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L B Jensen

Publications and source records attributed to L B Jensen.

At least 55 records · Page 3Linked to original sources
PubMed1998

Internal size variations in Tn1546-like elements due to the presence of IS1216V.

In this study, internal size variations in the VanA gene cluster Tn1546, encoding resistance to glycopeptides, is described. Studies of previously uncharacterized size variations of an internal region, encoding the vanX and vanY genes of Tn1546, revealed that these variations were due to the presence of the IS sequence, IS1216V. This IS sequence has previously been found integrated in Tn1546. Integration of the IS1216V element created both deletions and a duplication in a non-essential region of Tn1546. In several isolates, the entire vanY gene was deleted, proving that this gene is non-essential for vancomycin resistance.

Animals↗
PubMed1998

Detection of the satA gene and transferability of virginiamycin resistance in Enterococcus faecium from food-animals.

The satA gene encoding streptogramin A resistance was detected in virginiamycin-resistant Enterococcus faecium isolates from pigs and broilers. The satA gene was present in 22 of 89 (25%) virginiamycin-resistant E. faecium isolates. It was shown that the satA gene and other gene(s) encoding streptogramin resistance could be transferred between isogenic E. faecium strains at frequencies ranging from 2.3 x 10(-4) to 2.2 x 10(-3) transconjugants per donor.

Acetyltransferases↗
PubMed1998

Characterisation of integrons and antibiotic resistance genes in Danish multiresistant Salmonella enterica Typhimurium DT104.

The presence and genetic content of integrons was investigated in eight Salmonella enteritica Typhimurium DT104 isolates from different pig herds in Denmark. Two different integrons were identified using PCR and sequencing. Each of the integrons carried a single resistance cassette in addition to the sull and qacE delta 1 genes characteristic of integrons. The first integron encoded the ant (3")-1a gene that specified resistance to spectinomycin and streptomycin. The second contained the pse-1 beta-lactamase gene. All the multiresistant strains contained both integrons. The presence of these two integrons did not account for the total phenotypic resistance of all the isolates and does not exclude the presence of other mobile DNA elements.

Animals↗
PubMed1998

Vitamin D receptor alleles do not predict bone mineral density or bone loss in Danish perimenopausal women.

A BsmI restriction enzyme polymorphism in the vitamin D receptor (VDR) gene has been reported to be associated with bone mineral density (BMD) and bone turnover. However, findings in other studies suggest the presence of considerable interaction by race, body size, and environmental factors. Therefore, we VDR BsmI genotyped 200 healthy perimenopausal Danish white women (mean age 50.8 years, mean calcium intake 900 mg/day) in a comprehensive, longitudinal, community-based population study. Bone loss was assessed by dual-energy X-ray absorptiometry (DXA) using cross-calibrated Hologic QDR-1000W and QDR-2000 densitometers, with a mean follow-up period of 4 years (range 1-5 years). Despite a distribution of genotypes similar to that of other white populations (28% bb, 49% Bb, 23% BB), VDR genotypes were not associated with lumbar or femoral baseline BMD, subsequent bone loss rates, or biochemical markers of bone metabolism (bone-specific alkaline phosphatase, urinary hydroxyproline, and serum osteocalcin). Controlling for body size, calcium intake, and serum levels of 25-hydroxyvitamin D3 [25(OH)D3] did not alter this finding. The possible existence of a threshold effect was subsequently investigated by restricting analysis to women with low serum 25(OH)D3 levels or low calcium intake. VDR BsmI genotypes showed no significant impact on bone density or bone loss in healthy Danish early postmenopausal women, even when allowance was made for calcium intake, serum 25(OH)D3, and body size.

Absorptiometry, Photon↗
PubMed1998

Molecular analysis of diverse elements mediating VanA glycopeptide resistance in enterococci.

