TRIFLURIDINE/TIPIRACIL (FTD/TPI) with or without bevacizumab in previously treated patients with esophago-gastric adenocarcinoma, a randomised phase III trial

Background

Trifluridine-tipiracil has shown a survival benefit compared with placebo in patients with chemorefractory metastatic esophago-gastric adenocarcinoma. We aimed to compare the efficacy of trifluridine-tipiracil plus bevacizumab vs trifluridine-tipiracil monotherapy in pre-treated patients with metastatic esophago-gastric adenocarcinoma.

Methods

This investigator-initiated, open-label, randomized trial enrolled patients with metastatic esophago-gastric adenocarcinoma. The main inclusion criteria were patients with pre-treated metastatic esophago-gastric adenocarcinoma, and WHO performance status 0 or 1. Participants were randomly assigned (1:1) to receive oral trifluridine-tipiracil (35 mg/m2 twice daily on days 1-5 and 8-12 every 28 days) alone or combined with bevacizumab (5 mg/kg on days 1 and 15) until progression, unacceptable toxicity, or patient decision to withdraw. Randomisation was stratified by sex and treatment line. The primary endpoint was investigator-evaluated progression-free survival. All analyses were based on intention to treat. This trial is registered with EudraCT, 2018-004845-18.

Findings

From Oct 1, 2019, to Sept 30, 2021, 103 patients were enrolled and randomly assigned to trifluridine-tipiracil (n = 53) or trifluridine-tipiracil plus bevacizumab (n = 50). The clinical cut-off date was March 1st, 2023, after a median follow-up of 36.6 months. Median progression-free survival was 3.1 months (95% CI 2.0-4.3) in the trifluridine-tipiracil group vs 3.9 months (3.0-6.3) in the trifluridine-tipiracil plus bevacizumab group (hazard ratio 0.68, 95% CI 0.46-1.02; p = 0.058). The most frequent grade 3 or worse adverse event was neutropenia, observed in 26 (49%) patients in the trifluridine-tipiracil group vs 23 patients (46%) in the trifluridine-tipiracil plus bevacizumab group. At least one hospitalization was observed in 21 patients (40%) in the trifluridine-tipiracil group and 22 patients (44%) in the trifluridine-tipiracil plus bevacizumab group. No deaths were deemed treatment related.

Interpretation

In patients with pre-treated metastatic esophago-gastric cancer, trifluridine-tipiracil plus bevacizumab, compared to trifluridine-tipiracil monotherapy, did not significantly prolong progression-free survival. The combination of trifluridine-tipiracil with bevacizumab was well tolerated without increase in severe neutropenia and no new safety signals.

Funding

Servier, Roche.

Abstract P1-01-16: Performance evaluation of two ready-to-use antibodies under development for the Dako Omnis automated staining platform on breast carcinoma specimens: Anti-estrogen receptor α clone EP1 and anti-progesterone receptor clone PgR 1294

Background: The expression of estrogen receptor alpha (ERα) and progesterone receptor (PR) in breast carcinomas is a strong predictor of the efficacy of hormonal therapy for breast cancer patients as well as providing a degree of prognostic information. Anti-ERα (clone EP1) and anti-PR (clone PgR 1294) configured as FLEX ready-to-use antibodies have been tested on the Dako Omnis automated staining platform. These products are in performance evaluation and are not commercially available. A series of concordance studies were performed to evaluate the performance characteristics of these monoclonal antibodies on breast cancer tissue specimens: anti-ERα clone EP1/Dako Omnis was compared to (a) anti-ERα clone EP1/Autostainer Link 48 (238 specimens) and to (b) anti-ERα clone SP1/Autostainer (116 specimens), and anti-PR clone PgR 1294/Dako Omnis was compared to (a) anti-PR clone PgR 636/Autostainer Link 48 (289 specimens) and to (b) anti-PR clone 16 (Leica Biosystems, Newcastle, UK) (144 specimens). In addition, the specificity of the ER and PR antibodies for Dako Omnis was evaluated on a set of normal tissue specimens.

Methods: Formalin-fixed, paraffin-embedded (FFPE) human breast carcinoma specimens and normal tissues were obtained from commercial providers or local hospitals. The specimens had no associated personal information and were not traceable back to the tissue donors. Tissue pretreatment and immunohistochemical staining were performed using the recommended protocol for each antibody and staining platform. The stained slides were evaluated for nuclear ER or PR expression according to ASCO/CAP guidelines (≥1% cut-off for positive) by pathologists who were blinded from the staining method and specimen ID. The concordance studies included breast cancer specimens covering the clinical range of ER or PR expression with approximately half the specimens in the negative (<1%) category, and at least 10% of the specimens in the weakly positive (≥1 ≤10%) category in each study. Two-sided Wilson Score 95% Confidence Intervals were calculated using JMP software (SAS Institute, USA). For the analytical specificity studies the presence or absence of specific staining in the various normal tissue types was recorded.

Results: High concordance rates were observed with both anti-ERα clone EP1/Dako Omnis and anti-PR clone PgR 1294/Dako Omnis compared to the other ER/PR antibodies, with overall agreement rates exceeding 95% in all of the comparative studies. On a set of normal tissues, specific positive nuclear staining was observed only in tissue types known to express ERα or PR.

Conclusions: Monoclonal antibodies anti-ERα clone EP1 and anti-PR clone PgR 1294 configured as FLEX ready-to-use on Dako Omnis are sensitive and specific assays for detecting estrogen receptor and progesterone receptor in FFPE tissues. In comparison testing for assessment of hormonal receptor status on breast carcinoma specimens, anti-ERα clone EP1/Dako Omnis and anti-PR clone PgR 1294/Dako Omnis were highly concordant with commercially-available ER or PR antibodies.

Citation Format: Viale G, Dell'Orto P, Falzon M, Fält A, Hicks D, Hoff K, Jakobsen K, Jensen LB, Levy YY, McMahon L, Miller K, Russo L. Performance evaluation of two ready-to-use antibodies under development for the Dako Omnis automated staining platform on breast carcinoma specimens: Anti-estrogen receptor α clone EP1 and anti-progesterone receptor clone PgR 1294. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-01-16.

Investigating the underlying mechanisms of temperature-related skin diseases in Atlantic salmon, Salmo salar L., as measured by quantitative histology, skin transcriptomics and composition

Skin integrity is recognized as of vital consideration for both animal welfare and final product quality of farmed fish. This study examines the effects of three different rearing temperatures (4, 10 and 16 °C) on the skin of healthy Atlantic salmon post-smolts. Changes in skin condition were assessed by the means of skin composition analyses, quantitative histology assessments and transcriptome analysis. Level of protein, vitamin C and vitamin E was significantly higher at 16 °C compared with 4 °C. Quantitative histology measurements showed that the epidermal thickness decreased from low to high temperature, whereas the epidermal area comprising mucous cells increased. The difference was only significant between 4 and 16 °C. Both high and low temperature exhibited significant changes in the skin transcriptome. A number of immune-related transcripts responded at both temperatures. Contrary to well-described immunosuppressive effects of low water temperature on systemic immunity, a subtle increase in skin-mediated immunity was observed, suggesting a pre-activation of the mucosal system at 4 °C. Upregulation of a number of heat-shock proteins correlating with a decrease in epidermal thickness suggested a stress response in the skin at high temperature. The results demonstrate distinctive temperature-related effects on the skin of Atlantic salmon.

