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Biomedical subjects

J Dahl

Publications and source records attributed to J Dahl.

At least 19 recordsLinked to original sources
PubMed2006

Planned vaginal births in women with multiple sclerosis: delivery and birth outcome.

OBJECTIVE: The objective of this study was to investigate the effect of maternal multiple sclerosis (MS) on delivery and birth outcome in births without planned caesarean section. METHODS: Data were collected from the compulsory Medical Birth Registry of Norway from 1988 to 2002. Intended vaginal births in this time period were 449 births given by MS mothers and 851,060 control births. RESULTS: The MS mothers had a higher rate of induction of labour, and there was a strong trend for slower progression of second stage of labour and increased use of forceps. The MS group had lower birth weight and length of the neonates. The frequency of birth defects and the neonatal mortality were not increased in the MS group. CONCLUSIONS: Maternal MS affects the birth process and the neonate prenatally, even when the births with planned caesarean section are excluded. MS-related neuronal dysfunction linked to the uterus, is postulated as the most likely mechanism.

Body Size↗
PubMed2005

Pregnancy, delivery, and birth outcome in women with multiple sclerosis.

Using data from the compulsory Medical Birth Registry of Norway, the authors investigated the effect of maternal multiple sclerosis (MS) on pregnancy, delivery, and birth outcome in 649 births by MS mothers and 2.1 million control births. The mothers with MS had a higher proportion of neonates small for gestational age and also more frequent induction and operative interventions during delivery.

Age Distribution↗
PubMed2004

The correlation between Salmonella serology and isolation of Salmonella in Danish pigs at slaughter.

In Denmark, a serological Salmonella surveillance programme in finishing pig herds has been in place since 1995. The programme was founded on data from experimental studies, which demonstrated a strong association between Salmonella serology and the prevalence of these bacteria. The current study was carried out in three Danish abattoirs to evaluate the correlation under field conditions. A total of 160 Danish finishing pig herds were included. Seven out of these were examined twice, yielding a total of 167 observations. The herds were selected according to their herd serology based on data from the national surveillance. From each herd, samples were taken from 10 finishers at slaughter. The prevalence of Salmonella bacteria was measured at four sites: (1) caecal-content; (2) carcass surface; (3) pharynx; and (4) caecal lymph nodes. A logistic regression model was constructed for each sampling site. Abattoir, sanitary slaughter and herd seroprevalence were used as explanatory variables. The results demonstrated that there was a strong association between herd serology and the prevalence of Salmonella bacteria measured at three of the sampling sites: caecal-content, pharynx, and carcass surface. For these sites, the odds for being culture-positive for Salmonella varied from 1.3 to 1.5 for each increase of 10% in herd serology (P < 0.0001). For caecal lymph nodes, however, no linear association was found.

Animals↗
PubMed2004

Herd-level risk factors for subclinical Salmonella infection in European finishing-pig herds.

Our objective was to find herd factors associated with pigs testing seropositive for Salmonella. Data were collected from 359 finishing-pig herds in Germany, Denmark, Greece, The Netherlands and Sweden, between 1996 and 1998. Pigs fed non-pelleted feed (dry or wet) had 2- and 2.5-times lower odds of seropositivity, compared to pigs fed pelleted feed. The protective effect of non-pelleted feed over pelleted feed may be ascribed to the structure and composition. Also, pigs that were given whey (to drink or as the liquid part of the diet) had 2.6-times lower odds to test seropositive than pigs not getting whey. Pigs produced in batches in herds with hygienic-lock facilities had >3-times lower odds for testing seropositive compared to pigs in herds where only one or neither factor was present. In herds where the caretaker(s) washed hands consistently before tending to the animals, pigs had 1.5-times lower odds of seropositivity than pigs in herds where the caretaker did not. Pigs which were able to have snout contact with pigs in neighbouring pens (because pen separations were either open or too low) had 1.7-times higher odds to test seropositive compared to pigs for which such contact was prevented. Pigs in herds recruiting from more than three supplier herds had three-times higher odds to test seropositive than pigs in herds which breed their own replacement stock or recruit from a maximum of three supplier herds.

