scholarly journals SPECIES DIVERSITY AND SENSITIVITY TO ANTIBIOTICS AGAINST ORAL STREPTOCOCCI ISOLATED IN CHILDREN

2019 ◽  
Vol 22 (3) ◽  
pp. 153-161 ◽  
Author(s):  
N. A. Mayanskiy ◽  
A. Z. Kvarchiya ◽  
E. A. Brzhozovskaya ◽  
O. A. Ponomarenko ◽  
O. A. Kryzhanovskaya ◽  
...  
Keyword(s):  
Respiratory Infections ◽  
Multiple Drug Resistance ◽  
Genetic Material ◽  
Tetracycline Resistance ◽  
The Body ◽  
Multiple Drug ◽  
Species Structure ◽  
Oral Streptococci ◽  
Streptococcus Mitis ◽  
Wide Range

Oral streptococci can exchange genetic material with other bacteria colonizing the same loci of the body, their resistance profiles can serve as markers of the risk of the developing resistance to certain antibiotics in closely related bacteria, in particular, Streptococcus pneumoniae. Materials and Methods To describe the species composition of oral streptococci and to detect the profile of their sensitivity to a wide range of antibiotics there were investigated oral streptococcal isolates isolated from oropharyngeal smears sown in children of various ages with acute respiratory infections not receiving antibacterial therapy for selective streptococcal medium with penicillin (Pen, 1 mg/l) or erythromycin (Ery, 2 mg/l). 253 oropharyngeal smears were studied. Results. The most frequent sowings were Pen-resistant and Ery-resistant Streptococcus mitis, found in 158 (62.5%) and 169 (66.8%) studied, respectively. Ery-resistant Streptococcus salivarius group was detected in 107 (42.3%) samples, Pen-resistant streptococcus from this group were found much less frequently in 16 (6.3%) samples. Pen and Eri-resistant isolates of Streptococcus sanguinis group were present in 69 (27.3%) and 49 (19.4%) samples respectively. All the streptococcus specimens studied were sensitive to vancomycin, linezolid and (except for one) levofloxacin; about 90% were sensitive to daptomycin, rifampicin and chloramphenicol. Sensitivity to tetracycline was lower at 57.5%. Multiple drug resistance (MDR; resistance to ≥3 groups of antibiotics) had 93 (58.1%) isolates; the most common combination of penicillin, erythromycin and tetracycline resistance was found in 53 (57%) MDR isolates. Streptococcus mitis/oralis were characterized by higher MPCs of penicillin, ampicillin and ceftriaxone, as well as the frequency of stable forms, including MDR, as compared to other streptococci. Streptococcus mitis, first S. mitis oralis group streptococcus predominate in the species structure of antibiotic-resistant oral streptocococci, among which MDR is widespread, including resistance to β-lactams.

Spectrum and resistance determinants of oral streptococci clinical isolates

2020 ◽  
Vol 65 (10) ◽  
pp. 632-637
Author(s):  
Nataliia Valerievna Davidovich ◽  
A. S. Galieva ◽  
N. G. Davydova ◽  
O. G. Malygina ◽  
N. N. Kukalevskaya ◽  
...  
Keyword(s):  
Antimicrobial Agents ◽  
Multiple Drug Resistance ◽  
Antibiotic Sensitivity ◽  
Periodontal Pocket ◽  
Multiple Drug ◽  
Oral Streptococci ◽  
Antibiotic Resistant ◽  
Resistance Determinants ◽  
Wide Range ◽  
Clinically Significant

The profiles of oral streptococci sensitivity to antibacterial drugs may reflect information about the presence of macroorganism resistance determinants. The aim of the work was to isolate the spectrum of oral streptococci from the microbiota of the oral cavity of patients and to determine their sensitivity to a wide range of antibiotics. A total of 342 microbial streptococcal isolates were isolated from saliva samples and a periodontal pocket and tested for antibiotic sensitivity. Species identification of streptococci was carried out using biochemical API test systems. Evaluation of antibiotic resistance was performed using E-tests. Real-time PCR was used to identify the presence of tetracycline and macrolide resistance genes. The study identified six types of oral streptococci: S. oralis, S. salivarius, S. mitis, S. sanguinis, S. anginosus and S. mutans. All streptococci were sensitive to linezolid and meropenem. The proportion of penicillin-resistant streptococci in the subgroup S. oralis / mitis / mutans was 47,8% versus 23,5% in the subgroup S. salivarius / sanguinis / anginosus (p = 0.020). Significant levels of resistance were revealed to macrolides (erythromycin) - 47,9%, tetracyclines (tetracycline) - 44,4% and quinolones (ofloxacin) - 41%. Multiple drug resistance (MDR) was detected in 31,9% of oral streptococcal isolates, a combination of erythromycin, tetracycline and ofloxacin resistance was prevalent in 79 isolates (23,1%). The most common genotypes of macrolides and tetracycline resistant oral streptococci (in 127 streptococcal isolates with combined resistance) were ermB-mefE + and tetM + tetQ-, respectively. Thus, S. oralis / mitis / mutans group streptococci predominated in the structure of antibiotic-resistant oral streptococci, including MDR. So, being in one of the most densely populated biotopes of a macroorganism, oral streptococci can mediate the transfer of resistance determinants to more pathogenic and clinically significant microorganisms, which requires careful monitoring of their level of susceptibility to antimicrobial agents.

