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B Pedersen

Publications and source records attributed to B Pedersen.

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

5q(-)survival: importance of gender and deleted 5q bands and survival analysis based on 324 published cases.

Survival of 5q(-)patients is known to depend on patient age, diagnosis, and acquisition of additional chromosome aberrations. The possible importance of the deleted 5q bands is unknown; nor is it known if the same or different factors are of prognostic importance in 5q(-)MDS and 5q(-)AML. In order to obtain material of sufficient size to answer these and other questions the literature was searched for 5q(-)cases with data on survival. Only MDS and AML cases with interstitial deletions were included. The results confirmed the prognostic importance of the factors mentioned above, but produced the following new data: In MDS, but not in AML, loss of the band 5q12 is an independent adverse prognostic factor; female patients survive longer in MDS while in AML men are the longer survivors; del(5)(q13q31) was found to be associated with MDS, 5q(-)as the sole aberration, and a long survival; on the other hand many del(5)(q12q32) cases showed AML, presence of additional aberrations, and short survivals. On the basis of these results the following hypotheses are proposed: 1) the female preponderance in 5q(-)MDS is due to longer female survival, and not to increased female incidence, and 2) some 5q deletions have a high diagnostic specificity, affect the rate of development of additional chromosome aberrations and thus in fact are major prognostic factors.

Chromosomes, Human, Pair 5↗
PubMed1998

Combination laser conization as treatment of microinvasive carcinoma of the uterine cervix.

During the period June 1985 to August 1992 combination laser conization was considered definite therapy in 41 patients with microinvasive carcinoma of the cervix. Selection criteria for conservative, fertility-saving therapy were: invasion 3 mm or less, no lymphovascular involvement and horizontal spread of 7 mm or less. After treatment patients were followed for 5 to 12 years, mean follow-up 81 months, and mean number of examination was 10. In one cases, adenocarcinoma in situ was diagnosed during follow-up. In all other cases persistent or recurrent disease was not diagnosed during follow-up. By thorough histopathologic evaluation and strict criteria for selection of patients, it was possible to perform conservative treatment with no observed risk of undertreatment. Combination laser conization was a useful treatment modality. A follow-up regimen based on colposcopy and cytology proved sufficient.

Adolescent↗
PubMed1997

MDS and AML with trisomy 8 as the sole chromosome aberration show different sex ratios and prognostic profiles: a study of 115 published cases.

A number of chromosome aberrations occur nonrandomly as the sole aberration in malignant and premalignant hematological disorders. They imply very different prognoses. For most of them the survival consequences have been established. For trisomy 8, which is the most frequent numerical aberration in myeloid disorders, the prognostic implications have not been investigated. In order to clarify survival in patients with trisomy 8 as the sole aberration, the literature was searched for such cases. In 115 patients survival data were available. In 103 (89.6%), a myeloid disorder had been diagnosed. Acute myeloid leukemia (AML) or a myelodysplastic syndrome (MDS) occurred in 100 cases (87.0%). The median survival was found to be 17.1 months. On multivariate survival analysis (Cox), age above 60 and a leukemic diagnosis were found to be independent adverse prognostic indicators. MDS patients survived significantly longer (median 21 months) than AML patients (median 15 months). In MDS age and in AML the trisomy 8 clonal size was an independent prognostic factor. An unexpected observation was a clear male preponderance in trisomy 8 MDS (about two-thirds of cases). In trisomy 8 AML an approximate 1:1 ratio was found. Browsing of Mitelman's catalog confirmed these ratios.

Adolescent↗
PubMed1997

The monosomy 7 clone in interphase and metaphase cell population: a combined chromosome and primed in situ labeling study.

Loss of a chromosome 7 is associated with a poor prognosis in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). Some studies have shown higher frequencies of monosomy 7 (-7) in dividing than nondividing myeloid cells, which might indicate that -7 confers a proliferative advantage on the host cell. As other groups have not been able to confirm this, we compared the -7 frequencies in bone marrow metaphases as studied with conventional cytogenetics and in interphase cells using primed in situ (PRINS) labeling. We found significantly higher -7 frequencies in metaphase than in interphase cells irrespective of diagnosis and presence or absence of additional chromosome aberrations. Further, we found a significant correlation between the -7 percentages in resting and dividing cells. Finally, as our material showed a clear male preponderance, Mitelman's Catalog of Chromosome Aberrations in Cancer was searched for -7. Of 815 cases with AML or MDS, 491 (60.3%) were found to be men. To our knowledge, this is the first observation of a clear deviation from the 1:1 sex ratio in -7 patients.

