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21.
Drift of tetM determinant in urogenital microbiocenosis containing mycoplasmas during treatment with a tetracycline antibiotic 总被引:1,自引:0,他引:1
Taraskina AE Savicheva AM Akopian TA Soroka AE Momynaliev KT Govorun VM 《Bulletin of experimental biology and medicine》2002,134(1):60-63
We studied the correlation between genetic transfer of tetM determinant in Tn916 conjugative transposon by urogenital mycoplasmas (Mycoplasma hominis and Ureaplasma urealyticum) and changes in the bacterial repertoire during treatment with a tetracycline antibiotic. Basic conditions favoring the nonspecific transfer of tetM determinant into mollicute cells are determined and the allele polymorphism of tetM determinant in clinical strains of M. hominis and U. urealyticum is evaluated. The structure of tetM gene in clinical mycoplasma and ureaplasma strains is characterized by a peculiar mosaic pattern and differs from all previously described alleles of this gene. The results suggest that tetracycline resistance in mollicutes is determined by mechanisms alternative to genetic transfer of tetM determinant. 相似文献
22.
Matthew W. Ruble Deborah H. Gilbert Stephen H. Zinner 《Clinical microbiology and infection》1996,1(3):183-189
Objective: To determine the combined in-vitro effects of azithromycin plus the fluoroquinolone ofloxacin or lomefloxacin against gram-positive and gram-negative bacteria.
Methods: Fractional inhibitory (FIC) and fractional bactericidal concentration indices of azithromycin and the fluoroquinolone were determined using a microtiter-checkerboard method. Clinical isolates of Staphylococcus aureus, Streptococcus pneumoniae, Neisseria gonorrhoeae, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Pseudomonas cepacia, Haemophilus influenzae, Xanthomonas maltophilia and Acinetobacter calcoaceticus were studied. Fourteen strains of S. aureus were also studied in time-kill curves with azithromycin (4 mg/L), lomefloxacin (6 mg/L) and the two in combination.
Results: No synergism or antagonism was found in inhibitory assays. However, bactericidal assays revealed antagonism with some strains of S. aureus, S. pneumoniae, X. maltophilia, A. calcoaceticus, P. aeruginosa, P. cepacia, K. pneumoniae and E. coli. Kill-curve results with 14 strains of S. aureus showed no antagonism with four strains of methicillin-resistant S. aureus (MRSA), and antagonism with one strain of MRSA and seven methicillin-susceptible S. aureus (MSSA).
Conclusions: In-vitro exposure to combinations of azithromycin and a fluoroquinolone does not produce a synergistic effect. Antagonism was found in bactericidal assays against some gram-negative bacteria and MSSA; caution is therefore recommended in the use of macrolides and quinolones against these organisms. 相似文献
Methods: Fractional inhibitory (FIC) and fractional bactericidal concentration indices of azithromycin and the fluoroquinolone were determined using a microtiter-checkerboard method. Clinical isolates of Staphylococcus aureus, Streptococcus pneumoniae, Neisseria gonorrhoeae, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Pseudomonas cepacia, Haemophilus influenzae, Xanthomonas maltophilia and Acinetobacter calcoaceticus were studied. Fourteen strains of S. aureus were also studied in time-kill curves with azithromycin (4 mg/L), lomefloxacin (6 mg/L) and the two in combination.
Results: No synergism or antagonism was found in inhibitory assays. However, bactericidal assays revealed antagonism with some strains of S. aureus, S. pneumoniae, X. maltophilia, A. calcoaceticus, P. aeruginosa, P. cepacia, K. pneumoniae and E. coli. Kill-curve results with 14 strains of S. aureus showed no antagonism with four strains of methicillin-resistant S. aureus (MRSA), and antagonism with one strain of MRSA and seven methicillin-susceptible S. aureus (MSSA).
