Comprehensive metabolome characterization and comparison between two sources of Dragon's blood by integrating liquid chromatography/mass spectrometry and chemometrics.

Dragon's Blood (DB) serves as a precious Chinese medicine facilitating blood circulation and stasis dispersion. Daemonorops draco (D. draco; Qi-Lin-Jie) and Dracaena cochinchinensis (D. cochinchinenesis; Long-Xue-Jie) are two reputable plant sources for preparing DB. This work was designed to comprehensively characterize and compare the metabolome differences between D. draco and D. cochinchinenesis, by integrating liquid chromatography/mass spectrometry and untargeted metabolomics analysis. Offline two-dimensional liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry (2D-LC/IM-QTOF-MS), by utilizing a powerful hybrid scan approach, was elaborated for multicomponent characterization. Configuration of an XBridge Amide column and an HSS T3 column in offline mode exhibited high orthogonality (A0 0.80) in separating the complex components in DB. Particularly, the hybrid high-definition MSE-high definition data-dependent acquisition (HDMSE-HDDDA) in both positive and negative ion modes was applied for data acquisition. Streamlined intelligent data processing facilitated by the UNIFI™ (Waters) bioinformatics platform and searching against an in-house chemical library (recording 223 known compounds) enabled efficient structural elucidation. We could characterize 285 components, including 143 from D. draco and 174 from D. cochinchinensis. Holistic comparison of the metabolomes among 21 batches of DB samples by the untargeted metabolomics workflows unveiled 43 significantly differential components. Separately, four and three components were considered as the marker compounds for identifying D. draco and D. cochinchinenesis, respectively. Conclusively, the chemical composition and metabolomic differences of two DB resources were investigated by a dimension-enhanced analytical approach, with the results being beneficial to quality control and the differentiated clinical application of DB.

Spatial Distribution and Characterization of the Small-Molecule Metabolites and In Situ Hydrolyzed Oligosaccharides in the Rhizome of Glycyrrhiza uralensis by Desorption Electrospray Ionization-Mass Spectrometry Imaging and High-Resolution Liquid Chromatography-Mass Spectrometry.

Characterization and spatial distribution studies of the metabolome in plants are crucial for revealing the physiology of plants and developing functional foods. Using the rhizome of Glycyrrhiza uralensis as a case, we integrated desorption electrospray ionization-mass spectrometry imaging (DESI-MSI) and high-resolution liquid chromatography/mass spectrometry approaches aimed at characterizing and locating both the small molecules and the macromolecular polysaccharides. Under the optimal conditions, 21 flavonoids and 12 triterpenoids were detected and characterized in different tissues of the rhizome and another 19 components were characterized exclusively by DESI-MSI. Combined with hydrophilic interaction chromatography/ion mobility-quadrupole time-of-flight mass spectrometry, eight different degrees of polymerization of oligosaccharides (after in situ acid hydrolysis) were characterized from the rhizome of G. uralensis. Majority of these metabolites are located in the cortex, phloem, and medulla, which lays the foundation for understanding the physiology of G. uralensis. The useful information can benefit the sustainable utilization and further development of Glycyrrhiza resource.

Polygonatum odoratum polysaccharide attenuates lipopolysaccharide-induced lung injury in mice by regulating gut microbiota.

Polygonatum odoratum is appreciated for its edible and medicinal benefits especially for lung protection. However, the contained active components have been understudied, and further research is required to fully exploit its potential application. We aimed to probe into the beneficial effects of Polygonatum odoratum polysaccharide (POP) in lipopolysaccharide-induced lung inflammatory injury mice. POP treatment could ameliorate the survival rate, pulmonary function, lung pathological lesions, and immune inflammatory response. POP treatment could repair intestinal barrier, and modulate the composition of gut microbiota, especially reducing the abundance of Klebsiella, which were closely associated with the therapeutic effects of POP. Investigation of the underlying anti-inflammatory mechanism showed that POP suppressed the generation of pro-inflammatory molecules in lung by inhibiting iNOS+ M1 macrophages. Collectively, POP is a promising multi-target microecological regulator to prevent and treat the immuno-inflammation and lung injury by modulating gut microbiota.

Characterization of ginsenosides from Panax japonicus var. major (Zhu-Zi-Shen) based on ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry and desorption electrospray ionization-mass spectrometry imaging.