Animal Feed↗
PubMed2004

A European longitudinal study in Salmonella seronegative- and seropositive-classified finishing pig herds.

Surveillance and control are important aspects of food safety assurance strategies at the pre-harvest level of pork production. Prior to implementation of a Salmonella surveillance and control programme, it is important to have knowledge on the dynamics and epidemiology of Salmonella infections in pig herds. For this purpose, 17 finishing pig herds initially classified as seropositive and 15 as seronegative, were followed for a 2-year period through serological and bacteriological sampling. The study included 10 herds from Denmark, 13 from The Netherlands, 4 from Germany and 5 from Sweden and was performed between October 1996 and May 1999. The Salmonella status of finishing pig herds was determined by an initial blood sampling of approximately 50 finishing pigs close to market weight per herd. The development of the Salmonella status of the selected herds was assessed at seven subsequent sampling rounds of 25 blood samples from finishing pigs, 25 blood samples from grower pigs and 10 pen faecal samples each, approximately 3 months apart. The odds for testing finishers seropositive, given that growers were found seropositive previously were 10 times higher than if growers were seronegative (OR 10.0, 95% CI 3.2-32.8). When Salmonella was isolated from pen faecal samples, the herd was more likely to be classified seropositive in the same sampling round, compared to no Salmonella being detected (OR 4.0, 95% CI 1.1-14.6). The stability of an initially allocated Salmonella status was found to vary noticeably with time, apparently irrespective of a seropositive or seronegative classification at onset of the study. Given the measured dynamics in the occurrence of Salmonella in pig herds, regular testing is necessary to enable producers, advisors and authorities to react to sudden increases in the Salmonella prevalence in single herds or at a national level.

Animals↗
PubMed2003

Recovery of Salmonella enterica from seropositive finishing pig herds.

The aim of this study was to assess the probability of detecting Salmonella from pen faecal samples in seropositive classified finishing pig herds. The study involved 77 herds from Denmark (20), The Netherlands (20), Greece (17) and Germany (20). The serological herd status was determined by the blood-sampling of 50 finishing pigs. Bacteriological sampling was performed by 20 pen faecal samples per herd. Over-all, 47% of the blood samples had an OD% larger than 10 and 23% larger than 40. Salmonella was isolated from 135 (9.3%) pen faecal samples in 32 herds (42%). Twenty-eight of these herds (87.5%) had a within-herd seroprevalence larger than 50% at sample cut-off OD% > 10. In our study, there was an increasing probability of recovering Salmonella with increasing within-herd seroprevalence. However, this was only a moderate correlation. A correlation coefficient of 0.62 was found between the proportion of culture positive- and seropositive samples in a herd at cut-off OD%> 10 and of 0.58 at cut-off OD% > 40. Serology is a measure of historical exposure, which may or may not correlate closely to the microbiological burden at the time of sampling. Due to the low sensitivity of culture methods, apparent 'false-positive' serological results may well represent real infections not detected by bacteriological testing. For screening purposes, serological testing provides an indication of exposure to Salmonella, which forms the basis for targeted sampling, intervention and logistic slaughter procedures.

Animals↗
PubMed2000

The effects of an advanced practice nurse-directed heart failure program.

A study was conducted to determine if an inpatient heart failure program directed by an advanced practice nurse (APN) affects the following patient outcomes: length of hospital stay, mortality, readmission rates, and adherence to the recommended clinical regimen. Evaluating APN-directed heart failure programs may assist hospitals and clinics to determine whether such programs should be replaced, modified, continued, or replicated. For those facilities that are considering beginning a heart failure program, the data provided in this study may help establish the necessity of developing such a program or provide ideas for program design. The APN has an integral role in program design and can assist in achieving positive patient outcomes.

