Improving ocular bioavailability of hydrophilic drugs through dynamic covalent complexation.

The clinical benefits of diquafosol tetrasodium (DQS), a hydrophilic P2Y2 receptor agonist for dry eye, have been hindered by a demanding dosing regimen. Nevertheless, it is challenging to achieve sustained release of DQS with conventional drug delivery vehicles which are mainly designed for hydrophobic small molecule drugs. To address this, we developed an affinity hydrogel for DQS by taking advantage of borate-mediated dynamic covalent complexation between DQS and hydroxypropyl guar. The resultant formulation (3% DQS Gel) was characterized by sustained release, low corneal permeation, and extended ocular retention, which were desirable attributes for ocular surface drug delivery. Both in vitro and in vivo studies had been carried out to verify the biocompatibility of 3% DQS Gel. Using corneal fluorescein staining, the Schirmer's test, PAS staining, quantitative PCR and immunohistological analyses as outcome measures, the superior therapeutic effects of 3% DQS Gel over PBS, the hydrogel vehicle and free DQS were demonstrated in a mouse dry eye model. Our DQS delivery strategy reported herein is readily applicable to other hydrophilic small molecule drugs with cis-diol moieties, thus providing a general solution to improve clinical outcomes of numerous diseases.

Enhanced analytical performance of disposable 3D carbon electrodes prepared with stainless steel wire mesh.

This paper aims to use low-cost stainless steel wire mesh (SSWM) as uniform templates to prepare disposable three-dimensional (3D) carbon electrodes to improve their analytical performance. Native SSWM electrodes were prepared with lamination and then coated with carbon cement for bulk preparation of disposable 3D carbon electrodes with drop-casting. The electrodes were then coupled in paper-based analytical devices. Meanwhile, disposable 2D carbon electrodes were prepared with the stainless steel sheets (SSSs) for comparison under the same condition using stripping analysis of heavy metals as a model. Our results demonstrated that the sensitivity of the 3D carbon electrodes was about three times as high as that of the 2D carbon electrodes on stripping analysis of both heavy metals. The electrochemical responses of 1 µg L-1 Pb2+ at the 3D carbon electrodes were about 6 times as high as those at the 2D carbon electrodes. The improved analytical performance of disposable 3D carbon electrodes could be attributed to their increased electrochemical effective area, which was brought by replacing SSSs with SSWM. The obtained disposable 3D carbon electrodes could be used for differentiation of Pb in teethers and corns. This study not only presented the potential of SSWM in the preparation of disposable 3D carbon electrodes but also suggested a simple and effective strategy for the preparation of disposable 3D electrodes for practical applications.

New glycosylsphingolipids from Psychotria serpens L.

In clinical, Psychotria serpens L. was often substitute for Caulis trachelospermi to treat cancer in China. Meanwhile, EtOAc and n-BuOH fractions of MeOH extract of P. serpens L. show power activity against H460, HepG2, Hela, and PC9/GR cell lines, and no toxic effects against normal 16HBE cell lines. In our ongoing search for bioactive novel compounds from Chinese material medica, one new type of glycosylsphingolipids Psychotramide (1a-1c) were isolated from P. serpens L., and their structures were identified through spectroscopic techniques including NMR (1D and 2D) and MS (LC-MS, and GC-MS).

Paper-based electroanalytical devices for stripping analysis of lead and cadmium in children's shoes.

Children's shoes are potential sources of toxic heavy metals, especially for younger children. Electrochemical detection could be applied for effective stripping analysis of heavy metals (such as Cd and Pb). However, the substrates of working electrodes are still limited and it is not well known which property is critical. Herein ITO glass was used as the substrate and the working electrode was modified with carbon cement for stripping analysis of Cd and Pb. The electrochemical impedance spectra of the ITO modified electrodes suggested the connection between the resistance and the electrochemical responses of heavy metals in stripping analysis, depending on the dilution ratio of the carbon cement. After optimization, the ITO modified electrodes in paper-based analytical devices could be used to sensitively quantify Cd and Pb with the concentration ranging from 10 to 1000 ppb. The detection limit of Pb2+ could reach less than 1 ppb while that of Cd2+ could reach 5 ppb, depending on the pH value of the sample solution. The paper-based electroanalytical devices could be used to quantify the concentration of Cd and Pb in children's shoes. This study implied the impact of the electric conductivity of the electrode substrates on stripping analysis, which might help to find more materials for the fabrication of the working electrodes.