Proteomic analysis of epidermal mucus from sea lice-infected Atlantic salmon, Salmo salar L

Health diets that contain immunostimulants and other functional ingredients can strengthen the immune response in Atlantic salmon, Salmo salar, and thereby reduce sea lice, Lepeophtheirus salmonis, infection levels. Such diets can be used to supplement other treatments and will potentially reduce the need for delousing and medication. A sea lice infection trial was conducted on fish with an average weight of 215 g. One control diet and four experimental diets containing functional ingredients were produced. The diets were fed to salmon for 4 weeks before infection with sea lice copepodids. When lice had developed to chalimus III/IV, 88 fish per diet were examined for lice loads. Mucus samples from fish fed the different diets were taken before and after lice infection. Mass spectrometry-based proteomics was used to characterize the protein composition in the epidermal mucus of Atlantic salmon and to identify quantitative alterations in protein expression. Multivariate analysis of the generated data sets was performed to identify protein biomarkers. Putative biomarkers associated with functional feed intake and with sea lice infection have been identified and can form the basis for strategic validation experiments with selected functional feeds.

A classification system for plasmids from enterococci and other Gram-positive bacteria

A classification system for plasmids isolated from enterococci and other Gram-positive bacteria was developed based on 111 published plasmid sequences from enterococci and other Gram-positive bacteria; mostly staphylococci. Based on PCR amplification of conserved areas of the replication initiating genes (rep), alignment of these sequences and using a cutoff value of 80% identity on both protein and DNA level, 19 replicon families (rep-families) were defined together with several unique sequences. The prevalence of these rep-families was tested on 79 enterococcal isolates from a collection of isolates of animal and human origin. Difference in prevalence of the designed rep-families were detected with rep(9) being most prevalent in Enterococcus faecalis and rep(2) in Enterococcus faecium. In 33% of the tested E. faecium and 32% of the tested E. faecalis no positive amplicons were detected. Furthermore, conjugation experiments were performed obtaining 30 transconjugants when selecting for antimicrobial resistance. Among them 19 gave no positive amplicons indicating presence of rep-families not tested for in this experimental setup.

Frequent amplifications and deletions of G1/S-phase transition genes, CCND1 and MYC in early breast cancers: a potential role in G1/S escape

Uncontrolled growth of cancer cells can be related to dysfunctional cell cycle control, including entry into S-phase, initiating cell division. Cyclin CCND3 and CCNE1 along with CDK2 and CDK6 regulate this checkpoint, and genetic changes, detectable by fluorescence in situ hybridization, are hypothesized to increase the aggressiveness of breast cancer, thereby influencing patient survival. Genomic change was investigated in 106 primary breast cancer samples, where the combined gene copy number changes in one of these four cell cycle regulatory factors was observed in 22% of the 98 tumors of successful analysis, distributed with 15 deletions and 7 amplifications. A trend towards decreased survival was observed with the aberrations, suggesting a prognostic potential of this set of markers, which was supported by an association with tumor grade. For validation of the new set of FISH probes for the G1/S-phase cell cycle factors, two additional markers, frequently amplified in breast cancers, were included in this study: The G1/S phase control gene CCND1 and the proliferation marker MYC. Both markers were amplified in 14% and deleted in 5% of the cases. This is the first report of genomic deletions of MYC in breast cancer.

Peanut cross-reacting allergens in seeds and sprouts of a range of legumes

BACKGROUND

Recently, peanut-allergic patients have reported symptoms upon ingestion of bean sprouts produced from various legumes.

OBJECTIVE

This study was designed to identify immunoreactivity to seeds and sprouts of legumes other than peanut in sera from peanut-allergic patients.

METHODS

Crude protein extracts of seeds and sprouts (comprising cotelydons and hypocotyls/epicotyls) of peanut, soybean, green pea, blue lupine, mung bean, alfalfa, broad bean, and azuki bean were prepared. The reactivity of sera from 10 peanut-allergic patients to these extracts was analysed by indirect histamine release (HR), enzyme-allergosorbent test (EAST), EAST inhibition, and Western blots. Skin prick tests (SPTs) were performed on the patients with fresh legume seeds as well as four commercial legume sprouts, and food challenges with soybean, pea, and lupine were performed on a subgroup of the patients.

RESULTS

All legume seeds and commercial sprouts induced positive SPTs in some of the patients. Indirect HR experiments indicated an extensive co-reactivity between peanut and the legumes, and cross-reactivity was observed for soybean, pea, and lupine seeds as well as lupine hypocotyls in EAST inhibition experiments. Of the 16 protein extracts, soybean, pea, and lupine seed extracts produced visible bands in Western blots.

CONCLUSION

The symptoms reported by peanut-allergic patients after legume sprout intake might be caused by cross-reactivity of peanut-specific antibodies. The intake of raw legume sprouts might cause symptoms in peanut-allergic patients.

Using data on resistance prevalence per sample in the surveillance of antimicrobial resistance

OBJECTIVES

In most existing antimicrobial resistance monitoring programmes, one single bacterial colony from each collected sample is susceptibility tested against a panel of antimicrobials. Detecting the proportion of colonies resistant to different antimicrobials in each sample can provide quantitative data on antimicrobial resistance (resistance prevalence per sample).

METHODS

In this study, a total of 98 faecal samples from slaughter pigs were tested for tetracycline and sulphonamide resistance in Escherichia coli using the single colony method, and these results were compared with the results obtained using the resistance prevalence per sample method.

RESULTS

The results obtained by the resistance prevalence per sample method showed a lower occurrence of resistance. Tetracycline resistance in E. coli was found in 36.7% of the samples using the single colony method, while the mean tetracycline resistance prevalence was 22.5% using the resistance prevalence per sample method. Similarly, sulphonamide resistance was 32.7% using the single colony method and 19.6% when using the resistance prevalence per sample method. Although different estimates were obtained by each method, the correlation test and the regression model demonstrated that there is a significant association between the results obtained using both methods (P value <0.01) for both antimicrobials tested.

CONCLUSIONS

To support risk assessment and analysis of the association between consumption of antimicrobials and occurrence of resistance, there is a need to move towards a more quantitative approach when dealing with antimicrobial resistance in a population, and the resistance prevalence per sample method can provide some of this additional information.

