With the emergence of drug resistant tuberculosis, it is very urgent to find novel anti-tuberculosis drugs, especially novel anti-drug-resistant tuberculosis drugs. Because of the slow growth and the need to work in a biosafty environment of Mycobacterium tuberculosis, the development of evaluation of drug effect is severely impeded. In order to solve these issues, non-pathogenic fast-growing Mycobacterium smegmatis is introduced as test organism. The inhA is one of a target of isoniazid (INH) overexpression or mutation of this gene in Mycobacterium tuberculosis conferring resistant to INH. A recombinant plasmid bearing inhA was constructed and electroporated into Mycobacterium smegmatis, using shuttle expression vector pMV261. Transformants were induced to express a protein of inhA, identified by SDS-PAGE. Results show that Mycobacterium smegmatis containing inhA plasmids exhibited 100-fold or greater increased resistance to INH, but it conferred no increased resistance to others first-line anti-tuberculosis drugs. Resazurin microtiter assay plate testing of Mycobacterium smegmatis susceptibility to drugs is a rapid, simple, and inexpensive method and could decrease color background of drugs by detecting fluorescence. It will be benefit for high-throughout screening of drugs of anti-isoniazid-resistant Mycobacteria.
Anti-Bacterial Agents ; pharmacology ; Antibiotics, Antitubercular ; pharmacology ; Antitubercular Agents ; pharmacology ; Bacterial Proteins ; genetics ; metabolism ; Drug Resistance, Bacterial ; Electroporation ; Ethambutol ; pharmacology ; Isoniazid ; pharmacology ; Microbial Sensitivity Tests ; Mycobacterium smegmatis ; drug effects ; genetics ; metabolism ; Oxidoreductases ; genetics ; metabolism ; Plasmids ; Rifampin ; pharmacology ; Streptomycin ; pharmacology

OBJECTIVES: This study aimed to understand the nationwide patterns of antibiotic prescription after tooth extraction in adult patients.MATERIALS AND METHODS: This study analyzed dental records from the National Health Insurance Service–National Sample Cohort (NHIS–NSC) database on 503,725 tooth extractions performed in adults (≥19 years) during 2011–2015. Patient sex, age, household income, systemic disease (diabetes mellitus and hypertension), type of dental institution, region of dental institution, year of prescription, and type of tooth extraction procedure were considered. The antibiotic prescription rate and broad-spectrum antibiotic prescription frequency were analyzed using chi-squared tests. Factors affecting the prescription of broad-spectrum antibiotics were evaluated using multivariate logistic regression analysis.RESULTS: The rate of antibiotic prescription after tooth extraction was 81.85%. Penicillin was most commonly prescribed (45.25%), followed by penicillin with beta-lactamase inhibitors (18.76%), metronidazole (12.29%), and second- to fourth-generation cephalosporins (11.52%). The proportion of broad-spectrum antibiotics used among all prescribed antibiotics was 45.88%.CONCLUSION: The findings of this study demonstrate that the rate of antibiotic prescription after tooth extraction is higher in Korea than in other countries. Furthermore, broad-spectrum antibiotics are used more frequently, which may indicate unnecessary drug prescription, an important contributor to antibiotic resistance.
Adult ; Anti-Bacterial Agents ; beta-Lactamase Inhibitors ; Cephalosporins ; Cohort Studies ; Dental Records ; Drug Prescriptions ; Drug Resistance, Microbial ; Family Characteristics ; Humans ; Korea ; Logistic Models ; Metronidazole ; National Health Programs ; Penicillins ; Prescriptions ; Tooth Extraction ; Tooth

Multidrug-resistant (MDR) bacterial infections, especially those caused by Gram-negative pathogens, have emerged to be one of the world's greatest health threats. However, not only have recent decades shown a steady decline in the number of approved antimicrobial agents but a disappointing discovery also void. The development of novel antibiotics to treat MDR Gram-negative bacteria has been stagnated over the last half century. Though few compounds have shown activities in vitro, in animal models or even in clinical studies, the global antibiotic pipeline is not encouraging. There are a plethora of unexpected challenges that may arise and cannot always be solved to cause promising drugs to fail. This review intends to summarize recent research and development activities to meet the inevitable challenge in restricting the proliferation of MDR Gram-negative bacteria, with focus on compounds that have entered into clinical development stage. In addition to new analogues of existing antibiotic molecules, attention is also directed to alternative strategies to develop antibacterial agents with novel mechanisms of action.
Aminoglycosides ; pharmacology ; therapeutic use ; Animals ; Anti-Bacterial Agents ; pharmacology ; therapeutic use ; Antibodies, Monoclonal ; pharmacology ; therapeutic use ; Drug Discovery ; Drug Resistance, Multiple, Bacterial ; Enzyme Inhibitors ; pharmacology ; therapeutic use ; Ferrous Compounds ; pharmacology ; therapeutic use ; Gram-Negative Bacteria ; drug effects ; Gram-Negative Bacterial Infections ; drug therapy ; Humans ; Peptides ; pharmacology ; therapeutic use ; Peptidomimetics ; pharmacology ; therapeutic use ; Tetracyclines ; pharmacology ; therapeutic use ; beta-Lactamase Inhibitors ; beta-Lactams ; pharmacology ; therapeutic use

