Safety of Bifidobacterium breve, Bif195, employing a human exercise-induced intestinal permeability model: a randomised, double-blinded, placebo-controlled, parallel group trial.

We have previously shown that the probiotic Bifidobacterium breve strain Bif195 alleviates mucosal injury including ulcer formation in the upper intestine induced by non-steroid anti-inflammatory drugs (NSAIDs). Here, we report additional safety use of Bif195 in 126 healthy humans undergoing an exercise-induced intestinal permeability challenge in a double-blinded, placebo-controlled randomised 6-week intervention trial. Intestinal permeability was assessed by urinary lactulose/rhamnose (L/R) ratio. L/R ratio, plasma intestinal fatty acid binding protein (I-FABP) and gastrointestinal symptom rating scale (GSRS) questionnaire were measured resting and after a 1 h treadmill challenge, prior to and at the end of the intervention. To be able to compare the equivalence of resting state at baseline, of this cohort of well-trained subjects, to non-trained subjects, a cohort of 63 healthy and non-trained subjects (<2 h/week of endurance sports) was included. Study subjects (well-trained) were 35.7% women with a mean age and body mass index (in kg/m2) of 35.0 years and 24.8, respectively. There were no differences between the Bif195 and placebo groups in effects on L/R ratio, I-FABP and GSRS questionnaire score. In addition, there were no differences between Bif195 and placebo in number of adverse events and change in cytokines, liver or kidney biomarkers. The exercise model successfully induced intestinal permeability by statistically significantly increasing L/R ratio by ~100% (P<0.0001) and cytokines after the exercise challenge. No significant difference was found between well-trained and non-trained subjects in baseline resting L/R ratio. In conclusion, the reported cytoprotective effects of Bif195 are unlikely to be primarily related to small bowel permeability, and the safety of Bif195 in individuals with increased permeability is supported by the present data. ClinicalTrials.gov: NCT03027583.

Heat-resistant, extended-spectrum ß-lactamase-producing Klebsiella pneumoniae in endoscope-mediated outbreak.

BACKGROUND: We describe an outbreak with an extended-spectrum ß-lactamase-producing Klebsiella pneumoniae strain in an intensive care unit in a secondary care hospital in Norway. The outbreak source was a fibreoptic intubation endoscope in which the outbreak strain survived despite chemothermal disinfection in a decontaminator designated for such use. The genetic marker clpK, which increases microbial heat resistance, has previously been described in K. pneumoniae outbreak strains. AIM: To investigate the role of clpK in biofilm formation and heat-shock stability in the outbreak strain. METHODS: The outbreak investigation was done by review of clinical records, screening of patients and culture from intubation endoscopes and bronchoscopes. Amplified fragment length polymorphism was used to identify the outbreak strain. clpK detection was performed by polymerase chain reaction, followed by mutant construction and heat-shock assays. FINDINGS: Five patients and one intubation endoscope contained K. pneumoniae with the same amplified fragment length polymorphism pattern. The outbreak strain contained the clpK genetic marker, which rendered the strain its increased heat resistance. The survival rate of the strain grown as biofilm following heat treatment was also strongly dependent on clpK. CONCLUSION: Although clpK has been associated with clinical isolates of K. pneumoniae in earlier outbreaks, this is the first time that a ClpK-producing strain has been isolated from an environmental outbreak source. Heat resistance of certain K. pneumoniae strains may facilitate survival in biofilms on medical equipment and hence increase the potential of those strains to persist and disperse in the hospital environment.

Antibody development to Fusobacterium necrophorum in patients with peritonsillar abscess.

A polymicrobial mixture of aerobic and anaerobic bacteria is commonly recovered from peritonsillar abscess (PTA) aspirates. Previous studies have suggested a role for Fusobacterium necrophorum (FN) in the development of PTA. The purpose of the current study was to explore whether anti-FN antibodies were produced in patients with PTA. We developed a novel immunofluorescence-based method to measure anti-FN antibody levels in acute and convalescent sera from 15 patients with PTA and 47 patients with chronic tonsillar conditions (controls) undergoing acute or elective tonsillectomy, respectively. Bacterial cultures were performed on tonsillar cores and surfaces, pus aspirates, and blood. An increase in anti-FN antibody levels (of at least doubling of the previous level) was observed in 8 of 11 (73 %) PTA patients with FN-positive pus aspirate cultures (FN-positive patients). In contrast, the four FN-negative PTA patients did not have an increase in anti-FN antibody levels (p = 0.026). The change in anti-FN antibody levels in FN-positive PTA patients was also significantly greater than that for FN-positive electively tonsillectomized patients (p = 0.0014) and all electively tonsillectomized patients (p < 0.001). Our results validate FN as a significant and prevalent pathogen in PTA. This finding has implications for the diagnostic work-up of PTA and may also have implications for the treatment of acute tonsillitis.

Synthesis and anti-angiogenic effect of conjugates between serum albumin and non-steroidal anti-inflammatory drugs.

Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit tumor growth and angiogenesis. Covalent linkage of naproxen to human serum albumin (HSA) has been shown to target it efficiently to the liver and this may potentially be exploited for liver-selective inhibition of angiogenesis. With the aim of investigating the anti-angiogenic efficiency of NSAID-HSA conjugates in vitro, three NSAIDs, aspirin, ibuprofen, and naproxen were conjugated to HSA using different concentrations of their N-hydroxysuccinimide esters. Conjugation ratios from 10 to 50 were achieved and the conjugates retained a growth inhibitory effect on endothelial cells at or above the level of the non-conjugated NSAIDs in an in vitro angiogenesis assay.

Intracellular persistence of Escherichia coli in urinary bladders from mecillinam-treated mice.

OBJECTIVES: It has been suggested recently that intracellular bacteria surviving antibiotic treatment might serve as a reservoir for recurrent infection. The purpose of this study was to directly examine the location of Escherichia coli bacteria in the mouse bladder after treatment with mecillinam. METHODS: The bladders were studied by use of colony counts, in situ hybridization and electron microscopy. RESULTS: The bacterial counts in the bladder remained approximately 10(3-4) cfu/bladder even after mecillinam treatment had finished, and re-growth in the urine was observed. In the bladder epithelium from treated mice, bacteria cells were occasionally seen, presumably representing intracellularly located bacteria. CONCLUSIONS: This is the first in vivo study indicating that during mecillinam treatment E. coli cells can penetrate the mouse bladder epithelium and persist.

Development of a long-term ascending urinary tract infection mouse model for antibiotic treatment studies.

A model of ascending unobstructed urinary tract infection (UTI) in mice was developed to study the significance of the antibiotic concentration in urine, serum, and kidney tissue for efficacy of treatment of UTI in general and pyelonephritis in particular. Outbred Ssc-CF1 female mice were used throughout the study, and Escherichia coli was used as the pathogen. The virulence of 11 uropathogenic E. coli isolates and 1 nonpathogenic laboratory E. coli strain was examined. Strain C175-94 achieved the highest counts in the kidneys, and this strain was subsequently used as the infecting organism. The model gave reproducible bladder infections, i.e., bacteria were recovered from 22 of 23 control mice after 3 days, and histological examination of kidney tissue showed that of 14 infected kidneys, 7 (50%) showed major histological changes, whereas 3 of 36 uninfected kidneys showed major histological changes (P = 0.018). Once the model was established, the efficacies of different doses of cefuroxime and gentamicin, corresponding to active concentrations in urine only or in urine, serum, and kidney tissue simultaneously, were examined. All cefuroxime doses resulted in significantly lower counts in urine than control treatments, but the dose which produced concentrations of cefuroxime only in urine and not in serum or kidney tissue had no effect on kidney infection. Even low doses of gentamicin (0.05 mg/mouse) resulted in concentrations in renal tissue for prolonged times due to accumulation. All gentamicin doses had a significant effect (compared to the effect of the control treatment) on bacterial counts in urine and kidneys. The antibiotic effect on bacterial counts in bladders was negligible for unknown reasons. Use of the mouse UTI model is feasible for study of the effect of an antibiotic in the urinary system, although the missing antibacterial effect in the bladder needs further evaluation.

In vivo detection of Escherichia coli type 1 fimbrial expression and phase variation during experimental urinary tract infection.

Adhesion mediated by fimbriae is thought to play an important role in the pathogenesis of urinary tract infections (UTI) by Escherichia coli. The majority of clinical isolates of E. coli from UTI are able to express type 1 fimbriae. However, the importance of these fimbriae as a virulence factor has been controversial. To investigate the expression of type 1 fimbriae in vivo during UTI, mice were transurethrally infected with uropathogenic E. coli C175-94 and type 1 fimbrial expression was determined directly by two independent methods at 2 h, 1 d and 3 d after infection. By use of an assay combining in situ rRNA hybridization and immunofluorescence, all bacterial cells detected in urine, bladders and kidneys from mice sacrificed 1 and 3 d after onset of infection were found to express type 1 fimbriae. In contrast, the majority of cells in the suspension used for infection of mice and specimens from mice sacrificed 2 h after inoculation were found to be non-fimbriated. Similar results were obtained with a PCR assay revealing the orientation of the invertible promoter driving the transcription of type 1 fimbrial genes. Whilst the promoter in both ON and OFF positions could be amplified from the suspension used for infection and specimens from mice sacrificed 2 h after inoculation, at 1 and 3 d after onset of infection only the promoter in the ON orientation could be amplified. These results show that introduction of E. coli C175-94 into the mouse urinary tract leads to markedly enhanced expression of type 1 fimbriae.

Pathogenic adaptation of Escherichia coli by natural variation of the FimH adhesin.