A possible mechanism of macrolide resistance among multiple resistant Campylobacter jejuni and Campylobacter coli isolated from Thai children during 1991-2000

A total of 495 Campylobacterjejuni and 122 C. coli isolated from Thai children were screened for macrolide (erythromycin and azithromycin) resistance by disk diffusion assay. Minimum inhibitory concentrations for erythromycin, azithromycin, nalidixic acid, ciprofloxacin, tetracycline, streptomycin, gentamicin and chloramphenicol were further determined for these macrolide-resistant Campylobacter isolates. Presence of known point mutations resulting in reduced susceptibility to macrolides was investigated by PCR and DNA sequencing. Seventeen percent (23/122) of C. coli and 2.4% (12/495) of C. jejuni isolates were resistant to macrolides. By sequencing domain V of the 23S ribosomal DNA from all 35 macrolide-resistant isolates, a known point mutation of 23S rRNA associated with reduced susceptibility to macrolides was detected in all isolates except one. Among the macrolide-resistant isolates, all were multiply resistant to nalidixic acid and ciprofloxacin, of which the latter is the preferred antimicrobial used for diarrheal treatment in Thailand. Furthermore, most macrolide-resistant isolates were also resistant to tetracycline and streptomycin. The spread of macrolide and quinolone resistant Campylobacter should be monitored closely in Thailand and elsewhere as these antimicrobials are preferred drugs for treatment of diarrhea.

Distribution of diarrhetic shellfish poisoning toxins in consignments of blue mussel

Data describing the distribution of diarrhetic shellfish poisoning toxins in 13 consignments of Danish-produced blue mussels are reported. The content of diarrhetic shellfish poisoning toxins was measured by a liquid chromatography coupled with tandem mass spectrometry detection method, and mean levels in the 13 consignments varied from 58 to 243 microg kg(-1). The distributions of diarrhetic shellfish poisoning toxins in the consignments were relatively homogeneous as the relative standard deviation of the content varied from 7 to 19%. The results are discussed in relation to food safety, the uncertainty of sampling and analysis, and the newly introduced European Union maximum levels of marine biotoxins in seafood products.

Diarrhetic shellfish poisoning toxin esters in Danish blue mussels and surf clams

Until recently, little focus was given to the presence of diarrhetic shellfish poisoning (DSP) toxin esters in seafood products. However, during the last few years, the occurrence of a high percentage of esters of the total amount of DSP toxins present in some seafood products has been observed. Samples of Danish surf clams (Spisola spp.) and blue mussels (Mytilus edulis) from 1999-2004 were analysed by liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS) for the presence of DSP toxin esters. The samples contained only okadaic acid and esters of okadaic acid. The level of total okadaic acid equivalents ranged from 224 to 2516 microg kg-1 in surf clams. The percentage of okadaic acid esters of the total okadaic acid equivalents ranged from 83 to 98%, mean 95%. The level of total okadaic acid equivalents ranged from 43 to 1631 microg kg-1 in blue mussels. The percentage of okadaic acid esters of the total okadaic acid equivalents ranged from 21 to 86%, mean 59%. The probability of a high percentage of okadaic acid esters seems to increase with higher amounts of total okadaic acid equivalents in the bivalves. The large prevalence of DSP toxin esters are of particular importance because of the increased use of chemical methods instead of mouse bioassay for the detection of DSP toxicity.

Response rates to oestrogen treatment in perimenopausal women: 5-year data from the Danish Osteoporosis Prevention Study (DOPS)

OBJECTIVE

To characterise women with no response or with a good response to hormone replacement therapy (HRT), evaluated by change in bone mineral density (BMD).

DESIGN

Nested case-control study within a comprehensive cohort study.

SUBJECTS AND METHODS

In the Danish Osteoporosis Prevention Study (DOPS), perimenopausal women were allocated to either HRT or no HRT. In the present study, we included 466 women who had been treated with HRT for 5 years and 466 untreated women from the same cohort. Non-responders were women in the treatment group, who decreased in BMD more than the mean decrease observed in the untreated group. Good responders were women with a larger increase in BMD than the upper 95% percentile of untreated women. Baseline characteristics were evaluated as predictors of response to HRT.

RESULTS

8.4 and 5.6% were classified as non-responders, whereas 25 and 57% were good responders according to changes in BMD of the femoral neck and lumbar spine, respectively. Combining measuring sites, 2.6% were non-responders and 20% were good responders. Non-responders at the femoral neck were more often smokers and had a lower spine BMD. Good responders were older, had a higher body weight, and higher alcohol consumption. In addition, good responders at both measurements sites had a lower BMD at the total hip.

CONCLUSION

A favourable BMD response to HRT can be expected in most post-menopausal women especially if they are non-smokers with a moderate--as opposed to low--alcohol intake, a high body mass and a low initial hip BMD.

Reactions of [NH3+*, H2O] with carbonyl compounds: a McLafferty rearrangement within a complex?

The reactions of the water solvated ammonia radical cation [NH(3)(+*), H(2)O] with a variety of aldehydes and ketones were investigated. The reactions observed differ from those of low energy aldehydes and ketones radical cations, although electron transfer from the keto compound to ionized ammonia is thermodynamically allowed within the terbody complexes initially formed. The main process yields an ammonia solvated enol with loss of water and an alkene. This process corresponds formally to a McLafferty fragmentation within a complex. With aldehydes, another reaction can take place, namely the transfer of the hydrogen from the CHO group to ammonia, leading to the proton bound dimer of ammonia and water, and to the NH(4)(+) cation. Comparison between the available experimental results leads to the conclusion that the McLafferty fragmentation occurs within the terbody complex initially formed, with no prior ligand exchange, the water molecule acting as a spectator partner.

Long term prognosis of fatty liver: risk of chronic liver disease and death

BACKGROUND AND AIMS

Fatty liver is a common histological finding in human liver biopsy specimens. It affects 10-24% of the general population and is believed to be a marker of risk of later chronic liver disease. The present study examined the risk of development of cirrhotic liver disease and the risk of death in a cohort diagnosed with pure fatty liver without inflammation.

METHODS

A total of 215 patients who had a liver biopsy performed during the period 1976-1987 were included in the study. The population consisted of 109 non-alcoholic and 106 alcoholic fatty liver patients. Median follow up time was 16.7 (0.2-21.9) years in the non-alcoholic and 9.2 (0.6-23.1) years in the alcoholic group. Systematic data collection was carried out by review of all medical records. All members of the study cohort were linked through their unique personal identification number to the National Registry of Patients and the nationwide Registry of Causes of Death, and all admissions, discharge diagnoses, and causes of death were obtained.

RESULTS

In the non-alcoholic fatty liver group, one patient developed cirrhosis during the follow up period compared with 22 patients in the alcoholic group. Survival estimates were significantly (p<0.01) different between the two groups, for men as well as for women, with a higher death rate in the alcoholic fatty liver group. Survival estimates in the non-alcoholic fatty liver group were not different from the Danish population.

