Longitudinal analysis of tear cathepsin S activity levels in male non-obese diabetic mice suggests its potential as an early stage biomarker of Sjögren’s Syndrome

Context: Cathepsin S (CTSS) activity is elevated in Sjögren’s Syndrome (SS) patient tears.

Objective: To evaluate longitudinal expression of tear and tissue CTSS activity relative to other disease indicators in Non-Obese Diabetic (NOD) mice.

Methods: CTSS activity was measured in tears and lacrimal glands (LG) from male 1–6?month (M) NOD and 1 and 6?M BALB/c mice. Lymphocytic infiltration was quantified by histopathology, while disease-related proteins (Rab3D, CTSS, collagen 1) were quantified using q-PCR and immunofluorescence.

Results: In NOD LG, lymphocytic infiltration was noted by 2?M and established by 3?M (p?<?0.01). IFN-?, TNF-α, and MHC II expression were increased by 2?M (p?<?0.01). Tear CTSS activity was significantly elevated at 2?M (p?<?0.001) to a maximum of 10.1-fold by 6?M (p?<?0.001). CTSS activity in LG lysates was significantly elevated by 2?M (p?<?0.001) to a maximum of 14-fold by 3?M (p?<?0.001). CTSS and Rab3D immunofluorescence were significantly increased and decreased maximally in LG acini by 3?M and 2?M, respectively. Comparable changes were not detected between 1 and 6?M BALB/c mouse LG, although Collagen 1 was decreased by 6?M in LG of both strains.

Conclusion: Tear CTSS activity is elevated with other early disease indicators, suggesting potential as an early stage biomarker for SS.     

Understanding the binding of quinoline amines with human serum albumin by spectroscopic and induced fit docking methods

Seven new quinoline-based bioorganic compounds were prepared by solvent-free synthesis and characterized using spectral techniques. The binding of these compounds with human serum albumin (HSA) was investigated by multi-spectroscopic methods. The quenching of Trp fluorescence upon addition of these compounds to HSA confirmed their significant binding. The quenching analysis at three different temperatures revealed that the complex formation is static and the reaction is entropy driven, spontaneous, and exothermic. Hydrogen bonds and van der Waals forces mainly contributed in the interactions as confirmed by the negative ΔH and ΔS values as well as molecular docking. The results from the circular dichroism (CD) spectroscopy indicated the minimal conformational changes of the protein upon binding with these quinoline compounds. The specific binding site and mode of interactions with HSA were also modeled using induced fit molecular docking procedure and their binding site was found to be in the interface of domains II and III, which is similar to the binding of the drug iodipamide with serum albumin.

Communicated by Ramaswamy H. Sarma     

Characterizing the interaction between pyrogallol and human serum albumin by spectroscopic and molecular docking methods

In the present study, the interaction of Pyrogallol (PG) with human serum albumin (HSA) was investigated by UV, fluorescence, Circular dichroism (CD), and molecular docking methods. The results of fluorescence experiments showed that the quenching of intrinsic fluorescence of HSA by PG was due to a static quenching. The calculated binding constants (K) for PG-HSA at different temperatures were in the order of 10⁴?M ^?1, and the corresponding numbers of binding sites, n were approximately equal to unity. The thermodynamic parameters, ΔH and ΔS were calculated to be negative, which indicated that the interaction of PG with HSA was driven mainly by van der Waals forces and hydrogen bonds. The negative value was obtained for ΔG showed that the reaction was spontaneous. In addition, the effect of PG on the secondary structure of HSA was analyzed by performing UV–vis, synchronous fluorescence, and CD experiments. The results indicated that PG induced conformational changes in the structure of HSA. According to Förster no-radiation energy transfer theory, the binding distance of HSA to PG was calculated to be 1.93?nm. The results of molecular docking calculations clarified the binding mode and the binding sites which were in good agreement with the results of experiments.

Communicated by Ramaswamy H. Sarma     

Release kinetics of high-sensitivity cardiac troponins I and T and troponin T upstream open reading frame peptide (TnTuORF) in clinically induced acute myocardial infarction

Context: Troponin T upstream open reading frame peptide (TnTuORF) may be useful as a novel biomarker in acute cardiac syndromes.

