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Heparin has been documented to reduce myocardial injury caused by ischemia/reperfusion (I/R), but its clinical application is limited due to its strong intrinsic anticoagulant property. Some desulfated derivatives of heparin display low anticoagulant activity and may have potential value as therapeutic agents for myocardial I/R injury. In this study, we observed that 6-O-desulfated heparin, a desulfated derivative of heparin, shortened the activated partial thromboplastin time and exhibited lower anticoagulant activity compared with heparin or 2-O-desulfated heparin (another desulfated derivative of heparin). Then, we explored whether 6-O-desulfated heparin could protect against myocardial I/R injury, and elucidated its possible mechanisms. Administration of 6-O-desulfated heparin significantly reduced creatine kinase activity, myocardial infarct size and cell apoptosis in mice subjected to 30 min of myocardial ischemia following 2 h of reperfusion, accompanied by a reverse in miR-199a-5p elevation, klotho downregulation and reactive oxygen species (ROS) accumulation. In cultured H9c2 cells, the mechanism of 6-O-desulfated heparin against myocardial I/R injury was further explored. Consistent with the results in vivo, 6-O-desulfated heparin significantly ameliorated hypoxia/reoxygenation-induced injury, upregulated klotho and decreased miR-199a-5p levels and ROS accumulation, and these effects were reversed by miR-199a-5p mimics. In conclusion, these results suggested that 6-O-desulfated heparin with lower anticoagulant activity attenuated myocardial I/R injury through miR-199a-5p/klotho and ROS signaling. Our study may also indicate that 6-O-desulfated heparin, as an excellent heparin derivative, is a potential therapeutic agent for myocardial I/R injury.

Objective K+-Cl- cotransporter-2 (KCC2), which primarily extrudes chloride in mature neurons, triggers hemiplegia limb spasticity after ischemic stroke by affecting neuronal excitability. Our previous study revealed that the Chinese herb Baishaoluoshi Decoction decreases hemiplegia limb spasticity in poststroke spasticity (PSS) patients. This study aimed at elucidating on the effects of Baishaoluoshi Decoction on the BDNF/TrKB-KCC2 pathway in PSS rat models. Methods Middle cerebral artery occlusion (MCAO) was adopted for the establishment of PSS rat models. Muscle tension was evaluated by Modified Ashworth Scale. Nissl staining and transmission electron microscopy were used to measure the protective effects of Baishaoluoshi Decoction on ischemic injury-induced neuronal damage due to MCAO. Expression levels of BDNF, TrKB, and KCC2 in brain tissues around the infarct and brainstem were detected by immunohistochemical staining. Results It was found that Baishaoluoshi Decoction suppressed hemiplegia limb spasticity and alleviated the damage in neurons and synapses in PSS rat models. Importantly, the expression of BDNF, TrKB, and KCC2 in brain tissues around the infarct and brainstem were significantly upregulated after treatment with low-dose and high-dose Baishaoluoshi Decoction. Conclusion Suppression of spasticity by Baishaoluoshi Decoction in PSS rat models may be correlated with upregulated BDNF/TrKB-KCC2 pathway, which may be a complementary therapeutic strategy for PSS.

Energy transfer was explored in a series of poly(phenylene ethynylene) (PPE) polymers with increasing lengths that were end-capped with thiophene-benzothiadiazole (TBT) groups to form fully conjuga...