scholarly journals In Situ Biochemical Demonstration That P-Glycoprotein Is a Drug Efflux Pump with Broad Specificity

2000 ◽  
Vol 148 (5) ◽  
pp. 863-870 ◽  
Author(s):  
Yu Chen ◽  
Sanford M. Simon
Keyword(s):  
Fluorescent Protein ◽  
Efflux Pump ◽  
Multiple Drug Resistance ◽  
Living Cells ◽  
Drug Accumulation ◽  
Multiple Drug ◽  
Gfp Expression ◽  
Active Efflux ◽  
P Glycoprotein ◽  
Wide Range

While P-glycoprotein (Pgp) is the most studied protein involved in resistance to anti-cancer drugs, its mechanism of action is still under debate. Studies of Pgp have used cell lines selected with chemotherapeutics which may have developed many mechanisms of resistance. To eliminate the confounding effects of drug selection on understanding the action of Pgp, we studied cells transiently transfected with a Pgp-green fluorescent protein (GFP) fusion protein. This method generated a mixed population of unselected cells with a wide range of Pgp-GFP expression levels and allowed simultaneous measurements of Pgp level and drug accumulation in living cells. The results showed that Pgp-GFP expression was inversely related to the accumulation of chemotherapeutic drugs. The reduction in drug concentration was reversed by agents that block multiple drug resistance (MDR) and by the UIC2 anti-Pgp antibody. Quantitative analysis revealed an inverse linear relationship between the fluorescence of Pgp-GFP and MDR dyes. This suggests that Pgp levels alone limit drug accumulation by active efflux; cooperativity between enzyme, substrate, or inhibitor molecules is not required. Additionally, Pgp-GFP expression did not change cellular pH. Our study demonstrates the value of using GFP fusion proteins for quantitative biochemistry in living cells.

scholarly journals The Use of Viral Vectors in Gene Transfer Therapy

2016 ◽  
Vol 8 (03) ◽  
Author(s):  
A. Dziaková ◽  
A. Valenčáková ◽  
E. Hatalová ◽  
J. Kalinová
Keyword(s):  
Gene Therapy ◽  
Plasmid Dna ◽  
Clinical Studies ◽  
Viral Vectors ◽  
Disease Gene ◽  
Major Gene ◽  
Genetic Material ◽  
The Body ◽  
Disease Genes ◽  
Wide Range

Gene therapy is strategy based on using genes as pharmaceuticals. Gene therapy is a treatment that involves altering the genes inside body's cells to stop disease. Genes contain DNA- the code controlling body form and function. Genes that do not work properly can cause disease. Gene therapy replaces a faulty gene or adds a new gene in an attempt to cure disease or improve the ability of the body to fight disease. Gene therapy holds promise for treating a wide range of diseases, including cancer, cystic fibrosis, heart disease, diabetes, hemophilia and AIDS. Various types of genetic material are used in gene therapy; double-stranded DNA (dsDNA), single-stranded DNA (ssDNA), plasmid DNA and antisense oligodeoxynucleotides (ASON). The success of gene therapy depends on assuring the entrance of the therapeutic gene to targeted cells without any form of biodegradation. Commonly used vectors in gene therapy are: adenoviruses (400 clinical studies; 23.8%), retroviruses (344 clinical studies; 20.5%), unenveloped/plasmid DNA (304 clinical studies, 17.7%), adenoassociated viruses (75 clinical studies; 4.5%) and others. In this paper, we have reviewed the major gene delivery vectors and recent improvements made in their design meant to overcome the issues that commonly arise with the use of gene therapy vectors.

scholarly journals DNA-mediated transfer of multiple drug resistance and plasma membrane glycoprotein expression.