CONCLUSIONS

This study revealed that patients with type 1 non-alcoholic fatty liver disease have a benign clinical course without excess mortality.

Persistence of vancomycin-resistant enterococci (VRE) in broiler houses after the avoparcin ban

The glycopeptide growth promoter avoparcin was banned from animal production in the EU in 1997 due to concern for the spread of vancomycin-resistant enterococci (VRE) from food animals to humans. In recent Norwegian and Danish studies, extensive occurrence of VRE on broiler farms and in broiler flocks after the avoparcin ban has been reported. The present study was undertaken to investigate the epidemiology of VRE on broiler farms in the absence of the selective pressure exerted by avoparcin. Environmental samples were obtained from five broiler houses after depopulation, cleaning, and disinfection of the houses between rotations, and two consecutive broiler flocks from each house were sampled by taking cloacal swabs from the broilers at the time of slaughter. A total of 69 vancomycin-resistant Enterococcus faecium isolates obtained from broiler flocks and broiler houses were subjected to molecular typing by pulsed-field gel electrophoresis (PFGE). Forty-one PFGE-profiles were observed. VRE with indistinguishable or highly similar PFGE profiles were isolated from consecutive broiler flocks and from environmental samples from the houses in which the flocks were reared, whereas VRE-isolates from different broiler houses and from flocks reared in different houses appeared to be genetically unrelated. These findings indicated that VRE was transmitted between consecutive broiler flocks by clones of resistant bacteria surviving in the broiler houses despite cleaning and disinfection between rotations. Thus, the extensive occurrence of VRE in broiler flocks after the avoparcin ban may be explained by persistence of VRE in the broiler house environment.

Hormone replacement therapy dissociates fat mass and bone mass, and tends to reduce weight gain in early postmenopausal women: a randomized controlled 5-year clinical trial of the Danish Osteoporosis Prevention Study

The aim of this study was to study the influence of hormone replacement therapy (HRT) on weight changes, body composition, and bone mass in early postmenopausal women in a partly randomized comprehensive cohort study design. A total of 2016 women ages 45-58 years from 3 months to 2 years past last menstrual bleeding were included. One thousand were randomly assigned to HRT or no HRT in an open trial, whereas the others were allocated according to their preferences. All were followed for 5 years for body weight, bone mass, and body composition measurements. Body weight increased less over the 5 years in women randomized to HRT (1.94 +/- 4.86 kg) than in women randomized to no HRT (2.57 +/- 4.63, p = 0.046). A similar pattern was seen in the group receiving HRT or not by their own choice. The smaller weight gain in women on HRT was almost entirely caused by a lesser gain in fat. The main determinant of the weight gain was a decline in physical fitness. Women opting for HRT had a significantly lower body weight at inclusion than the other participants, but the results in the self-selected part of the study followed the pattern found in the randomized part. The change in fat mass was the strongest predictor of bone changes in untreated women, whereas the change in lean body mass was the strongest predictor when HRT was given. Body weight increases after the menopause. The gain in weight is related to a decrease in working capacity. HRT is associated with a smaller increase in fat mass after menopause. Fat gain protects against bone loss in untreated women but not in HRT-treated women. The data suggest that women's attitudes to HRT are more positive if they have low body weight, but there is no evidence that the conclusions in this study are skewed by selection bias.

Reduced antimicrobial potencies of oxytetracycline, tylosin, sulfadiazin, streptomycin, ciprofloxacin, and olaquindox due to environmental processes

The stability of oxytetracycline (OTC), tylosin (TYL), sulfadiazin (SDZ), streptomycin (ST), ciprofloxacin (CF) and olaquindox (O) was examined in environmentally relevant matrices, such as soil interstitial water and sewage sludge water. Compounds were assessed in both aerobic (OTC, TYL, SDZ, ST, and CF) and anaerobic experiments (OTC, TYL, and O) using analytical measurements (UV spectrophotometry or HPLC) combined with a growth inhibition pour plate assay using activated sludge bacteria. (OTC was additionally assessed using a soil bacterial assay.) This combination of results enabled the assessment of whether a loss in antibacterial potency was reflected in a similar reduction of substance concentration. If a potency reduction is not reflected in a decreased substance concentration, the results may indicate the formation of less potent degradation products possessing the same chromophoric system (same UV absorbance maximum) as the parent compound. With the exception of ST and CF, the antimicrobial agents generally lost a considerable amount of their antimicrobial potency in aerobic experiments. In the anaerobic experiments having either an experimental duration of 21 or 100 days only OTC retained potency. These results correspond well with the fact that several degradation products were encountered in the study for this compound

The pharmacokinetics, pharmacodynamics, safety and tolerability of NN2211, a new long-acting GLP-1 derivative, in healthy men

AIMS/HYPOTHESIS

Glucagon-like peptide-1 (GLP-1), a polypeptide hormone secreted by the l-cells in the gastrointestinal tract, has shown promising effects as a new treatment modality for patients with Type II (non-insulin-dependent) diabetes mellitus. However, the pharmacokinetic profile of native GLP-1 with a rapid elimination has limited its therapeutic potential. NN2211 is a fatty acid derivative of GLP-1, which pre-clinically has shown a protracted pharmacokinetic profile, while maintaining its biological activity. This study aimed to investigate the safety, tolerability, pharmacokinetics and pharmacodynamics of NN2211 in healthy male subjects following seven days treatment.

METHODS

In a double-blind, randomized, dose escalation, placebo controlled study, healthy male subjects were enrolled at five consecutive dose levels of NN2211 (1.25, 5.0, 7.5, 10.0, 12.5 microg/kg). Six subjects were allocated at random at each dose level to active or placebo treatment with a ratio of 2:1. Dosing with NN2211 was performed on day 1, and days 5-11. The 84-h pharmacokinetics and 24-h glucose and insulin profiles were assessed on day 1 and day 11.

RESULTS

Following s. c. administration the half-life of NN2211 was found to be 12.6 +/- 1.1 h, with a subsequent accumulation index after a daily dose for seven days of 1.4-1.5. There were dose-proportional increases in exposure (AUC and C(max)) with increasing doses. Overall, there were no statistically significant differences from placebo in the 24-h glucose and insulin profiles. In subjects treated with NN2211 rather than placebo, there was a higher incidence of adverse events, most notably dizziness and adverse events related to the gastrointestinal system. There were no serious adverse events but three subjects were nonetheless withdrawn because of dizziness, fever and nausea. There were no clinically relevant changes in vital signs, ECG parameters, physical examination or safety laboratory parameters. A significantly lower diuresis was observed in the actively treated subjects, without a clinically relevant change in packed cell volume.

CONCLUSIONS/INTERPRETATION

This study shows NN2211 has a pharmacokinetic profile supporting a daily dose in human beings, but also that subjects treated with NN2211 rather than placebo, had a higher incidence of adverse events, most notably dizziness and adverse events related to the gastrointestinal system.