Conventional wisdom regarding mechanisms of bacterial pathogenesis holds that pathogens arise by external acquisition of distinct virulence factors, whereas determinants shared by pathogens and commensals are considered to be functionally equivalent and have been ignored as genes that could become adapted specifically for virulence. It is shown here, however, that genetic variation in an originally commensal trait, the FimH lectin of type 1 fimbriae, can change the tropism of Escherichia coli, shifting it toward a urovirulent phenotype. Random point mutations in fimH genes that increase binding of the adhesin to mono-mannose residues, structures abundant in the oligosaccharide moieties of urothelial glycoproteins, confer increased virulence in the mouse urinary tract. These mutant FimH variants, however, are characterized by increased sensitivity to soluble inhibitors bathing the oropharyngeal mucosa, the physiological portal of E. coli. This functional trade-off seems to be detrimental for the intestinal ecology of the urovirulent E. coli. Thus, bacterial virulence can be increased by random functional mutations in a commensal trait that are adaptive for a pathologic environment, even at the cost of reduced physiological fitness in the nonpathologic habitat.

Influence of frequency of previous pregnancies on the prevalence of thyroid nodules in women without clinical evidence of thyroid disease.

In a region with insufficient alimentary iodine supply (Kiel, Northern Germany) the prevalence of thyroid nodules was studied by means of ultrasonography in 212 healthy women (36-50 years old) in four groups of 53 women each with 0, 1, 2, and 3-5 previous pregnancies. Goiters were found in 28.3% (15 of 53) of the women without children and in 28.9% (46 of 159) of the women with children. There was no significant increase of goiter prevalence according to the number of pregnancies. We detected thyroid nodules in 21.2% (45 of 212). Only 9.4% (5 of 53) of the women without previous pregnancies had thyroid nodules, but 25.1% (40 of 159) of the women with pregnancies in the past had nodules, the difference being statistically significant (p < 0.05). We observed nodules in 11 of 53 women with 1 child (20.7%), in 11 of 53 women with 2 children (20.7%), and in 18 of 53 women with 3-5 previous pregnancies (33.9%). We propose that, in regions with borderline or insufficient alimentary iodine supply, accentuated iodine deficiency during pregnancies due to increase of iodine requirement is a probable cause for the higher prevalence of thyroid nodules in women with previous pregnancies.

[The effect of earlier pregnancies on the prevalence of goiter and nodules in thyroid-healthy women]. / Einfluss früherer Schwangerschaften auf Struma- und Knotenhäufigkeit bei schilddrüsengesunden Frauen.

Ultrasound scans of the thyroid were performed in 106 women of mean age 41.9 (36-50) years, 53 with and 53 without a history of previous pregnancy, with the object of ascertaining the prevalence of goitre and thyroid nodules. Goitres (defined as a thyroid volume exceeding 18 ml) were found in 22 of the women with previous pregnancies (41.5%). Thyroid nodules were found in 23 of the 106 women (21.6%). Whereas only five of the 53 women without previous pregnancies (9.4%) had thyroid nodules, they were noted in 18 of the 53 women who had had children (33.9%), the difference being statistically significant (P less than 0.05). Thyroid cysts were found in 12 of the 106 women (11.3%), though there was no significant difference between the two groups. Thyroid calcification was noted in only one woman. The results highlight the consequences of iodine deficiency in a region where iodine intake is inadequate (Kiel) and show that the deficiency is accentuated during pregnancy.

[Thyroid gland volumes and the incidence of focal changes in euthyroid men and women in various age groups]. / Schilddrüsenvolumina und Häufigkeit herdförmiger Veränderungen bei schilddrüsengesunden Männern und Frauen verschiedener Altersklassen.

Thyroid size and the prevalence of focal changes were determined by ultrasound on 450 euthyroid men and women living in Kiel (Schleswig-Holstein). The results were grouped into three age ranges (20-35, 36-50 and 51-85). Volumes were calculated from length x width x thickness x correction factor and expressed in ml. Thyroid volume was increased in 24.7%. Men had significantly larger volumes than women; in both sexes the right lobe was significantly larger than the left one. Focal changes (cysts, nodules, calcifications) were recorded in 21%, with a peak among women in the 36-50 year age group. This latter increase was due to a high incidence of cystic changes. Cysts were noted in 11%, nodules in 10% of the entire sample. A statistically significant increase in the number of nodules was noted for both sexes in the 51-85 age groups. Calcifications were recorded in 2% of cases, with about equal rates among men and women.

[2 cases of Whipple's disease with different outcomes]. / Zwei Fälle von Morbus Whipple mit unterschiedlichem Ausgang.

A 45-year-old man developed migratory arthritis and fever, at first believed to be caused by rheumatoid arthritis. Whipple's disease was eventually diagnosed after a malabsorption syndrome had occurred and biopsies been taken from the distal duodenum and jejunum. The patient was cured after several months on tetracycline. In a second case, a 73-year-old woman, malabsorption of six months' duration resulting from Whipple's disease had brought about such deterioration that after hospitalisation she died despite a correct diagnosis and an appropriate treatment.

[Variable clinical symptoms of hepatocellular carcinoma]. / Unterschiedliche klinische Symptomatik des hepatozellulären Karzinoms.

A hepatocellular carcinoma was found in the cirrhotic liver of a 45-year-old man in the absence of previous hepatitis B and with a normal alpha-fetoprotein level in serum. This is contrasted with the case of a 57-year-old man with "typical" findings of a hepatocellular carcinoma in a small-nodular cirrhotic liver after viral hepatitis B and markedly elevated alpha-fetoprotein.