Acute Disease↗
PubMed1997

Graphical interpretation of analytical data from comparison of a field method with reference method by use of difference plots.

Various viewpoints have been offered regarding the appropriate use of scatter plots or difference plots (bias plots or residual plots) in comparing analytical methods. In many of these discussions it seems the basic concepts of identity (within inherent imprecision) and acceptability based on analytical goals (analytical quality specifications) have been forgotten. With the increasing number of Reference Methods in laboratory medicine, these basic concepts are becoming more important in validation of field methods. Here we describe a simple and effective graphical test of these hypotheses (identity and acceptability) by use of difference plots. These plots display the underlying hypothesis before the measured differences are plotted and allow interpretation of the results according to specific criteria. We further describe simple but effective interpretations of the data, when the hypothesis is not fulfilled, by using two data sets drawn from comparisons of field methods for S-creatinine with a Reference Method for this analyte. The difference plot is a graphical tool with related simple statistics for comparison of a field method with a Reference Method, focusing on (a) identity within the inherent analytical imprecision or (b) acceptability within analytical quality specifications. Calculation of the standard deviation of the differences is an indispensable tool for evaluation of aberrant-sample bias (matrix effects).

Chemistry, Clinical↗
PubMed1996

[MR-scanning in complex partial epilepsy].

In a prospective investigation concerning 50 consecutive patients suffering from complex partial epilepsy who all had a normal CT investigation pathological findings were recognized in 80% using MRI. The MRI examination included volume estimation of the hippocampus. The volume estimations were compared to a reference material. In 24% a focal pathology was recognized, that was suspected of being responsible for the epileptic condition. Only 20% of the examinations were evaluated as normal. Hippocampal atrophy was recognized in 50%. In the latter group a diagnosis of hippocampal sclerosis was established in 16%. It is concluded that MRI is the investigation of choice in complex partial epilepsy and that volume estimation of the hippocampus is important.

Epilepsies, Partial↗
PubMed1996

The blood group ABO gene transcript is down-regulated in human bladder tumors and growth-stimulated urothelial cell lines.

The molecular mechanism that in human bladder tumors leads to the loss of blood group ABO glycosyltransferase activity and, thereby, the loss of ABO antigens was investigated. In 15 tumors and 3 normal biopsies from blood group AB individuals and 7 tumors and 3 normal biopsies from blood group O individuals, mRNA was detected by a reverse transcription PCR (RT-PCR) assay, and the ABO blood group structure was determined by immunohistology. The RT-PCR spanned several introns in the ABO gene to exclude DNA contamination, and the RT-PCR product was shown to reflect the ABO gene message by dideoxy sequencing. The ABO mRNA was present in normal urothelium and low-grade tumors but disappeared from high grade tumors. This correlation to tumor grade was significant (P<0.04). Immunohistochemistry with monoclonal anti-blood group antibodies showed a complete correlation between the presence of mRNA and the presence of AB carbohydrate structures on cell surfaces. In two urothelial cell lines, genotyped as A/- and A/A, growth stimulation with the cholera toxin B subunit led to a total loss of ABO mRNA, and epidermal growth factor stimulation had an identical effect on one of the cell lines. We conclude that the ABO glycosylation in normal and malignant urothelium is regulated at the mRNA level, and that a mechanism associated with cell proliferation may trigger down-regulation of ABO mRNA.

ABO Blood-Group System↗
PubMed1996

WHO-sponsored international collaborative study to evaluate methods for subtyping Listeria monocytogenes: restriction fragment length polymorphism (RFLP) analysis using ribotyping and Southern hybridization with two probes derived from L. monocytogenes chromosome.