Differences were examined among 24 distinct elements mediating VanA-type glycopeptide resistance in enterococci isolated from hospital patients and non-human sources in the UK. The methods used included long-PCR restriction fragment length polymorphism (L-PCR RFLP) analysis and DNA hybridization. All elements had conserved vanRSHAX genes, but variation occurred upstream of vanR and downstream of vanX. Twenty-one VanA elements had significant alterations upstream of vanR in the transposition genes orf1 and orf2: either parts of these genes were absent or they were disrupted by IS1216V or IS3-like insertion sequences. Among VanA elements with alterations downstream of vanX, seven lacked vanY, one lacked both vanY and vanZ, and ten had copies of insertion sequence IS1216V between vanX and vanY. All VanA elements of group D (from geographically and temporally diverse enterococci) were characterized by the presence of an IS1216V/IS3-like/orf1 complex and a point mutation in vanX, both of which were absent from the other 23 groups of VanA elements. This finding is consistent with the dissemination of a stable resistance element. We conclude that L-PCR RFLP analysis, combined with DNA hybridization, merits further development for studying the evolution and epidemiology of VanA resistance elements in enterococci.

Animals↗
PubMed1998

Molecular analysis of Tn1546 in Enterococcus faecium isolated from animals and humans.

The internal areas and the position of integration of the glycopeptide resistance element Tn1546 were characterized by using PCR fragment length polymorphism, sequencing, and DNA hybridization techniques with 38 high-level vancomycin-resistant Enterococcus faecium isolates of human and animal origins from Europe and the United States. Only minor variations in the coding regions within Tn1546 were found, suggesting high genetic stability. The isolates originated from broilers (n = 5), a chicken (n = 1), a duck (n = 1), a turkey (n = 1), pigs (n = 8), a pony (n = 1), and humans (n = 23). A total of 13 different types were defined based on a single-nucleotide difference in the vanX gene, the presence of insertion sequences, and hybridization patterns. For some types more than one isolate were found. For type 1, 10 isolates of both human and animal origins were found. All were indistinguishable from the reference strain, BM4147. For type 2, 11 isolates of human and animal origins were found. Six human isolates from England were all of type 3. Two human isolates from the United States, indistinguishable from each other, were type 9. These results showed that vancomycin-resistant E. faecium of animal and human origins can contain indistinguishable genetic elements coding for vancomycin resistance, indicating either horizontal gene transfer between E. faecium organisms of human and animal origins or the existence of a common reservoir for glycopeptide resistance.

Animals↗
PubMed1997

Improving compliance with hormonal replacement therapy in primary osteoporosis prevention.

OBJECTIVES: To evaluate whether introduction of treatment alternatives would improve compliance with hormonal replacement therapy (HRT) as primary osteoporosis prevention in women not tolerating the first line osteoporosis prevention schedule. MATERIAL AND METHODS: Follow-up in four hospitals participating in the Danish Osteoporosis Prevention Study. A total of 706 peri- and postmenopausal women aged 45-57 years between 3 and 24 months from last menstrual bleeding took part, 489 women were randomised to HRT and 217 received HRT by personal choice. A total of 135 (19%) women were hysterectomised. HRT was given as oral or transdermal oestradiol supplemented with progestogen. If the initial treatment allocation was not acceptable several alternatives were available in a pragmatic approach. RESULTS: Compliance with first treatment schedule was lower in women with intact uterus (at 5 years: 48.3 +/- 2.4% compliance) than in hysterectomised (64.7 +/- 5.8%, P < 0.001 in a Cox analysis) but did not differ after the introduction of HRT alternatives (67.0 +/- 2.9 vs 77.8 +/- 5.9, P = 0.12). Compliance decreased with increasing age at treatment start (RR = 1.11, P < 0.001) in women with intact uterus but not in hysterectomised women (P = 0.96). Headache/migraine was more frequent among women with intact uterus on oral sequential oestrogen plus progestogen than among hysterectomised women receiving oral continuous oestrogen (RR = 11.3, P < 0.01). CONCLUSIONS: It seems possible to maintain a high HRT compliance by a pragmatic approach including offering alternative HRT formulations to women not tolerating the primary HRT. Further research into long-term compliance with HRT and cost-benefit is warranted.

Cohort Studies↗
PubMed1997

Characterisation of integrons and antibiotic resistance genes in Danish multiresistant Salmonella enterica Typhimurium DT104.