Objective: The study examined the early release kinetics of TnTuORF.

Materials and methods: We analyzed the time course of the release of cardiac troponins I and T and TnTuORF in patients (n?=?31) with hypertrophic obstructive cardiomyopathy undergoing transcoronary ablation of septal hypertrophy (TASH).

Results: Fifteen minutes after TASH, the levels of both troponins increased significantly (cTnT median: 18?ng/L versus 27?ng/L; cTnI median: 15?ng/L versus 25?ng/L). TnTuORF showed no variation.

Discussion: We observed a significantly greater increase in cTnI compared with cTnT.

Conclusion: Our results demonstrate that troponin assays allow early detection of myocardial injury, whereas TnTuORF levels remain unchanged in this setting.     

Insights about resveratrol analogs against trypanothione reductase of Leishmania braziliensis: Molecular modeling,computational docking and in vitro antileishmanial studies

In this work, we combined molecular modeling, computational docking and in vitro analysis to explore the antileishmanial effect of some resveratrol analogs (ResAn), focusing on their pro-oxidant effect. The molecular target was the trypanothione reductase of Leishmania braziliensis (LbTryR), an essential component of the antioxidant defenses in trypanosomatid parasites. Three-dimensional structures of LbTryR were modeled and molecular docking studies of ResAn1-5 compounds showed the following affinity: ResAn1?>?ResAn2?>?ResAn4?>?ResAn5?>?ResAn3. Positive correlation was observed between these compounds’ affinity to the LbTryR and the IC₅₀ values against Leishmania sp (ResAn1?<?ResAn2?<?ResAn4), which allows for TryR being considered an important target for them. As the compound ResAn1 showed the best antileishmanial activity, and docking studies showed its high affinity for NADP binding site (NS) of TryR, plus having been able to induce ROS production in L. braziliensis promastigotes treated, ResAn1 probably occupies NS interfering in the electron transfer processes responsible for the catalytic reaction. The in silico prediction of ADMET properties suggests that ResAn1 may be a promising drug candidate with properties to cross biological membranes and high gastrointestinal absorption, not violating Lipinski’s rules. Ultimately, the antileishmanial effect of ResAn can be associated with a pro-oxidant effect which, in turn, can be exploited as an antimicrobial agent.

Communicated by Ramaswamy H. Sarma     

Effect of (–)-epicatechin-3-gallate and (–)-epigallocatechin-3-gallate on the binding of tegafur to human serum albumin as determined by spectroscopy,isothermal titration calorimetry,and molecular docking

Green tea has attracted great interest as a cancer prevention agent. Interactions of tea polyphenols with serum albumin may influence the efficacy of drugs. The interactions of (–)-epigallocatechin-3-gallate (EGCG), (–)-epicatechin-3-gallate (ECG), and tegafur (TF) alone or in combination with human serum albumin (HSA) at pH 7.4 and different temperatures were investigated by spectroscopic methods, isothermal titration calorimetry (ITC), and molecular docking. The binding affinities to HSA were ranked in the order of EGCG?>?ECG?>?TF, and the interactions were spontaneous and exothermic. Ternary system studies showed that the presence of one component hindered the binding of another component to HSA. The secondary structures of HSA were slightly altered in the presence of the ligands. Site marking experiments and molecular docking showed that EGCG and ECG mainly bound to subdomain IIA and ΙΙΙA while TF bound to subdomain ΙΙA and ΙB. Results indicated that the existence of ECG and EGCG would influence the binding of TF to HSA and can increase the free concentration of TF. Obtained results would provide beneficial information about possible interference upon simultaneous co-administration of the tea components and drugs.

