Biomedical subjects

C E Nord

Publications and source records attributed to C E Nord.

At least 19 recordsLinked to original sources

PubMed2007

Emergence of VanD-type vancomycin-resistant Enterococcus faecium in Stockholm, Sweden.

A vancomycin-resistant Enterococcus faecium isolate from the urine of a liver transplant patient in Stockholm was found to contain a vanD gene. The sequence of the vanD PCR product shared 100% identity with the vanD5 allele. The isolate was resistant to a relatively high level of vancomycin (128 mg/L) and a low level of teicoplanin (4 mg/L). This is the first VanD-type vancomycin-resistant E. faecium isolate reported in Sweden. The emergence of this strain reinforces the necessity of infection control efforts to interrupt the spread of these organisms.

Alleles↗

PubMed2006

Examination of cfiA-mediated carbapenem resistance in Bacteroides fragilis strains from a European antibiotic susceptibility survey.

Of 1284 Bacteroides strains collected in Europe in 2000 for antibiotic susceptibility surveillance, 65 isolates displayed imipenem minimum inhibitory concentrations (MICs) > or =1 mg/L and were chosen for a thorough analysis of their resistance mechanism. Twenty-five of the isolates were positive for the cfiA carbapenem resistance gene. The resistance rates were 0.8% and 1.3% for imipenem and meropenem, respectively. In six of the strains, insertion sequence (IS) elements (IS613, IS614B, IS1186 and IS1187) activated the cfiA gene. However, other strains displayed at least elevated carbapenem MICs or were carbapenem resistant and produced measurable carbapenemase activities but did not harbour IS elements in the region upstream of the cfiA gene. The major determinant of carbapenem resistance in Bacteroides fragilis is production of CfiA metallo-beta-lactamase via activation of the cfiA gene by IS elements (higher level resistance) or by activation of its putative own promoter.

Anti-Bacterial Agents↗

PubMed2005

Probiotics and gastrointestinal diseases.

There is increasing evidence indicating health benefits by consumption of foods containing microorganisms, i.e. probiotics. A number of clinical trials have been performed to evaluate the effects in the prevention and treatment of gastrointestinal diseases caused by pathogenic microorganisms or by disturbances in the normal microflora. Gastrointestinal infections caused by Helicobacter pylori, traveller's diarrhoea, rotavirus diarrhoea, antibiotic-associated diarrhoea (AAD) and Clostridium difficile-induced diarrhoea are conditions that have been studied. There are also studies performed on the preventive effect of probiotics on radiation-induced diarrhoea and diarrhoea in tube-fed patients. Inflammatory bowel disease and irritable bowel syndrome, two idiopathic conditions where alterations in the normal microflora have been implicated as responsible for initiation, are two further areas where the use of probiotics has been regarded as promising. The results from clinical studies have not been conclusive in that the effects of probiotics have been strain-dependent and different study designs have been used. Treatment of acute diarrhoea in children and prevention of AAD are the two most justified areas for the application of probiotics.

Acute Disease↗

PubMed2005

European surveillance study on the antibiotic susceptibility of Propionibacterium acnes.

Propionibacterium acnes strains are recovered from infections linked to surgical procedures, foreign bodies and septicaemia. This study investigated the antibiotic susceptibility patterns of P. acnes isolates from different systemic infections and determined the genomic diversity among resistant P. acnes isolates with low-frequency restriction analysis of chromosomal DNA by pulsed-field gel electrophoresis (PFGE). In total, 304 P. acnes isolates from 13 laboratories in 13 European countries were tested against six antimicrobial agents by the NCCLS reference agar dilution method and the breakpoints recommended by the European Committee on Antimicrobial Susceptibility Testing. Blood isolates were encountered most frequently, followed by those from skin and soft tissue infections, and abdominal infections. Of the isolates examined, 2.6% were resistant to tetracycline, 15.1% to clindamycin, and 17.1% to erythromycin. No resistance was observed to linezolid, benzylpenicillin or vancomycin. There was considerable variation between countries in the proportion of resistant strains, ranging from 83% in Croatia and 60% in Italy to 0% in The Netherlands. Isolates from blood were predominant among the resistant isolates. Seventeen clones and 78 banding patterns were identified among the resistant isolates. It was concluded that antimicrobial resistance has now emerged among P. acnes isolates from systemic infections.

