AIMTo investigate whether tazobctam has crystallization water.

METHODSIn order to establish a method for water content determination in tazobctam, many methods including Karl Fischer titration, weight loss on drying, TGA, DSC and X-ray diffraction experiment of an orthorhombic form were studied.

RESULTSThe water content of the same batch tazobactam determined by different mthods was different.

CONCLUSIONThe results showed that one mole tazobatam contains half mole water of crystallization and the strength of attraction between tazobatam molecule and water molecule is rather strong.

Crystallization ; Enzyme Inhibitors ; chemistry ; Molecular Conformation ; Molecular Structure ; Penicillanic Acid ; analogs & derivatives ; chemistry ; Water ; X-Ray Diffraction ; beta-Lactamase Inhibitors ; beta-Lactamases ; chemistry

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

OBJECTIVETo investigate the mechanism of drug resistance of carbapenems-resistant Acinetobacter baumannii (CRAB) in burn patients and the antimicrobial activity of a combination of drugs against this bacteria in vitro.

METHODSA total of 135 strains of Acinetobacter baumannii (AB) from wound excretion, sputum, and venous catheter wall of patients hospitalized in our department from January 2011 to July 2013 were collected individually. Drug resistance of 135 strains of AB to 12 antibiotics commonly-used in clinic was detected using K-B paper diffusion method. Among the CRAB strains, double-disk synergy test was used to screen metallo-β-lactamase (MBL)-producing strains, and the drug resistance rates between MBL-producing strains and non-MBL-producing strains were compared. Minimal inhibitory concentration (MIC), 50% MIC (MIC50), and 90% MIC (MIC90) of cefoperazone/sulbactam, imipenem, cefepime, ampicillin/sulbactam, and amikacin used alone against MBL-producing CRAB were determined by broth microdilution method. MIC, MIC50, and MIC90 of amikacin respectively combined with imipenem, cefoperazone/sulbactam, cefepime, or ampicillin/sulbactam against MBL-producing CRAB were determined by checkerboard method with diluted agar. Fractional inhibitory concentration (FIC) index was calculated to determine the antibacterial effect of each combination of two antibiotics. Synergy with FIC lower than or equal to 0.5, or additivity with FIC higher than 0.5 and lower than or equal to 1.0 was regarded as effective, and indifference with FIC higher than 1.0 and lower than or equal to 2.0 or antagonism with FIC higher than 2.0 was regarded as ineffective. The effective rate was calculated. Data were processed with Chi-square test.

RESULTSThe resistant rates of the 135 strains of AB to imipenem, meropenem, and ceftazidime were high, and those of piperacillin/tazobactam and ampicillin/sulbactam were low. A total of 120 strains of CRAB was screened, accounting for 88.89%, among which the MBL-producing strains accounted for 78.33% (94/120). The resistant rates of MBL-producing strains to piperacillin/tazobactam, imipenem, meropenem, piperacillin, and cefepime were respectively 59.5%, 87.2%, 93.5%, 87.0%, 86.0%, and they were significantly higher than those of non-MBL-producing strains (respectively 43.0%, 81.3%, 87.5%, 78.4%, 64.0%, with χ(2) values from 4.571 to 8.260, P < 0.05 or P < 0.01). Among the inhibition concentrations of each of the 5 antibiotics used alone against MBL-producing strains, MIC, MIC50, and MIC90 of ampicillin/sulbactam were the lowest, respectively 4.00, 16, 64 µg/mL, while those of cefepime were high, respectively 32.00, 128, 512 µg/mL. MIC, MIC50, and MIC90 of amikacin combined with each of the other 4 antibiotics were decreased from 50.00% to 98.44% as compared with that of single administration of each antibiotic. Among the 94 strains of MBL-producing CRAB, the synergic, additive, indifferent, and antagonistic effects were respectively observed in 40, 33, 6, and 15 strains applied with combination of amikacin and ampicillin/sulbactam; 42, 30, 5, 17 strains applied with combination of amikacin and cefoperazone/sulbactam; 38, 15, 19, 22 strains applied with combination of amikacin and cefepime; 34, 2, 37, 21 strains applied with combination of amikacin and imipenem, among which the antibacterial effective rates decreased successively, respectively 77.7%, 76.6%, 56.4%, and 38.3%. The former two rates were respectively significantly higher than the latter two rates (with χ(2) values from 8.618 to 29.889, P values below 0.01).

CONCLUSIONSProduction of MBL is the main mechanism of resistance of the CRAB isolated from burn patients hospitalized in our department against carbapenems in about 3 years. The antibacterial effects of amikacin combined with each of the former-mentioned 4 agents are better than those of each of the five antibiotics used singly, and the effects are particularly obvious when combining amikacin with compound agent containing enzyme inhibitors.

Acinetobacter Infections ; drug therapy ; microbiology ; Acinetobacter baumannii ; drug effects ; isolation & purification ; Ampicillin ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Carbapenems ; pharmacology ; Cephalosporins ; pharmacology ; Drug Resistance ; Humans ; In Vitro Techniques ; Microbial Sensitivity Tests ; Penicillanic Acid ; analogs & derivatives ; pharmacology ; Pharmaceutical Preparations ; Piperacillin ; pharmacology ; Sulbactam ; pharmacology ; Thienamycins ; pharmacology ; beta-Lactamase Inhibitors ; pharmacology

BACKGROUND/AIMS: The number of urinary tract infections (UTIs) caused by extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-EC) is increasing. In an outpatient setting, there are limited therapeutic options to treat ESBL-producing pathogens. We evaluated the outcomes of amikacin outpatient parenteral antibiotic therapy (OPAT) for UTIs caused by ESBL-EC in patients not pre-treated with carbapenem. METHODS: We retrospectively evaluated the outcomes of amikacin OPAT for UTIs caused by ESBL-EC. RESULTS: From November 2011 to October 2012, eight females, who could not be hospitalized for carbapenem treatment, were treated with amikacin OPAT for nine episodes of non-bacteremic ESBL-EC UTIs. Seven of the eight patients had one or more comorbidities. Of the nine UTI cases, three had symptomatic lower UTIs and six had non-bacteremic upper UTIs. In all of the cases, symptomatic and laboratory improvements were observed following amikacin OPAT. One patient showed a delayed relapse with bilateral microabscesses 3 weeks after treatment cessation; however, a clinical and microbiological cure was eventually reached. All of the patients were able to tolerate amikacin OPAT without any significant nephrotoxicity or ototoxicity. CONCLUSIONS: Amikacin OPAT represents a feasible therapeutic option for non-bacteremic UTIs caused by ESBL-EC in settings with limited resources.
Adult ; Aged ; Aged, 80 and over ; Ambulatory Care ; Amikacin/administration & dosage/adverse effects/*therapeutic use ; Drug Administration Schedule ; Escherichia coli/*drug effects/enzymology/isolation & purification ; Escherichia coli Infections/diagnosis/*drug therapy/microbiology/urine ; Humans ; Microbial Sensitivity Tests ; Middle Aged ; Recurrence ; Remission Induction ; Retrospective Studies ; Time Factors ; Treatment Outcome ; Urinalysis ; Urinary Tract Infections/diagnosis/*drug therapy/microbiology/urine ; Urine/microbiology ; beta-Lactamase Inhibitors/administration & dosage/adverse effects/*therapeutic use ; beta-Lactamases/*metabolism