The presence and genetic content of integrons was investigated in eight Salmonella enterica Typhimurium DT104 isolates from different pig herds in Denmark. Two different integrons were identified using PCR and sequencing. Each of the integrons carried a single resistance cassette in addition to the sul1 and qacE delta 1 genes characteristic of integrons. The first integron encoded the ant (3")-Ia gene that specified resistance to spectinomycin and streptomycin. The second contained the pse-1 beta-lactamase gene. All the multiresistant strains contained both integrons. The presence of these two integrons did not account for the total phenotypic resistance of all the isolates and does not exclude the presence of other mobile DNA elements.

Animals↗
PubMed1997

Chromosomal insertion of the entire Escherichia coli lactose operon, into two strains of Pseudomonas, using a modified mini-Tn5 delivery system.

A 12-kb PstI fragment including the entire E. coli lactose operon (lacIPOZYA) was inserted in one copy into the chromosome of Pseudomonas putida, Pseudomonas fluorescens and an E. coli strain with lac- phenotype. This was made possible by improvements of an already existing mini-Tn5 transposon delivery system (de Lorenzo et al., 1990; Herrero et al., 1990), which integrates cloned DNA fragments at random sites on the chromosome of the recipient bacteria in single copies. This has resulted in: (a) the making of two useful low copy-number cloning vectors both with extensive multi-cloning regions flanked by NotI sites needed in the mini-Tn5 delivery system; (b) the generation of E. coli nonlysogenic strains expressing the pi protein thus being capable of maintaining and delivering R6K-based mini-Tn5 vectors to other E. coli strains; (c) the successful insertion of the E. coli lactose operon into the P. fluorescens chromosome giving P. fluorescens the ability to grow on lactose; (d) evidence from Southern blotting that contradicts the assumption that the mini-Tn5 delivery system always creates one-copy inserts. These improvements allow insertion of large DNA fragments encoding highly expressed proteins into the chromosome of a large variety of Gram-negative bacteria including E. coli.

Chromosomes, Bacterial↗
PubMed1997

[Postoperative nausea and vomiting].

Postoperative nausea and vomiting (PONV) is still a problem and is very discomforting for the patients. As surgery done on out-patient basis becomes more frequent, PONV will represent an important factor in the length of recovery room stay, and is in this way an economic problem. Based on the literature from 1985-1995 factors associated with increased risk, prevention and treatment of PONV are discussed in view of the physiological mechanisms. The conclusion is that PONV is a complex problem. It demands an individual evaluation with a careful preoperative visit including planning of both preanaesthetic and anaesthetic agents. Furthermore, a proper anaesthetic treatment of the per- and postoperative course is of high importance. Patients at high risk of PONV should be identified and given prophylactic antiemetics.

Anesthetics↗
PubMed1997

Bone mass and risk factors for bone loss in perimenopausal Danish women.

OBJECTIVES: To determine risk factors for low bone mass at menopause and risk factors for subsequent bone loss in the following period. DESIGN: A cross-sectional study and a 2-year prospective follow-up. SETTING: The catchment area of Sundby Hospital in Copenhagen. SUBJECTS: Four hundred and thirty-three women aged 45-58 years, with amenorrhea for 3-24 months, of whom 87 were followed for a 2-year period. MEASUREMENTS: Registration of life-style and anthropometric variables, reproductive history, and family history of fractures. Total body bone mineral content (BMC) was measured with dual energy X-ray absorptiometry. RESULTS: By means of multiple regression analysis height, body weight, and length of reproductive period were found to be positively related to whole body BMC (P < 0.001), whilst a negative relationship was found to age (P < 0.001), smoking (P < 0.001), and family history of fractures (P < 0.005). In the longitudinal study, only body weight at the inclusion (P = 0.005) and subsequent changes in body weight and fat mass (P < 0.001) were related to the changes in bone mass. CONCLUSION: The most significant predictors for bone loss were changes in body weight and fat mass. Hence, weight loss is a risk factor for bone loss in the early postmenopausal period, whereas weight gain seems to preserve bone.