Seven laboratories participated in a WHO-sponsored international collaborative study, to evaluate methods for subtyping Listeria monocytogenes, by performing restriction fragment length polymorph sm (RFLP) analysis-based subtyping of an international study set of 80 strains of L. monocytogenes that included 22 epidemiologically related groups. The RFLP analysis was done by Southern hybridization with one of two types of probes found in multiple copies on the chromosome of L. monocytogenes. Six laboratories performed ribotyping. These laboratories used EcoRI enzyme to restrict the L. monocytogenes DNA and ribosomal RNA or DNA as the probe for Southern hybridizations. The seventh laboratory used Ncil to restrict the DNA, and two probes, one randomly cloned and the other containing repeat sequences cloned from L. monocytogenes DNA. The overall discriminating power of ribotyping, as estimated by calculation of Simpson's index of diversity, ranged from 0.83 to 0.88 for the six laboratories. The discriminating power of the combination of two probes used by Laboratory 7 was 0.91. Ribotyping and the cloned probes used by Laboratory 7 discriminated poorly between serotype 4b strains. Neither method identified three atypical strains (identified by other subtyping methods) included in three apparently epidemiologically related groups. Ribotyping did not discriminate between strains of serotypes 4b and 4b(X) in one epidemiologically related group of strains; one cloned probe used by Laboratory 7 discriminated between these strains. Intra-laboratory reproducibilities for the seven laboratories ranged from 80.0 to 100%. as determined by their abilities to correctly identify 11 pairs of duplicate strains included in the study set. Inter-laboratory reproducibilities were generally very good considering that no attempt was made to standardize protocols used by the participants.

Bacterial Typing Techniques↗
PubMed1996

Relation of blast cell survival and proliferation to chemotherapy resistance in AML.

We have investigated the in vitro blast cell survival (viability) and drug resistance to cytosine arabinoside (Ara-C), daunorubicin (Dau), mitoxantrone (Mitox) and aclarubicin (Acla) of fresh leukaemic blast cells from 80 patients with newly diagnosed acute myeloid leukaemia (AML) employing the semiautomated colourimetric MTT(3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide)-assay. In 15 cases we concurrently investigated the relation between in vitro blast cell survival (MTT assay) and blast cell proliferation (3H-thymidine incorporation) in the presence and absence of myeloid growth factors (GFs) G-CSF, GM-CSF and IL-3 (individually and in combination). A highly significant correlation was found between blast cell survival and blast cell proliferation (r = 0.87, P < 1 x 10(-4). Furthermore, in 40 evaluable adult patients who completed intravenous induction chemotherapy and were evaluable for response to chemotherapy we found a positive correlation between in vitro blast survival (MTT assay) and response to chemotherapy with high blast survival being associated with poor response to chemotherapy (P = 0.05). Moreover, in a multivariate analysis, high blast cell survival was significantly associated with high CD13 expression and monocytic phenotype (P = 0.0003 and P = 0.02, respectively). Furthermore, we found an inverse relationship between the baseline proliferation of the blasts and the magnitude of response to the GFs (P < 0.02), indicating that cells with low baseline proliferation were more readily stimulated by growth factors. Finally, we found a significant correlation between leukaemic cell survival and cellular drug resistance towards Dau (P = 0.001) and Mitox (P = 0.03), but not towards Ara-C (P = 0.68) and Acla (P = 0.13). We conclude that high in vitro leukaemic cell survival is associated with drug resistance in vivo and in vitro, and furthermore is correlated with high blast cell proliferation and some adverse prognostic factors previously identified in AML.

Aclarubicin↗
PubMed1996

The effect of iron chelation on haemopoiesis in MDS patients with transfusional iron overload.

Long-term follow-up data are presented on changes in peripheral blood counts and Hb requirements of 11 patients with myelodysplastic syndromes (MDS) during iron chelation treatment with desferrioxamine for up to 60 months. The erythroid marrow activity was indirectly evaluated by repeated determinations of the serum transferrin receptor concentration. The efficacy of iron chelation was evaluated by repeated quantitative determination of the liver iron concentration by magnetic resonance imaging. Reduction in the Hb requirement ( > or = 50%) was seen in 7/11 (64%) patients. Five patients (46%) became blood transfusion independent. Platelet counts increased in 7/11 (64%) patients and the neutrophil counts in 7/9 (78%) evaluable patients. All patients in whom iron chelation was highly effective showed improvement of erythropoietic output accompanied by an increase in the serum transferrin receptor concentration. It is concluded that reduction in cytopenia in MDS patients may be accomplished by treatment with desferrioxamine, if the iron chelation is efficient and the patients are treated for a sufficiently long period of time. Exactly how treatment with desferrioxamine works remains a challenge for further investigation.

Adolescent↗
PubMed1996

Controlled trial of lamotrigine (Lamictal) for treatment-resistant partial seizures.