Anti-Bacterial Agents↗

PubMed2004

Impact of ketolides on resistance selection and ecologic effects during treatment for respiratory tract infections.

Ketolides are a new class of antibacterials that have been specifically developed for the treatment of community-acquired respiratory tract infections in an era of increasing resistance among major etiologic pathogens. These agents possess several unique structural features, including a 3-keto function and a large aromatic side chain, that confer not only a mode of action that differentiates them from the macrolide class but also a reduced potential to induce--or select for--resistant strains. Studies also suggest that ketolides such as telithromycin have a lower ecologic impact on the body's microflora than agents such as clarithromycin and amoxicillin-clavulanate, potentially reducing the risk of emergence of resistant strains and the spread of such resistance to pathogenic species. Therefore, available evidence suggests that ketolides may not only provide important new treatment options in an era of increasing resistance but may also contribute to reducing the pressure for development of further resistance. Clearly, further studies are required to confirm this low resistance potential once the ketolide agents become more widely used in routine practice.

Anti-Bacterial Agents↗

PubMed2004

Rapid and sensitive diagnosis of Toxoplasma gondii infections by PCR.

DNA was extracted with a modified Qiagen DNA Mini Kit method from 20 clinical samples and was amplified by PCR using specific primers for the T. gondii B1 gene. T. gondii was detected correctly in 18 of the 20 clinical samples in < 5 h, with a detection limit of two parasites/sample. The results were in good agreement with those obtained by a more complicated and time-consuming procedure involving two-step nested PCR and either liquid hybridisation or colorimetric detection using internal probes.

Amniotic Fluid↗

PubMed2004

Reduced susceptibility to penicillin of viridans group streptococci in the oral cavity of patients with haematological disease.

The occurrence of oral penicillin-resistant viridans group streptococci (VGS) was studied in 50 patients with either newly diagnosed acute leukaemia or autologous peripheral stem cell transplants. One patient was excluded because of Staphylococcus aureus growth in the stem cell harvest. VGS were isolated from the oral cavity of 48 of the remaining 49 patients. Of these 48 patients, 12 (25%) yielded VGS resistant (MIC > 2 mg/L) to penicillin. These 12 patients had a higher frequency of septicaemia (p 0.04) and more days of treatment with trimethoprim-sulphamethoxazole (p 0.04) than patients who harboured susceptible or intermediately resistant VGS (MIC 2 mg/L). There were no other statistically significant differences between the two groups. It is important to be aware of the high level of penicillin resistance in oral VGS in patients with haematological disease, and this parameter should be considered when selecting antibiotic therapy for cases of septicaemia caused by VGS in immunocompromised patients.

Adult↗

PubMed2004

In vitro activity of ABT-492 against anaerobic bacteria.

The purpose of the study was to determine the in vitro activity of ABT-492 compared with that of other antimicrobial agents against anaerobic bacteria. The activity of ABT-492 was investigated against 369 clinical isolates of anaerobic bacteria by the agar dilution method and was compared with that of moxifloxacin, piperacillin, cefoxitin, imipenem, clindamycin and metronidazole. ABT-492 and imipenem were the most active antimicrobial agents tested.

Anti-Bacterial Agents↗

PubMed2003

The micro-flora of the small bowel in health and disease.

