如何上好药学物理化学实验课

药学物理化学是一门理论性极强的课程,为了更好地理论联系实际,让学生对知识面有一个从感性到理性的认识,物化实验课起着举足轻重的作用.它不仅对理论课起辅助作用,而且通过实验,提高了学生的动手能力,发挥了学生的主观能动性.上好物化实验课在整个物化教学中是一个很重要的环节.如何才能上好物化实验课,通过几年的教学,得出了一套适用于实验教学的经验.

Issues in Freeze Drying of Aqueous Solutions

Freeze drying or lyophilization of aqueous solutions is widely used in pharmaceutical industry. The in-creased importance Of the process is gaining a worldwide interest of research. A growing body of literature has demonstrated that the scientific approach can result in improved product quality with minimum trial and error em-piricism. Formulation and process development need a systematical understanding of the physical chemistry of freezing and freeze drying, material science and mechanisms of heat and mass transfer. This paper presents an overview on freeze ding of aqueous solutions based on publications in the past few decades. The important issuesof the process are analyzed.

Ethnobotany, Pharmacology and Chemistry of Medicinal Orchids from Veracruz

Orchidaceae is a large family of 1,260 species in Mexico, of which 433 grow in the state of Veracruz, Mexico. Although economically important in horticulture because of the beauty of their flowers, researches have done little work regarding their medicinal properties. This paper aimed to present the results of ethnobotanical, pharmacological and active compounds research on Veracruz medicinal orchids. The ethnobotanical information was obtained by consulting the Atlas of the Mexican Traditional Medicine Plants, Veracruz Medicinal Flora Database （CITRO-UV project） and through field work in the Nahuatl community of Cuautlajapa, Veracruz. To obtain pharmacological and active compounds information of registered species, a search was carded out through MEDLINE （USA National Library of Medicine Journal Citation database）. Twelve medicinal orchids were recorded for Veracruz, i.e., Epidendrum chlorocorymbos Schltr., Habenaria floribunda Lindl., Isochillus latibracteatus A. Rich. ＆ Galeotti, lsochillus major Schltdl. ＆ Cham., Mormodes maculata var. unicolor （Hook.） L. O. Williams, Oestlundia luteorosea （A. Rich. ＆ Galeotti） W. E. Higgins, Oncidium ascendens Lindl., Scaphyglottis fasciculata Hook., Sobralia macrantha Lindl., Spiranthes eriophora （Rob. ＆ Greenm.）, Stanhopea oculata （G. Lodd.） Lindl. and Vanilla planifolia Andrews. Only two species have been investigated in terms of their pharmacology and active compounds. Also, information for another five species closely related to already identified ones was obtained. Given the relative poverty of current information on the topic, this paper demonstrates the need to further study the ethnobotanical, pharmacological and chemical aspects of the region＇s medicinal orchids.

Phytochemistry and pharmacology of genus Ephedra

The genus Ephedra of the Ephedraceae family contains more than 60 species of nonflowering seed plants distributed throughout Asia, America, Europe, and North Africa. These Ephedra species have medicinal, ecological, and economic value. This review aims to summarize the chemical constituents and pharmacological activities of the Ephedra species to unveil opportunities for future research. Comprehensive information on the Ephedra species was collected by electronic search(e.g., GoogleScholar, Pubmed, Sci Finder, and Web of Science) and phytochemical books. The chemical compounds isolated from the Ephedra species include alkaloids, flavonoids, tannins, polysaccharides, and others. The in vitro and in vivo pharmacological studies on the crude extracts, fractions and few isolated compounds of Ephedra species showed anti-inflammatory, anticancer, antibacterial, antioxidant, hepatoprotective, anti-obesity, antiviral, and diuretic activities. After chemical and pharmacological profiling, current research is focused on the antibacterial and antifungal effects of the phenolic acid compounds, the immunosuppressive activity of the polysaccharides, and the antitumor activity of flavonoids.