Evaluation of methods for prediction of bone mineral density by clinical and biochemical variables in perimenopausal women

OBJECTIVES

to predict spinal and femoral bone mineral density (BMD) in perimenopausal women from simple clinical and biochemical variables.

METHODS

2016 women 3-24 months past last menstrual bleeding. Mean age 50.1+/-2.8 years. Age, height, weight, number of full term pregnancies, weekly hours of physical activity, sunbathing habits, use of sun bed, daily intake of calcium and vitamin D, smoking habits, consumption of alcohol, coffee, and tea, history of forearm or femoral neck fractures among the parents, serum osteocalcin (S-OC), serum bone specific isoenzyme of alkaline phosphatase (BSAP), and urine hydroxyproline/creatinine ratio (U-OHP) were used as predictors in three different mathematical models. Lumbar spine (L2-L4) and femoral neck BMD were measured by DEXA. Three mathematical models (multiple regression, logistic regression, and discriminant analysis) were applied.

RESULTS

the multiple regression explained 19-21% of the total variation, and the logistic regression and discriminant function had a sensitivity between 53 and 67% with specificity ranging from 67 to 80%. Age, S-OC, serum bone specific alkaline phosphatase, and a maternal history of forearm or femoral neck fractures seemed to be reproducible risk factors for low bone mineral density irrespective of the mathematical model applied. When applied to a separate population, the models performed poorly.

CONCLUSIONS

Simple clinical and biochemical variables are not useful to predict spinal and femoral BMD in the individual perimenopausal woman.

[Hormone replacement therapy reduces the risk of forearm fracture in postmenopausal women. Results of the Danish Osteoporosis Prevention Study]

In a prospective, controlled, comprehensive cohort trial of 2,016 healthy early postmenopausal women aged 45-58 years we studied fracture prevention through the use of oestrogen. There were two main study arms: a randomised arm (randomised to HRT [n = 502] or not [n = 504]) and a non-randomised arm (on HRT [n = 221] or not [n = 789] by own choice). After five years, an intention-to-treat analysis (n = 2,016) showed a reduction in the overall fracture risk (RR = 0.73, 95% CI: 0.50-1.05) and in the forearm fracture risk (RR = 0.45, 95% CI: 0.22-0.90) with oestrogen. Restriction of the analysis to women who had adhered to their initial allocation of either oestrogen (n = 395) or no oestrogen (n = 977) showed a significant reduction in both the overall fracture risk (RR = 0.61, 95% CI: 0.39-0.97) and the risk of forearm fractures (RR = 0.24, 95% CI: 0.09-0.69). We conclude that it is possible to reduce the number of forearm fractures in early postmenopausal women by the use of oestrogen as primary prevention.

Effect of pheromone induction on transfer of the Enterococcus faecalis plasmid pCF10 in intestinal mucus ex vivo

The effect of synthetic sex pheromone on pheromone-inducible conjugation between the isogenic Enterococcus faecalis strains OG1RF and OG1SS was investigated in (i) Todd-Hewitt broth medium and (ii) intestinal mucus isolated from germ-free rats. In broth, the presence of synthetic pheromone cCF10 had no detectable effect on the transfer kinetics observed for the tetracycline resistance encoding plasmid pCF10. In mucus, presence of the same pheromone significantly increased the transfer efficiency observed during the first 2 h of conjugation, while the effect was less pronounced later in the experiment. We suggest that due to differences in diffusion rates and medium-binding of the pheromones, the effect of the synthetic cCF10 was immediately dominated by the effect of pheromones produced by the recipient E. faecalis strain in broth, while this happened later in mucus.

Indication of transposition of a mobile DNA element containing the vat(D) and erm(B) genes in Enterococcus faecium

The vat(D) and erm(B) genes encoding streptogramin resistance in Enterococcus faecium transferred together, and a direct physical link between erm(B) and vat(D) was detected. Both the vat(D) and erm(B) probes hybridized to fragments of different sizes in the donor and transconjugants, which indicated a transposition event.

Antimicrobial resistance among Pseudomonas spp. and the Bacillus cereus group isolated from Danish agricultural soil

From four Danish pig farms, bacteria of Pseudomonas spp. and the Bacillus cereus group were isolated from soil and susceptibility towards selected antimicrobials was tested. From each farm, soil samples representing soil just before and after spread of animal waste and undisturbed agricultural soil, when possible, were collected. Soil from a well-characterized Danish farm soil (Højbakkegaard) was collected for comparison. The Pseudomonas spp. and B. cereus were chosen as representative for Gram-negative and Gram-positive indigenous soil bacteria to test the effect of spread of animal waste on selection of resistance among soil bacteria. No variations in resistance levels were observed between farms; but when the four differently treated soils were compared, resistance was seen for carbadox, chloramphenicol, nalidixan (nalidixic acid), nitrofurantoin, streptomycin and tetracycline for Pseudomonas spp., and for bacitracin, erythromycin, penicillin and streptomycin for the B. cereus group. Variations in resistance levels were observed when soil before and after spread of animal waste was compared, indicating an effect from spread of animal waste.

[Long-term oxygen therapy (LTOT) in chronic obstructive lung disease (COL)]

A substantive amendment to this systematic review was last made on 12 April 1999. Cochrane reviews are regularly checked and updated if necessary.

BACKGROUND AND OBJECTIVES

To determine the effect of domiciliary oxygen therapy on survival and quality of life in patients with chronic obstructive pulmonary disease.

SEARCH STRATEGY

Randomised controlled trials (RTCs) were identified using the Cochrane Airways Group Chronic Obstructive Pulmonary Disease (COPD) register using the search terms: home or domiciliary and oxygen.

SELECTION CRITERIA

Any randomised controlled trial in patients with hypoxia and chronic obstructive pulmonary disease that compared long term domiciliary or home oxygen therapy with a control treatment.

DATA COLLECTION AND ANALYSIS

Data extraction was performed independently by two reviewers.

MAIN RESULTS

Four randomised controlled trials were identified. Data from none of these trials could be aggrigated because of differences in trial design and patient selection. Trial 1, continuous oxygen therapy versus nocturnal oxygen therapy: there was a significant improvement in mortality after 24 months (Peto odds ratio 0.45, 95% confidence interval 0.25 to 0.81). Trial 2, oxygen versus no oxygen: there was a significant improvement over five years in mortality in the group receiving oxygen (Peto odds ratio 0.42, 95% confidence interval 0.18 to 0.98). Trial 3, nocturnal oxygen versus no oxygen in patients with arterial desaturation at night: there was no difference in mortality at 36 months. Trial 4, long term oxygen versus no oxygen in moderate hypoxaemia: there was no effect on survival for up to three years of follow up. REVIEWERS' CONCLUSION: Long term oxygen therapy improves survival in a selected group of COPD patients with severe hypoxaemia (arterial PO2 less than 8.0 kPa). Long term oxygen does not appear to improve survival in patients with moderate hypoxia or those who only have arterial desaturation at night.