Whole exome sequencing identifies a rare variant in DAAM2 as a potential candidate in idiopathic pulmonary ossification.

BACKGROUND: Diffuse pulmonary ossification (DPO) is a rare disease characterized by bone tissue formation in the lung. DPO can be classified into idiopathic pulmonary ossification (IPO) and secondary pulmonary ossification. Cases with no identified etiology are classified as IPO. Variants of dishevelled associated activator of morphogenesis 2 (DAAM2) have been reported to be involved in the bone-resorption of osteoclasts. METHODS: Whole exome sequencing (WES) was used on samples from a patient with IPO and his healthy parents. The effects of all variants were determined using functional predictors (PolyPhen-2, SIFT, FATHMM and MutationTaster); variants existing only in the patient were further screened compared with his healthy parents. RESULTS: Forty deleterious variants, including 25 single nucleotide variants (SNVs) and 15 insertions and deletions (indels), were identified by WES. Finally, DAAM2 (c.G2960T:p.R987L) was screened by pathway analysis. CONCLUSIONS: We identified a novel variant of DAAM2 (c.G2960T:p.R987L) that might participate in the disease process of IPO.

New amide alkaloids from Delphinium brunonianum.

Five new amide alkaloids, named delamide A-E (1-5), along with five known ones, methyl-N-(3-carboxy-2-methylpropanoyl) anthranilate (6), benzoic acid, 2-[(1-oxodecyl) amino]-methylester (7), puberline (8), benzoic acid, 2-[(4-methoxy-2-methyl-1, 4-dioxobutyl) amino]-methylester (9) and benzoic acid, 2-[(4-methoxy-3-methyl-1, 4-dioxobutyl) amino]-methylester (10) were isolated from the extract of Delphinium brunonianum. Their structures were elucidated by extensive spectroscopic analyses (including 1D-, 2D-NMR, and HR-ESI-MS). 1-10 were also evaluated for their acetylcholinesterase (AChE) inhibiting activity by the Ellman's method. Delamide A (1) showed highly selective AChE inhibition activity. The kinetic analysis revealed that 1 was a mixed-type reversible inhibitor of AChE.

Low-risk gestational trophoblastic neoplasia outcome after treatment with VMP regimen from 2005 to 2017.

OBJECTIVE: To evaluate the efficacy and toxicity of VMP regimen applied to the patients with low-risk gestational trophoblastic neoplasia (LR-GTN) treated in Anhui provincial hospital. MATERIALS AND METHODS: Between 2005 and 2017, 87 patients with low-risk gestational trophoblastic neoplasia received VMP regimen, consisted of vincristine (VCR), methotrexate (MTX) and platinum (cisplatin, carboplatin or nedaplatin), 68 of whom received VMP as their first-line chemotherapy, and 19 methotrexate-failed patients received VMP regimen as their second-line chemotherapy. The staging and scoring system was based on International Federation of Gynecology and Obstetrics (FIGO 2000) criteria. We describe and analyze their baseline characteristics, remission/resistance/recurrence rates, adverse reactions and prognosis. RESULTS: The first-line VMP protocol can achieve an 83.8% remission rate and it tended to develop resistance when the pretreatment ß-hCG reaches 7503.5 IU/L, and can achieve complete remission with FAV and EMA-CO as the salvage regimen. Among the 19 methotrexate-failed patients, 2 of whom were yet resistant to VMP regimen, followed by several courses of salvage chemotherapy such as FAV and EMP, and achieved 89.5% remission rate in second-line VMP group. Resistance to this regimen was obviously related with higher pre-treatment HCG whether used as primary or salvage treatment. Severe myelosuppression (grade 3 or 4) was shown in 4 (5.9%) of 68 cases, of which none was grade 4. CONCLUSION: For patients diagnosed with LR-GTN VMP regimen was a safe and effective treatment with a high rate of remission.