The micro-flora of the proximal jejunum in healthy volunteers was compared with the micro-flora in patients with gastrointestinal symptoms suggestive of spontaneous bacterial overgrowth in the small intestine. Biopsies were taken distally to the ligament of Treitz with a Watson capsule. The samples were diluted and inoculated on selective and non-selective agar plates that were incubated aerobically and anaerobically. No major differences were found in the small jejunum micro-flora in healthy persons or in a heterogenous group of patients with gastrointestinal disorders. Oropharyngeal micro-organisms dominated the micro-flora in all subjects and colonic micro-organisms were found in low numbers in a few subjects from both groups. Streptococcus intermedius and Haemophilus parahaemolyticus were only found in the micro-flora of healthy subjects while Lactobacillus spp. was more frequently found in the samples from patients. Eight of 20 healthy subjects and five of 18 patients met the criterion of small intestinal overgrowth. Emerging evidence suggests that other factors are involved in the pathogenesis of the irritable bowel syndrome complex. There is a need for better understanding of the complicated interactions between the host and the endogenous micro-flora.

Journal Article↗

PubMed2003

Dientamoeba fragilis--a protozoal infection which may cause severe bowel distress.

A retrospective study of 87 patients diagnosed with the protozoan Dientamoeba fragilis was performed due to a recent increase in the number of patients diagnosed with this organism at the Unit of Clinical Parasitology, Huddinge University Hospital, Stockholm, Sweden. Medical records were reviewed. The highest incidence was found in pre-school boys, who also had the longest duration of symptoms, with a range of 1-630 weeks. A majority of the patients had symptoms of diarrhea, abdominal pain and flatus. The diarrhea varied from watery to loose, blood being reported only sporadically. Most patients had traveled outside Europe and had no other parasites in their stools. This study indicates potential pathologic properties in D. fragilis, and prospective studies are recommended.

Adolescent↗

PubMed2003

Will triclosan in toothpaste select for resistant oral streptococci?

The aims of the study were to determine the in vitro sensitivity of triclosan against viridans streptococci and the impact of triclosan on the normal oral microflora. Nine subjects used a triclosan-containing toothpaste for 2 weeks. Saliva samples were collected on days 0 and 14 and were analyzed quantitatively. The minimum inhibitory concentrations of triclosan and of several antimicrobial agents were determined for the streptococci isolated on days 0 and 14. No major changes occurred in the normal oral microflora during the study period. There were no differences in susceptibility between streptococcal strains collected at days 0 and 14 against triclosan or antimicrobial agents. Short-term use of triclosan has no major impact on normal oral microflora or on streptococcal susceptibility of antimicrobial agents. The effects of long-term use should be evaluated.

Anti-Infective Agents, Local↗

PubMed2003

Anaerobic bacteria commonly colonize the lower airways of intubated ICU patients.

OBJECTIVES: To investigate respiratory tract colonization by aerobic and anaerobic bacteria in mechanically ventilated patients. METHODS: Bacterial colonization of the stomach and the respiratory tract was qualitatively and quantitatively analyzed over time in 41 consecutive mechanically ventilated patients in a Swedish intensive care unit (ICU), with special emphasis on elucidation of the role of anaerobic bacteria in the lower respiratory tract. Samples were taken from the oropharynx, gastric juice, subglottic space and trachea within 24 h (median 14 h) of intubation, and then every third day until day 18 and every fifth day until day 33. RESULTS: The patients were often heavily colonized with microorganisms not considered to belong to a healthy normal oropharyngeal and gastric flora on admission to the ICU. A majority harbored enterococci, coagulase-negative staphylococci and Candida spp. in at least one site on day 1. Anaerobic bacteria, mainly peptostreptococci and Prevotella spp., were isolated from subglottic and/or tracheal secretions in 59% of the patients. Different routes of tracheal colonization for different groups of microorganisms were found. Primary or concomitant colonization of the oropharynx with staphylococci, enterococci, enterobacteria and Candida was often seen, while Pseudomonas spp., other non-fermenting Gram-negative rods and several anaerobic species often primarily colonized the trachea, indicating exogenous or direct gastrointestinal routes of colonization. CONCLUSIONS: Mechanically ventilated patients were heavily colonized in their lower airways by potential pathogenic microorganisms, including a high load of anaerobic bacteria. Different routes of colonization were shown for different species.

Bacteria, Anaerobic↗

PubMed2003

Antimicrobial susceptibility of Bacteroides fragilis group isolates in Europe.