Construction of a high affinity zinc binding site in the metabotropic glutamate receptor mGluR1: noncompetitive antagonism originating from the amino-terminal domain of a family C G-protein-coupled receptor

The metabotropic glutamate receptors (mGluRs) belong to family C of the G-protein-coupled receptor (GPCR) superfamily. The receptors are characterized by having unusually long amino-terminal domains (ATDs), to which agonist binding has been shown to take place. Previously, we have constructed a molecular model of the ATD of mGluR1 based on a weak amino acid sequence similarity with a bacterial periplasmic binding protein. The ATD consists of two globular lobes, which are speculated to contract from an "open" to a "closed" conformation following agonist binding. In the present study, we have created a Zn(2+) binding site in mGluR1b by mutating the residue Lys(260) to a histidine. Zinc acts as a noncompetitive antagonist of agonist-induced IP accumulation on the K260H mutant with an IC(50) value of 2 microm. Alanine mutations of three potential "zinc coligands" in proximity to the introduced histidine in K260H knock out the ability of Zn(2+) to antagonize the agonist-induced response. Zn(2+) binding to K260H does not appear to affect the dimerization of the receptor. Instead, we propose that binding of zinc has introduced a structural constraint in the ATD lobe, preventing the formation of a "closed" conformation, and thus stabilizing a more or less inactive "open" form of the ATD. This study presents the first metal ion site constructed in a family C GPCR. Furthermore, it is the first time a metal ion site has been created in a region outside of the seven transmembrane regions of a GPCR and the loops connecting these. The findings offer valuable insight into the mechanism of ATD closure and family C receptor activation. Furthermore, the findings demonstrate that ATD regions other than those participating in agonist binding could be potential targets for new generations of ligands for this family of receptors.

Bone minerals changes in obese women during a moderate weight loss with and without calcium supplementation

A significant relationship between body weight (BW) and bone mass (BM) has been established previously. A diet-induced weight loss is accompanied by a significant decrease in bone mineral density (BMD) and total body bone mineral (TBBM), but the underlying mechanisms are not clarified. Sixty-two obese women were included in the study. Dual-energy X-ray absorptiometry (DXA) and measurements of a series of calcium-regulating hormones and biochemical markers of bone turnover were performed at baseline and after 1 month and 3 months on a low calorie diet. Thirty of the women were randomized to a daily supplement of 1 g of calcium. After an additional 3 months without dietary prescriptions or calcium supplements, a subgroup of 48 subjects (24 from each group) were scanned again using DXA. There was a significant decrease in TBBM after 1 month and 3 months. A similar pattern was observed in the bone mineral content (BMC) of the lumbar spine in the patients who did not receive a calcium supplement, whereas no changes occurred in the supplemented group. The initial calcium supplementation seemed to protect against bone loss in the lumbar spine but not in the TBBM. In the nonsupplemented group, a statistically significant inverse correlation was found between the calcium/creatinine ratio in the morning urine and the changes in BMC of the lumbar spine. Such a relationship was not seen in the calcium-supplemented group. In the nonsupplemented group, no significant biochemical changes were observed, whereas a significant decrease in serum parathyroid hormone (PTH) was seen in the calcium-supplemented group. This might explain some of the protective effects of calcium supplementation on trabecular bone mass. We conclude that a diet-induced weight loss is accompanied by a generalized bone loss, which probably is explained mainly by a reduced mechanical strain on the skeleton. This loss can be partly inhibited by a high calcium intake. Therefore, a calcium supplementation should be recommended during weight loss, even if the diet contains the officially recommended amounts of calcium.

Presence of variations in ribosomal protein L16 corresponding to susceptibility of enterococci to oligosaccharides (Avilamycin and evernimicin)

Fragments (414 bp) of the gene-encoding ribosomal protein L16 from Enterococcus faecium and Enterococcus faecalis that were resistant and susceptible to the oligosaccharide antibiotics avilamycin and evernimicin (SCH 27899) were sequenced and compared. The susceptible E. faecalis and E. faecium isolates had sequences that were similar to those of the type strains. All resistant E. faecalis isolates contained the same base pair variation [CGT (Arg-56) --> CAT (His-56)]. The same variation and two additional variations [ATC (Ile-52) --> ACC (Thr-52) and ATC (Ile-52) --> AGC (Ser-52)] were found in the resistant E. faecium isolates. This study indicated that resistance to the oligosaccharides in enterococci is associated with variations in the ribosomal protein L16.

A new insulin immunoassay specific for the rapid-acting insulin analog, insulin aspart, suitable for bioavailability, bioequivalence, and pharmacokinetic studies

OBJECTIVES

To validate a specific enzyme-linked immunosorbent assay for the rapid-acting human insulin analogue, insulin aspart, in human serum, human plasma, and porcine plasma.

DESIGN AND METHODS

For the enzyme-linked immunosorbent assay, two murine monoclonal antibodies were developed that bind to two different epitopes on the insulin aspart molecule. Key parameters for validation were imprecision, accuracy, matrix effects, dilution-linearity, and cross-reactivity.

RESULTS

No cross-reactivity was found with human and porcine insulin, human proinsulin, or human C-peptide. The assay is sensitive (limit of quantification = 11.5 pmol/L), accurate (95-107% recovery with human serum, human plasma, and porcine plasma in the range 16-800 pmol/L), and has a 14.7% total imprecision within the entire analytical range. Dilution of samples gave linear results with human serum as the diluent.

CONCLUSIONS

The insulin aspart-specific enzyme-linked immunosorbent assay described in this study is well suited to study the bioavailability, bioequivalence, and pharmacokinetics of this insulin analogue.

Hormonal replacement therapy reduces forearm fracture incidence in recent postmenopausal women - results of the Danish Osteoporosis Prevention Study

OBJECTIVES

To study the fracture reducing potential of hormonal replacement therapy (HRT) in recent postmenopausal women in a primary preventive scenario.

METHODS

Prospective controlled comprehensive cohort trial: 2016 healthy women aged 45-58 years, from three to 24 months past last menstrual bleeding were recruited from a random sample of the background population. Mean age was 50. 8+/-2.8 years, and the number of person years followed was 9335.3. There were two main study arms: a randomised arm (randomised to HRT; n=502, or not; n=504) and a non-randomised arm (on HRT; n=221, or not; n=789 by own choice). First line HRT was oral sequential oestradiol/norethisterone in women with intact uterus and oral continuous oestradiol in hysterectomised women.

