Metformin Treatment Has No Beneficial Effect in a Dose-Response Survival Study in the SOD1G93A Mouse Model of ALS and Is Harmful in Female Mice

Background: Amyotrophic Lateral Sclerosis (ALS) is a devastating neurological disorder characterized by selective degeneration of upper and lower motor neurons. The primary triggers for motor neuron degeneration are unknown but inflammation, oxidative stress and mitochondrial defects have been identified as potential contributing factors. Metformin is an anti-type II diabetes drug that has anti-inflammatory and anti-oxidant properties, can bring about mitochondrial biogenesis and has been shown to attenuate pathology in mouse models of Huntington’s disease and multiple sclerosis. We therefore hypothesized that it might increase survival in the SOD1G93A murine model of ALS. Methodology/Principal Findings: Treatment of male and female SOD1G93A mice (n = $6 per sex) with 2 mg/ml metformin in the drinking water from 35 days, resulted in a significant increase in motor unit survival, as measured by in vivo electrophysiology at 100 days, in male EDL muscles (24+/22 vs. 14+/22 motor units, p,0.005) and female TA muscles (21+/ 21 vs. 15+/22 motor units, P = 0.0134). We therefore continued to test the effect of 0.5, 2 and 5 mg/ml metformin in the drinking water from 35 days on disease onset and progression (identified by twice weekly determination of weight and neurological score) as well as survival in male and female SOD1G93A mice (n =$14 per sex). Results for all groups were compared using Kaplan-Meier time to event analyses. In this survival study, metformin was unable to reduce pathology at any dose and had an unexpected dose-dependent negative effect on the onset of neurological symptoms (P = 0.0236) and on disease progression (P = 0.0362) in female mice. Conclusions/Significance: This study suggests that metformin is a poor candidate for clinical trial in ALS patients and that the possibility of harmful effects of metformin in female ALS patients with type II diabetes should be investigated

Optimization of the detection of microbes in blood from immunocompromised patients with haematological malignancies

AbstractThe present study aimed to improve the rate of detection of blood-borne microbes by using PCRs with pan-bacterial and Candida specificity. Seventeen per cent of the blood samples (n = 178) collected from 107 febrile patients with haematological malignancies were positive using standard culture (BacT/Alert system). Candida PCR was positive in 12 patients, only one of whom scored culture-positive. Bacterial PCR using fresh blood samples was often negative, but the detection rate increased when the blood was pre-incubated for 2 days. These data indicate that PCR assays might be a complement for the detection of blood-borne opportunists in immunocompromised haematology patients

Organization of Patient Management and Fungal Epidemiology in Cystic Fibrosis

The achievement of a better life for cystic fibrosis (CF) patients is mainly caused by a better management and infection control over the last three decades. Herein, we want to summarize the cornerstones for an effective management of CF patients and to give an overview of the knowledge about the fungal epidemiology in this clinical context in Europe. Data from a retrospective analysis encompassing 66,616 samples from 3235 CF patients followed-up in 9 CF centers from different European countries are shown

Hybrid Shell Engineering of Animal Cells for Immune Protections and Regulation of Drug Delivery: Towards the Design of “Artificial Organs”

BACKGROUND: With the progress in medicine, the average human life expectancy is continuously increasing. At the same time, the number of patients who require full organ transplantations is augmenting. Consequently, new strategies for cell transplantation are the subject of great interest. METHODOLOGY/PRINCIPAL FINDINGS: This work reports the design, the synthesis and the characterisation of robust and biocompatible mineralised beads composed of two layers: an alginate-silica composite core and a Ca-alginate layer. The adequate choice of materials was achieved through cytotoxicity LDH release measurement and in vitro inflammatory assay (IL-8) to meet the biocompatibility requirements for medical purpose. The results obtained following this strategy provide a direct proof of the total innocuity of silica and alginate networks for human cells as underscored by the non-activation of immune defenders (THP-1 monocytes). The accessible pore size diameter of the mineralised beads synthesized was estimated between 22 and 30 nm, as required for efficient immuno-isolation without preventing the diffusion of nutrients and metabolites. The model human cells, HepG2, entrapped within these hybrid beads display a high survival rate over more than six weeks according to the measurements of intracellular enzymatic activity, respiration rate, as well as the "de novo" biosynthesis and secretion of albumin out of the beads. CONCLUSIONS/SIGNIFICANCE: The current study shows that active mammalian cells can be protected by a silica-alginate hybrid shell-like system. The functionality of the cell strain can be maintained. Consequently, cells coated with an artificial and a biocompatible mineral shell could respond physiologically within the human body in order to deliver therapeutic agents in a controlled fashion (i.e. insulin), substituting the declining organ functions of the patient