BAMBI regulates macrophages inducing the differentiation of Treg through the TGF-ß pathway in chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterized by continuous flow limitation and the immune system including macrophages and regulatory T lymphocytes (Tregs) is involved in COPD pathogenesis. In our previous study, we investigated that TGF-ß/BAMBI pathway was associated with COPD by regulating the balance of Th17/Treg. However, the role of bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI), a pseudoreceptor of TGF-ß signalling pathway, in regulating the immune system of COPD patients has not been fully studied. Hence, we speculate that the pseudoreceptor BAMBI may play roles in the regulation of M2 macrophages to induce the differentiation of CD4+ naïve T cells into Tregs and influence the immune response in COPD. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from healthy nonsmokers (n = 12), healthy smokers (n = 10) and COPD patients (n = 20). Naïve CD4+ T cells and monocytes-induced macrophages were used for coculture assays. The phenotypic characteristics of macrophages and Tregs were determined by flow cytometry. The expression levels of BAMBI and the TGF-ß/Smad pathway members in M2 macrophages were measured by a Western blot analysis. The monocyte-derived macrophages were stimulated with cigarette smoke extract (CSE, concentration of 0.02%) to simulate the smoking process in humans. pCMV-BAMBI was transfected into monocyte-derived M2 macrophages for subsequent co-culture assays and signalling pathway analysis. RESULTS: Our results showed that M2 macrophages could induce the differentiation of Tregs through the TGF-ß/Smad signalling pathway. In addition, monocyte-derived macrophages from COPD patients highly expressed BAMBI, and had a low capacity to induce Tregs differentiation. The expression of BAMBI and the forced expiratory volume in 1 second (FEV1%) were negatively correlated in COPD. Furthermore, overexpression of BAMBI promoted the conversion of M2 macrophages to M1 macrophages via the TGF-ß/Smad pathway. CONCLUSIONS: We demonstrated that BAMBI could promote the polarization process of M2 macrophages to M1 macrophages via the TGF-ß/Smad signalling pathway and that overexpression of BAMBI could decrease the ability of M2 macrophages to induce Treg differentiation. These findings may provide a potential mechanism by which blocking BAMBI could improve immune function to regulate COPD inflammatory conditions.

Identification and Pharmacokinetic Studies on Complanatuside and Its Major Metabolites in Rats by UHPLC-Q-TOF-MS/MS and LC-MS/MS.

The metabolic and pharmacokinetic studies on complanatuside, a quality marker of a Chinese materia medicatonic, Semen Astragali Complanati, were carried out. The UHPLC-Q-TOF/MS (ultra-high performance liquid chromatography coupled with electrospray ionization tandem quadrupole-time-of-flight mass spectrometry) method was applied to identify the metabolites of complanatuside in rat plasma, bile, stool, and urine after oral administration at the dosage of 72 mg/kg. Up to 34 metabolites (parent, 2 metabolites of the parent drug, and 31 metabolites of the degradation products) were observed, including processes of demethylation, hydroxylation, glucuronidation, sulfonation, and dehydration. The results indicated glucuronidation and sulfonation as major metabolic pathways of complanatuside in vivo. Meanwhile, a HPLC-MS method to quantify complanatuside and its two major metabolites-rhamnocitrin 3-O-ß-glc and rhamnocitrin-in rat plasma for the pharmacokinetic analysis was developed and validated. The Tmax (time to reach the maximum drug concentration) of the above three compounds were 1 h, 3 h, and 5.3 h, respectively, while the Cmax (maximum plasma concentrations)were 119.15 ng/mL, 111.64 ng/mL, and 1122.18 ng/mL, and AUC(0-t) (area under the plasma concentration-time curve) was 143.52 µg/L·h, 381.73 µg/L·h, and 6540.14 µg/L·h, accordingly. The pharmacokinetic characteristics of complanatuside and its two metabolites suggested that complanatuside rapidly metabolized in vivo, while its metabolites-rhamnocitrin-was the main existent form in rat plasma after oral administration. The results of intracorporal processes, existing forms, and pharmacokinetic characteristics of complanatuside in rats supported its low bioavailability.