Communicated by Ramaswamy H. Sarma     

Insights into the interaction of ulipristal acetate and human serum albumin using multi-spectroscopic methods,molecular docking,and dynamic simulation

Interaction between ulipristal acetate (UPA) and human serum albumin (HSA) was investigated in simulated physiological environment using multi-spectroscopic and computational methods. Fluorescence experiments showed that the quenching mechanism was static quenching, which was confirmed by the time-resolved fluorescence. Binding constants (K_a) were found to be 1?×?10⁵ L mol^?1, and fluorescence data showed one binding site. Thermodynamic constants suggested the binding process was mainly controlled by electrostatic interactions. Results from the competition experiments indicated that UPA bound to site I of HSA. Fourier transform infrared spectra, circular dichroism spectra, synchronous fluorescence spectra, and 3D fluorescence indicated that UPA can induce conformation change in the HSA. The content of α-helix and β-sheet increased, while β-turn decreased. Hydrophobicity around the tryptophan residues declined, whereas its polarity increased. Molecular docking results were consistent with the experimental results. Results suggested that UPA located at the hydrophobic cavity site I of HSA, and hydrophobic force played the key role in the binding process. Moreover, molecular dynamics simulation was performed to determine the stability of free HSA and HSA-UPA system. Results indicated that UPA can stabilize HSA to a certain degree and enhance the flexibility of residues around site I.

Communicated by Ramaswamy H. Sarma     

Interaction and photo–induced cleavage studies of meropenem drug with human serum albumin using spectroscopic and molecular docking investigations

The interaction between Meropenem drug and human serum albumin (HSA) has been studied under physiological condition in Tris–HCl buffer solution at pH 7.4 by various spectroscopic (UV spectra, fluorescence spectra, CD spectra), Photo–induced HSA cleavage, and molecular docking techniques. The results of fluorescence titration revealed that the Meropenem strongly quench the intrinsic fluorescence of HSA through a static quenching procedure. Binding constants (K_b) and the number of binding sites (n ? 1) were calculated using modified Stern–Volmer equations. The thermodynamic parameters ΔG, ΔH and ΔS at different temperatures were calculated which revealed that the electrostatic and hydrogen bonding interactions play a major role in HSA–Meropenem association. The distance r between donor (HSA) and acceptor (Meropenem) was obtained according to fluorescence resonance energy transfer (FRET) and the alterations of HSA secondary structure induced by Meropenem were confirmed by FT–IR and CD measurements. The molecular docking technique was utilized to ascertain the mechanism and mode of action towards the molecular target HSA indicating that Meropenem was located within the subdomain IIA of protein by electrostatic interactions and hydrogen bonds, consistent with the corresponding experimental results. Additionally, Meropenem shows efficient photo–induced HSA cleavage. Our results may provide valuable information to understand the mechanistic pathway of drug delivery and to pharmacological behavior of drug.

• Research Highlights

• The interaction of Meropenem with HSA was studied by spectroscopic, photo-induced cleavage and molecular docking techniques.

• The secondary structure of protein has been changed upon the interaction with Meropenem.

• Subdomain IIA of the HSA is found to be the main binding site for Meropenem.

Communicated by Ramaswamy H. Sarma     

Associations of rs1883832 and rs4810485 polymorphisms of CD40 gene with myocardial infarction in the Tunisian population

Context: Cluster of differentiation 40 (CD40), and its ligand CD40L, are major co-stimulatory molecules whose interactions are important in both cellular and humoral immunity, and has been suggested to play a role in the pathogenesis of acute coronary syndrome.

Objective: The aim of this study was to examine the association of CD40 polymorphisms (-1?C>T (rs1883832) and 945G>T (rs4810485)) and myocardial infarction (MI), and to test the association of CD40 gene haplotypes with MI in Tunisians.

Materials and methods: Three hundred and fifty MI patients and 301 apparently healthy controls were included in the study. The polymorphisms of CD40 were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results: There were significant differences in the genotype and allele frequencies of CD40 gene -1?C>T (rs1883832) polymorphism between cases and controls. Stratifying according to gender, the association between the TT genotype and MI was statistically significant in males, only. Haplotype analysis revealed that the C-T and T-G haplotypes were associated with an increased risk of MI (p?=?0.012 and p?<?0.001, respectively).

Conclusions: Our work showed a significant association between the -1?C>T (rs1883832) polymorphism of the CD40 gene and MI in the Tunisians.     

Nanostructured lipid carriers as semisolid topical delivery formulations for diflucortolone valerate

Context: Topical treatment of skin disease needs to be strategic to ensure high drug concentration in the skin with minimum systemic absorption.