The antiepileptic effect of lamotrigine (Lamictal) was assessed in a double-blind, placebo-controlled, crossover trial in 56 adult patients with refractory partial seizures. Lamotrigine or placebo was added to the patients' existing antiepileptic drugs (AEDs). The dose of lamotrigine varied from 75 to 400 mg daily. Thirty-eight patients completed the trial and 7 withdrew because of adverse experiences. There was a statistically significant reduction in seizure counts on lamotrigine compared with placebo for total seizures (30.3% reduction, 95% CI 8.4%, 47.0%), complex partial seizures (29.2% reduction, 95% CI 3.8%, 47.9%) and secondary generalised seizures (37.9%, CI 18.9%, 52.4%). The analysis of total seizure days showed a similar significant reduction during lamotrigine treatment for the same seizure categories. There was no statistically significant difference in reporting of adverse events between lamotrigine and placebo except for dizziness which was reported more frequently on lamotrigine than on placebo. There were no differences in abnormal haematological or biochemical findings between lamotrigine and placebo, and lamotrigine had no effect on plasma concentrations of concomitant AEDs.

Adolescent↗
PubMed1996

Maternal HLA class II alleles predispose to pregnancy losses in Danish women with recurrent spontaneous abortions and their female relatives.

PROBLEM: If damage to the trophoblast mediated through autoimmune mechanisms is responsible for recurrent spontaneous abortions (RSA), maternal class II HLA antigens might be expected to be involved. We wanted to evaluate the impact of these antigens on pregnancy outcome in RSA women and their relatives. METHOD: HLA-DR and -DQ typing using RFLP and PCR-SSP methods was carried out in 234 Danish women with unexplained RSA and 360 controls. The HLA-DR types were correlated to outcome of the next pregnancy in 94 patients. Sisters, brothers, and wives of brothers of 146 consecutive patients were HLA typed and their pregnancy outcomes were correlated to the HLA-DR types. RESULTS: HLA-DR1/Br and -DR3 were each significantly increased in women with at least four previous pregnancy losses (both P-values < 0.05 after correction for multiple comparisons). In the prospective study, 62% of the HLA-DR1/Br and/or -DR3 positive patients miscarried the next pregnancy compared with only 29% of those negative for both allogenotypes (P = 0.025). The family studies indicated that female relatives of RSA patients had a greater risk (odds ratio = 5.0, 95% CI = 2.0-11.0) of pregnancy losses when positive for HLA-DR1/Br and/or -DR3 than those negative for the allogenotypes. CONCLUSIONS: Maternal HLA-DR allogenotypes DR1/Br and -DR3 or closely linked genes seem to predispose to pregnancy losses in RSA patients and their first degree relatives.

Abortion, Habitual↗
PubMed1996

Subcutaneous administration of hyaluronan reduces the number of infectious exacerbations in patients with chronic bronchitis.

Hyaluronan (HA) is a high molecular weight glycosaminoglycan found in large amounts in the skin, joints, and other organs. Previous studies have shown that HA stimulates neutrophil functions both in vitro and in vivo. The object of this study was to test the hypothesis that HA administration subcutaneously might reduce the number of bacterial infections in humans with an increased susceptibility to such infections. For this purpose we have studied 29 patients with chronic bronchitis and recurrent acute exacerbations of their disease. The patients were randomly separated into two groups. One group had HA for 6 mo followed by 6 mo of placebo, and the other group started with placebo treatment followed by HA. The treatment periods occurred during two consecutive winter periods. HA-treated patients had significantly fewer acute exacerbations (p = 0.01) than did placebo-treated patients. Likewise the consumption of antibiotics and other signs of bacterial infections were reduced. In the crossover study the placebo-treated patients again had much higher numbers of acute exacerbations than did the HA-treated patients (p < 0.0001). It is concluded that HA reduces the number of infectious exacerbations in patients with chronic bronchitis, possibly by enhancing cellular host defense mechanisms. HA is a new endogenous substance that can be used to stimulate host defense reactions and reduce the need of antibiotics. Before being recommended for clinical use, however, our results should be confirmed by further studies.

Aged↗
PubMed1996

Eosinophil and neutrophil activity in asthma in a one-year trial with inhaled budesonide. The impact of smoking.