1982 ◽  
Vol 2 (8) ◽  
pp. 881-889 ◽  
Author(s):  
P G Debenham ◽  
N Kartner ◽  
L Siminovitch ◽  
J R Riordan ◽  
V Ling
Keyword(s):  
Drug Resistance ◽  
Plasma Membranes ◽  
Multiple Drug Resistance ◽  
Chinese Hamster ◽  
Surface Glycoprotein ◽  
Multiple Drug ◽  
Cell Surface Glycoprotein ◽  
Resistance Phenotype ◽  
P Glycoprotein ◽  
Wide Range

Colchicine-resistant Chinese hamster ovary (CHO) cell mutants whose resistance results from reduced drug permeability have been isolated previously in our laboratories. This reduced permeability affects a wide range of unrelated drugs, resulting in the mutants displaying a multiple drug resistance phenotype. A 170,000-dalton cell surface glycoprotein (P-glycoprotein) was identified, and its expression appears to correlate with the degree of resistance. In this study we were able to confer the multiple drug resistance phenotype on sensitive mouse L cells by DNA-mediated gene transfer of DNA obtained from the colchicine-resistant mutants. P-glycoprotein was detected in plasma membranes of these DNA transformants by staining with an antiserum raised against membranes of mutant CHO cells. These results are consistent with a causal relationship between P-glycoprotein expression and the multiple drug resistance phenotype.

DNA-mediated transfer of multiple drug resistance and plasma membrane glycoprotein expression

1982 ◽  
Vol 2 (8) ◽  
pp. 881-889
Author(s):  
P G Debenham ◽  
N Kartner ◽  
L Siminovitch ◽  
J R Riordan ◽  
V Ling
Keyword(s):  
Drug Resistance ◽  
Plasma Membranes ◽  
Multiple Drug Resistance ◽  
Chinese Hamster ◽  
Surface Glycoprotein ◽  
Multiple Drug ◽  
Cell Surface Glycoprotein ◽  
Resistance Phenotype ◽  
P Glycoprotein ◽  
Wide Range

Colchicine-resistant Chinese hamster ovary (CHO) cell mutants whose resistance results from reduced drug permeability have been isolated previously in our laboratories. This reduced permeability affects a wide range of unrelated drugs, resulting in the mutants displaying a multiple drug resistance phenotype. A 170,000-dalton cell surface glycoprotein (P-glycoprotein) was identified, and its expression appears to correlate with the degree of resistance. In this study we were able to confer the multiple drug resistance phenotype on sensitive mouse L cells by DNA-mediated gene transfer of DNA obtained from the colchicine-resistant mutants. P-glycoprotein was detected in plasma membranes of these DNA transformants by staining with an antiserum raised against membranes of mutant CHO cells. These results are consistent with a causal relationship between P-glycoprotein expression and the multiple drug resistance phenotype.

scholarly journals Clostridioides difficile in Calves in Central Italy: Prevalence, Molecular Typing, Antimicrobial Susceptibility and Association with Antibiotic Administration

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 515
Author(s):  
Francesca Blasi ◽  
Carmela Lovito ◽  
Elisa Albini ◽  
Luca Bano ◽  
Gastone Dalmonte ◽  
...  
Keyword(s):  
Multiple Drug Resistance ◽  
Central Italy ◽  
Tetracycline Resistance ◽  
Cross Sectional Study ◽  
Multiple Drug ◽  
Antibiotic Administration ◽  
Cross Sectional ◽  
Clostridioides Difficile ◽  
Resistant Strains ◽  
Cattle Farms

The emergence of Clostridioides difficile as the main agent of antibiotic-associated diarrhoea has raised concerns about its potential zoonotic role in different animal species. The use of antimicrobials is a major risk factor for C. difficile infection. Here, we provide data on C. difficile infection in dairy and beef calves in Umbria, a region in central Italy. This cross-sectional study focuses on prevalence, risk factors, ribotypes, toxinotypes and antimicrobial resistance profiles of circulating ribotypes. A prevalence of 19.8% (CI95%, 12–27.6%) positive farms was estimated, and the prescription of penicillins on the farms was associated with C. difficile detection (OR = 5.58). Eleven different ribotypes were found, including the ST11 sublineages RT-126 and -078, which are also commonly reported in humans. Thirteen isolates out of 17 showed resistance to at least one of clindamycin, moxifloxacin, linezolid and vancomycin. Among them, multiple-drug resistance was observed in two isolates, belonging to RT-126. Furthermore, RT-126 isolates were positive for tetracycline resistance determinants, confirming that tetracycline resistance is widespread among ST11 isolates from cattle. The administration of penicillins increased the risk of C. difficile in calves: this, together with the recovery of multi-resistant strains, strongly suggests the need for minimising antibiotic misuse on cattle farms.

scholarly journals Biofilm Formation in Multi-Drug Resistant Staphylococcus Aureus Isolates from Hospitalized Patients