BACKGROUND: Panax japonicus var. major (PJM) belongs to the well-known ginseng species used in west China for hundreds of years, which has the effects of lung tonifying and yin nourishing, and exerts the analgesic, antitussive, and hemostatic activities. Compared with the other Panax species, the chemical composition and the spatial tissue distribution of the bioactive ginsenosides in PJM have seldom been investigated. METHODS: Ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/QTOF-MS) and desorption electrospray ionization-mass spectrometry imaging (DESI-MSI) were integrated for the systematic characterization and spatial tissue distribution studies of ginsenosides in the rhizome of PJM. Considering the great difficulty in exposing the minor saponins, apart from the conventional Auto MS/MS (M1), two different precursor ions list-including data-dependent acquisition (PIL-DDA) approaches, involving the direct input of an in-house library containing 579 known ginsenosides (M2) and the inclusion of the target precursors screened from the MS1 data by mass defect filtering (M3), were developed. The in situ spatial distribution of various ginsenosides in PJM was profiled based on DESI-MSI with a mass range of m/z 100-1500 in the negative ion mode, with the imaging data processed by the High Definition Imaging (HDI) software. RESULTS: Under the optimized condition, 272 ginsenosides were identified or tentatively characterized, and 138 thereof were possibly not ever reported from the Panax genus. They were composed by 75 oleanolic acid type, 22 protopanaxadiol type, 52 protopanaxatriol type, 16 octillol type, 19 malonylated, 35 C-17 side-chain varied, and 53 others. In addition, the DESI-MSI experiment unveiled the differentiated distribution of saponins, but the main location in the cork layer and phloem of the rhizome. The abundance of the oleanolic acid ginsenosides was high in the rhizome slice of PJM, which was consistent with the results obtained by UHPLC/QTOF-MS. CONCLUSION: Comprehensive characterization of the ginsenosides in the rhizome of PJM was achieved, with a large amount of unknown structures unveiled primarily. We, for the first time, reported the spatial tissue distribution of different subtypes of ginsenosides in the rhizome slice of PJM. These results can benefit the quality control and further development of PJM and the other ginseng species.

Multiple heart-cutting two-dimensional liquid chromatography/charged aerosol detector assay of ginsenosides for quality evaluation of ginseng from diverse Chinese patent medicines.

For quality control of Chinese patent medicines (CPMs) containing the same herbal medicine or different herbal medicines that have similar chemical composition, current ″one standard for one species″ research mode leads to poor universality of the analytical approaches unfavorable to discriminate easily confused species. Herein, we were aimed to elaborate a multiple heart-cutting two-dimensional liquid chromatography/charged aerosol detector (MHC-2DLC/CAD) approach to quantitatively assess ginseng from multiple CPMs. Targeting baseline resolution of 16 ginsenosides (noto-R1/Rg1/Re/Rf/Ra2/Rb1/Rc/Ro/Rb2/Rb3/Rd/Rh1/Rg2/Rg3/Rg3(R)/24(R)-p-F11), experiments were conducted to optimize key parameters and validate its performance. A Poroshell 120 EC-C18 column and an XBridge Shield RP18 column were separately utilized in the first-dimensional (1D) and the second-dimensional (2D) chromatography. Eight consecutive cuttings could achieve good separation of 16 ginsenosides within 85 min. The developed MHC-2DLC/CAD method showed good linearity (R2 > 0.999), repeatability (RSD < 6.73%), stability (RSD < 5.63%), inter- and intra-day precision (RSD < 5.57%), recovery (93.76-111.14%), and the limit of detection (LOD) and limit of quantification (LOQ) varied between 0.45-2.37 ng and 0.96-4.71 ng, respectively. We applied it to the content determination of 16 ginsenosides simultaneously from 28 different ginseng-containing CPMs, which unveiled the ginsenoside content difference among the tested CPMs, and gave useful information to discriminate ginseng in the preparation samples, as well. The MHC-2DLC/CAD approach exhibited advantages of high specificity, good separation ability, and relative high analysis efficiency, which also justified the feasibility of our proposed ″Monomethod Characterization of Structure Analogs″ strategy in quality evaluation of diverse CPMs that contained different ginseng.