Body Weight↗
PubMed1997

Studies of the impact of a liver glucokinase promoter variant on glucose tolerance and insulin sensitivity index.

Because a frequently occurring nucleotide substitution at position -258 in the liver glucokinase promoter has been reported to be associated with impaired promoter activity, we have examined in Danish Caucasians whether this variant is associated with alterations in glucose tolerance and/or the insulin sensitivity index (Si). Among 246 Danish Caucasian patients with noninsulin-dependent diabetes mellitus, the allelic frequency of the -258 promoter variant was 15.2% (95% confidence interval: 12.0-18.4%) vs. 16.5% (13.2-19.8%) among 242 matched control subjects. In the control group, the glucokinase variant was not related to serum insulin or plasma glucose levels before or during an oral glucose tolerance test. Neither was the gene variant among 380 young, healthy subjects associated with altered Si or altered insulin secretion after an i.v. glucose load. We conclude that in Danish Caucasians, the -258 glucokinase promoter variant has no impact on glucose tolerance, whole-body Si, or insulin secretion.

Adult↗
PubMed1997

Site of osteodensitometry in perimenopausal women: correlation and limits of agreement between anatomic regions.

Because the bone mineral density (BMD) in different anatomic regions is heterogenous the number of women who fulfill the World Health Organization definition of osteopenia or osteoporosis increases with the number of regions examined. The purpose of this study was to investigate the agreement between measurements of the spine, femur, forearm, and whole body following menopause. Two thousand and five healthy, perimenopausal women, mean age 50.6 years, were studied using Hologic QDR-1000/W and QDR-2000 densitometers. Though the BMD of different anatomic regions were correlated (r = 0.40-0.77, p < 0.01), the variability in each patient regarding T and Z scores between regions was considerable. For example, despite a high correlation (r = 0.67, p < 0.01) and no systematic difference between the T scores for total femoral and lumbar BMD, the limits of agreement (mean difference +/- 2 SD) for the comparison were -1.89 to 1.87. Femoral neck T scores were 0.5 SD lower than those of the other regions, confirming reports that the young adult reference for this measurement is disproportionally high. The prevalence of osteoporosis was 1.2% when femur total BMD was considered alone and 5.9% when lumbar and ultradistal forearm results were included. However, as many as 7.9% showed osteoporosis of the femoral neck when the Hologic T score was used, compared with 0.7% using National Health and Nutrition Examination Survey (NHANES) values. The choice of anatomic region and availability of appropriate young adult reference data has considerable impact on the apparent prevalence of osteoporosis. Given the heterogeneity between regions, a combination of spinal and femoral densitometry should be used in diagnosing osteoporosis, though this increases the prevalence of osteoporosis by 50% or more in perimenopausal women.

Absorptiometry, Photon↗
PubMed1996

[Mammographic screening in the municipality of Copenhagen. Results of the first screening round].

The aim of the study was to evaluate the results from the prevalence round of the mammography screening programme in the Municipality of Copenhagen. All women who by 1 April 1991 were 50-69 years old, and who lived in the Municipality of Copenhagen, were during the period 1 April 1991-24 April 1993 offered a mammography. Those with suspect findings were recalled for further examination and possible biopsy. Women with breast cancer were offered treatment according to the standard national protocols (DBCCG). The participation rate was 71% (30,416/43,087). Among these 2043 (6.7%) were re-examined and 592 (1.9%) underwent surgical biopsy. Breast cancer was revealed in 359 (1.2%) women, of whom 88% had an invasive breast cancer. Prevalence of breast cancer increased significantly with increasing age. The positive predictive value for breast cancer among those re-examined was 18% and for those who had a surgical biopsy 61%. Among women with an invasive breast cancer 41% had a tumour of 10 mm or less, 80% had negative lymph node status and 56% had breast conserving surgery. During the following 12 months 14 women with a normal mammogram at the screening round developed breast cancer giving a sensitivity of 96%. It is concluded that the first mammography screening in Denmark showed the highest breast cancer prevalence published so far. A possible explanation could be a high sensitivity of the screening method, indicated by a relatively high frequency of small cancers. The screening programme was fully comparable with international standards.

Aged↗