Aged↗
PubMed2000

Accelerated development of polyoma tumors and embryonic lethality: different effects of p53 loss on related mouse backgrounds.

Molecular evidence linking polyoma virus to p53 inactivation is thus far lacking, setting this highly oncogenic virus apart from other DNA tumor viruses. As a biological test for interaction, we studied the effects of p53 loss on development of virus-induced tumors. The absence of p53 led to more rapid tumor development on two different mouse backgrounds, indicating synergism between p53 loss and oncogenic pathways controlled directly by the virus. No effects of p53 on tumor type or frequency were noted. Polyoma tumor-derived cells in culture retained p53, and most of these showed induction of p21CIP1/WAF1 in response to DNA damage. These results indicate that p53 functions are not directly and fully impaired by the virus in the intact host. On one mouse background, it was discovered that loss of p53 resulted in complete embryonic lethality prior to 11 days of gestation. This lethality could be rescued by inclusion of gene(s) from a 129/SvJ background.

Animals↗
PubMed1999

Evaluation of a local cooperative project to improve postoperative pain management in Wisconsin hospitals.

The effectiveness of a local collaborative quality improvement project in improving the management of postoperative pain for Wisconsin Medicare patients was assessed. Six quality indicators were evaluated on the basis of baseline data from 714 subjects at 15 collaborating hospitals and follow-up data from 406 subjects from the same 15 hospitals. After efforts to improve postoperative pain management, there was statistically significant improvement in all six quality indicators.

Aged↗
PubMed1998

Effects of a cognitive-behavioral pain-management program.

A cognitive behavioral multidisciplinary pain management program was evaluated in two separate outcome studies; one controlled study (study I) and one study conducted on a consecutive sample with a long-term follow-up (study II). The 4-week inpatient treatment program included education sessions, goal setting, graded activity training, pacing, applied relaxation, cognitive techniques, social skills training, drug reduction methods, contingency management of pain behaviors, and planning of work return. The outcome of study I showed significant between-group differences in favor of the treatment group on measures of occupational training at 1-month follow-up, activity level in the sparetime at post-treatment and at follow-up, and decreased catastrophizing and pain behaviors at post-treatment. In study II significant improvements over time were found on measures of sick leave, pain intensity, pain interference, life control, affective distress, activity level in the sparetime, physical fitness and use of analgetics at 2-month follow-up and at 1-year follow-up. The results of the two outcome studies reported show that cognitive behavioral multidisciplinary pain management programs can successfully be applied to Swedish musculoskeletal pain patients.

Adaptation, Psychological↗
PubMed1998

Evidence of a role for phosphatidylinositol 3-kinase activation in the blocking of apoptosis by polyomavirus middle T antigen.

A polyomavirus mutant (315YF) blocked in binding phosphatidylinositol 3-kinase (PI 3-kinase) has previously been shown to be partially deficient in transformation and to induce fewer tumors and with a significant delay compared to wild-type virus. The role of polyomavirus middle T antigen-activated PI 3-kinase in apoptosis was investigated as a possible cause of this behavior. When grown in medium containing 1D-3-deoxy-3-fluoro-myo-inositol to block formation of 3'-phosphorylated phosphatidylinositols, F111 rat fibroblasts transformed by wild-type polyomavirus (PyF), but not normal F111 cells, showed a marked loss of viability with evidence of apoptosis. Similarly, treatment with wortmannin, an inhibitor of PI 3-kinase, stimulated apoptosis in PyF cells but not in normal cells. Activation of Akt, a serine/threonine kinase whose activity has been correlated with regulation of apoptosis, was roughly twofold higher in F111 cells transformed by either wild-type virus or mutant 250YS blocked in binding Shc compared to cells transformed by mutant 315YF. In the same cells, levels of apoptosis were inversely correlated with Akt activity. Apoptosis induced by serum withdrawal in Rat-1 cells expressing a temperature-sensitive p53 was shown to be at least partially p53 independent. Expression of either wild-type or 250YS middle T antigen inhibited apoptosis in serum-starved Rat-1 cells at both permissive and restrictive temperatures for p53. Mutant 315YF middle T antigen was partially defective for inhibition of apoptosis in these cells. The results indicate that unlike other DNA tumor viruses which block apoptosis by inactivation of p53, polyomavirus achieves protection from apoptotic death through a middle T antigen-PI 3-kinase-Akt pathway that is at least partially p53 independent.