Tetrandrine inhibits migration and invasion of rheumatoid arthritis fibroblast-like synoviocytes through down-regulating the expressions of Rac1, Cdc42, and Rho A GTPases and activation of the PI3K/Akt and JNK signaling pathways

Tetrandrine （Tet）, the main active constituent of Stephania tetrandra root, has been demonstrated to alleviate adjuvant-induced arthritis in rats. The present study was designed to investigate the effects of Tet on the migration and invasion of rheumatoid arthritis fibroblast-like synovioeytes （RA-FLS） and explore the underlying mechanisms. By using cultures of primary FLS isolated from synoviums of RA patients and cell line MH7A, Tet （0.3, 1 μmol L-1） was proven to significantly impede migration and invasion of RA-FLS, but not cell proliferation. Tet also greatly reduced the activation and expressions of matrix degrading enzymes MMP-2/9, the expression of F-actin and the activation of FAK, which controlled the morphologic changes in migration process of FLS. To identify the key signaling pathways by which Tet exerts anti-migration effect, the specific inhibitors of multiple signaling pathways LY294002, Triciribine, SP600125, U0126, SB203580, and PDTC （against PI3K, Akt, JNK, ERK, p38 MAPK and NF-kB-p65, respectively） were used. Among them, LY294002, Triciribine, and SP600125 were shown to obviously inhibit the migration of MH7A cells. Consistently, Tet was able to down-regulate the activation of Akt and JNK as demonstrated by Western blotting assay. Moreover, Tet could reduce the expressions of migration-related proteins Rho GTPases Rac 1, Cdc42, and RhoA in MH7A cells. In conclusion, Tet can impede the migration and invasion of RA-FLS, which provides a plausible explanation for its protective effect on RA. The underlying mechanisms involve the reduction of the expressions of Racl, Cdc42, and RhoA, inhibition of the activation of Akt and JNK, and subsequent down-regulation of activation and/or expressions of MMP-2/9, F-actin, and FAK.

Tongqiao Huoxue Decoction ameliorates learning and memory defects in rats with vascular dementia by up-regulating the Ca^(2+)-CaMKII-CREB pathway

The present study was aimed at determining the effects of Tongqiao Huoxue Decoction （TQHXD） on the Ca2＋-CaMKII-CREB pathway and the memory and learning capacities of rats with vascular dementia （VD）. The rat VD model was established by using an improved bilateral carotid artery ligation method. The Morris water maze experiment was used to evaluate the ethology of the VD rats following treatments with TQHXD at 3.01, 6.02, and 12.04 g.kg-1 per day for 31 days. At the end of experiment, the hippocampus were harvested and analyzed. Western blotting and RT-PCR were used to measure the expression levels of calmodulin-binding protein kinase II（CaMKII）, protein kinase A（PKA）, cAMP-response element binding protein（CREB）, and three N-methyl-D-aspart^c acid receptor subunits （NR1, NR2A, and NR2B）. Our results revealed that TQHXD could alleviate the loss of learning abilities and increase the memory capacity （P 〈 0.05 and P 〈 0.01 vs the model group, respectively）. The treatment with 6.02 and 12.04 g.kg-1 of TQHXD significantly up-regulated the Ca2＋-CaMKII-CREB pathway in the hippocampus. In conclusion, TQHXD showed therapeutic effects on a bilateral carotid artery ligation-induced vascular dementia model, through the up-regulation of calcium signalling oathwavs.

Simultaneous quantification of ten constituents of Xanthoceras sorbifolia Bunge using UHPLC-MS methods and evaluation of their radical scavenging, DNA scission protective, and α-glucosidase inhibitory activities