Enzymatic Mechanisms Involved in Evasion of Fungi to the Oxidative Stress: Focus on Scedosporium apiospermum

The airways of patients with cystic fibrosis (CF) are frequently colonized by various filamentous fungi, mainly Aspergillus fumigatus and Scedosporium species. To establish within the respiratory tract and cause an infection, these opportunistic fungi express pathogenic factors allowing adherence to the host tissues, uptake of extracellular iron, or evasion to the host immune response. During the colonization process, inhaled conidia and the subsequent hyphae are exposed to reactive oxygen species (ROS) and reactive nitrogen species (RNS) released by phagocytic cells, which cause in the fungal cells an oxidative stress and a nitrosative stress, respectively. To cope with these constraints, fungal pathogens have developed various mechanisms that protect the fungus against ROS and RNS, including enzymatic antioxidant systems. In this review, we summarize the different works performed on ROS- and RNS-detoxifying enzymes in fungi commonly encountered in the airways of CF patients and highlight their role in pathogenesis of the airway colonization or respiratory infections. The potential of these enzymes as serodiagnostic tools is also emphasized. In addition, taking advantage of the recent availability of the whole genome sequence of S. apiospermum, we identified the various genes encoding ROS- and RNS-detoxifying enzymes, which pave the way for future investigations on the role of these enzymes in pathogenesis of these emerging species since they may constitute new therapeutics targets

Circulating β (1-3) Glucan and Immunoglobulin G Subclass Antibodies to Candida albicans Cell Wall Antigens in Patients with Systemic Candidiasis

Invasive candidiasis in patients who are immunocompromised or in intensive care units (ICUs) presents both diagnostic and therapeutic problems. We previously described antibodies that were directed against Candida albicans cell wall fragments (CW), periodate-treated CW (CW(IO4)), phosphopeptidomannan (PPM), and β(1-3) glucan. In this study, circulating fungal antigens [mannan and β(1-3) glucan] and immunoglobulin G (IgG) subclass antibodies to these cell wall antigens (anti-CW) were analyzed in patients with systemic candidiasis. Sera were collected from 14 patients on two or three consecutive occasions, starting on the day when candidiasis was culture proven. The sera were analyzed by enzyme-linked immunosorbent assay. The control groups consisted of lactating mothers (n = 9) (group I) who had breast milk that was positive for C. albicans and also had acute inflammation of the nipples, and age-matched blood donors (n = 10) (group II). Within the first 3 weeks of Candida infection all of the patients were positive for β(1-3) glucan by the Gluspecy test, but no patients were positive for mannan in the less-sensitive Pastorex Candida test. The controls were negative for both β(1-3) glucan (<20 pg/ml) and mannan (<2.5 ng/ml). IgG1 anti-CW and IgG2 anti-PPM antibodies were the most discriminatory antibodies. The ratio of IgG1 anti-CW to IgG2 anti-PPM was significantly lower in nonsurviving patients than in the other patients within the first week of candidiasis (P = 0.019). The IgG2 levels of anti-CW(IO4) and antiglucan antibodies correlated strongly (r = 0.681; P < 0.0001), and the absence of these antibodies was associated with increased levels of β(1-3) glucan. Increased levels of IgG1 anti-CW or IgG2 anti-PPM antibodies (titer of ≥3 logs) or of a combination of the two antibodies (log sum, ≥5) showed 92% sensitivity, 100% specificity, and positive predictive values. In conclusion, β(1-3) glucan and the two subclass antibodies appear to be early specific markers for the laboratory diagnosis of candidiasis. Furthermore, the kinetics of β(1-3) glucan appearance in serum may assist in evaluating the therapeutic efficacy of antifungal treatments