Objective: The aim of this study was to produce semisolid nanostructured lipid carrier (NLC) formulations, for topical delivery of the corticosteroid drug, diflucortolone valerate (DFV), with minimum systemic absorption.

Method: NLC formulations were developed using a high shear homogenization combined with sonication, using Precirol® ATO5 or Tristearin® as the solid lipid, Capryol? or isopropyl myristate as the liquid lipid and Poloxamer® 407 as surfactant. The present study addresses the influence of different formulations composition as solid lipid, liquid lipid types and concentrations on the physicochemical properties and drug release profile from NLCs.

Results and discussion: DFV-loaded NLC formulations possessed average particle size ranging from 160.40?nm to 743.7?nm with narrow polydispersity index. The encapsulation efficiency was improved by adding the lipid-based surfactants (Labrasol® and Labrafil® M1944CS) to reach 68%. The drug release from the investigated NLC formulations showed a prolonged release up to 12?h. The dermatopharmacokinetic study revealed an improvement in drug deposition in the skin with the optimized DFV-loaded NLC formulation, in contrast to a commercial formulation.

Conclusion: NLC provides a promising nanocarrier system that work as reservoir for targeting topical delivery of DFV.     

Study on the interaction of fisetholz with BSA/HSA by multi-spectroscopic,cyclic voltammetric,and molecular docking technique

The interaction of fisetholz with bovine serum albumin (BSA) and human serum albumin (HSA) was investigated by multi-spectroscopic, cyclic voltammetric, and molecular docking technique. The results revealed that there was a static quenching of BSA/HSA induced by fisetholz. The binding constants (K_a) and binding sites (n) were calculated at different temperatures (293, 303, and 311?K). The enthalpy change (ΔH) were calculated to be –17.20?kJ mol^?1 (BSA) and –18.28?kJ mol^?1 (HSA) and the entropy change (ΔS) were calculated to be 35.41?J mol^?1 (BSA) and 24.02?J mol^?1 (HSA), respectively, which indicated that the interaction between fisetholz and BSA/HSA was mainly by electrostatic attraction. Based on displacement experiments using site probes, indomethacin and ibuprofen, the binding site of fisetholz to BSA/HSA was identified as sub-domain IIIA, which was further confirmed by molecular docking method. There was little effect of K⁺, Ca²⁺, Cu²⁺, Zn²⁺, and Fe³⁺ on fisetholz-BSA or fisetholz-HSA complex. The spectra of synchronous fluorescence, circular dichroism (CD) and Fourier transform infrared (FT-IR) all showed that fisetholz binding to BSA/HSA leads to secondary structures change of the two serum albumins. According to the Förster non-radiation energy transfer theory, the binding distance between fisetholz and BSA/HSA was 2.94/4.68?nm. The cyclic voltammetry as a supporting tool also indicated that fisetholz interacted with protein.

Communicated by Ramaswamy H. Sarma     

Structure based virtual screening, 3D-QSAR,molecular dynamics and ADMET studies for selection of natural inhibitors against structural and non-structural targets of Chikungunya

The transmission of mosquito-borne Chikungunya virus (CHIKV) has large epidemics worldwide. Till date, there are neither anti-viral drugs nor vaccines available for the treatment of Chikungunya. Accumulated evidences suggest that some natural compounds i.e., Epigallocatechin gallate, Harringtonine, Apigenin, Chrysin, Silybin, etc. have the capability to inhibit CHIKV replication in vitro. Natural compounds are known to possess less or no side effects. Therefore, natural compound in its purified or crude extracts form could be the preeminent and safe mode of therapies for Chikungunya. Wet lab screening and identification of natural compounds against Chikungunya targets is a time consuming and expensive exercise. In the present study, we used in silico techniques like receptor-ligand docking, Molecular dynamic (MD), Three Dimensional Quantitative Structure Activity Relation (3D-QSAR) and ADME properties to screen out potential compounds. Aim of the study is to identify potential lead/s from natural sources using in silico techniques that can be developed as a drug like molecule against Chikungunya infection and replication. Three softwares were used for molecular docking studies. Potential ligands selected by docking studies were subsequently subjected 3D-QSAR studies to predict biological activity. Based on docking scores and pIC₅₀ value, potential anti-Chikungunya compounds were identified. Best docked receptor-ligands were also subjected to MD for more accurate estimation. Lipinski’s rule and ADME studies of the identified compounds were also studied to assess their drug likeness properties. Results of in silico findings, led to identification of few best fit compounds of natural origin against targets of Chikungunya virus which may lead to discovery of new drugs for Chikungunya.