Conclusions: In-vitro exposure to combinations of azithromycin and a fluoroquinolone does not produce a synergistic effect. Antagonism was found in bactericidal assays against some gram-negative bacteria and MSSA; caution is therefore recommended in the use of macrolides and quinolones against these organisms. 相似文献
23.
目的探讨抗生素不同用药方案对乳癌术后手术部位感染的预防效果和成本的影响。方法506例乳腺癌改良根治手术患者随机分为观察组(n=253)和对照组(n=253)。观察组术前半小时静脉滴注头孢曲松2.0g;对照组术后3d每天静脉滴注头孢曲松2.0g。观察和记录术后患者手术部位感染情况并计算感染有关的医疗成本。结果术后感染发生率观察组和对照组分别为1.19%(3/252)和1.58%(4/253),其中手术部位感染共6例(1.19%),观察组和对照组各3例(1.19%),差异无统计学意义(P>0.05);对照组呼吸道感染1例。预防和治疗术后感染的直接医疗费用观察组为(163±78)元,对照组为(388±134)元,差异有统计学意义(P<0.05)。结论成本-效果分析表明,术前单次头孢曲松在预防手术部位感染方面与对照组等效,且医疗费用显著降低,具有更高的性价比。 相似文献
24.
Treatment of acute post-surgical infection of joint arthroplasty 总被引:3,自引:0,他引:3
A. Soriano S. García G. Bori M. Almela X. Gallart F. Macule J. Sierra J. A. Martínez S. Suso J. Mensa 《Clinical microbiology and infection》2006,12(9):930-933
The best antibiotic regimen for acute prosthetic joint infection, treated without removal of the implant, has not been well-defined. This study describes the use of a protocol based on oral rifampicin combinations to treat 47 cases that were followed prospectively for a 2-year period. The regimen used most commonly was levofloxacin 500 mg/24 h plus rifampicin 600 mg/24 h for a mean duration of 2.7 ± 1 months. The cure rate was 76.9%, and the only independent risk-factor associated with treatment failure was infection caused by methicillin-resistant Staphylococcus aureus or Enterococcus spp. (OR 17.6, p 0.003). Overall, the results suggested that use of oral antibiotics, including rifampicin, for 2–3 months was a good treatment option. 相似文献
25.
Salim R Ben-Shlomo I Colodner R Keness Y Shalev E 《Human reproduction (Oxford, England)》2002,17(2):337-340
BACKGROUND: Overgrowth of bacteria in the birth canal is associated with an increased risk of late miscarriage, preterm labour, post-partum endometritis and low birthweight. Conception rates in assisted reproduction treatments (ART) remain frustratingly low. We examined whether the nature of bacterial flora, found in the uterine cervical canal at embryo transfer, is associated with the rate of conception in ART. METHODS: We sampled for bacteriological culture the cervical canal of 204 patients who underwent embryo transfer. Of these, 139 (68%) were of fresh embryos, following recent vaginal oocyte retrieval and prophylactic antibiotic therapy, and 65 (32%) of frozen-thawed embryos, without any vaginal intervention in the preceding days. Bacteriological work-up included identification, colony count and antibiotic susceptibility profile. Conception was correlated with bacterial type and colony count. RESULTS: In 75 patients (36.8%) sterile cervical cultures or lactobacillus were recorded. Of these 75 patients, 23 (30.7%) conceived, whereas among the 129 in whom any pathogenic micro-organism was recovered only 21 (16.3%) conceived (P = 0.002). No difference in colonization was found between women who underwent frozen-thawed versus fresh embryo transfer (57 and 67% respectively). Any Gram-negative colonization was associated with no conception. All Gram-positive, and 90% of the Gram-negative bacteria, were sensitive to augmentin. CONCLUSIONS: Failure to conceive in ART is significantly associated with bacterial colonization of the uterine cervix. 相似文献
26.