OBJECTIVE: To evaluate the activity of old and newer antianaerobic drugs against clinical isolates of Bacteroides fragilis group strains from different parts of Europe. METHODS: Bacteroides fragilis group isolates from 37 laboratories in 19 countries were biochemically characterized. The MICs of seven antimicrobial agents were determined by the agar dilution method as recommended by the NCCLS. Production of beta-lactamase was detected by nitrocefin. RESULTS: There were 1284 B. fragilis group isolates included in the study. Abdominal infections and wounds were the most common sources of isolation and B. fragilis was the dominating species. Ninety-nine percent of the strains were resistant to ampicillin (breakpoint 2 mg/L), 6% to cefoxitin (64 mg/L), 15% to clindamycin (8 mg/L) and 9% to moxifloxacin (8 mg/L). Less than 1% were resistant to imipenem (16 mg/L), piperacillin-tazobactam (128 mg/L) and metronidazole (32 mg/L). Ninety-six percent of the isolates were beta-lactamase producers. CONCLUSIONS: Antimicrobial resistance among the B. fragilis group is increasing.

Anti-Bacterial Agents↗

PubMed2003

Effect of garenoxacin on eubacteria in the normal intestinal microflora when administered concomitantly with digoxin.

Garenoxacin is a new des-F(6)-quinolone with a broad antimicrobial spectrum. It has been reported that antibiotics may raise digoxin concentrations in the plasma of patients who are taking these agents concurrently, possibly due to the effect on the digoxin-metabolizing intestinal microflora. Sixteen healthy subjects were given a loading dose of digoxin (0.25 mg orally, q 6 h) on Day 1 followed by once-daily doses of 0.25 mg on Days 2 through 14. The subjects also received garenoxacin 600 mg orally, q 24 h, on Days 8 through 14. The number of enterococci, bacilli, corynebacteria, enterobacteria, bifidobacteria, lactobacilli, clostridia and bacteroides decreased whereas the number of eubacteria increased in the intestinal microflora. Eubacterium lentum strains increased during the administration of garenoxacin and returned towards normal levels within 14 days after the last dose of garenoxacin. The fecal concentrations of garenoxacin varied between 14.0-310.0 mg/kg. The minimum inhibitory concentrations of garenoxacin against the isolated E. lentum strains were >64 mg/L. There was no degradation of digoxin by the E. lentum strains.

Administration, Oral↗

PubMed2002

The fecal microflora of 1-3-month-old infants during treatment with eight oral antibiotics.

We examined the fecal microflora of 1-3-month-old infants during treatment with phenoxymethylpenicillin, amoxycillin, pivampicillin, cefaclor, cefadroxil, loracarbef, erythromycin or cotrimoxazole. Escherichia coli increased during treatment with penicillins or cephalosporins, but was not affected by erythromycin or cotrimoxazole. Other enterobacteria were acquired or increased during treatment with all agents except cotrimoxazole. Enterococci persisted or increased during phenoxymethylpenicillin, cephalosporin or cotrimoxazole treatment, whereas erythromycin and the other penicillins suppressed them. Bacteroides, bifidobacteria and lactobacilli were suppressed to undetectable levels in most infants during treatment with all agents, except phenoxymethylpenicillin and loracarbef.

Bacterial Infections↗

PubMed2002

The place of probiotics in human intestinal infections.

A number of studies have been carried out on the effect of several probiotic species on treatment and prevention of intestinal infections. The most commonly used microorganisms are lactic-acid producing bacteria such as lactobacilli and bifidobacteria belonging to the human normal microflora. In vitro and animal studies have shown that probiotic microorganisms interfere with the colonisation of Helicobacter pylori and of enteropathogenic microorganisms. In humans the significance is more uncertain. Clinically significant benefits of probiotics have been demonstrated in the treatment of rotavirus induced diarrhoea and of Saccharomyces boulardii in the prevention of antibiotic-associated diarrhoea (AAD). In patients suffering from inflammatory bowel disease, several probiotic strains have been shown to be as effective as traditional medication in preventing relapses. Standardised and well performed studies are needed to elucidate further the mechanisms of action and the clinical significance of probiotics.