An efficient approach addressing the chemical complexity of Jiawei Fangji Huangqi decoction by integrating ultra-high-performance liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry and intelligent data processing workflows.

A challenge in the quality control of traditional Chinese medicine is the systematic multicomponent characterization of the compound formulae. Jiawei Fangji Huangqi, a modified form of Fangji Huangqi, is a prescription comprising seven herbal medicines. To address the chemical complexity of the Jiawei Fangji Huangqi decoction, we integrated ion mobility-quadrupole time-of-flight high-definition MSE coupled to ultra-high-performance liquid chromatography and intelligent data processing workflows available in the UNIFI software package. Good chromatographic separation was achieved on CORTECS UPLC T3 column within 52 min, and high-accuracy MS2 data were acquired using high-definition MSE in the negative and positive modes. A chemical library of 1250 compounds was created and incorporated into the UNIFI software to enable automatic peak annotation of the high-definition MSE data. We identified or tentatively characterize 430 compounds in the Jiawei Fangji Huangqi decoction. The potential superiority of high-definition MSE over conventional MS data acquisition approaches was revealed in its spectral quality (MS2 ), differentiation of isomers, separation of coeluting compounds, and target mass coverage. The multiple components of the Jiawei Fangji Huangqi decoction were elucidated, offering insight into its improved pharmacological action compared with that of the Fangji Huangqi formula.

A practical strategy enabling more reliable identification of ginsenosides from Panax quinquefolius flower by dimension-enhanced liquid chromatography/mass spectrometry and quantitative structure-retention relationship-based retention behavior prediction.

To accurately identify the metabolites is crucial in a number of research fields, and discovery of new compounds from the natural products can benefit the development of new drugs. However, the preferable phytochemistry or liquid chromatography/mass spectrometry approach is time-/labor-extensive or receives unconvincing identifications. Herein, we presented a strategy, by integrating offline two-dimensional liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry (2D-LC/IM-QTOF-MS), exclusion list-containing high-definition data-dependent acquisition (HDDDA-EL), and quantitative structure-retention relationship (QSRR) prediction of the retention time (tR), to facilitate the in-depth and more reliable identification of herbal components and thus to discover new compounds more efficiently. Using the saponins in Panax quinquefolius flower (PQF) as a case, high orthogonality (0.79) in separating ginsenosides was enabled by configuring the XBridge Amide and CSH C18 columns. HDDDA-EL could improve the coverage in MS2 acquisition by 2.26 folds compared with HDDDA (2933 VS 1298). Utilizing 106 reference compounds, an accurate QSRR prediction model (R2 = 0.9985 for the training set and R2 = 0.88 for the validation set) was developed based on Gradient Boosting Machine (GBM), by which the predicted tR matching could significantly reduce the isomeric candidates identification for unknown ginsenosides. Isolation and establishment of the structures of two malonylginsenosides by NMR partially verified the practicability of the integral strategy. By these efforts, 421 ginsenosides were identified or tentatively characterized, and 284 thereof were not ever reported from the Panax species. The current strategy is thus powerful in the comprehensive metabolites characterization and rapid discovery of new compounds from the natural products.

Comparative Characterization of the Ginsenosides from Six Panax Herbal Extracts and Their In Vitro Rat Gut Microbial Metabolites by Advanced Liquid Chromatography-Mass Spectrometry Approaches.

Ginseng extracts are extensively used as raw materials for food supplements and herbal medicines. This study aimed to characterize ginsenosides obtained from six Panax plant extracts (Panax ginseng, red ginseng, Panax quinquefolius, Panax notoginseng, Panax japonicus, and Panax japonicus var. major) and compared them with their in vitro metabolic profiles mediated by rat intestinal microbiota. Ultrahigh-performance liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry (UHPLC/IM-QTOF-MS) with scheduled multiple reaction monitoring (sMRM) quantitation methods were developed to characterize and compare the ginsenoside composition of the different extracts. After in vitro incubation, 248 ginsenosides/metabolites were identified by UHPLC/IM-QTOF-MS in six biotransformed samples. Deglycosylation was determined to be the main metabolic pathway of ginsenosides, and protopanaxadiol-type and oleanolic acid-type saponins were easier to be easily metabolized. Compared with the ginsenosides in plant extracts, those remaining in six biotransformed samples were considerably fewer after biotransformation for 8 h. However, the compositional differences in four subtypes of the ginsenosides among the six Panax plants became more distinct.