Ching-Yi Cho Yi-Hsuan Tang Yu-Hsuan Chen Szu-Yao Wang Yi-Hsin Yang Ting-Hao Wang Chang-Ching Yeh Keh-Gong Wu Mei-Jy Jeng 《Journal of microbiology, immunology, and infection》2019,52(2):265-272
Background
Group B Streptococcus (GBS) infection is one of the major causes of neonatal morbidity and mortality. Universal GBS screening with intrapartum antibiotic prophylaxis (IAP) in pregnant women were initiated in 2012 in Taiwan. This study aimed to analyze the most recent maternal GBS colonization rate and the changes in neonatal GBS infection rate from 2011 to 2016.Methods
All pregnant women and their live born neonates between January 2011 and June 2016 were retrospectively reviewed. Whether GBS screening was done, screening results, presence of risk factors, the use of antibiotics, and neonatal outcome were analyzed. In addition, hospitalized neonates diagnosed with GBS infections were retrieved for comparison of early onset disease (EOD) (<7 days) and late onset disease (LOD) (≥7 days).Results
A total of 9535 women delivered babies during the study period. The maternal GBS screening rate was 71.0% and the colonization rate was 22.6%. The overall neonatal invasive GBS infection rate was 0.81 per 1000 live births and the vertical transmission rate was 1.2%. After 2012, the invasive neonatal GBS infection rate declined from 1.1–1.6‰ to 0.6–0.7‰ in 2014 and thereafter, the GBS EOD incidence rate declined from 2.8‰ to 0.0–0.6‰, but the LOD incidence rate remained approximately 0.7‰. Infants with EOD had strong association with obstetric risk factors.Conclusions
Taiwan's universal GBS screening with IAP program reduced the incidence rate of neonatal GBS EOD to be lower than 1‰ after 2012. Pediatricians still should pay attention to infants with GBS LOD since its incidence rate remained unchanged. 相似文献27.
Summary The interaction between the main components of the new glycopeptide antibiotic teicoplanin, A2–2, A2–3, A2–4, A2–5 and A3–1, and human serum albumin has been studied in vitro by equilibrium dialysis (pH 7.4, 37°C).From Scatchard analysis of the data, the calculated association constants (Ka) were: A2–2, 2.47×104, A2–3, 2.86×104, A2–4, 2.95×104 and A2–5, 3.87×104 mol·l–1. The number of binding sites per albumin molecule ranged between 1.23 to 1.31. A3–1 had a lower affinity with a Ka of about 5×103 mol·l–1.Extrapolated to the in vivo situation, the data suggested that about 90–95% of A2 components will be bound to serum albumin, and about 68–72% of A3–1.The in vitro findings were confirmed by a pharmacokinetic study in volunteers given [14C] teicoplanin i.v., in whom the fraction of teicoplanin bound to serum protein ranged between 87.6 and 90.8%. 相似文献
28.
Perioperative Cefamandolprophylaxe bei aortocoronaren Bypass-Operationen Serumkonzentrationsverlauf während der extrakorporalen Zirkulation 总被引:1,自引:0,他引:1
W. Klepetko A. Georgopoulos W. Graninger J. Miholic W. Sandtner 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1984,362(4):237-243
Zusammenfassung Eine perioperative antibiotische Kurzprophylaxe mit 2 g Cefamandol intravenös bei Narkoseeinleitung wurde bei 12 Patienten während coronarchirurgischer Eingriffe unter Verwendung der Herz-Lungen-Maschine durchgeführt. Bei Beginn der extrakorporalen Zirkulation (= EKZ) kam es infolge Hämodilution zu einem Absinken der Serumkonzentrationen von 110,96 ± 40,29 mcg/ml auf 70,89 ± 34,65 g/ml innerhalb von 10 min. Im weiteren Verlauf der EKZ war der Abfall der Serumspiegel gleich schnell wie davor und danach. Nach 240 min fanden sich noch Serumspiegel von 16,80 ± 9,32 g/ml. Als Ursache für das Versagen einer antibiotischen Prophylaxe kommt bei einer Operationsdauer von mehr als 4 h das Absinken der Serumspiegel unter die minimale Hemmkonzentration der entsprechenden Keime in Frage.