Digestive System↗

PubMed2002

Ecological impact of the des-F(6)-quinolone, BMS-284756, on the normal intestinal microflora.

OBJECTIVE: BMS-284756 (T-3811ME) is a novel des-F(6)-quinolone effective against a broad spectrum of aerobic and anaerobic pathogens. The aim of this study was to investigate the ecological effect of BMS-284756 on the intestinal microflora. METHODS: Forty healthy subjects participated in the trial. Eight subjects were assigned to each of five dose panels (100, 200, 400, 800 and 1200 mg BMS-284756) and received daily oral dosing with either BMS-284756 (n = 6) or placebo (n = 2) for 14 days. Fecal samples were collected before (days -2 and -1), during (days 7 and 14), and after (days 21, 28, and 45) completion of the administration period. RESULTS: In subjects receiving 100 or 200 mg BMS-284756, no significant changes in the intestinal aerobic and anaerobic microflora occurred. The number of enterococci, bacilli, corynebacteria, bifidobacteria, lactobacilli, clostridia and bacteroides decreased in subjects receiving 400 or 800 mg BMS-284756, whereas the number of eubacteria increased. Subjects who received 1200 mg BMS-284756 had significant changes in the microflora: enterococci, bacilli, corynebacteria, enterobacteria, bifidobacteria, lactobacilli, clostridia and bacteroides were suppressed, whereas eubacteria and yeasts were increased. Regardless of dose, the microflora returned to normal levels at day 28 (2 weeks after the administration of BMS-284756 was discontinued). Fecal concentrations of BMS-284756 increased with the higher doses, from 35.7 mg/kg (100 mg) to 262.8 mg/kg (1200 mg). These ecological findings should be considered if 800- or 1200-mg doses of BMS-284756 are to be used for longer periods than 14 days. CONCLUSION: The ecological impact of BMS-284756 is selective, with results similar to those described for other quinolones.

Administration, Oral↗

PubMed2002

Effects of lactic acid bacteria on the uptake and distribution of the food mutagen Trp-P-2 in mice.

BACKGROUND: Lactic acid bacteria have been reported to have antimutagenic and anticarcinogenic properties in vivo and in vitro. Lactobacillus acidophilus and Bifidobacterium longum have earlier been shown to bind the food mutagen Trp-P-2 in vitro. METHODS: The influence of oral supplementation with L. acidophilus NCFB 1748 and B. longum BB 536 on the uptake and distribution of 14C-labelled Trp-P-2 in several mouse tissues was quantified by liquid scintillation measurements and examined by tape section autoradiography (gives an unbiased qualitative registration of differences in overall tissue distribution) in the present investigation. Furthermore, the effect of 13-naphthoflavone (BNF), a cytochrome P4501A (CYP1A)-inducing agent, on the distribution of 14C-labelled Trp-P-2 was examined. RESULTS: After oral (6 mg/kg; 5 microCi) or iv (1.2 mg/kg; 1 microCi) administration of 14C-labelled Trp-P-2, high levels of radioactivity were observed in the bile, urine and contents of the gastrointestinal tract. Lower levels were present in the liver, lung, kidney, intestines, brown fat, submaxillary salivary gland and thymus. In mice supplemented with lactic acid bacteria there was a significantly decreased level (29%-73%) of radioactivity in the lung, thymus, liver, kidney, submaxillary salivary gland and small intestine as compared with controls. In mice pretreated with BNF, a low but distinct localization of radioactivity in the lung was observed, whereas no similar localization occurred in controls. CONCLUSIONS: The results suggest that (i) there is a decreased bioavailability of the Trp-P-2 in the majority of the tissues examined in bacteria supplemented mice and (ii) there is a low but distinct CYP1A-dependent activation of Trp-P-2 in the lung of BNF-treated mice.

Animals↗