Qualitative and Quantitative Analysis of the Major Constituents in WLJ Herbal Tea Using Multiple Chromatographic Techniques.

Quality control of Chinese herbal tea remains a challenge due to our poor knowledge of their complex chemical profile. This study aims to investigate the chemical composition of one of the best-selling and famous brand of beverage in China, Wanglaoji Herbal Tea (WLJHT), via a full component quantitative analysis. In this paper, a total of thirty-two representative constituents were identified or tentatively characterized using ultra-high performance liquid chromatography coupled with quadrupole tandem time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Moreover, the quantitative analyses of fourteen constituents were performed by high performance liquid chromatography with a triple quadruple tandem mass spectrometry (HPLC-MS/MS) method and saccharide compositions of WLJHT were also quantitatively determined by high performance liquid chromatography (HPLC) with evaporative light scattering detector (ELSD) on a Hilic column, separately. Using multiple chromatographic techniques presented a good precision, sensitivity, repeatability and stability, and was successfully applied to analyze 16 batches of WLJHT samples. Therefore, it would be a reliable and useful approach for the quality control of WLJHT.

Simultaneous qualitative and quantitative evaluation of Ilex kudingcha C. J. tseng by using UPLC and UHPLC-qTOF-MS/MS.

In this study, a systematic method was established for the holistic quality control of Ilex kudingcha C. J. Tseng, a popular functional drink for adjuvant treatment of diabetes, hypertension, obesity and hyperlipidemia. Both qualitative and quantitative analyses were conducted. For qualitative analysis, an ultra high performance liquid chromatography (UHPLC) coupled with an electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-qTOF-MS) method was established for rapid separation and structural identification of the constituents in Ilex kudingcha. Samples were separated on an ACQUITY UPLC HSS T3C18 column (2.1 mm × 100 mm, 1.8 µm) by gradient elution using 0.1% (v/v) formic acid (solvent A) and acetonitrile (solvent B) as mobile phases at a flow rate of 0.25 mL min-1. The chromatographic profiling of Ilex kudingcha by UHPLC-qTOF-MS/MS resulted in the characterization of 53 compounds, comprising 18 compounds that were unambiguously identified by comparison with reference standards. For quantitative analysis, 18 major compounds from 15 batches of Ilex kudingcha samples were simultaneously detected by UPLC-DAD at wavelengths of 210 nm, 260 nm, and 326 nm. The method was validated with respect to precision, linearity, repeatability, stability, accuracy, and so on. The contents of the 18 target compounds were applied for hierarchical clustering analysis (HCA) and principal component analysis (PCA) to differentiate between the samples. The results of HCA and PCA were consistent with each other. Sample No. 1 differed significantly based on HCA and PCA, and the differentiating components were confirmed to originate from different batches of samples. Phenolic acids and triterpenes were found to be the main ingredients in Ilex kudingcha. This strategy was effective and straightforward, and provided a potential approach for holistic quality control of Ilex kudingcha.

[Interaction of phenylethanoid glycosides and calf thymus DNA].

In physiological condition, the interaction of acteoside and forsythoside B with calf thymus DNA using neutral red (NR) as a fluorescence probe were investigated by fluorescence, UV-visible spectrophotometry, viscosity, DNA melting techniques, and molecular docking. It is observed that acteoside and forsythoside B can react with DNA. The major mode of recognition between drug and DNA is groove binding by hydrogen bonds, and the interaction of acteoside with DNA is stronger than that of forsythoside B.