Communicated by Ramaswamy H. Sarma     

Molecular dynamics and combined docking studies for the identification of Zaire ebola virus inhibitors

Ebola virus (EBOV) is a lethal human pathogen with a risk of global spread of its zoonotic infections, and Ebolavirus Zaire specifically has the highest fatality rate amongst other species. There is a need for continuous effort towards having therapies, as a single licensed treatment to neutralize the EBOV is yet to come into reality. This present study virtually screened the MCULE database containing almost 36 million compounds against the structure of a Zaire Ebola viral protein (VP) 35 and a consensus scoring of both MCULE and CLCDDW docking programs remarked five compounds as potential hits. These compounds, with binding energies ranging from –7.9 to –8.9?kcal/mol, were assessed for predictions of their physicochemical and bioactivity properties, as well as absorption, distribution, metabolism, excretion, and toxicity (ADMET) criteria. The results of the 50?ns molecular dynamics simulations showed the presence of dynamic stability between ligand and protein complexes, and the structures remained significantly unchanged at the ligand-binding site throughout the simulation period. Both docking analysis and molecular dynamics simulation studies suggested strong binding affinity towards the receptor cavity and these selected compounds as potential inhibitors against the Zaire Ebola VP 35. With respect to inhibition constant values, bioavailability radar and other physicochemical properties, compound A (MCULE-1018045960-0-1) appeared to be the most promising hit compound. However, the ligand efficiency and ligand efficiency scale need improvement during optimization, and also validation via in vitro and in vivo studies are necessary to finally make a lead compound in treating Ebola virus diseases.

Communicated by Ramaswamy H. Sarma     

Trypsin inhibition by Ligupurpuroside B as studied using spectroscopic,CD, and molecular docking techniques

It is well known that Ligupurpuroside B is a water-soluble polyphenolic compound and used to brew bitter tea with antioxidant activities. It acted as a stimulant to the central nervous system and a diuretic (increase the excretion of urine), was used to treat painful throat and high blood pressure, and also exerted weight-loss function. In this regard, a detailed investigation on the mechanism of interaction between Ligupurpuroside B and trypsin could be of great interest to know the pharmacokinetic behavior of Ligupurpuroside B and for the design of new analogues with effective pharmacological properties. Ligupurpuroside B successfully quenched the intrinsic fluorescence of trypsin via static quenching mechanism. The binding constants (K_a) at three temperatures (288, 298, and 308 K) were 1.7841?×?10⁴, 1.6251?×?10⁴ and 1.5483?×?10⁴ L mol^?1, respectively. Binding constants revealed the stronger binding interaction between Ligupurpuroside B and trypsin. The number of binding sites approximated to one, indicating a single class of binding for Ligupurpuroside B in trypsin. The enzyme activity result suggested that Ligupurpuroside B can inhibit trypsin activity. Thermodynamic results revealed that both hydrogen bonds and hydrophobic interactions play main roles in stabilization of Ligupurpuroside B-trypsin complex. Circular dichroism (CD) results showed that the conformation of trypsin changed after bound to ligupurpuroside B. Molecular docking indicated that Ligupurpuroside B can enter the hydrophobic cavity of trypsin and was located near Trp215 and Tyr228 of trypsin.

Communicated by Ramaswamy H. Sarma     

The GALA study: relationship between galectin-3 serum levels and short- and long-term outcomes of patients with acute heart failure

Objective: We tested the hypothesis that early measurement of galectin-3 at the emergency department (ED) during an episode of acute heart failure (AHF) allows predicting short- and long-term outcomes.

Methods: We performed an exploratory study including 115 patients consecutively diagnosed with AHF in a single ED. Clinical and analytical variables were recorded. The primary endpoint was 30-day all-cause mortality, and secondary endpoints were 30-day composite outcome (death, rehospitalization or ED reconsultation, whichever first) and 1-year mortality.