RESULTS

After five years, a total of 156 fractures were sustained by 140 women. There were 51 forearm fractures in 51 women. By intention-to-treat analysis (n=2016), overall fracture risk was borderline statistically significantly reduced (RR=0.73, 95% CI: 0.50-1.05), and forearm fracture risk was significantly reduced (RR=0.45, 95% CI: 0.22-0.90) with HRT. Restricting the analysis to women who had adhered to their initial allocation of either HRT (n=395) or no HRT (n=977) showed a significant reduction in both the overall fracture risk (RR=0.61, 95% CI: 0.39-0.97) and the risk of forearm fractures (RR=0.24, 95% CI: 0.09-0.69). Compliance with HRT was 65% after five years.

CONCLUSIONS

It is possible to reduce the number of forearm fractures and possibly the total number of fractures in recent postmenopausal women by use of HRT as primary prevention.

Associations between the use of antimicrobial agents for growth promotion and the occurrence of resistance among Enterococcus faecium from broilers and pigs in Denmark, Finland, and Norway

This study compares the susceptibility of Enterococcus faecium isolated from pigs and poultry in Denmark, Finland, and Norway to antimicrobial agents used for growth promotion. E. faecium was isolated from 211 broilers and 55 pigs in Denmark in 1997, from Norwegian 55 poultry farms (turkey and broiler farms) and 4 swine farms between 1995 and 1997, and Finnish poultry (52) and swine (43) in 1996 and examined for susceptibility to avilamycin, avoparcin, bacitracin, flavomycin, monensin, salinomycin, spiramycin, tylosin, and virginiamycin. Only a limited number of isolates were categorized as resistant to monensin or salinomycin. In general, an association between the usage of antimicrobial agents in the respective countries and the occurrence of associated resistance was observed. Resistance to avilamycin was frequently observed among isolates from broilers in Denmark, where avilamycin has been used, whereas all isolates from Finland and Norway, where these drugs have not been used, were susceptible. The same phenomenon could be observed for avoparcin, bacitracin, tylosin, and virginiamycin; resistance was frequently observed among isolates from where these antimicrobials have been widely used, but rarely among isolates from where the use has been limited. Also for avoparcin and bacitracin, an association between usage and occurrence of resistance was observed. All isolates categorized as avoparcin resistant contained the vanX gene; isolates from broilers had the T variant in position 8,234 and isolates from pigs the G variant. Three (1%) of the 222 isolates resistant to tylosin contained the ermA gene and 196 (88%) ermB. Sixteen (11%) of the 146 virginiamycin-resistant isolates from broilers and two (7%) of the 27 virginiamycin-resistant isolates from pigs in Denmark contained the satA gene, whereas satA was not observed among any of the virginiamycin-resistant isolates from Finland. A total of 72% of the virginiamycin-resistant E. faecium from broilers in Denmark and all nine virginiamycin-resistant E. faecium from Finland contained satG. This gene was also observed among two (7%) of the virginiamycin-resistant isolates from pigs in Denmark. This study indicates that the use of antimicrobial agents for growth promotion in Denmark, Finland, and Norway have selected for resistance to most of these drugs among E. faecium in food animals.

Antimicrobial susceptibility and presence of resistance genes in staphylococci from poultry

The species distribution, susceptibility to 19 antimicrobial agents and presence of selected genes encoding resistance to macrolides, streptogramins and tetracyclines were examined among 118 staphylococcal isolates from infections of poultry in Denmark. Isolates were identified using a combination of conventional biochemical testing and 16S rDNA sequencing. The most common species were Staphylococcus aureus (83), Staphylococcus hyicus (11), Staphylococcus xylosus (9) and Staphylococcus cohnii (6). The isolates were susceptible to most antimicrobials tested. A high frequency of S. aureus (30%) was resistant to ciprofloxacin. Only six (7%) S. aureus isolates and one Staphylococcus saprophyticus were penicillin resistant. Resistance to sulphamethoxazole was observed among 16 (19%) of S. aureus isolates and two coagulase negative staphylococci (CNS). Twenty (24%) of the S. aureus isolates were resistant to erythromycin and 19 of these isolates contained the ermA gene, whereas the remaining isolate contained the ermC gene. Eleven (48%) of the novobiocin resistant CNS were resistant to erythromycin and all these isolates contained the ermA gene. Two isolates identified as S. xylosus, were found to be resistant to streptogramins and both contained the vatB- and the vgaB-genes. Thirty-nine (47%) of the S. aureus isolates, three of nine S. hyicus and eight of the 23 novobiocin resistant CNS were tetracycline resistant and all contained the tet(K) gene. A single S. aureus isolate also contained the tet(M) gene. The present study showed a frequent occurrence of resistance to fluoroquinolones, tetracycline and macrolides among staphylococci isolated from broilers in Denmark, whereas the occurrence of resistance to other antimicrobial agents remains low. Similar genes, encoding resistance to erythromycin, tetracycline and streptogramins to those previously observed, were detected.

Persistence of a Salmonella enterica serotype typhimurium clone in Danish pig production units and farmhouse environment studied by pulsed field gel electrophoresis (PFGE)

The clonal relationship among Salmonella enterica serotype Typhimurium isolates from selected pig production units in Denmark was investigated by the pulsed field gel electrophoresis (PFGE) typing method to determine environmental survival and spread of Salmonella in different herds. Thirty-four Typhimurium isolated during 1996-1998 from porcine faeces and environmental samples from three pig farms designated 1, 3 and 5 were characterised by PFGE using two restriction enzymes. Farm 5 supplied piglets to farm 1 and the herds were located close to each other. Results of PFGE analysis showed both intra- and inter-relationships, i.e. identical PFGE patterns among the faecal and environmental isolates from farm 1 and farm 5. All the isolates from farm 3 irrespective of the source showed identical PFGE patterns, but were different from samples from farms 1 and 5. This study indicates spread between farms and survival of a farm-specific clone. Furthermore, identical PFGE patterns of isolates from piglet supplier and finisher herds indicate that the farrow-to-grower herd of farm 5 was sub-clinically infected prior to delivery to farm 1 and thereby caused the transmission of Salmonella.