Collision Cross Section Prediction Based on Machine Learning.

Ion mobility-mass spectrometry (IM-MS) is a powerful separation technique providing an additional dimension of separation to support the enhanced separation and characterization of complex components from the tissue metabolome and medicinal herbs. The integration of machine learning (ML) with IM-MS can overcome the barrier to the lack of reference standards, promoting the creation of a large number of proprietary collision cross section (CCS) databases, which help to achieve the rapid, comprehensive, and accurate characterization of the contained chemical components. In this review, advances in CCS prediction using ML in the past 2 decades are summarized. The advantages of ion mobility-mass spectrometers and the commercially available ion mobility technologies with different principles (e.g., time dispersive, confinement and selective release, and space dispersive) are introduced and compared. The general procedures involved in CCS prediction based on ML (acquisition and optimization of the independent and dependent variables, model construction and evaluation, etc.) are highlighted. In addition, quantum chemistry, molecular dynamics, and CCS theoretical calculations are also described. Finally, the applications of CCS prediction in metabolomics, natural products, foods, and the other research fields are reflected.

Pseudotargeted Metabolomics Approach Enabling the Classification-Induced Ginsenoside Characterization and Differentiation of Ginseng and Its Compound Formulation Products.

The use of diversified ginseng extracts in health-promoting foods is difficult to differentiate, as they share bioactive ginsenosides among different Panax species (e.g., P. ginseng, P. quinquefolius, P. notoginseng, and P. japonicus) and different parts (e.g., root, leaf, and flower). This work was designed to develop a pseudo-targeted metabolomics approach to discover ginsenoside markers facilitating the precise authentication of ginseng and its use in compound formulation products (CFPs). Versatile mass spectrometry experiments on the QTrap mass spectrometer achieved classified characterization of the neutral, malonyl, and oleanolic acid-type ginsenosides, with 567 components characterized. A pseudo-targeted metabolomics approach by multiple reaction monitoring (MRM) of 262 ion pairs could assist to establish key identification points for 12 ginseng species. The simultaneous detection of 14 markers enabled the identification of ginseng from 15 ginseng-containing CFPs. The pseudo-targeted metabolomics strategy enabled better performance in differentiating among multiple ginseng, compared with the full-scan high-resolution mass spectrometry approach.

Sweritranslactone D, a hepatoprotective novel secoiridoid dimer with tetracyclic lactone skeleton from heat-transformed swertiamarin.

Swertia mileensis, known as Qing-Ye-Dan (QYD), has been documented in Chinese Pharmacopoeia to cure hepatitis. Interestingly, its announced main active component, swertiamarin, could not be detected in the decoction, which indicated that the efficacy of QYD might be attributed to heat-transformed products of swertiamarin (HTPS). Further investigation on HTPS led to the isolation of sweritranslactone D (1), a novel secoiridoid dimer possessing a tetracyclic lactone skeleton, with better hepatoprotective activity than N-acetyl-L-cysteine in vitro.

Association between musculoskeletal ultrasonography and bone remodelling markers and its role in disease monitoring of gout and hyperuricaemia.

OBJECTIVES: To evaluate associations between bone destruction markers and musculoskeletal ultrasonography (MU) findings in patients with gout and hyperuricaemia and clarify the role of MU in treatment responsiveness. METHODS: One-hundred and fifty patients with gout and 100 patients with hyperuricaemia were divided into five groups according to MU manifestations. Circulating Dickkopf-1 (DKK-1) and receptor activator of nuclear factor-κB ligand (RANKL) levels were measured. Thirty patients from the gout group and 10 from the hyperuricaemia group, were treated for 1 year with urate-lowering therapy (ULT). RESULTS: Patients with gout and tophus and/or bone erosion had the highest DKK-1 and RANKL levels. Patients with gout and MU-evidenced aggregates and/or double-contour signs had higher DKK-1 and RANKL levels than the normal MU group (p<0.001). Patients with hyperuricaemia and abnormal MU findings had significantly higher DKK-1 and RANKL levels than those with normal MU findings. DKK-1 and RANKL levels positively correlated with disease duration in patients with gout (r=0.430, p<0.001; r=0.359, p<0.001, respectively) and hyperuricaemia (r=0.446, p<0.001; r=0.379, p<0.001, respectively). After ULT, MU abnormalities disappeared in 12 and 8 patients with gout and hyperuricaemia, respectively. The largest tophus diameter decreased in patients with gout (t=6.092, p<0.001). DKK-1 and RANKL concentrations significantly decreased in all patients. Lower serum urate levels corresponded with higher ratios of normal MU features in all patients. CONCLUSIONS: In patients with gout and hyperuricaemia, MU manifestations were associated with DKK-1 and RANKL levels and were ameliorated after ULT. Thus, MU could be a useful tool in assessing bone remodelling and monitoring disease responsiveness.