A new diterpenoid alkaloid isolated from Delphinium caeruleum.

The present study was designed to determine the chemical constituents of Delphinium caeruleum Jacq. ex Camb.. The chemical constituents were isolated and purified by column chromatography with silica gel, ODS, and Sephadex LH-20. Their structures were elucidated by IR, MS, and NMR. Ten compounds were obtained and identified as caerudelphinine A (1), lycoctonine (2), talitine B (3), talitine A (4), talitine C (5), tatsienine-V (6), d-magnoflorine (7), 2-trimethyl-ammonio-3-(3-indolyl) propionate (8), vakhmatine (9), and delatisine (10). Compound 1 was a new lycoctonine-type C19-diterpenoid alkaloid, and compounds 4-10 were isolated from this plant for the first time.

Cytotoxic diterpenoids from Rabdosia lophanthoides var. gerardianus.

Two new abietane diterpenoids, Gerardianin B (1) and Gerardianin C (2), one new lignan glycoside, Gerardianin D (3) and one new lupane-type triterpenoid, Gerardianol A (4), together with seven known abietane diterpenoids were isolated from the aerial parts of Rabdosia lophanthoides var. gerardianus. Their structures were determined by 1D and 2D NMR spectroscopic data. The cytotoxic activities of the nine diterpenoids were evaluated on human cancer cell lines. Compounds 6-11 exhibited significant cytotoxic activities against HepG2 cell lines with IC50 from 4.68 to 9.43µM and HCF-8 cell lines with IC50 from 9.12 to 13.53µM.

[HPLC Fingerprints of Nerviliae fordii and Nervilia plicata].

OBJECTIVE: To establish the HPLC fingerprint of the whole plant of Nerviliae fordii and Nervilia plicata, in order to provide a method for evaluation of authenticity and quality control of the whole plant of Nerviliae fordii. METHODS: 15 batches of Nerviliae fordii and 5 batches of Nervilia plicata were analyzed on a Kromasil C18 column (250 mm x 4.6 mm, 5 µm) at room temperature with gradient elution using acetonitrile and 0.2% phosphoric acid as the mobile phase at a flow rate of 1.0 mL/min. The wavelength of detector was 256 nm. RESULTS: Significant differences were found between Nerviliae fordii and Nervilia plicata. Furthermore, there were no obvious differences observed between Nerviliae fordii of big-leaf and Nerviliae fordii of small-leaf. CONCLUSION: The present-developed HPLC fingerprints method provides a rapid, effective and valuable benchmark for distinguishing of Nerviliae fordii and Nervilia plicata, which is favorable to improve overall quality control of Nerviliae Fordii.

[Simultaneous determination of 4 alkaloids and a flavonoid in Picrasmae Ramulus et Folium by RP-HPLC].

A RP-HPLC method was developed to evaluate the quality of Picrasmae Ramulus et Folium by simultaneous determination of five constituents including 1-hydroxymethyl-beta-carboline (1), 1-methoxicabony-beta-carboline (2), 4-methoxy-5-hydroxy-canthin-6-one (3), 4, 5-dimethoxy-canthin-6-one (4) and maackiain (5) in Picrasmae Ramulus et Folium. The samples were separated on a Kromasil RP-C18 (4.6 mm x 250 mm, 5 microm) column eluted with acetonitrile and 0.1% phosphoric acid as mobile phases in gradient mode. The detection wavelength was set at 254 nm. The calibration curves and linearity of the above five standards were determined as (1) Y = 6 525.6X + 37.25 (0.009-1.780 microg, r = 0.996 8), (2) Y = 3 662.3X + 41.55 (0.005-0.920 microg, r = 0.999 5), (3) Y = 3763.1X + 146.87 (0.015-3.060 microg, r = 0.999 0), (4) Y = 2 174.1X + 21.52 (0.003-0.620 microg, r = 0.999 5), and (5) Y = 276.25X + 7.65 (0.010-1.960 microg, r = 0.998 9), respectively. The method is simple and repeatable, and can be used for the quality assessment of Picrasmae Ramulus et Folium.