Comparison of antimicrobial resistance phenotypes and resistance genes in Enterococcus faecalis and Enterococcus faecium from humans in the community, broilers, and pigs in Denmark

Enterococcus faecalis and E. faecium isolated from humans in the community (98 and 65 isolates), broilers (126 and 122), and pigs (102 and 88) during 1998 were tested for susceptibility to 12 different antimicrobial agents and for the presence of selected genes encoding resistance using PCR. Furthermore, the presence of vancomycin resistant enterococci was examined in 38 human stool samples using selective enrichment. Widespread resistance to chloramphenicol, macrolides, kanamycin, streptomycin, and tetracycline was found among isolates from all three sources. All E. faecium isolates from humans and pigs were susceptible to avilamycin, whereas 35% of isolates from broilers were resistant. All E. faecium isolates from humans were susceptible to vancomycin, whereas 10% and 17% of isolates from broilers and pigs, respectively, were resistant. A vancomycin resistant E. faecium isolate was found in one of the 38 human fecal samples examined using selective enrichment. All vancomycin resistant isolates contained the vanA gene, all chloramphenicol resistant isolates the cat(pIP501) gene, and all five gentamicin resistant isolates the aac6-aph2 gene. Sixty-one (85%) of 72 erythromycin resistant E. faecalis examined and 57 (90%) of 63 erythromycin resistant E. faecium isolates examined contained ermB. Forty (91%) of the kanamycin resistant E. faecalis and 18 (72%) of the kanamycin resistant E. faecium isolates contained aphA3. The tet(M) gene was found in 95% of the tetracycline resistant E. faecalis and E. faecium isolates of human and animal origin, examined. tet(K) was not observed, whereas tet(L) was detected in 17% of tetracycline resistant E. faecalis isolates and in 16% of the E. faecium isolates. tet(O) was not detected in any of the isolates from pigs, but was observed in 38% of E. faecalis isolates from broilers, in two E. faecalis isolates from humans and in three E. faecium isolates from broilers. tet(S) was not detected among isolates from animals, but was observed in 31% of E. faecalis and one E. faecium isolate from humans. This study showed a frequent occurrence of antimicrobial resistance and the presence of selected resistance genes in E. faecalis and E. faecium isolated from humans, broilers and pigs. Differences in the occurrence of resistance and tetracycline resistance genes were observed among isolates from the different sources. However, similar resistance patterns and resistance genes were detected frequently indicating that transmission of resistant enterococci or resistance genes takes place between humans, broilers, and pigs.

Collaborative research: a community approach

Collaborative nursing research is an effective means to increase research productivity. The essentials of collaborative research are contribution, communication, commitment, consensus, compatibility, and a cohesive approach toward a positive outcome. The purpose of the demonstration project was to describe a collaborative process in one community, culminating in a research utilization study and development of nursing standards pertaining to an aggregate population of patients.

[Complications after spinal analgesia using three different spinal needles: Sprotee, Spinocan and Atraucan]

In this prospective, randomised study 197 patients aged below 40 years received spinal analgesia using one of the following needles: Sprotte G24, Spinocan G27 or Atraucan G26. The incidence of insufficient or failed analgesia and difficulties handling the needles were noted. Patients were interviewed within three weeks after anaesthesia so as to establish the incidence of postoperative complications including post-dural puncture headache (PDPH). Headache was noted in 63 patients of which 33 (16.8%) were of PDPH type. The Sprotte needle caused significantly fewer cases of PDPH (Sprotte: 8.1%; Spinocan: 19.7; Atraucan: 21.7%. p < 0.05). Furthermore a significantly lower incidence of insufficient analgesia was observed with the Sprotte needle (0% versus 12.1% with the Spinocan and 11.6% with the Atraucan, p < 0.05). In conclusion, the Sprotte needle had the best profile with respect to PDPH and successful analgesia. This confirms the importance of the needle tip design.

Extensive regulation compromises the extent to which DNA gyrase controls DNA supercoiling and growth rate of Escherichia coli

As DNA gyrase is the only enzyme to supercoil DNA actively, we address here the question of whether it does play the expected dominant role in controlling the level of DNA supercoiling and growth rate in Escherichia coli. We modulated the expression of DNA gyrase around its wild-type level, and measured the effect on plasmid supercoiling and growth rate. As both the activity and the transcription rate of DNA gyrase are sensitive to DNA supercoiling we distinguish two types of control (with control defined as the percentage change observed on a 1% modulation of a parameter). The first type of control, here named inherent control, quantifies the effect of a sustained modulation of the transcription rate of gyrase. At its wild-type expression level this inherent control exerted by DNA gyrase on growth rate was very low, i.e. c mu/gyrase = 0.05 - 0.00, as was the inherent control on DNA supercoiling, c aLK/gyrase = 0.2. The second type of control, here named global control, quantifies the effect of a change in gyrase activity whilst allowing the cell to respond by readjusting gyrase transcription. Both types of control are linked via the sensitivity of gyrase transcription to DNA supercoiling, as determined from the inherent control by gyrase of the gyrase promoter activity using a chromosomal gyrB:lacZ fusion. As expected, the latter control was negative, but small, i.e. c gyr promoter/gyrase=-0.3. The global control by gyrase of active linking number was 0.1. These results show that although gyrase is an essential enzyme it does not have a high control, on either growth rate or DNA supercoiling. Homeostatic regulation of physiological DNA structure appears to dominate. At low degrees of DNA supercoiling, the control by DNA gyrase and by the other topoisomerases is much stronger.

The need for a veterinary antibiotic policy

The international recognition of the 'stable to table' approach to food safety emphasises the need for appropriate and safe use of antibiotics in animal production. An appropriate use of antibiotics for food animals will preserve the long-term efficacy of existing antibiotics, support animal health and welfare and limit the risk of transfer of antibiotic resistance to humans. Furthermore, it may promote consumer confidence in the veterinary use of antibiotics. In advancing these arguments, the authors of this article argue that there is a need for a visible and operational policy for veterinary use of antibiotics, paying particular attention to the policies that are being developed in Denmark.

Relationships between bone mineral density, serum vitamin D metabolites and calcium:phosphorus intake in healthy perimenopausal women

OBJECTIVES

To determine the relationships between serum vitamin D metabolites, bone mass, and dietary calcium and phosphorus in a cohort of 510 healthy Danish perimenopausal women.

DESIGN

A population-based cross-sectional study.

SUBJECTS

A total of 510 healthy women aged 45-58 years, with amenorrhoea for 3-24 months. None of the women was using hormone replacement therapy.

MEASUREMENTS

Measurements of total bone mineral content and regional bone mineral density were performed by dual-energy X-ray absorptiometry. Analyses of serum levels of 25-OHD and 1,25-(OH)2D, intact PTH, ionized calcium and phosphate, as well as biochemical markers of bone turnover in blood and urine. Assessment of calcium and phosphorus intake using dietary records.

RESULTS

A consistent inverse relationship between serum 1,25-(OH)2D and bone mineral content/ density was found in whole-body mineral content (P = 0.001), spine (P = 0.005) and femoral neck (P<0.05). There was a positive relationship between levels of 1,25-(OH)2D and biochemical bone markers, indicating that high levels of 1,25-(OH)2D are accompanied by increased bone turnover. The dietary calcium:phosphorus ratio was inversely related to serum 1,25-(OH)2D (P = 0.04) and positively related to bone mineral density (P<0.0005). No relationships could be detected between levels of PTH, serum ionized calcium and phosphate, and serum vitamin D metabolites.

CONCLUSION

Within normal physiological range, elevated levels of 1,25-(OH)2D were associated with decreased bone mineral density and content, reduced calcium:phosphorus ratio in the diet and increased bone turnover.