The present study was designed to investigate the bioactive constituents ofXanthoceras sorbifolia in terms of amounts and their antioxidant, DNA scissiou protection, and ct-glucosidase inhibitory activities. Simultaneous quantification of 10 X. sorbifolia constituents was carried out by a newly established ultra-high performance liquid chromatography-quadrupole mass spectrometry method （UHPLC-MS）, The antioxidant activities were evaluated by measuring DPPH radical scavenging and DNA scission protective activities. The a-glucosidase inhibitory activities were investigated by using an assay with a-glucosidase from Bacillus Stearothermophilus and disaccharidases from mouse intestine. We found that the wood ofX. sorbifolia was rich in phenolic compounds with the contents of catechin, epicatechin, myricetin, and dihydromyricetin being 0.12-0.19, 1.94-2.16, 0.77-0.91, and 6.76-7.89 mg.g-1, respectively. The four constituents strongly scavenged DPPH radicals （with ECs0 being 4.2, 3.8 and 5.7 μg-mL-1, respectively） and remarkably protected peroxyl radical-induced DNA strand scission （92.10%, 94.66%, 75.44% and 89.95% of protection, respectively, at a concentration of 10 μmol.L-1）. A dimeric flavan 3-ol, epigallocatechin-（4β→8, 2β→O-7）-epicatechin potently inhibited a-glucosidase with an IC50 value being as low as 1.2 μg.mL1. The established UHPLC-MS method could serve as a quality control tool for X. sorbifolia. In conclusion, the high contents of antioxidant and α-glucosidase inhibitory constituents in X. sorbifolia support its use as complementation of other therapeutic agents for metabolic disorders, such as diabetes and hypertension.

Anti-inflammatory and anti-arthritic effects of Guge Fengtong Formula: in vitro and in vivo studies

Rheumatoid arthritis （RA） is the most common inflammatory arthritis and a major cause of disability. Presently, the clinical therapeutic medicines for inflammatory and arthritic diseases are unsatisfactory due to severe adverse effects or ineffectiveness. The Guge Fengtong formula （GGFT）, containing the standardized extracts of Dioscoreae Nipponicae Rhizoma, Spatholobi Caulis, and Zingiberis Rhizoma, has long been used for RA treatment in China. However, the detailed anti-inflammatory and anti-arthritic activity of GGFT has not been reported so far. In the present work, we aimed to evaluate the anti-inflammatory and anti-arthritic effects of GGFT using three in vivo animal models and tried to uncover the underlying mechanism of action in RAW 264.7 macrophages. The obtained results indicated that GGFT significantly attenuated ear edema, decreased carrageenan-induced paw edema, reduced the ar- thritis score, and reversed the weight loss of the complete Freund＇s adjuvant （CFA）-injected rats. Additionally, decrease in synovial inflammatory infiltration and synovial lining hyperplasia in the joints and decline of inflammatory factors （TNF-α and IL-1β） in the serum were observed in the GGFT-treated rats. In lipopolysaccharide-activated RAW264.7 macrophages, GGFT reduced the produc- tion of NO, PGE2, and IL-6 and inhibited the expression of iNOS, COX-2, and NF-kB. Our results demonstrated that GGFT possessed considerable anti-inflammatory activity and had potential therapeutic effects on adjuvant induced arthritis in rats, providing experi- mental evidences for its application in the treatment of RA and other inflammatory diseases.

Ethanolic extract of dandelion(Taraxacum mongolicum) induces estrogenic activity in MCF-7 cells and immature rats

Plants of the genus Taraxacum, commonly known as dandelions, are used to treat breast cancer in traditional folk medicine. However, their use has mainly been based on empirical findings without sufficient scientific evidence. Therefore, we hypothesized that dandelions would behave as a Selective estrogen receptor modulator （SERM） and be effective as hormone replacement therapy （HRT） in the postmenopausal women. In the present study, in vitro assay systems, including cell proliferation assay, reporter gene assay, and RT-PCR to evaluate the mRNA expression of estrogen-related genes （pS2 and progesterone receptor, PR）, were performed in human breast cancer cells. Dandelion ethanol extract （DEE） significantly increased cell proliferation and estrogen response element （ERE）-driven luciferase activity. DEE significantly induced the expression of estrogen related genes such as pS2 and PR, which was inhibited by tamoxifen at 1 gmol L-1. These results indicated that DEE could induce estrogenic activities mediated by a classical estrogen receptor pathway. In addition, immature rat uterotrophic assay was carried out to identify estrogenic activity of DEE in vivo. The lowest concentration of DEE slightly increased the uterine wet weight, but there was no significant effect with the highest concentration of DEE. The results demonstrate the potential estrogenic activities of DEE, providing scientific evidence supporting their use in traditional medicine.