The object of this investigation was to study the long-term effects of antiasthma treatment on blood markers of inflammation and lung function in adult asthmatic subjects. For this purpose 85 allergic and nonallergic asthmatic subjects were randomized into three groups, which were given high-dose (1,600 micrograms/d) inhaled budesonide, low-dose (400 micrograms/d) inhaled budesonide, and oral theophylline (600 mg/d), respectively, and were followed for 11 mo with testing of lung function and blood sampling for the assay in serum of eosinophil cationic protein (ECP), eosinophil protein x/eosinophil derived neurotoxin (EPX/EDN) as eosinophil markers, and myeloperoxidase (MPO) and lactoferrin (LF) as neutrophil markers. Lung functions (FEV1% predicted, and histamine PC20) and the eosinophil markers ECP and EPX/EDN were improved and reduced, respectively, by budesonide in a dose-dependent and temporally parallel fashion. Theophylline did not alter lung functions but reduced ECP and EPX/EDN after prolonged treatment. The treatment efficacy of budesonide was attributed solely to an effect on nonsmoking asthmatic subjects, since neither lung functions nor eosinophil markers changed in smokers even with high-dose budesonide. MPO but not LF was reduced after several months of treatment in all three groups, but only in nonsmokers. We conclude that ECP and EPX/EDN may be used to monitor antiinflammatory treatment in asthmatic patients, and that smoking asthmatic subjects are resistant to inhaled corticosteroids.

Adult↗
PubMed1996

Clonal chromosome aberrations in myeloid leukemia after styrene exposure.

OBJECTIVES: The purpose of the study was to determine the risk of myeloid leukemia subclassified according to clonal chromosome aberrations in styrene-exposed workers. METHODS: A nested case-referent study was carried out on 19 myeloid leukemia patients, of which 12 showed clonal chromosome aberrations, and 57 referents ascertained within the Danish reinforced plastics industry and similar industries with no styrene exposure. RESULTS: A 2.5-fold increased risk for myeloid leukemia with clonal chromosome aberrations (95% confidence interval 0.2-25.0) was found among workers of companies with styrene exposure. CONCLUSIONS: The results suggest that styrene may cause leukemia through a clastogenic effect. But similar findings could also have been found if the exposure was associated with a specific subtype of leukemia prone to develop the chromosome aberrations in question. Due to the few observations and the lack of detailed exposure data, additional studies are needed to corroborate or refute the present suggestive findings.

Adult↗
PubMed1996

Pig farmers have signs of bronchial inflammation and increased numbers of lymphocytes and neutrophils in BAL fluid.

The purpose of this study was to investigate whether pig farmers had inflammation of the bronchial mucosa and activation of bronchoalveolar lavage (BAL) cells. Pig farmers are exposed to high dust levels and have a prevalence of work-related respiratory symptoms. Bronchoscopy and BAL were performed in 27 young large-scale pig farmers, who had never smoked. Fifty three lifetime nonsmoking healthy students participated as controls. All farmers and controls had normal lung function (forced expiratory volume in one second (FEV1) 109 and 105% predicted respectively. Estimation of macroscopic signs of inflammation in the bronchi (erythema, oedema, secretion and friability) showed that pig farmers had significantly increased signs of inflammation. The median score was 3 (range 0-6) compared to a median score of 0 (range 0-3) in controls. More pig farmers than controls (41 versus 25%) had a positive histamine challenge (provocative dose producing a 20% fall in FEV1 (PC20) < or = 32 mg.mL-1) but the difference was not significant. The cell concentration in BAL fluid was identical in the two groups. Pig farmers had a significantly increased percentage of lymphocytes (median 7, range 1-27 versus median 2, range 0-7) and neutrophils (median 2, range 0-30 versus median 1, range 0-4) compared to controls. Spontaneous migration (19.8 versus 5.5 microns) and chemotaxis (62.6 versus 11.2 microns) was significantly increased in pig farmers compared to controls. After stimulation with zymosan and phorbol myristrate acetate (PMA), the reactive oxygen radical generation of purified alveolar macrophages was also significantly increased in pig farmers. Lifetime nonsmoking pig farmers with normal lung function have macroscopic signs of bronchial inflammation and an increased number of neutrophils in bronchoalveolar lavage. Their alveolar macrophages showed biological signs of activation. The inflammation of pig farmers bronchi may be early signs of bronchitis.

Adult↗