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The relationship between periodontal disease and diabetes mellitus

Abstract

Periodontitis is a common complication in patients with diabetes. Their classification is complex and it is based on the clinical presentation, rate of disease progression, age at diagnosis and local and systemic factors that may multiply the risk. The two major stages of periodontal diseases are gingivitis and periodontitis. The relationship between these two diseases appears bidirectional insofar that the existence of one disease tends to promote the other and that the meticulous management of either may help the treatment of the other. Treatment of periodontitis using a association of mechanical therapy, scaling and root planning, plus systemic tetracycline antibiotics has been demonstrated to have important reductions in HbA1c values. Therefore, for a better control of diabetes we suggest that periodontal patients with diabetes should be consulted and treated by a periodontist.

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LC-MS/MS analysis of doxycycline residues in chicken tissues after oral administration

-residue analysis of tetracyclines and their 4-epimers in pig tissues by high-performance liquid chromatography combined with positive-ion electrospray ionization mass spectrometry. Anal Chim Acta 2003, 492, 199-213. 5. Cinquina A.L., Longo F., Anastasi G., Giannetti L., Cozzania R.: Validation of a high - performance liquid chromatography method for the determination of oxytetracycline, tetracycline, chlortetracycline and doxycycline in bovine milk and muscle. J Chromatogr A 2003, 987, 227-233. 6. Crivineanu M., Trifan V., Paraschiv G

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An experimental in-vitro study to evaluate the anti-helicobacter activity of Glycyrrhetinic acid

Abstract

Aim: The aim of this study was to investigate the in-vitro efficacy of Glycyrrhetinic acid against Helicobacter pylori (H. pylori) strains, as compared with conventional antibacterial agents.

Methods: A total of 41 H. pylori isolates were used, 6 of which were of standard strains (NCTC 1637), 8 of which were drug-sensitive, and 27 were resistant to drugs isolates. Clarithromycin and metronidazole resistance in all strains of H. pylori were determined by the Epsilometer test (E-test) method. MIC study was performed by using microdilution broth method.

Results: Glycyrrhetinic acid was found to be effective against H. pylori NCTC 1637 in doses of 12.0±4.38 µg/mL, while the MIC value of clinical H. pylori isolates susceptible to antimicrobials was 20.8±10.11 µg/ml. It was found that the MIC values for antimicrobial-sensitive clinical H. pylori isolates was higher when compared with H. pylori NCTC 1637 strains. The MIC values of the standard antimicrobial agents against drug-resistant H. pylori strains were higher than H. pylori NCTC 1637 strains and drug-sensitive H. pylori strains. The MIC value was found to be 14.22±7.77 µg/ml for metronidazole, 3.89±1.90 µg/ml for clarithromycin, 2.33±1.0 µg/ml for amoxicillin, 2.44±0.88 µg/ml for levofloxacin and 4.89±2.47 µg/ml for tetracycline, whereas the MIC value of Glycyrrhetinic acid was 26.67±8.0 µg/ml in metronidazole-resistant H. pylori isolates. Besides, MIC values of the antimicrobials and 18ß-Glycyrrhetinic acid among the strains resistant to clarithromycin were as follows: 3.25±2.12 µg/ml for metronidazole, 9.71±4.54 µg/ml for clarithromycin, 2.06±1.32 µg/ml for amoxicillin, 3.88±4.22 µg/ml for levofloaxacin and 3.25±1.04 µg/mL for tetracycline and 22.0±11.11 µg/ml for Glycyrrhetinic acid.

Conclusion: Glycyrrhetinic acid had significant antimicrobial activity against H. pylori strains. Although further in-vivo studies are needed on antimicrobial activity of Glycyrrhetinic acid, increased resistance to drugs currently used in treatment suggests that Glycyrrhetinic acid may be a potential agent for the treatment of H. pylori.