Cancer therapy using natural ligands that target estrogen receptor beta

Estrogen receptor beta(ERβ) is one of the two key receptors(ERα, ERβ) that facilitate biological actions of 17β-estradiol(E2). ERβ is widely expressed in many tissues, and its expression is reduced or lost during progression of many tumors. ERβ facilitates estrogen signaling by both genomic(classical and non-classical) and extra-nuclear signaling. Emerging evidence suggests that ERβ functions as a tissue-specific tumor suppressor with anti-proliferative actions. Recent studies have identified a number of naturally available selective ERβ agonists. Targeting ERβ using its naturally available ligands is an attractive approach for treating and preventing cancers. This review presents the beneficial actions of ERβ signaling and clinical utility of several natural ERβ ligands as potential cancer therapy.

The importance of start codon of nosM in nosiheptide production

The present study was designed to investigate the effects of start codon of nosM on the biosynthesis of nosiheptide. Target genes were amplified by overlap PCR. After homologous recombination to construct engineered strains, nosiheptide production was analyzed by HPLC. Three mutants with different start codon ofnosMwere constructed, and nosihcptide production of each mutant was analyzed and compared. Replacement of the start eodon of nosM significantly decreased the production of nosiheptide. In conclusion, start codon usage could greatly affect the biosynthetic efficiency in the biosynthetic gene cluster of nosiheptide.

Preparation and physicochemical characterization of a solid dispersion of(3, 5, 6-trimethylpyrazin-2-yl) methyl 3-methoxy-4-[(3, 5, 6-trimethylpyrazin-2-yl) methoxy] benzoate(VA-T) and polyvinylpyrrolidone

Ischemic brain injury is a major disease which threatens human health and safety.(3, 5, 6-trimethylpyrazin-2-yl) methyl 3-methoxy-4-[(3, 5, 6-trimethylpyrazin-2-yl) methoxy] benzoate(VA-T), a newly discovered lead compound, is effective for the treatment of ischemic brain injury and its sequelae. But the poor solubility of VA-T leads to poor dissolution and limited clinical application. In order to improve the dissolution of VA-T, the pharmaceutical technology of solid dispersions was used in the present study. VA-T/ polyvinylpyrrolidone(PVP) solid dispersion was prepared by the solvent method. The dissolution studies were carried out and solid state characterization was evaluated by differential scanning calorimetry(DSC), infrared spectroscopy(IR), x-ray diffraction(XRD) and scanning electron microscopy(SEM). The dissolution rate of VA-T was significantly improved by solid dispersion compared to that of the pure drug and physical mixture. The results of DSC and XRD indicated that the VA-T solid dispersion was amorphous. The IR spectra showed the possible interaction between VA-T and PVP was the formulation of hydrogen bonding. The SEM analysis demonstrated that there was no VA-T crystal observed in the solid dispersions. The ideal drug-to-PVP ratio was 1 : 5. In conclusion, the solid dispersion technique can be successfully used for the improvement of the dissolution profile of VA-T.

Pharmacodynamics and potential synergistic effects of Mai-Luo-Ning injection on cardiovascular protection, based on molecular docking

As a computer-assisted approach, molecular docking has been universally applied in drug research and development and plays an important role in the investigation and evaluation of herbal medicines. Herein, the method was used to estimate the pharmacodynamics of Mai-Luo-Ning injection, a traditional Chinese compound herbal prescription. Through investigating the interactions between several important proteins in cardiovascular system and characteristic components of the formula, its effect on cardiovascular protection was evaluated. Results showed the differences in the interactions between each component and the selected target proteins and revealed the possible mechanisms for synergistic effects of various characteristic components on cardiovascular protection. The study provided scientific evidence supporting the mechanistic study of the interactions among multi-components and targets, offering a general approach to investigating the pharmacodynamics of complicated materials in compound herbal prescriptions.