Androstadienes↗
PubMed1997

Elimination of Salmonella typhimurium infection by the strategic movement of pigs.

Three field investigations were carried out to assess the feasibility of raising salmonella-free finishers from pigs born in infected herds, by moving the pigs to clean and disinfected facilities before their expected exposure to the bacteria from the environment. Three herds with persistently high levels of subclinical infection with S typhimurium in the finishing pigs were used. They practised all-in all-out management in the nurseries and in the grower units. A total of 844 pigs were moved, either at weaning, from the nursery, or from the grower unit to newly built or rigorously cleaned and disinfected finishing units with no known history of salmonella infection. No detectable infection was observed at slaughter either serologically or bacteriologically by random testing of the pigs which had been moved, whereas a proportion of the pigs raised at the same time in the continuous systems on the farms were found to be infected.

Animal Husbandry↗
PubMed1997

Effects of exercise on fatigue, aerobic fitness, and disease activity measures in persons with rheumatoid arthritis.

The effects of 12 weeks of low-impact aerobic exercise on fatigue, aerobic fitness, and disease activity were examined in a quasi-experimental time series study of 25 adults with rheumatoid arthritis (RA). Measures were obtained preintervention, midtreatment (after 6 weeks of exercise), end of treatment (after 12 weeks of exercise), and at a 15-week follow-up. ANOVAS for repeated measures showed that those subjects who participated more frequently reported decreased fatigue, while those who participated less frequently reported an increase in fatigue. All subjects, on average, showed increased aerobic fitness and increased right and left hand grip strength, decreased pain, and decreased walk time. There were no significant increases in joint count or sedimentation rate. Significant improvements in measures at the 15-week follow-up also were found. Findings indicate that persons with RA who participate in appropriate exercises may lessen fatigue levels and experience other positive effects without worsening their arthritis.

Adult↗
PubMed1996

Studies of partially transforming polyomavirus mutants establish a role for phosphatidylinositol 3-kinase in activation of pp70 S6 kinase.

Infection of mouse fibroblasts by wild-type polyomavirus results in increased phosphorylation of ribosomal protein S6 (D.A. Talmage, J. Blenis, and T.L. Benjamin, Mol. Cell. Biol. 8:2309-2315, 1988). Here we identify pp70 S6 kinase (pp70S6K) as a target for signal transduction events leading from polyomavirus middle tumor antigen (mT). Two partially transforming virus mutants altered in different mT signalling pathways have been studied to elucidate the pathway leading to S6 phosphorylation. An upstream role for mT-phosphatidylinositol 3-kinase (PI3K) complexes in pp70S6K activation is implicated by the failure of 315YF, a mutant unable to promote PI3K binding, to elicit a response. This conclusion is supported by studies using wortmannin, a known inhibitor of PI3K. In contrast, stable interaction of mT with Shc, a protein thought to be involved upstream of Ras, is dispensable for pp70S6K activation. 250YS, a mutant mT which retains a binding site for PI3K but lacks one for Shc, stimulates pp70S6K to wild-type levels. Mutants 315YF and 250YS induce partial transformation of rats fibroblasts with distinct phenotypes, as judged from morphological and growth criteria. Neither mutant induces growth in soft agar, indicating that an increase in S6 phosphorylation, while necessary for cell cycle progression in normal mitogenesis, is not sufficient for anchorage-independent cell growth. In the polyomavirus systems, the latter requires integration of signals from mT involving both Shc and PI3K.