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Immunomodulatory and anti-inflammatory properties of macrolides

References 1. Altenburg J. et al.: Immunomodulatory effects of macrolide antibiotic- part 1: biological mechanisms. Respiration, 81, 67, 2011. 2. Cazalias J., Tanabe S., Gagnon G.: Tetracyclines and chemically modified tetracycline-3 (CMT-3) modulate cytokine secretion by lipopolysaccharide-stimulated whole blood. Inflammation, 32, 130, 2009. 3. Culic O., Erakovic V., Parnham M.J.: Anti-inflammatory effects of macrolide antibiotics. Eur. J. Pharmacol., 429, 209, 2001. 4. Friedlander A.L., Albert

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Faecal indicator bacteria and antibiotic-resistant β-lactamase producing Escherichia coli in blackwater: a pilot study

Abstract

The aim of this study was to identify and quantify faecal indicator bacteria in blackwater collected from a source separation unit and determine the amount of E. coli isolates resistant to antimicrobials and their potential to produce extended spectrum β-lactamases (ESβLs) and metallo-β-lactamases (MβLs), which hydrolyse the most important antibiotics used in clinical practice. Most of the isolates were resistant to amoxicillin with clavulanic acid (36.4 %), followed by ticarcillin with clavulanic acid (22.7 %) and tetracycline (18.2 %). ESβL-producing genes bla CTX-M and bla TEM were found in three (13.6 %) and four (18.2 %) E. coli strains, respectively, while MβL genes were found in two (9.1 %). By separating at source, this pilot study clearly shows that gastrointestinal bacteria of healthy people can be an important source of antibiotic resistance released into the environment through wastewaters. One way to prevent that is to treat wastewater with a combination of TiO2, UV light, or ozone, as successful methods to remove resistant bacteria and prevent their spread in the environment.

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Virulence factors and mechanisms of antibiotic resistance of haemophilus influenzae

ABSTRACT

Haemophilus influenzae is a small gram-negative coccobacillus known as one of the major causes of meningitis, otitis media, sinusitis and epiglottitis, especially in childhood, as well as infections of the lower respiratory tract, eye infections and bacteremia. It has several virulence factors that play a crucial role in patient infl ammatory response. Its capsule, the adhesion proteins, pili, the outer membrane proteins, the IgA1 protease and, last but not least, the lipooligosaccharide, increase the virulence of H. infl uenzae by participating actively in the host invasion the host by the microrganism. Some of these factors are used in vaccine preparations. In the post-vaccine era, an increase has been noticed in many European countries of invasive infections caused by non-encapsulated strains of H. influenzae which have a number of virulence factors, some of which are subject of serious research aiming at creating new vaccines. Numerous mechanisms of antibiotic resistance in H. infl uenzae are known which can compromise the empirical treatment of infections caused by this microorganism. The increasing incidence of resistance to aminopenicillins, induced not only by enzyme mechanisms but also by a change of their target is turning into a signifi cant problem. Resistance to other antibiotics such as macrolides, tetracyclines, chloramphenicol, trimethoprim/sulfamethoxazole, and fl uoroquinolones, commonly used to treat Haemophilus infections has also been described.

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Changes in Antibiotic Susceptibility Pattern of Atypical Staphylococcus Aureus Strains Isolated from Cows of the same Herd in 2008-2010

Abstract

The isolates of Staphylococcus aureus strains were examined phenotypically by cultural features, tube coagulase test and clumping factor (CF), and genotypically by conventional PCR. The strains had positive reaction in CF test, but were negative in tube coagulase test. The analysed strains from the same cows in each year expressed also nuc and coa genes. About 25% of the strains were examined by the disc diffusion method for their sensitivity to antibiotics. During three years, the strains were highly susceptible in vitro to amoxicillin with clavulanic acid, oxacillin, bacitracin, and cefoperazone (more than 90%), and highly resistant to tetracycline, neomycin, and streptomycin. Forty randomly chosen strains, and eight strains from the same cows in each year were analysed for minimal inhibitory concentration of penicillin G using microdilution method. An increasing resistance to the penicillin was noted. Moreover, eight strains, the same in each year, were also examined for β-lactamase production and methicillin resistance. No β-lactamase producers and no methicillin resistant strains were found using phenotypic and genotypic methods. In conclusion, it can be stated that antimicrobial susceptibility can change from one year to another.