Synthesis, X-ray structural analysis, antibacterial and DNA-binding studies of a lanthanum bis-(5,5′-dimethyl-2,2′-bipyridine) complex

A new complex with the formula [La(5,5′-dmbpy) 2 (NO 3 ) 3 ] (a) [where (5,5′-dmbpy = 5,5′-dimethyl-2,2′-bipyridine)] has been synthesized. The compound was characterized by cyclic voltammetry, elemental analysis and spectroscopic methods (IR, UV–Vis, 1 H-NMR). Single crystals adapted for X-ray diffraction analysis were recorded by slow crystallization from a methanol solution. The complex is neutral being the lanthanum cation chelated by two bipyridine derivative neutral ligands and three bidentate nitrate groups. Electronic spectra show the transition of both ligand field and charge transfer bands. The fluorescence properties of the compound have been studied. The interactions of complex with FS-DNA (salmon sperm DNA) have been studied using UV–Vis, fluorescence spectroscopies and gel electrophoresis. The above-mentioned techniques were used in physiological buffer having pH 7.2. The binding constant (K b ) for interaction in (a) with DNA was obtained using UV–Vis spectroscopies (K b = 1.2 × 10 5 ) and fluorescence spectroscopies (K b = 1.50 × 10 5 ). The binding constant (K b ), the number of binding sites for each 1000 nucleotides (n) and the apparent bio molecular quenching constant (k q ) for FS-DNA were obtained through Stern–Volmer equation. Thermodynamic parameters data (∆H°, ΔS° and ΔG°) showed that hydrogen bonding and van der Waals interactions have an important function in the interaction of DNA–La(III) complex, and the binding mode is the groove binding. The DNA binding of La(III) complex is spontaneous as suggested by the negative ΔG°. Moreover, the DNA cleavage has been studied using agarose gel electrophoresis. The antibacterial effects of complex (a) have also been examined in vitro against standard bacterial strains

Screen-printed electrode modified with Co-NPs, as an electrochemical sensor for simultaneous determination of doxorubicin and dasatinib

The new metal complex of Co(II) (a1) and its nano-size, (a2), with NCS− and 5,5´-dimethyl-2,2´-bipyridine ligands have been synthesized. [Co(5,5´-dmbpy)3][Co(NCS)4] (a1) characterized through spectroscopic methods such as FTIR, UV–Vis, diffractometric analysis and elemental analysis. Nanoparticle (a2) has been identified with FTIR spectroscopy, also SEM, and XRD techniques. The size of the (a2) is about 86&nbsp;nm. In this study, an electrochemical sensing platform for simultaneous detection of doxorubicin and dasatinib based on screen-printed electrode (SPE) modified with (a2) was prepared. The modified SPE, on the contrary to bare SPE, can considerably enhance activities of electrocatalytic towards oxidation of doxorubicin and dasatinib, followed by rising the anodic peak current. Peak currents obtained via differential pulse voltammetry (DPV) showed a linear enhancement as dasatinib concentration elevated and sensor detected in ranges more than that of the concentration limited area of 0.04–195.0&nbsp;μM, detection limit equal to 12.0&nbsp;nM (S/N = 3). DPV responses show that at the&nbsp;surface of modified SPE, obvious separation of the peak of doxorubicin and dasatinib oxidation has been reported from another with 400&nbsp;mV potential difference between them. A lower limit of detection (LOD), higher sensitivity as well as stability resulted in an electrode that could be applied for analyzing different real compounds. Moreover, its functionality is favorable and desirable in analyzing biological fluids and drug compounds