[Pollution Characteristics and Ecological Risk Assessment of Phthalate Esters (PAEs) in the Surface Water of Jiaozhou Bay].

In order to better understand phthalate esters (PAEs) pollution in Jiaozhou Bay, surface water samples were collected for content analysis in August and November 2015 and January 2016. Fifteen kinds of PAEs were detected by stir bar sorptive extraction and gas chromatography-mass spectrometry. The content, composition, spatial distribution, seasonal variation, and ecological risk assessment of the PAEs in the surface waters were examined and analyzed. The results showed that:① The total concentrations of PAEs in the surface seawater in August and November 2015 and January 2016 were 3.63-21.20 µg·L-1, 2.24-12.60 µg·L-1, and 0.01-4.15 µg·L-1, respectively, and the average concentrations were 11.10 µg·L-1, 5.26 µg·L-1, and 0.80 µg·L-1, respectively. ② Influenced by runoff and ocean currents, the concentration of PAEs in the surface water of Jiaozhou Bay is higher near the shore and lower in the middle, and the total concentration of the east coast is higher than that of the west coast. Compared with surveys of other rivers and oceans, the PAEs content in the surface water of Jiaozhou Bay is moderate, but it is heavily polluted compared with other oceans. ③ Considering the rainfall and other factors, the distribution of PAEs in the three seasons followed the order summer > autumn > winter. The main PAEs detected were DBP, BBP, and DEHP. ④ The results of the ecological risk assessment showed that the risk quotient (RQ) of DBP at each station in Jiaozhou Bay was greater than 1; that is, the ecological risk was relatively large, while the risk of the other PAEs (RQ<1) was small. PAEs have become a potentially threatening organic pollutant in Jiaozhou Bay. Their behavior and the ecological hazards that they present to the environment still require further study.

[Influence of Six Digestion Methods on the Determination of Polystyrene Microplastics in Organisms Using the Fluorescence Intensity].

Microplastic pollution has become a global environmental problem and is a cause of great concern. To evaluate the biological effects of microplastics, microplastics in organisms need to be accurately quantified. The quantification of microplastics in organisms using the fluorescence intensity is common; the digestion of biological samples is an important pretreatment method. However, the microplastics may be destroyed by digestion, which affects the fluorescence intensity of the microplastics and results in large deviations between measured and true values. In this study, six commonly used digestive agents were studied:KOH, NaOH, H2O2, HNO3, HNO3:HCl, and HNO3:HClO4. The effect of different digestion methods on the fluorescence intensity and surface morphology of microplastics was studied and the most suitable protocol was selected. The results show that, among the six different digestion methods, KOH digestion (100 g·L-1, 60℃) has the least influence on the fluorescence intensity of the microplastics and does not affect their surface morphology. The other five digestion methods lead to different degrees of reduction of the fluorescence intensity of microplastics and damage the microplastics' surface (aggregation, bubbles, scratches, and depressions). In addition, the KOH digestion method was used to extract microplastics from biological samples. The recovery rate was ≥ 96.3%±0.5%, indicating that the KOH digestion method is suitable for fluorescent microplastics in biological samples.

Interstitial lung disease in non-sicca onset primary Sjögren's syndrome: a large-scale case-control study.