INTRODUCTION: This study aimed to determine the in vitro susceptibility of standard isolates of common pathogens causing bacterial conjunctivitis to non-fluoroquinolone antimicrobial ophthalmic medications. METHODS: This is a single-blind experimental study which compared the in vitro susceptibility of Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas aeruginosa and Staphylococcus epidermidis to locally available non-fluoroquinolone ophthalmic medications, specifically chloramphenicol, tobramycin, fusidic acid, gentamicin sulfate, sulfacetamide and polymyxin-neomycin. Utilizing the disk diffusion method, zones of inhibition in millimeters for each bacterial isolate was recorded and tabulated. Kruskal-Wallis test was used to determine statistical differences. RESULTS: Both Staphylococci were sensitive to all antibiotics except sulfacetamide. Only chloramphenicol showed activity against all four isolates. Tobramycin showed the largest zone of inhibition against Pseudomonas aeruginosa. There was statistically significant difference in the median zone of inhibition in each antimicrobial medication against Staphylococcus aureus (p = 0.002) and Staphylococcus epidermidis (p < 0.001) with the largest mean zone of inhibition by fusidic acid of 34 and 38 millimeters, respectively. Streptococcus pneumoniae was least susceptible to antibiotics tested; only chloramphenicol and fusidic acid showed activity. There were also significant differences in the median zones of inhibition across the isolates. CONCLUSION The standard isolates are susceptible to at least one non-fluoroquinolone ophthalmic medication. The antibiotics tested showed differences in activity against the four isolates. The findings of this study may be used as a basis to review local practice patterns or/and initiate revisions in the guidelines for prescribing initial treatment of bacterial conjunctivitis.
Conjunctivitis, Bacterial ; Anti-Bacterial Agents

No abstract available.
Anti-Bacterial Agents ; Diarrhea*

138 cases with bacterial septicemia in Bach Mai Hospital were divided into two groups. The first group (n=51, 36.9%) was given single treatment (one antibiotic). The second group (n=87, 63.1%) was given combination treatment (two antibiotics). Due to the rate of cultured negative blood is high (about 70%), so the rate of initial treatment using antibiotic combination (63%) is higher than single antibiotic treatment (37%). Antibiotic groups used in combination treatment is aminosid antibiotics, in which amikacin is selected the most (27/37 cases, 72.9%). Third generation cephalosporin group makes the highest rate in single treatment (49%) as well as in combination treatment (58.7%). Quinolones, pefloxacin group used almost as initial method (single as well as in combination)
Anti-Bacterial Agents ; Therapeutics

Isolate, purify, and identify bacteria from probiotic supplement. Results: 5 strains of lactic bacteria were determined, including: Steptococus feacalis; Streptococcus lactic; Bifidobacterium bifidum; Lactobaccillus acidophilus; Lactobacillus casei. Study the sensitivity of these bacteria with antibiotics, results showed that these bacteria were resistant to many antibiotics, especially oral antibiotics. Conjugative trial between Streptoccocus feacalis, Streptococus lactic, Bifidobacterium bifidum, lactobacillus acidophilus casei and E.coli K12, and conjugative trial of lactic bacteria together showed negative results. Therefore, probiotic product contained many lactic bacteria can be used concomitant with some oral antibiotics to prevent or treat digestive disorders
Anti-Bacterial Agents ; Bacteria

Bifidobacterium bifidum has been used in foreign to treat antibiotics induced diarrhoea with many advantages compared to Bacillus subtilis. But in Vietnam, there are not like this. We have researched a basis to use this bacterium in a pharmaceutical product. We isolated, screened the optimal conditions to culture B. bifidum and built up the growth curve of it. An in vitro trial had been developed on rat and showed that B. bifidum had a good effect on treatment antibiotics induced diarrhoea.
Bifidobacterium ; Anti-Bacterial Agents

By bromation of isatin 5-bromoisatin (I) was obtained. On boiling (I) with 4% formaldehyde solution for short period of time, a compound was isolated which has been characterized as N-hydroxymethyl-5-bromoisatin (II). By condensation of I with various H2N-B compounds, 6 derivatives (III-VIII) were formed. The structures of the obtained products were characterized by IR spectroscopy (II was characterized by MS, 1H.NMR). The synthesized compounds were tested for biological activities such as antibacterial and antifungal. Among these, two compounds (I, II) showed an antibacterial activity on 8 strains of bacteria. Compound VI showed an antibacterial activity on 3 strains of bacteria. Compound VI showed an antibacterial activity on 3 strains of bacteria.
Bufotenin ; Anti-Bacterial Agents

To predict the potential therapeutic efficacy of combination of antibiotics, methods have been developed to quantitative their effects on bacterial growth in vitro. Two distinct different methods are used. The first methods for evaluating drug combinations involve quantitation on their rate of bactericidal action. The second employs serial twofold dilution of antibiotics in broth in osculated with a standard number of the test microorganism in a checkerboard fashion, so that antibiotic concentration in different proportion can be tested simultaneously. Laboratory trials have carried out on antimicrobe resistant S. anreus. We found that gentamicine combined penicillin or gentamycine combined cephalothin in more rapidly bactericidal effect than either drug alone, the result is termed synergism. On the contrary, antagonism in said to occur with penicillin combined chloramphenicol.
Anti-Bacterial Agents ; Staphylococcus