3T3 Cells↗
PubMed1995

Phosphatidylinositol 3-kinase binding to polyoma virus middle tumor antigen mediates elevation of glucose transport by increasing translocation of the GLUT1 transporter.

Elevation in the rate of glucose transport in polyoma virus-infected mouse fibroblasts was dependent upon phosphatidylinositol 3-kinase (PI 3-kinase; EC 2.7.1.137) binding to complexes of middle tumor antigen (middle T) and pp60c-src. Wild-type polyoma virus infection led to a 3-fold increase in the rate of 2-deoxyglucose (2DG) uptake, whereas a weakly transforming polyoma virus mutant that encodes a middle T capable of activating pp60c-src but unable to promote binding of PI 3-kinase induced little or no change in the rate of 2DG transport. Another transformation-defective mutant encoding a middle T that retains functional binding of both pp60c-src and PI 3-kinase but is incapable of binding Shc (a protein involved in activation of Ras) induced 2DG transport to wild-type levels. Wortmannin (< or = 100 nM), a known inhibitor of PI 3-kinase, blocked elevation of glucose transport in wild-type virus-infected cells. In contrast to serum stimulation, which led to increased levels of glucose transporter 1 (GLUT1) RNA and protein, wild-type virus infection induced no significant change in levels of either GLUT1 RNA or protein. Nevertheless, virus-infected cells did show increases in GLUT1 protein in plasma membranes. These results point to a posttranslational mechanism in the elevation of glucose transport by polyoma virus middle T involving activation of PI 3-kinase and translocation of GLUT1.

Amino Acid Sequence↗
PubMed1993

Synthesis and evaluation of 3-modified 1D-myo-inositols as inhibitors and substrates of phosphatidylinositol synthase and inhibitors of myo-inositol uptake by cells.

A number of 3-substituted 1D-myo-inositols were synthesized and evaluated as substrates for phosphatidylinositol synthase and uptake by intact cells. 1D-3-Amino-, -3-chloro-, and -3-(acetylthio)-3-deoxy-myo-inositols were all synthesized by nucleophilic displacement of the 6-O-(trifluoromethyl)sulfonyl group of 1L-1,2:3,4-di-O-cyclohexylidene-5-O-methyl-6-O-[(trifluoromethyl)-sulfon yl] - chiro-inositol (which was prepared from L-quebrachitol), respectively, by reaction with LiN3, followed by reduction of the azido function, and with LiCl and KSAc to give the O-protected compounds. O-Demethylation using BBr3 and concomitant acetal hydrolysis furnished the free-hydroxy 3-amino- and 3-chloro-3-deoxy-1D-myo-inositols. The 3-mercapto analogue was obtained by removal of the acetal groups of the acetylthio analogue, followed by acetylation and purification of the peracetate, and subsequent O-demethylation and deacetylation. The 3-deoxy derivative was synthesized from the 6-O-(imidazol-1-ylthiocarbonyl) compound via Barton-McCombie deoxygenation. The 3-azido derivative was directly synthesized from 1L-1-O-tosyl-chiro-inositol via displacement with azide. The 3-keto analogue was prepared by Pt-catalyzed air oxidation of 1L-chiro-inositol. The compounds were all evaluated as substrates for phosphatidylinositol (PtdIns) synthase from mouse brain. The 3-NH2, 3-F, 3-deoxy, and 3-keto analogues all showed activity as substrates, as measured by liberation of cytidine monophosphate. These compounds also showed inhibition of the reaction of myo-[3H]inositol with PtdIns synthase. These results taken together indicate that these compounds are likely to be incorporated into phospholipids. As a further indication that these compounds might be useful as probes for the PtdIns pathway, it was demonstrated that the 3-NH2, 3-F, and 3-deoxy compounds are taken up by intact fibroblast cells as evidenced by their competing with myo-[3H]inositol uptake.

Acetates↗