BackgroundStroke is the first leading cause of mortality and disability worldwide, and post-stroke spasticity (PSS) is the common complication of stroke. Sangdantongluo Granule, a modern patent Traditional Chinese medicine (TCM), is widely used in clinical practice to treat PSS. Whereas, there is limited evidence of effectiveness for Sangdantongluo Granule to treat PSS. This study will evaluate the clinical efficacy and safety of Sangdantongluo granule in the treatment of PSS. MethodsThis multicenter, randomized, double-blind and placebo-controlled study will recruit 132 participants in China who develops PSS 15 days to 90 days after stroke. Participants will be randomly assigned in an equal ratio to receive either Sangdantongluo granule or placebo for 2 months twice a day orally. The primary measure is the Modified Ashworth Scale (MAS), Secondary outcome measures include Compopsite Spasticity Scale (CSS), Simplified Fugl-Meyer Motor Scale (S-FM), National Institute of Health stroke scale (NIHSS), Modified Rankin Scale (mRS), Modified Barther Index (MBI), and Surface electromyography. Adverse events will be supervised throughout the trial. DiscussionThe results of this study will present whether Sangdantongluo granule is clinical effective and safe for managing PSS.Trial registrationClinicalTrials.gov ChiCTR2100044544. Registered on 23 March 2021.

Diabetes mellitus is one of the top four leading causes of death among noncommunicable diseases worldwide, according to the World Hibiscus sabdariffa 2019. Roselle (Hibiscus sabdariffa L.), a traditional herbal medicine, has shown significant clinical anti-hyperglycemic efficacy. However, the mechanism of the treatment is not yet clear. We found that Roselle has a certain protective effect on vascular endothelial cells through this study. This study was based on network pharmacology and experimental validation. The present study made a comprehensive analysis by combining active ingredient screening, target prediction and signaling pathway analysis to elucidate the active ingredients and possible molecular mechanism of roselle for the first time, which provided theoretical and experimental basis for the development and application of roselle as an antidiabetic drug.

Control of photoinduced electron transfer through selective excitation of a π-conjugated diblock oligomeric system featuring tetrathiophene (T4) and tetra(phenylene ethynylene) (PE4) donor blocks c...

The trimeric perfluoro-o-phenylene mercury compound Hg3 and poly(2-methoxy,5-(2′-ethylhexyloxy)-1,4-phenylenevinylene (MEH-PPV) interact strongly in solution and the solid state. The interaction is attributed to electron donor–acceptor complex formation, where MEH-PPV is the donor, and the Lewis acid Hg3 is the acceptor. The study reported herein explores the effects of the donor–acceptor complex formation on the properties of MEH-PPV in solution and in the solid state. Addition of Hg3 to MEH-PPV solution or films leads to a distinct color change, and the change in the visible absorption spectrum and fluorescence of MEH-PPV is consistent with the formation of polymer aggregates. In the solid state, Hg3 induced aggregation is suggested to lead to formation of crystalline domains of the conjugated polymer. Transmission electron microscopy and grazing incidence X-ray scattering results support the hypothesis that the complex formation with Hg3 induces aggregation of the polymer. Transient absorption spectros...

A polystyrene-based chromophore-catalyst assembly (poly-2) has been synthesized and assembled at a mesoporous metal oxide photoanode. The assembly contains water oxidation catalyst centers based on [Ru(trpy) (phenq)]2+ (Ru-Cat) and [Ru(bpy)3]2+ derivatives (Ru-C) as chromophores (trpy= 2,2′;6,2″- terpyridine, phenq = 2-(quinol-8′-yl)-1,10-phenanthroline and bpy = 2,2′-bipyridine). The photophysical and electrochemical properties of the polychromophore-oxidation catalyst assembly were investigated in solution and at the surface of mesoporous metal oxide films. The layer-by-layer (LbL) method was utilized to construct multilayer films with cationic poly-2 and anionic poly(acrylic acid) (PAA) for light-driven photochemical oxidations. Photocurrent measurements of (PAA/poly-2)10 LbL films on mesoporous TiO2 demonstrate light-driven oxidation of phenol and benzyl alcohol in aqueous solution. Interestingly, illumination of (PAA/poly-2)5 LbL films on a fluorine doped SnO2/TiO2 core/shell photoanode in aqueous so...

