Improving Type 2 Diabetes Care with Extended-Release Metformin: Real-Life Insights from a Physician Educational Program.

BACKGROUND: Compared to Immediate-Release (IR) metformin, Extended-Release (ER) metformin reduces side effects and pill burden while improving adherence; however, there is little real-life data on patient satisfaction with this innovative formulation to guide physicians toward a more holistic approach. OBJECTIVE: Our goal is to train general practitioners on holistic patient management, with the aim of increasing patient satisfaction and treatment adherence, reducing side effects, and improving quality of life in patients with poor tolerance to metformin-IR. DESIGN AND METHODS: We designed an educational program for physicians called SlowDiab, aimed at establishing a holistic patient approach. In this context, adult patients with T2DM who experienced gastrointestinal discomfort with metformin-IR were enrolled and switched to metformin- ER. Data on glycemic control were collected at baseline and 2 months after switching. A survey was carried out on patients to assess their level of satisfaction. RESULTS: In 69 enrolled patients (mean [min-max] age, 68.2 [41-90]), side effects decreased after switching from 61.8% to 16.2% (p < 0.01), and the mean perceived burden of adverse events on a scale of 1 to 10 also decreased (6.17 vs. 3.82; p < 0.05). Among patients previously intolerant to metformin-IR, 74.3% reported no longer experiencing any side effects after the switch. The mean number of tablets taken daily (2.28 vs. 1.66; p < 0.01) and mean plasma glycated hemoglobin (HbA1c) values (7.0% vs. 6.7%; p < 0.05) decreased, while 93.8% of patients were satisfied with the treatment change. Moreover, 84.2% reported an improvement in glycemic control after the switch. CONCLUSION: In a real-life setting, an educational program for general practitioners confirmed that metformin ER reduces side effects and improves pill burden, therapeutic adherence, and patient satisfaction compared to metformin IR.

The Acinetobacter Outer Membrane Contains Multiple Specific Channels for Carbapenem ß-Lactams as Revealed by Kinetic Characterization Analyses of Imipenem Permeation into Acinetobacter baylyi Cells.

The number and type of outer membrane (OM) channels responsible for carbapenem uptake in Acinetobacter are still not well defined. Here, we addressed these questions by using Acinetobacter baylyi as a model species and a combination of methodologies aimed to characterize OM channels in their original membrane environment. Kinetic and competition analyses of imipenem (IPM) uptake by A. baylyi whole cells allowed us to identify different carbapenem-specific OM uptake sites. Comparative analyses of IPM uptake by A. baylyi wild-type (WT) cells and ΔcarO mutants lacking CarO indicated that this OM protein provided a carbapenem uptake site displaying saturable kinetics and common binding sites for basic amino acids compatible with a specific channel. The kinetic analysis uncovered another carbapenem-specific channel displaying a somewhat lower affinity for IPM than that of CarO and, in addition, common binding sites for basic amino acids as determined by competition studies. The use of A. baylyi gene deletion mutants lacking OM proteins proposed to function in carbapenem uptake in Acinetobacter baumannii indicated that CarO and OprD/OccAB1 mutants displayed low but consistent reductions in susceptibility to different carbapenems, including IPM, meropenem, and ertapenem. These two mutants also showed impaired growth on l-Arg but not on other carbon sources, further supporting a role of CarO and OprD/OccAB1 in basic amino acid and carbapenem uptake. A multiple-carbapenem-channel scenario may provide clues to our understanding of the contribution of OM channel loss or mutation to the carbapenem-resistant phenotype evolved by pathogenic members of the Acinetobacter genus.

Draft Genome Sequence of Acinetobacter bereziniae HPC229, a Carbapenem-Resistant Clinical Strain from Argentina Harboring blaNDM-1.

We report here the draft genome sequence of an NDM-1-producing Acinetobacter bereziniae clinical strain, HPC229. This strain harbors both plasmid and chromosomal resistance determinants toward different ß-lactams and aminoglycosides as well as several types of multidrug efflux pumps, most likely representing an adaptation strategy for survival under different environments.

The complete nucleotide sequence of the carbapenem resistance-conferring conjugative plasmid pLD209 from a Pseudomonas putida clinical strain reveals a chimeric design formed by modules derived from both environmental and clinical bacteria.

The complete sequence of the carbapenem-resistance-conferring conjugative plasmid pLD209 from a Pseudomonas putida clinical strain is presented. pLD209 is formed by 3 well-defined regions: an adaptability module encompassing a Tn402-like class 1 integron of clinical origin containing blaVIM-2 and aacA4 gene cassettes, partitioning and transfer modules, and a replication module derived from plasmids of environmental bacteria. pLD209 is thus a mosaic of modules originating in both the clinical and environmental (nonclinical) microbiota.

Expression of the Escherichia coli ompW colicin S4 receptor gene is regulated by temperature and modulated by the H-NS and StpA nucleoid-associated proteins.

The OmpW family consists of a ubiquitous group of small outer membrane (OM) ß-barrel proteins of Gram-negative bacteria with proposed roles in environmental adaptation but poorly understood mechanisms of expression. We report here that Escherichia coli K-12 OmpW contents are drastically modified by temperature changes compatible with the leap from the environment to warm-blooded hosts and/or vice versa. Thus, while OmpW is present in the OM of bacteria grown at 37 °C, it sharply disappears at 23 °C with the concomitant acquisition of colicin S4 resistance by the cells. ompW::lacZY fusions indicated that temperature regulation operates at the level of transcription, being ompW expression almost abolished at 23 °C as compared to 37 °C. Moreover, E. coli Δhns mutants lacking H-NS showed reductions in ompW transcription and OmpW contents at 37 °C, indicating positive modulatory roles for this nucleoid-structuring protein in ompW expression. Also, ΔhnsΔstpA double mutants simultaneously lacking H-NS and its paralog StpA showed more severe reductions in ompW expression at 37 °C, resulting in the complete loss of OmpW. The overall results indicate that OmpW contents in E. coli are regulated by both temperature and H-NS and reinforce OmpW functions in bacterial adaptation to warm-blooded hosts.

Low-molecular-mass penicillin binding protein 6b (DacD) is required for efficient GOB-18 metallo-ß-lactamase biogenesis in Salmonella enterica and Escherichia coli.

Metallo-ß-lactamases (MBLs) are Zn(2+)-containing secretory enzymes of clinical relevance, whose final folding and metal ion assembly steps in Gram-negative bacteria occur after secretion of the apo form to the periplasmic space. In the search of periplasmic factors assisting MBL biogenesis, we found that dacD null (ΔdacD) mutants of Salmonella enterica and Escherichia coli expressing the pre-GOB-18 MBL gene from plasmids showed significantly reduced resistance to cefotaxime and concomitant lower accumulation of GOB-18 in the periplasm. This reduced accumulation of GOB-18 resulted from increased accessibility to proteolytic attack in the periplasm, suggesting that the lack of DacD negatively affects the stability of secreted apo MBL forms. Moreover, ΔdacD mutants of S. enterica and E. coli showed an altered ability to develop biofilm growth. DacD is a widely distributed low-molecular-mass (LMM) penicillin binding protein (PBP6b) endowed with low dd-carboxypeptidase activity whose functions are still obscure. Our results indicate roles for DacD in assisting biogenesis of particular secretory macromolecules in Gram-negative bacteria and represent to our knowledge the first reported phenotypes for bacterial mutants lacking this LMM PBP.