2015 ◽  
Vol 1 (2) ◽  
pp. 27-31 ◽  
Author(s):  
Abdolmajid Ghasemian ◽  
Shahin Najar Peerayeh ◽  
Bita Bakhshi ◽  
Mohsen Mirzaee
Keyword(s):  
Staphylococcus Aureus ◽  
Biofilm Formation ◽  
Multiple Drug Resistance ◽  
Sccmec Type ◽  
Multidrug Resistant ◽  
Hospitalized Patients ◽  
The Body ◽  
Multiple Drug ◽  
Accessory Gene ◽  
Antibiotic Susceptibility Test

Background: The biofilm production is an important phenomenon by bacteria such as Staphylococcus aureus that contribute to the multiple drug resistance. Moreover, biofilm formation by multidrug-resistant Staphylococcus aureus causes evading from immune responses. Objective: The aim of this study was to detect biofilm formation and presence of several related genes among multidrug-resistant (MDR) isolates of Staphylococcus aureus. Methods: This cross sectional study was conducted at a hospital in Tehran, Iran from July 2012 to January 2013. Patients admitted with the infections of the different sites of the body were selected as study population. Staphylococcus aureus isolates were collected from hospitalized patients and identified by conventional diagnostic tests. The multidrug-resistant MRSA isolates were detected by antibiotic susceptibility test. The phenotypic biofilm formation was detected by micro-titre tissue plate assay. The polymerase chain reaction (PCR) was performed to detect the mecA, Staphylococcal Cassette Chromosome mec (SCCmec) types, accessory gene regulatory (agr) genes, the icaADBC and several genes encoding staphylococcal surface proteins including clfAB, fnbAB, fib, eno, can, ebps and bbp genes with specific primers. Results: A total number of 209 Staphylococcus aureus were isolated of which 64 (30.6%) isolates were methicillin-resistant; among which 36(56.2%) isolates were MDR. These isolates were resistant to amoxicillin, tetracycline, ciprofloxacin, gentamicin, erythromycin and trimethoprim-sulfamethoxazole. All the isolates were susceptible to vancomycin and linezolid. All the MDR-MRSA harbored SCCmec type III. All the MDR- MRSA isolates were strong biofilm producers in the phenotypic test. Conclusions: Multidrug-resistant MRSA isolates produced biofilm strongly and the majority of these isolates harbored most of biofilm related genes.Bangladesh Journal of Infectious Diseases 2014;1(2):27-31

scholarly journals Tetracycline Resistance in Group A Streptococci: Emergence on a Global Scale and Influence on Multiple-Drug Resistance

2007 ◽  
Vol 51 (5) ◽  
pp. 1865-1868 ◽  
Author(s):  
Vanessa Ayer ◽  
Wezenet Tewodros ◽  
Anand Manoharan ◽  
Sini Skariah ◽  
Feng Luo ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Multiple Drug Resistance ◽  
Tetracycline Resistance ◽  
Global Scale ◽  
Multiple Drug ◽  
Group A Streptococci ◽  
Group A

ABSTRACT A global sample of group A streptococci (GAS) revealed ≥80 separate acquisitions of tetracycline resistance. Of 244 clones, 38 and 25% displayed resistance to tetracycline and erythromycin, respectively; a relatively high proportion (15%) were resistant to both classes of drugs. tet(M) displayed a highly significant association with erm(B).

scholarly journals PHARMACOKINETICS OF INH AND PZA IN MDR-TB: A REVIEW

2019 ◽  
Vol 7 (5) ◽  
Author(s):  
S. Ramya ◽  
S. Shanmugam
Keyword(s):  
Drug Resistance ◽  
Time Course ◽  
Multiple Drug Resistance ◽  
Treatment Compliance ◽  
The Body ◽  
Multiple Drug ◽  
Second Line ◽  
Affected Patient ◽  
First Line ◽  
Mdr Tb

Tuberculosis remains a leading cause of morbidity and mortality in developing countries, including india. Isoniazid and pyrazinamide are powerful drugs administered as the First line and second line Anti-TB drugs in Tuberculosis affected patient. It plays a key role in shortening the TB therapy. Isoniazid (INH), and pyrazinamide (PZA) are the main drugs for the treatment of tuberculosis (TB). Mycobacterium tuberculosis is responsible for causing tuberculosis can acquire multiple drug resistance (MDR) by not responding to the most powerful anti-TB agents. The complications of drug resistance in TB elevates the some of the risk factors like inadequate treatment compliance, noncompliance of the patients to the treatment. Pharmacokinetics provides a basic time course of drugs and their effects in the body. These pharmacokinetic processes referred to as ADME. Key words Isoniazid, Pyrazinamide, MDR, ADME, TB

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