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In this paper, it is shown that the extended Hilbert's inequality for double series can be refined by the aid of the Euler-Maclaurin summation formula. The extreme cases $p\rightarrow 1^+$ and $q\rightarrow+\infty$ are discussed. [ABSTRACT FROM AUTHOR]

Radix Polygoni Multiflori (PM) is a well-known nootropic used in traditional Chinese medicine (TCM). Considering the efficacy and application discrepancy between raw (RPM) and processed PM (PPM), the similarities and differences between them in the treatment of vascular dementia (VaD) is intriguing. In this study, a VaD rat model was constructed by 2-vessel occlusion (2-VO). During 28 days of treatment, plasma was collected on days 7, 14, 21, and 28 after the start of dosing and the metabolic profile was analyzed by HPLC-MS/MS-based metabolomics. The Morris Water Maze Test, hematoxylin-eosin and Nissl staining, and biochemical analysis were used to assess cognitive function, pathogenic alterations and oxidative stress, respectively. RPM and PPM effectivelyreducedthe 2VO-induced cognitive impairment and mitigated histological alterations in hippocampus tissue. The 2-VO model significantly elevated MDA level and decreased SOD activity and GSH level, indicating severe oxidative stress, which could also be attenuated by RPM and PPM treatment. RPM outperformed PPM in decreasing MDA levels while PPM outperformed RPM in increasing GSH levels. Differential metabolites were subjected to Metabolite Set Enrichment Analysis (MSEA) and genes corresponding to proteins having interactions with metabolites were further annotated with Gene Ontology (GO). Both RPM and PPM ameliorated VaD-relevant vitamin B6 metabolism, pentose phosphate pathways, and taurine and hypotaurine metabolism. In addition, the metabolism of cysteine and methionine was regulated only by RPM, and riboflavin metabolism was modulated only by PPM. The results suggested that raw and processed PM had comparable efficacy in the treatment of VaD but also with some mechanistic differenece.

Icariin and epimedins A, B, C are a series of active flavonol glycoside in Epimedium brevicornum Maxim. A pilot-scale preparative high performance liquid chromatographic (HPLC) method was developed to purify the four flavonol glycosides as reference standards from the crude extract of Epimedium brevicornum Maxim. After the crude extract containing approximately 20% flavonols was enriched using macropore resin, the obtained target fractions were subjected to pilot-scale preparative HPLC purification. With the aid of a self-packed pilot-scale preparative column (220 mm x 77 mm, 10 microm), the 4 target compounds were separated well within 35 min in a single chromatographic run by the elution with acetonitrile-water (26:74 or 30:70, v/v). By repetitive injection of the enriched target fraction onto the preparative column, 33 g icariin as well as 4.6 g epimedin C, 3.7 g epimedin B, and 0.6 g epimedin A were obtained from 300 g crude extract. The purities of all products were greater than 98%. This pilot-scale preparative HPLC technique and the two step separation technology for 4 target compounds are quite useful for the production of the reference standard series with good purity like icariin, epimedins A, B, C standards due to its high performance, rapid separation and more amounts of products obtained.

A new method for isolation of gentiopicroside (GPS) from Swertia mussotii Franch with reversed phase preparative high performance liquid chromatography (Pre-HPLC) is described. After 95% ethanol extract was obtained with solvent extraction and macroporous resin separation, a fraction containing GPS was acquired and subjected to Pre-HPLC for isolation of target component. The optimum operation parameters were selected as follows: a C18 column (200 mm x 50 mm, 5 microm), methanol-0.1% acetic water (30:70, v/v) as the mobile phase at flow rate of 75 mL/min, the detection wavelength at 254 nm, and the injection volume of 500 microL at the mass concentration of 225 g/L. The purity of the product was detected by HPLC method. The result showed that the purity of product was above 99%. The effective and rapid method has been successfully applied to the preparation of GPS from Swertia mussotii Franch.