Statistical optimization and in vivo evaluation of colon specific delivery system of herbal rhubarb extract

The present research effort was aimed to develop colon targeted drug delivery system(CTDDS)of rhubarb,herbal drug using a mixed film of pectin and ethyl cellulose(EC).Pectin and ethyl cellulose were mixed in various proportions to coat the core tablet to target colon.The methanolic extract of rhubarb was used and the dose of the extract in each formulation was finalized by estimating the emodin content in it by high performace thin layer chromatography(HPTLC).In vitro drug release,erosion study in presence and absence of pectinase enzyme and release constant(K)of zero order was measured for each formulation.The formulation was optimized by using 32full factorial design.Formulation having 50%pectin as a coating polymer with12%coat weight was selected as an optimized formulation(OF)on the basis of%similarity with maximum desirability but this formulation was not able to retard the release of drug in stomach and upper intestine fully.So it was further coated with Eudragit S100(ES)(3%coat weight).The optimized formulation,coated with ES indicated significant laxative activity on loperamide induced constipation in rats.The results revealed that CTDDS of rhubarb using two combined approaches of biodegrable microflora-activated system and pH-sensitive system exhibited a promising colon targeting performance.

Elucidation of the fragmentation pathways of a complex 3,7-O-glycosyl flavonol by CID, HCD, and PQD on an LTQ-Orbitrap Velos Pro hybrid mass spectrometer

The present study was designed to systematically investigate the ESI-MSn behavior of a complex 3, 7-O-glycosyl flavonol, kaempferol 3-O-α-L-[2,3-di-O-β-D-（6-E-p-coumaroyl）glucopyranosyl]-rhamnopyranosyl-7-O-α-L-rhamnopyranoside （KO） isolated from Epimedium wushanense, and to address the elimination priority among different glycosylation sites and different sugars/substituents. The direct-infusion ESI-MSn experiment of KO was performed on a hybrid LTQ-Orbitrap Velos Pro mass spectrometer in both negative and positive ion modes by three different fragmentation mechanisms （CID, HCD, and PQD）. The CID, HCD, and PQD analyses of KO exhibited remarkable discrimination in respect of the scan range, richness, and distribution of product ions through the entire spectra. KO experienced different fragmentation pathways between two ionization modes： the negative mode CID of KO eliminated the glycosyl portions （priority： 7-sugar 〉 3-substituent and terminal substituents 〉 inner sugar） and produced aglycone product ions at m/z 284.03/285.04; however, abundant sodium-adduct B32 together with subsequent ijX30 cleavages were found characteristic for the positive mode CID-MSn. The fragmentation pathways by CID for KO were proposed by analyzing the high accuracy ESI-MS＂ data. Complementary structural information of KO regarding the aglycone and glycosyl portions was obtained by analyzing the ESI-MSn data in both ionization modes. In conclusion, the LTQ-Orbitrap method facilitates highly reliable qualitative analysis of bioactive flavonoids with three alternative fragmentation modes.

Sensitive method for rapid estimation of Lornoxicam in bulk and its dosage form by RP-HPLC

Lornoxicam (6-chloro-4-hydroxy-2-methyl-N-2-pyridyl-2H-thieno-[2,3-e]-1,2-thiazine-3-carboxamide-1,1-dioxide) is persist as a non-steroidal anti-inflammatory drug of the oxicam class with analgesic, anti-inflammatory and antipyretic properties. A fast, accurate and sensitive chromatographic method for estimation of Lornoxicam was developed as no official method available for detection. The chromatographic separation employs isocratic elution by utilizing an inertsil ODS-C 18 , 250 mm×4.6 mm, 5 μm columns. Mobile phase consisting of solvent (40 mL acetonitrile and 60 mL 0.1 M phosphate buffer (pH 6.8 was adjusted with triethylamine)) endowed at a flow rate of 1.0 mL/min. The analyte was detected and quantified at 290 nm using UV detector. The method was validated according to ICH guidelines, illustrating to be accurate (recovery 99.08%-101.13%) and precise (intraday (0.27-1.32) and interday (0.59-1.59))within the corresponding linear range (10-60 μg/mL) with r 2 0.9992.