Results: Seven patients (6.1%) died within 30?days and 43 (37.4%) within 1?year. The 30-day composite endpoint was observed in 21.1% of patients. Galectin-3 was correlated with NT-proBNP and the glomerular filtration rate but not with age and s-cTnI. Measured at time of ED arrival, galectin-3 showed good discriminatory capacity for 30-day mortality (AUC ROC: 0.732; 95% CI 0.512–0.953; p?=?0.041) but not for 1-year mortality (0.521; 0.408–0.633; p?=?0.722). Patients with galectin-3 concentrations?>42?μg/L had an OR?=?7.67(95%CI?=?1.57-37.53; p?=?0.012) for 30-day mortality. Conversely, NT-proBNP only showed predictive capacity for 1-year mortality (0.642; 0.537–0.748; p?=?0.014). Patients with NT-proBNP concentrations?>5400?ng/L had an OR?=?4.34 (95%CI?=?1.93-9.77; p?<?0.001) for 1-year mortality. These increased short- (galectin-3) and long-term (NT-proBNP) risks remained significant after adjustment for age or renal function. s-cTnI failed in both short- and long term death prediction. No biomarker predicted the short-term composite endpoint.

Conclusion: These results suggest that galectin-3 could help to monitor the risk of short-term mortality in unselected patients with AHF attended in the ED.     

Plant sex and phenological stage affect interactions with rhizosphere nematode communities

Background: In dioecious plants, females and males associate differently with mycorrhizal fungi, but interactions with other rhizosphere organisms are less well studied.

Aims: We investigated the effect of plant sex on rhizosphere nematode communities associated with Corema album, a dioecious shrub occurring in coastal habitats.

Methods: Rhizosphere samples were collected from males and females in three populations (150 plants), during fruiting and flowering. Nematode communities were characterised and compared between plant sexes through statistical analyses of the abundance of trophic groups, plant parasitic nematode (PPN) genera and ecological indices.

Results: Free-living nematodes showed no statistically significant differences owing to plant sex. Conversely, PPN community composition was significantly different between plant sexes during fruiting but not flowering, suggesting that physiological requirements over the annual phenological cycle of the plant influence ecological interactions with the rhizosphere.

Of the 13 PPN genera identified, the ectoparasitic Criconema and Hemicriconemellawere more abundant in the rhizosphere of males during fruiting, whereas the endoparasitic Meloidogyne associated more frequently with females, suggesting that plant host suitability is related to PPN feeding strategy.

Conclusions: It appears that interactions of individuals of different sexes of C. album with the rhizosphere nematode community vary with phenological stage, especially for PPN.     

Design of novel quinoline-aminopiperidine derivatives as Mycobacterium tuberculosis (MTB) GyrB inhibitors: an in silico study

Tuberculosis (TB) is an infectious disease that causes a number of deaths, and the development of new, safer and more adequate TB inhibitors/drugs has become a necessity as well as a great challenge. Mycobacterial DNA gyrase B subunit has been identified to be one of the potentially underexploited drug targets in the field of anti-tubercular drug discovery. To design the novel and potent Mycobacterium tuberculosis (MTB) inhibitors, we performed molecular modeling studies that combined the 3D-QSAR, molecular docking, molecular dynamics (MD) simulations, and binding free energy calculations. Forty eight quinoline-aminopiperidine inhibitors which act on DNA gyrase B subunit were used for constructing 3D-QSAR models. The results showed that the best CoMFA model had the high performance with q²?=?0.643, r²?=?0.947, while the best CoMSIA model yielded q²?=?0.536, r²?=?0.948. The contour map was in good agreement with the docking and MD simulations which strongly demonstrated that the molecular modeling was reliable. Based on this information, several potential compounds were designed and their inhibitory activities were also verified by the accomplished models and ADME/T predictions. We hope that our research could bring new ideas to facilitate the development of novel inhibitors with higher inhibitory activity for TB.

Communicated by Ramaswamy H. Sarma     

A new nitrobenzoxadiazole-based GSTP1-1 inhibitor with a previously unheard of mechanism of action and high stability

Context: The nitrobezoxadiazole derivative NBDHEX is a potent inhibitor of glutathione transferase P1-1 (GSTP1-1) endowed with outstanding anticancer activity in different tumor models.

