HE-RC, respectively. The numbers of essential components of HP HE-RC are almost the summation of that of two single herbs, but some relative contents of them are changed. Some new components, such as 1, 6-dimethylhepta-1,3,5-triene, tetracyclo[4. 2. 1.1 (2,5 ). 0 (9,10) ] deca-3,7-diene, globulol, ( E, E) -6, 10,14-trimethyl-5,9,13-pentadecatrien-2 -one, etc. have been found in HP HE-RC because of chemical reactions and physical changes during the course of decocation.

[Chemical components in essential oils from tender branches and leaves of Rhododendron].

AIM: To analyze and compare the compositions in essential oils from branches and leaves of Rhododendron simsii Planch. and Rhododendron naamkwanense Merr. METHODS: Essential oils were extracted by water distillation according to Chinese Pharmacopoeia and analyzed by capillary gas chromatography-mass spectrometry as well as chemometrics resolution method and authentic compounds. The relative contents of each component in the essential oils were obtained by normalization of peak areas. RESULTS: A total of 124 components were identified, of which 48 compounds were existed in both of the samples. Ninety four compounds accounted for 84.47% of the essential oil from Rhododendron simsii Planch. and seventy eight components accounted for 90.25% of the total essential oil from Rhododendron naamkwanense Merr. were identified. 72.76% and 88.07% of the components in Rhododendron simsii Planch and Rhododendron naamkwanense Merr., respectively, included oxygen element. They are mainly terpenol, acids and esters. 1-octen-3-ol (4.00%, 7.90%), 1,6-octadien-3-ol, 3,7-dimethyl-(12.60%, 3.48%), 9,12,15-octadecatrienoic acid, [Z, Z, Z]- (1.15%, 45.34%), phytol (15.21%, 8.56%), p-menth-1-en-8-ol (2.15%, 3.29%), and 9,12,15-octadecatrienoic acid, ethyl ester, [Z,Z,Z]- (9.16%, 8.01%) were their common main compounds, which accounted for 44. 27% and 76.58% of the total amount of the two essential oil samples, respectively. In addition, n-hexadecanoic acid (7.73%), 9,12-octadecadienoic acid (1.85%) and tetracosanoic acid, methyl ester (1.38%) were also the main compounds in essential oil from Rhododendron simsii Planch. CONCLUSION: Much higher reliability and accuracy were obtained with the help of chemometrics resolution method and authentic n-alkane standard solutions than those of using GC-MS alone.

Temperature-programmed retention indices for gas chromatography-mass spectroscopy analysis of plant essential oils.

A total of 95 volatile compounds from the essential oil in buds of Syringa oblata Lindl (lilac) were identified by gas chromatography-mass spectrometry (GC-MS) combined with heuristic evolving latent projections (HELP) and moving subwindow searching (MSS). The identified compounds are mainly aliphatic, terpenes and aromatic compounds. Their temperature-programmed retention indices (PTRIs) on HP-5MS and DB-35MS at three heating rates of 2, 4 and 6 degrees C/min from 80 to 290 degrees C were obtained, which showed that aliphatic compounds give nearly constant PTRIs and PTRIs of terpenoids do not vary much at different heating rates. But PTRIs of aromatic compounds exhibit relatively large temperature dependence. PTRIs vary much more on DB-35MS than those on HP-5MS according to the compound types. In general, differences of PTRIs between the two columns increase from aliphatic compounds to terpenoids to polycyclic aromatic compounds. The PTRIs in different heating rates were used as cross-references in the identification of components in the essential oil. When they were used in analysis of essential oil from flowers of lilac, good results were obtained. These PTRIs would be a part of our PTRI database being constructed on components from plant essential oils. The results also showed that efficiency and reliability were improved greatly when chemometric method and PTRIs were used as assistants of GC-MS in identification of chemical components in plant essential oils.

Multicomponent spectral correlative chromatography applied to complex herbal medicines.

In this study, a novel chemometric algorithm is presented to facilitate the comparison of relevant chemical components from different herbal samples. This so-called multicomponent spectral correlative chromatography (MSCC) is developed to detect and decide whether two chromatographic clusters are correlated spectrally with each other. The target chromatographic cluster is first partitioned from one herbal spectrochromatogram obtained by hyphenated chromatography. Then, a projection operator is constructed with the principal spectral features extracted from the target to judge the presence or absence of a spectral correlative chromatographic cluster within another herbal spectrochromatogram. For this judgment, congruence coefficient between the original spectral vector and its projected residual is proposed to eliminate the influences from background and noises, especially heteroscedastic noises in the original data. The performance of the MSCC algorithm is demonstrated on both simulated data and real data, and its advantages and disadvantages are also discussed in some detail.

Comparison of the volatile constituents of Artemisia capillaris from different locations by gas chromatography-mass spectrometry and projection method.

The volatile chemical constituents of Artemisia capillaries (an important traditional Chinese medicine) were determined by gas chromatography-mass spectrometry (GC-MS) and sub-window factor analysis (SFA). Seventy-five components were separated and 43 of them were qualitatively and quantitatively determined, which represented about 89.03% of the total content. This profile was then used to identify and assess the consistency of the herb by using an orthogonal projection method. Four different sources of A. capillaries were analyzed and compared with each other. Among the components determined, there were 51 components coexisting in all samples although the relative peak areas of a few showed variations. It is the first time to apply orthogonal projection method to the comparison of different samples, and it reduces the burden of qualitative analysis as well as the subjectivity. The results showed a fair consistency in their GC-MS fingerprint. A. capillaris was distinguished from Artemisia sacrorum L., a possible substitute in traditional Chinese medicine by comparing the fingerprints with each other.