Background Chinese medicine Sangbaipi decoction is extensively applied to the therapy of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in China. However, owing to the low quality, small sample size, and methodological heterogeneity of these studies, this conclusion is not convincing. Consequently, it is necessary to systematically evaluate the clinical efficacy and safety of Sangbaipi Decoction in the treatment of AECOPD patients, and provide high-quality evidence for its clinical application. Methods We will follow the preferred reporting items for systematic review and meta-analysis (PRISMA) for reporting the results of the review in this study. We will utilize the Review Manage software V5.3.0 (The Nordic Cochrane Center, The Cochrane Collaboration, 2014, Copenhagen, Denmark) to assess the risk of bias and visualize the results. We will use Stata software (version 15.0, StataCorp, College Station, TX) to perform the meta-analysis. Ethics and dissemination This study is a systematic review and meta-analysis protocol of Sangbaipi decoction on AECOPD, participants were not recruited and data were not collected from participants, so ethical ratification is not required. Results This study will provide high-quality synthesis of the effectiveness and safety of Sangbaipi decoction for AECOPD. Upon completion, the results will be submitted to a peer-reviewed journal. Conclusion The efficacy and safety assessment of Sangbaipi decoction for AECOPD will be supported by this protocol. Registration number PROSPERO CRD 42019138405.

A series of polystyrene-based light harvesting polymers featuring pendant polypyridyl ruthenium complexes has been synthesized. The polymer backbones were prepared by nitroxide-mediated radical polymerization with a variable average molecular weight (Mn) ranging from ∼5500 to ∼24 000 g mol−1. Pendant Ru(II) polypyridyl complexes were grafted to the polymer backbone by azide–alkyne click chemistry to afford chromophore loaded polymers. The resulting polystyrene-based polychromophores with pendant Ru(II) polypyridyl complexes (PS-Ru) were characterized by nuclear magnetic resonance and infrared spectroscopy, confirming the high efficiency of the click grafting. The photophysical and electrochemical properties of the series of PS-Ru polymers were characterized in solution and investigated as a function of polymer chain length and solvent. The electrochemical properties of PS-Ru maintained the characteristics of the individual Ru(II) polypyridyl units. Emission quantum yield and lifetime studies reveal that the metal-to-ligand charge transfer (MLCT) excited states are quenched to a variable extent depending on the molecular weight of the polymers, consistent with intramolecular energy transfer and self-quenching in polymers with longer chain lengths. To support the synthetic effort, molecular dynamics simulations of the polypyridyl ruthenium derivatized polystyrenes in different solvents were conducted.

A series of π-conjugated oligomer-acceptor dyads were synthesized that feature oligo(phenylene ethynylene) (OPE) conjugated backbones end-capped with a naphthalene diimide (NDI) acceptor. The OPE segments vary in length from 4 to 8 phenylene ethynene units (PEn-NDI, where n = 4, 6 and 8). Fluorescence and transient absorption spectroscopy reveals that intramolecular OPE → NDI charge transfer dominates the deactivation of excited states of the PEn-NDI oligomers. Both charge separation (CS) and charge recombination (CR) are strongly exothermic (ΔG0CS ∼ −1.1 and ΔG0CR ∼ −2.0 eV), and the driving forces do not vary much across the series because the oxidation and reduction potentials and singlet energies of the OPEs do not vary much with their length. Bimolecular photoinduced charge transfer between model OPEs that do not contain the NDI acceptors with methyl viologen was studied, and the results reveal that the absorption of the cation radical state (OPE+•) remains approximately constant (λ ∼ 575 nm) regardl...

The interactions of two anionic poly(phenylene ethynylene) sulfonate-conjugated polyelectrolytes (mPPESO3– and pPPESO3–) with two alkynylplatinum(II) terpyridine complexes (Pt2+ and Pt3+) were studied. The Pt(II) complexes interact with helical mPPESO3– by intercalation within the polymer helix to form a “guest–host” ensemble. Titration of Pt(II) complexes into an aqueous solution of mPPESO3– gives rise to efficient quenching of the polymer’s fluorescence; meanwhile, triplet metal–metal-to-ligand charge transfer (3MMLCT) state emission from the intercalated Pt(II) complexes appears when the ensembles are excited into the polymer’s absorption band. The 3MMLCT state emission implies that the Pt(II) complexes aggregate or dimerize on the mPPESO3– scaffold. The responses of the mPPESO3– and Pt(II) complex ensembles to various proteins were examined by monitoring the mPPESO3– fluorescence change. Negatively charged proteins recover the mPPESO3– fluorescence more than the positively charged proteins under physi...