Diterpenoid alkaloids and flavonoids from Delphinium trichophorum.

Five hetisane-type C20-diterpenoid alkaloids, trichodelphinines A-E, one delnudine-type C20-diterpenoid alkaloid, trichodelphinine F and three known flavonoids, quercetin, quercetin 3-O-ß-D-glucopyranoside, and quercetin 3-O-ß-D-glucopyranoside-7-O-α-L-arabinopyranoside, were isolated from whole plants of Delphinium trichophorum Franch. Their structures were elucidated on the basis of extensive spectroscopic analysis, including HSQC, HMBC, (1)H-(1)H COSY, NOESY and X-ray crystallographic analysis, and from chemical evidence. The cytotoxic activities of the diterpenoid alkaloids were evaluated using the MTT method, and the IC50 values of their cytotoxicity against A549 cancer cells ranged from 12.03 to 52.79 µM.

Structure-activity relationships of antioxidant activity in vitro about flavonoids isolated from Pyrethrum tatsienense.

AIM: Antioxidant activity is one of the important indexes for estimating medicinal value for the traditional Chinese medicine. The aim of this study is to investigate the antioxidant activity of 11 flavonoids mainly revealing luteolin as mother nucleus isolated from Pyrethrum tatsienense. MATERIALS AND METHODS: The antioxidant activity of 11 flavonoids was measured in vitro using the classical 1,1-diphenyl-2-picrylhydrazyl removal method. The percentages of scavenging activity of 11 flavonoids were analyzed by taking the choice of a-tocopherol as positive drugs, and the scavenging activity was plotted against the sample concentration to obtain the IC50 values. RESULTS: Ten flavonoids containing phenolic hydroxyl groups have different levels of antioxidant activity. Antioxidant activity mainly depends on the numbers and the substitutional positions of phenolic hydroxyls in B ring. When C-3', 4' positions in B ring of flavonoids are replaced by hydroxyl groups, the antioxidant activity improved remarkably. Phenolic hydroxyl groups in A ring contribute some to antioxidant activity because of the electrophilic effect of C ring, and the numbers and substitutional positions of methoxyl and glycosyl have a little effect on the antioxidant activity. CONCLUSION: Structure-activity relationships of antioxidant activity about flavonoids isolated from P. tatsienense are concluded, which will be beneficial to deep understanding the pharmacological functions of this Tibetan medicine in vivo from the point of antioxidation.

Investigation on the differences of four flavonoids with similar structure binding to human serum albumin.

Flavonoids are structurally diverse and the most ubiquitous groups of polyphenols distributed in the various plants, which possess intensive biological activities. In this study, the interaction mechanisms between four flavonoids containing one glucose unit with similar molecular weight isolated from the Tibetan medicinal herb Pyrethrum tatsienense, namely, apigenin-7-O-ß-D-glucoside(1), luteolin-7-O-ß-D-glucoside(2), quercetin-7-O-ß-D-glucoside(3), quercetin-3-O-ß-D-glycoside(4), and human serum albumin(HSA), were investigated by fluorescence, UV-vis absorbance, circular dichroism, and molecular modeling. The effects of biological metal ions Mg2+, Zn2+, and Cu2+ on the binding affinity between flavonoids and HSA were further examined. Structure-activity relationships of four flavonoids binding to HSA were discussed in depth and some meaningful conclusions have been drawn by the experiment data and theoretical simulation. In addition, an interesting phenomenon was observed that the microenvironment of the binding site I in HSA has hardly changed in the presence of 4 differentiating from the other three flavonoids on the basis of conformation investigations.