AIM: This study investigated the common initial clinical presentations of primary Sjögren's syndrome (pSS) with interstitial lung disease (ILD) and explored differences between sicca and non-sicca onset pSS-ILD patients. METHOD: A total of 1341 SS patients hospitalized between 2003 and 2012 were retrospectively reviewed. Of them, 102 were analyzed and recruited to examine the differences between non-sicca and sicca onset. RESULTS: Fifty-one percent of pSS-ILD patients presented with non-sicca onset. Although the mean diagnosis time was equal, only 4% of non-sicca onset patients were diagnosed with pSS at onset versus 34% with sicca onset (P = 0.000). Hyperglobulinemia, elevated rheumatoid factor (RF) titer, and anti-SSA and/or anti-SSB presence were less predominant in patients with non-sicca onset (immunoglobulin G, 16 [12-21] vs. 21 [15-28] g/L, P = 0.032; RF, 22 [20-171] vs. 104 [20-237] IU/mL, P = 0.048; anti-SSA and/or anti-SSB presence, 33% vs. 72%, P = 0.000). The usual interstitial pneumonia pattern was more commonly seen in non-sicca onset patients (20.0% vs. 14.3%). The high-resolution computed tomography score was higher (12 [88-15] vs. 8 [5-13], P = 0.070) and predicted total lung capacity and forced vital capacity were lower (87 ± 23% vs. 97 ± 20%, P = 0.050; 88 ± 28% vs. 100 ± 27%, P = 0.089) in non-sicca patients. CONCLUSION: Non-sicca is a common initial manifestation in pSS-ILD. Anti-SSA presence, elevated RF titer and hyperglobulinemia were less predominant, and pulmonary complications were more progressive and severe in non-sicca onset patients than sicca onset patients.

Comparison of six digestion methods on fluorescent intensity and morphology of the fluorescent polystyrene beads.

Effect of digestion methods on fluorescence intensity of fluorescent polystyrene (PS) beads was poorly understood, which may affect the accuracy of toxicity test of the fluorescent PS beads exposed to marine organisms. Therefore, six digestion approaches were compared on fluorescence intensities and properties of three commercial fluorescent PS beads. Among all the protocols, the digestion using KOH (10% w/v, 60 °C) (KOH-digestion) had no effect on the fluorescence intensity, morphology and composition of the three fluorescent PS beads. Moreover, the extraction efficiency ≥ 95.3 ±â€¯0.2% of fluorescent PS beads in Daphnia magna and zebrafish, confirming its feasibility in fluorescent PS beads quantitative analysis. However, the fluorescence intensities of fluorescent PS beads digested by other five protocols were significantly decreased, as well as the change of morphology and composition on fluorescent PS beads. Overall, the KOH-digestion is an optimal protocol for extracting fluorescent PS beads in biological samples.

Values of the Wells and revised Geneva scores combined with D-dimer in diagnosing elderly pulmonary embolism patients.

BACKGROUND: Pulmonary embolism (PE) can be difficult to diagnose in elderly patients because of the coexistent diseases and the combination of drugs that they have taken. We aimed to compare the clinical diagnostic values of the Wells score, the revised Geneva score and each of them combined with D-dimer for suspected PE in elderly patients. METHODS: Three hundred and thirty-six patients who were admitted for suspected PE were enrolled retrospectively and divided into two groups based on age (≥65 or <65 years old). The Wells and revised Geneva scores were applied to evaluate the clinical probability of PE, and the positive predictive values of both scores were calculated using computed tomography pulmonary arteriography as a gold standard; overall accuracy was evaluated by the area under the curve (AUC) of receiver operator characteristic curve; the negative predictive values of D-dimer, the Wells score combined with D-dimer, and the revised Geneva score combined with D-dimer were calculated. RESULTS: Ninety-six cases (28.6%) were definitely diagnosed as PE among 336 cases, among them 56 cases (58.3%) were ≥65 years old. The positive predictive values of Wells and revised Geneva scores were 65.8% and 32.4%, respectively (P < 0.05) in the elderly patients; the AUC for the Wells score and the revised Geneva score in elderly was 0.682 (95% confidence interval [CI]: 0.612-0.746) and 0.655 (95% CI: 0.584-0.722), respectively (P = 0.389). The negative predictive values of D-dimer, the Wells score combined with D-dimer, and the revised Geneva score combined with D-dimer were 93.7%, 100%, and 100% in the elderly, respectively. CONCLUSIONS: The diagnostic value of the Wells score was higher than the revised Geneva score for the elderly cases with suspected PE. The combination of either the Wells score or the revised Geneva score with a normal D-dimer concentration is a safe strategy to rule out PE.