An in vitro based investigation into the cytotoxic effects of D-amino acids

In the present study, cytotoxic effects of D-Ala, D-Pro and D-Lys are demonstrated. In an effort to study possible mechanisms of the observed cytotoxicity, catalase activity, H2O2 generation, and apoptotic activity were measured in HeLa and MCF-7 cell lines. Although D-Lys is a poor substrate for DAO and therefore low H2O2 has been detected, it was shown to provoke severe impairment of cellular integrity and survival. Interestingly, a very good substrate for DAO, such as D-Pro, did not substantially reduce cell viability. On the other hand, a moderate substrate for DAO, represented by D-Ala, was shown to moderately trigger toxicity in the tested cell lines. Although a correlation between the in vitro cytotoxicity of D-amino acids and the amount of H2O2 produced was absent, there was a good agreement between the ability of D-amino acids to trigger apoptosis and to provoke toxicity. Our results indicate that the toxicity of D-amino acids does not appear to be solely mediated by H2O2. Therefore, we hypothesize that other possible contributing apoptosis-mediated pathways might cause the observed toxicity

Studies on the interaction between ciprofloxacin hydrochloride and diclofenac sodium

Purpose: To study the interaction between ciprofloxacin hydrochloride (Cipro) and diclofenac sodium (DS) in the presence and absence of metal ions.Methods: Complexes were prepared in the aqueous phase at different molar ratios (r) of Cipro:DS (ranged from 0.2 – 2.0). The complexes were characterized by Fourier transform-infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and high pressure liquid chromatography (HPLC). Their properties, i.e., solubility, dissolution and partition coefficient (log P), were studied along with their permeability across Caco-2 cells. Furthermore, the antimicrobial activity of Cipro and its complexes was determined using standard broth dilution method and expressed as minimum inhibitory concentration (MIC).Results: Cipro formed an ion pair with DS. The product was confirmed to be a combination of the two drugs, DS and Cipro, but in a ratio that is dependent on the added amounts of each component (r = 1:1 or 1:2). The 1:1 product was more lipophilic than the individual components leading to a lower aqueous solubility and a higher octanol/water partition coefficient log P (6.7 vs. 0.77). The presence of DS within the dissolution medium appeared to modify the dissolution of Cipro depending on the concentration. Moreover, ternary complexes involving Cipro, DS and metal ions (iron and/or calcium) exhibited improved antimicrobial effect (MIC, 0.016 μg/ml compared to 0.258 μg/ml for Cipro). Caco-2 cell permeation data indicate that the presence of DS significantly improved the apparent permeability coefficient (Papp) of Cipro (20.6 × 10-6 cm/s) which was three times higher than that of free Cipro (p < 0.05). DS also appeared to counteract the well-known negative effect of metal ions on the bioavailability of Cipro.Conclusion: There is a clinically relevant interaction between DS and Cipro at the absorption level as a result of ion pair formation, which might even counteract the negative effect of metals on the absorption of Cipro. These findings should aid the design of new Cipro ion pairs that provide higher bioavailability than free Cipro.Keywords: Ciprofloxacin, Diclofenac, Interaction, Ion pair, Permeability coefficient, Bioavailability, Absorptio

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Antiproliferative activity of selected medicinal plants of Jordan against a breast adenocarcinoma cell line (MCF7)

76 ethanolic extracts of medicinal herbs from the Jordanian flora, belonging to 67 species and 34 families, were evaluated for their antiproliferative activity on a breast cancer cell line (MCF7). The cells were cultured in RPMI 1640 medium and incubated with the extracts for 72 hours. Sulphorhodamine B (SRB) assay was used to test cytotoxicity. From the tested crude extracts, Inula graveolens, Salvia dominica, Conyza canadiensis and Achillea santolina showed potent antiproliferative activity and the activity resided in the chloroform/ethanolic extracts. The most active plant was I. graveolens with an IC50 of 3.83 μg/ml. Phytochemical screening indicated the presence of flavonoids, terpenoids, and phenolics in all active extracts. These results indicate the possible potential use of medicinal plants from the Jordanian flora as antineoplastic agents

Chromatographic Behaviour and Analytical Method Development for Metformin HCl: Application to Permeation Studies through Caco-2 Cells

Metformin HCl (Mtf) is a polar compound with low bioavailability. Counter ions have been shown to improve the bioavailability of polar ionizable drugs. The goal of this work was to develop an HPLC method that is capable of separating and quantifying Mtf from a group of selected organic anions: diclofenac sodium (DS), citric acid (CA), hydroxyl cinnamic acid (HCA), 8-anilinonaphthalene-1-sulfonic acid (ANS),and trisodium phosphate (TSP). Thus, the effect of the mixture of anions on the transport of Mtf through Caco-2 cells could be studied. During the development of the method, interesting chromatographic behaviors of Mtf were observed using a polar stationary phase (Hypersil® SAS, C1). The developed method was validated and found to be linear in the range 2-100 µg/mL with good accuracy and precision. The method was applied for transport experiments of Mtf across Caco-2 cells in the presence and absence of organic anions. Apparent permeability coefficients (Papp) were calculated. The Papp of Mtf was increased in the presence of CA and DS from 3.37×10-6 cm/s to 5.08×10-6 and 4.25×10-6 cm/s respectively, while it was decreased to 1.9×10-6 cm/s (p-value 0.01) in the presence of HCA. Interestingly, the Papp for Mtf increased more than four-fold when present with both calcium and CA together, which might lead to significant improvement in the bioavailability of the drug

Colloidal Stability and Cytotoxicity of Polydopamine-Conjugated Gold Nanorods against Prostate Cancer Cell Lines

Prostate cancer is one of the most common cancers in men. Cell invasion is an important step in the process of cancer metastasis. Herein, gold nanorods (GNRs) and polyethylene glycol (PEG)-coated GNRs were conjugated with polydopamine (PDA). The PDA-nanoconjugates demonstrated excellent colloidal stability upon lyophilization and dispersion in cell culture media with or without the addition of fetal bovine albumin (FBS), compared to unconjugated GNRs. PDA-nanoconjugates exhibited a considerable cytotoxicity against DU-145 and PC3 prostate cancer cell lines over a concentration range of 48 μg/mL–12 μg/mL, while they were biocompatible over a concentration range of 3.0 μg/mL–0.185 μg/mL. Furthermore, PDA-nanoconjugates demonstrated possible anti-invasion activity towards prostate cancer cell lines, particularly DU-145 cell line, by reducing cell migration and cell adhesion properties. The PDA-nanoconjugates could be considered a promising nano-platform toward cancer treatment by reducing the invasion activity; it could also be considered a drug delivery system for chemotherapeutic agents

Part VIII [1]. Convenient Synthesis and Antimicrobial Properties of Substituted Hexahydro[1,4]diazepino[2,3h]quinoline-9-carboxylic acid and Its Tetrahydroquino[7,8b]benzodiazepine Analog

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