Perioperative cefamandole prophylaxis in aortocoronary bypass operations: Course of serum concentration during extracorporeal circulation
Summary Antibiotic prophylaxis with 2 g Cefamandole at induction of anaesthesia was performed in 12 male patients undergoing aortocoronary bypass surgery. Caused by hemodilution, there was a marked decrease of serum concentration at the beginning of extracorporeal circulation, from 110.96 ± 40.29 mcg/ml to 70.89 ± 34.65 mcg/ml within 10 min. During extracorporeal circulation, elimination was as fast as before and after perfusion. 240 min after application, mean serum concentrations of 16.80 ± 9.32 mcg/ml were measured. Failure of antibiotic prophylaxis in operations exceeding 4 h might be due to unadaequate antibiotic concentrations, beyond the minimal inhibitory concentration for the pathogens, reported to cause infections after cardiac operations.相似文献
29.
Hashaam Akhtar Samar Akhtar Fazal-Ul Rahman Maham Afridi Sundas Khalid Sabahat Ali Nasim Akhtar Yousef S Khader Hamaad Ahmad Muhammad Mujeeb Khan 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundSince the first reports of COVID-19 infection, the foremost requirement has been to identify a treatment regimen that not only fights the causative agent but also controls the associated complications of the infection. Due to the time-consuming process of drug discovery, physicians have used readily available drugs and therapies for treatment of infections to minimize the death toll.ObjectiveThe aim of this study is to provide a snapshot analysis of the major drugs used in a cohort of 1562 Pakistani patients during the period from May to July 2020, when the first wave of COVID-19 peaked in Pakistan.MethodsA retrospective observational study was performed to provide an overview of the major drugs used in a cohort of 1562 patients with COVID-19 admitted to the four major tertiary-care hospitals in the Rawalpindi-Islamabad region of Pakistan during the peak of the first wave of COVID-19 in the country (May-July 2020).ResultsAntibiotics were the most common choice out of all the therapies employed, and they were used as first line of treatment for COVID-19. Azithromycin was the most prescribed drug for treatment. No monthly trend was observed in the choice of antibiotics, and these drugs appeared to be a random but favored choice throughout the months of the study. It was also noted that even antibiotics used for multidrug resistant infections were prescribed irrespective of the severity or progression of the infection. The results of the analysis are alarming, as this approach may lead to antibiotic resistance and complications in immunocompromised patients with COVID-19. A total of 1562 patients (1064 male, 68.1%, and 498 female, 31.9%) with a mean age of 47.35 years (SD 17.03) were included in the study. The highest frequency of patient hospitalizations occurred in June (846/1562, 54.2%).ConclusionsGuidelines for a targeted treatment regime are needed to control related complications and to limit the misuse of antibiotics in the management of COVID-19. 相似文献
30.
《Value in health》2021,24(12):1828-1834
Antimicrobial resistance is a serious challenge to the success and sustainability of our healthcare systems. There has been increasing policy attention given to antimicrobial resistance in the last few years, and increased amounts of funding have been channeled into funding for research and development of antimicrobial agents. Nevertheless, manufacturers doubt whether there will be a market for new antimicrobial technologies sufficient to enable them to recoup their investment. Health technology assessment (HTA) has a critical role in creating confidence that if valuable technologies can be developed they will be reimbursed at a level that captures their true value. We identify 3 deficiencies of current HTA processes for appraising antimicrobial agents: a methods-centric approach rather than problem-centric approach for dealing with new challenges, a lack of tools for thinking about changing patterns of infection, and the absence of an approach to epidemiological risks. We argue that, to play their role more effectively, HTA agencies need to broaden their methodological tool kit, design and communicate their analysis to a wider set of users, and incorporate long-term policy goals, such as containing resistance, as part of their evaluation criteria alongside immediate health gains. 相似文献