Preparative high performance liquid chromatography (HPLC) are widely used recently. The optimization of its operating conditions is important for improving efficiency and saving operating cost. Now, most works such as linear scale up technology were focused on the optimization of mobile phase. The sample collection region is another important operating parameter in preparative HPLC. In this study, a software was written according to the exponentially modified Gaussian (EMG) model. With this software, the operators of preparative HPLC can easily choose a suitable sample collection region.

To identify chlorogenic acids in Helianthus tuberosus Linn leaves, a method of high performance liquid chromatography-ultraviolet-mass spectrometry (HPLC-UV-MS) was developed. HPLC analysis was performed on an Inertsil ODS-3 column (250 mm x 4.6 mm, 5 microm). The mobile phase consisted of 1% acetic acid (A) and methanol (B). A gradient program was adopted as follows: 0 - 10 min, 20% B to 35% B; 10 - 25 min, 35% B to 50% B; 25 - 35 min, 50% B to 80% B. The flow rate was set at 1.0 mL/min and the column temperature was 35 degrees C. HPLC chromatogram was extracted at 327 nm. The mass spectrometer used was a TSQ triple quadrupole MS equipped with an electrospray ionization (ESI) interface. Initially, the mass spectrometer was programmed to perform full scan ranging from m/z 250 - 1 200. For MS/MS, negative ion monitoring mode was used and the collision energy was set at 10 - 45 eV. By analyzing UV characteristics and MS fragmentation patterns, 7 chlorogenic acids were assigned to be three categories, i. e., three caffeoylquinic acids, one feruloylquinic acid and three dicaffeoylquinic acids. As the results of the method development efforts, an effective and fast method for the qualitative identification of the chlorogenic acids in Helianthus tuberosus Linn leaves was established.

A high performance liquid chromatographic (HPLC) method was successfully used to separate asiaticoside and madecassoside from the extract of Centella asiatica (L.) Urb. The raw material containing 20% asiaticoside and 45% madecassoside was dissolved in methanol and used for the preparation of the pure compounds. The flow rate of the mobile phase, injection volume and detection wavelength were optimized. The optimum operation parameters were then selected as follows: a C18 column (50 mm x 200 mm, 5 microm) with methanol-water (60 : 40, v/v) as the mobile phase at a flow rate of 100 mL/min, the detection wavelength of 220 nm, and the injection volume of 1.5 mL at the concentration of 40 mg/mL. Asiaticoside and madecassoside the can be obtained in a 20 min runtime, and the purities of the products were detected by melting point, thin layer chromatography (TLC) and HPLC method. The results showed that the purities of products were above 98%. The effective and rapid method has been successfully applied and to the preparation of asiaticoside and madecassoside from Centella asiatica (L. ) Urb.

Objective: To evaluate the efficacy of thrombolytic therapy with urokinase and/or anticoagulant with low molecular weight heparin in patients with acute pulmonary embolism., Methods: 127 patients with documented acute pulmonary embolism were treated with different regimens: thrombolysis combined with anticoagulant therapy in 70 cases, thrombolytic therapy alone in 31 cases and pure anticoagulant therapy in 26 cases., Results: Dyspnea was the most common symptom (91.3%), then cough (74.0%), chest pain (63.0%) and syncope (21.3%). As compared with pre-treatment in each group, there was significant improvement in respiratory rate, heart rate, partial pressure of oxygen in artery and partial pressure of carbon dioxide in artery. The effective rate of thrombolysis combined with anticoagulant therapy, thrombolytic therapy and anticoagulant therapy were 90.0%, 77.4% and 61.5%, respectively, the total effective rate of thrombolytic therapy was 86.1%. The best efficacy was demonstrated in patients within one week after onset of symptoms. The therapy might be effective for cases with duration longer than two weeks after the onset of symptoms., Conclusion: Thrombolytic therapy with urokinase combined with low molecular weight heparin is effective and safe for acute pulmonary embolism.