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ERIC-based differentiation and antimicrobial susceptibility of Yersinia enterocolitica O:9 isolated from animals serologically positive and negative for brucellosis

Abstract

The paper presents the results of genotypic differentiation and antimicrobial susceptibility of Y. enterocolitica O:9 isolates that originated from cows and pigs positive in serological reactions for brucellosis, and also from the animals, which were serologically negative. The genetic relationship between Y. enterocolitica O:9 isolates originating from different sources was determined by the use of ERIC-PCR, and resulted in detection of 6 to 13 DNA amplicons of different size. The clonal analysis was based on dendrogram created by Unweighted Pair Group Method with arithmetic mean and Jaccard’s coefficient, which enabled to divide Y. enterocolitica O:9 isolates into 16 different clonal groups. Among all Y. enterocolitica O:9, MIC value was >32 mg/L for the ampicillin, ≤0.008 mg/L for ciprofloxacin, ≤8 mg/L for sulphametoxazole, ≤2 mg/L for colistin, and ≤1 mg/L for tetracycline. The wide range of MIC for ceftazidime (≤0.25-2 mg/L) and cefotaxime (≤0.06-1 mg/L) among Y. enterocolitica O:9 isolates was also observed. No significant differences were observed between MIC values of Y. enterocolitica O:9 isolates originating from animals serologically positive for brucellosis, and the isolates from cows and pigs, which provided serologically negative reactions.

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Molecular Characterization of ESBL-Producing Escherichia Coli Isolated from Healthy Cattle and Sheep

Abstract

The present study aims to characterize ESBL-producing Escherichia coli isolated from healthy cattle and sheep in the Burdur province of Turkey. Fecal samples from a total of 200 cattle and 200 sheep were tested and ESBL-producing E. coli was isolated from 31 (15.5%) cattle and three (1.5%) sheep samples using the Clinical and Laboratory Standards Institute’s combined disk method. Among the ESBL gene classes detected by PCR, blaCTX-M was the most frequent type, followed by the blaTEM and blaSHV families. ESBL-producing E. coli isolates showed co-resistance to multiple classes of antibiotics including aminoglycosides, phenicols, quinolones, folate pathway inhibitors and tetracyclines. The resistance rates were higher in the cattle isolates than in the sheep isolates. Phylogenetic grouping of the E. coli isolates indicated group A (particularly A1) was the predominant phylogenetic group (19/34, 55.9%), followed by groups B1 (9/34, 26.5%) and D (6/34, 17.6%); none of the isolates belonged to group B2. The study shows that ESBL-producing E. coli isolates exist in the intestinal flora of healthy cattle and sheep in the Burdur province of Turkey. This is the first report showing the emergence of CTX-M type ESBL-producing E. coli in sheep farms in Turkey

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Occurrence of enterococci in mastitic cow’s milk and their antimicrobial resistance

Abstract

Introduction: The aim of the study was to evaluate the occurrence of enterococci in inflammatory secretions from mastitic bovine udders and to assess their antimicrobial resistance.

Material and Methods: A total of 2,000 mastitic milk samples from cows were tested in 2014–2017. The isolation of enterococci was performed by precultivation in buffered peptone water, selective multiplication in a broth with sodium azide and cristal violet, and cultivation on Slanetz and Bartley agar. The identification of enterococci was carried out using Api rapid ID 32 strep kits. The antimicrobial susceptibility was evaluated using the MIC technique.

Results: Enterococci were isolated from 426 samples (21.3%). Enterococcus faecalis was the predominant species (360 strains), followed by E. faecium (35 isolates), and small numbers of others. The highest level of resistance was observed to lincomycin, tetracycline, quinupristin/dalfopristin (Synercid), erythromycin, kanamycin, streptomycin, chloramphenicol, and tylosin. Single strains were resistant to vancomycin and ciprofloxacin. All isolates were sensitive to daptomycin. E. faecalis presented a higher level of resistance in comparison to E. faecium, except to nitrofurantoin.

Conclusion: The results showed frequent occurrence of enterococci in mastitic cow’s milk and confirmed the high rate of their antimicrobial resistance.

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