This paper describes the photophysical and photoelectrochemical characterization of a light harvesting polychromophore array featuring a polyfluorene backbone with covalently attached Ru(II) polypyridyl complexes (PF-Ru-A), adsorbed on the surface of mesostructured TiO2 (PF-Ru-A//TiO2). The surface adsorbed polymer is characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, providing evidence for the morphology of the surface adsorbed polymer and the mode of binding. Photoexcitation of the Ru(II) complexes bound to the metal oxide surface (proximal) results in electron injection into the conduction band of TiO2, which is then followed by ultrafast hole transfer to the polymer to form oxidized polyfluorene (PF+). More interestingly, chromophores that are not directly bound to the TiO2 interface (distal) that are excited participate in site-to-site energy transfer processes that transport...

Traditional Chinese herbs are regarded as a new and promising source of potential anti-cancer remedies and new chemotherapy adjuvants to enhance the efficacy of chemotherapy and/or to ameliorate its side effects. Extensive investigations have been undertaken both in the experimental and clinical studies over the years to augment the efficacy of chemotherapy. Evodia rutaecarpa is a very popular multi-purpose herb traditionally used in China for the treatment of headaches, abdominal pain, postpartum hemorrhage, dysentery and amenorrhea. The major constituents of Evodia rutaecarpa are evodiamine and rutaecarpine. Growing evidence demonstrates that evodiamine possesses anti-cancer activities both in vitro and in vivo by inhibiting proliferation, invasion and metastasis, inducing apoptosis of a variety of tumor cell lines. This review is aimed to summarize the recent researches on evodiamine focusing on anti-cancer activity and to highlight molecular mechanisms during the past ten years.

A polychromophoric light-harvesting assembly featuring a polystyrene (PS) backbone with ionic carboxylate-functionalized Ru(II) polypyridyl complexes as pendant groups (PS-Ru-A) was synthesized and successfully anchored onto mesoporous structured TiO2 films (TiO2 //PS-Ru-A). Studies of the resulting TiO2 //PS-Ru-A films carried out by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) confirmed that the ionic carboxylated Ru(II) complexes from PS-Ru-A led to the surface immobilization on the TiO2 film. Monochromatic light photocurrent spectroscopy (IPCE) and white light (AM1.5G) current-voltage studies of dye-sensitized solar cells using the TiO2 //PS-Ru-A photoanode give rise to modest photocurrent and white light efficiency (24 % peak IPCE and 0.33 % PCE, respectively). The photostability of surface-bound TiO2 //PS-Ru-A films was tested and compared to a monomeric Ru(II) complex (TiO2 //Ru-A), showing an enhancement of ∼14 % in the photostability of PS-Ru-A. Transient absorption measurements reveal that electron injection from surface-bound pendants occurs on the picosecond time scale, similar to TiO2 //Ru-A, while time-resolved emission measurements reveal delayed electron injection occurring in TiO2 //PS-Ru-A on the nanosecond time scale, underscoring energy transport from unbound to surface-bound complexes. Additionally, charge recombination is delayed in PS-Ru-A, pointing towards intra-assembly hole transport to complexes away from the surface. Molecular dynamics simulations of PS-Ru-A in fluid solution indicate that a majority of the pendant Ru(II) complexes lie within 10-20 A of each other, facilitating efficient energy- and charge transport among the pendant complexes.

Materialized view selection is one of the key techniques for speeding up query answer in a data warehouse environment. To effectively and efficiently deal with this problem, a novel shuffled frog leaping (SFL) algorithm for materialized view selection is proposed in this paper. Experimental results on the TPC-D benchmark data sets show that the proposed algorithm out-performs other well-known algorithms in terms of total maintenance cost and query response time.