Objective: To characterize by in vitro biochemical and in silico studies the NBDHEX analogues named MC2752 and MC2753.

Materials and methods: Synthesis of MC2752 and MC2753, biochemical assays and in silico docking and normal-mode analyses.

Results: The presence of a hydrophobic moiety in the side chain of MC2753 confers unique features to this molecule. Unlike its parent drug NBDHEX, MC2753 does not require GSH to trigger the dissociation of the complex between GSTP1-1 and TRAF2, and displays high stability towards the nucleophilic attack of the tripeptide under physiological conditions.

Discussion and conclusion: MC2753 may represent a lead compound for the development of novel GSTP1-1 inhibitors not affected in their anticancer action by fluctuations of cellular GSH levels, and characterized by an increased half-life in vivo.     

Habitat associations of young Black Grouse Tetrao tetrix broods

Capsule: In the Scottish Highlands, Black Grouse Tetrao tetrix females with young broods selected areas rich in wet flushes, grasses and Sphagnum mosses.

Aims: To identify associations between young Black Grouse broods and habitat characteristics.

Methods: We located brood-rearing Black Grouse females in four areas of moorland-forest mosaic in the Scottish Highlands. Each brood was paired with a random reference location 100?m away. We recorded cover of different habitats and fine-scale vegetation and structure within squares of 1 and 0.25?ha, respectively. Associations between brood occurrence and habitat and vegetation variables were examined at the two scales.

Results: Black Grouse broods were positively associated with wet flushes (1?ha), and with Heather Calluna vulgaris, sedges Carex spp., grasses, Sphagnum mosses and taller vegetation with intermediate levels of height variability (0.25?ha).

Conclusions: This study highlights the importance of wet habitats for young Black Grouse chicks. In addition, relatively tall field-layer vegetation comprising Heather, sedges, grasses over a layer of Sphagnum mosses attracted brood-rearing Black Grouse females. Many management practices associated with peatland restoration, including drain-blocking, Sphagnum re-establishment and the avoidance of burning on deep peat soils, are therefore consistent with favourable habitat management for Black Grouse.     

Effect of liposome-treated red blood cells in an anemic rat model

Context: Liposomes have been shown to improve human red blood cell (RBC) in vitro quality by minimizing membrane damage occurring during 42-d hypothermic storage. Small animal models are necessary to evaluate novel blood products and guide future clinical studies.

Objectives: The aim of this study was to assess the effect of liposome treatments on rat RBC hypothermic storage lesion (HSL) and to examine in vivo outcomes of transfusing liposome treated RBCs in a rat model.

Materials and methods: Unilamellar liposomes were synthesized which contained saturated (DPPC:CHOL, 7:3?mol%), unsaturated (DOPC:CHOL, 7:3?mol%), saturated charged (DPPC:CHOL:PS, 6:3:1?mol%), and unsaturated charged (DOPC:CHOL:PS, 6:3:1?mol%) phospholipids. After liposome treatment, rat RBC quality was assessed by percent hemolysis, deformability, aggregation, hematological indices, microvesiculation, and cholesterol/phospholipid concentrations. An anemic rat model of myocardial ischemia and reperfusion (I/R) was used to evaluate the outcomes of transfusing liposome-treated RBCs.

Results: All four liposome treatments resulted in significant decreases in hemolysis, with the most prominent effect seen with DOPC-liposomes (DOPC: 1.6?±?0.1% versus control: 3.1?±?0.2%, p?=?0.015). RBCs treated with uncharged liposomes had lower hemolysis compared with charged liposomes (3.4?±?0.2% versus 3.9?±?0.4%, p?=?0.010). The in vivo study showed no significant difference in the hemoglobin levels and infarct size (53.3?±?13.1% versus 45.3?±?8.4%, p?=?0.223) between liposome and control groups.

Discussion and conclusion: Liposome treatment improved in vitro quality of stored rat RBCs. However, the changes observed in vitro were not sufficient to improve the in vivo outcomes of myocardial I/R in anemic rats transfused with liposome-treated RBCs.