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Biomedical subjects

K Petersen

Publications and source records attributed to K Petersen.

At least 55 records · Page 3Linked to original sources
PubMed1997

Medical negligence and wrongful birth actions: Australian developments.

Wrongful birth actions aim to compensate litigants who are negligently deprived by health professionals of their right to reproductive choice. Access to safe and legal abortion is integral to the action and wrongful birth claims in the United Kingdom have been facilitated by the Abortion Act 1967 (as amended). The recent Australian case CES v Superclinics (1995) 38 NSWLR 47 shows how judicial confusion about the legality of abortion can result in judges condoning medical negligence. The Superclinics case also suggests that doctors are not required to provide pregnant women with the same standard of care as other patients. These developments show that law can become incoherent and health professionals can act negligently with impunity when reproductive choice does not have a secure legal foundation.

Abortion, Legal↗
PubMed1996

[Rhinoslceroma in an elderly Danish woman].

A case of rhinoscleroma in an elderly Danish woman is presented. The characteristics of the disease are described. An 84-year old female presented with serous rhinorrhoea, swelling of the columella and the upper lip and granulomatous masses in the right inferior concha and the right maxillary sinus. The diagnosis was confirmed by histological studies. Until now no serological or bacteriological cultures have been positive. The patient recovered clinically after surgical debridement and three months of orally administered ciprofloxacin 500 mg twice daily. There remains, however, a sclerotic swelling in the columella and the upper lip. No obvious explanation as to how this patient had caught the disease could be found.

Aged↗
PubMed1996

Effect of colchicine-induced cell loss in the dentate gyrus and Ammon's horn on the olfactory control of feeding in rats.

Normal rats offered a choice between scented and unscented food pellets: (a) avoid food scented with toluene (an aromatic organic solvent) or 2-propylthietane (a component of the anal scent gland secretions of weasels); (b) prefer food scented with cadaverine (a diamine component of the odor of rotting flesh); but (c) neither prefer nor avoid food scented with butyric acid (a component of the odor of rancid butter) or caproic acid (a component of the odor of goats). Lesions of the dentate gyrus and CA1 (induced by local injections of colchicine) and/or the neocortex overlying the hippocampus produce a complex pattern of changes in these normal olfactory reactions, but do not affect the normal reaction to food flavored with sucrose or quinine. Cell loss in the hippocampal formation results in an abnormal aversion to butyric acid, in particular, but neocortical damage also alters the behavioral reaction to scented food. The results are consistent with the view that the hippocampal formation and the neocortex play differing roles in the olfactory control of behavior.

Animals↗
PubMed1996

No sex difference occurs in hippocampus, food-storing, or memory for food caches in black-capped chickadees.

A number of recent studies have described sex differences in the relative size of the hippocampus that are associated with sex differences in the use of space. Voles, kangaroo rats, and cowbirds all exhibit a sex difference in relative size of the hippocampal formation that is correlated with a sex difference in spatial behaviour. We wished to determine whether sex differences in the size of the hippocampus occur in the absence of a difference in the use of space, and whether the previously described correlations could be adventitious. Relative hippocampal size was determined in wild-caught black-capped chickadees (Parus atricapillus) following behavioural observations of food caching and spatial memory for cache sites. There was no indication of a sex difference in either relative size of the hippocampus or in food-caching behaviour and memory for cache sites. These results show that sex differences in relative size of the hippocampus do not occur as a matter of course, and are consistent with the hypothesis that sex differences in spatial behaviour and spatial ability are predictive of sex differences in the relative size of the hippocampus.

Animals↗
PubMed1996

Intracytoplasmic sperm injection does not overcome an oocyte defect in previous fertilization failure with conventional in-vitro fertilization and normal spermatozoa.

A cohort comprising a total of 447 oocyte aspirations due to male factors (n = 258) or to previous fertilization failure by IVF in the presence of normal sperm parameters (n = 189) was studied. We found a significantly reduced implantation and pregnancy rate per transfer in the group with previously failed IVF attempts compared to the male factor group (P < 0.001). No differences were found in age, number of oocytes retrieved, number of embryos transferred or quality of embryos scored at the time of transfer. However, the fertilization and cleavage rates were found to be reduced in the group with previous failed IVF cycles. It is therefore concluded that previous fertilization failure despite normal sperm parameters in an IVF cycle may not be alleviated by the intracytoplasmic sperm injection (ICSI) procedure. These patients might suffer from oocyte defects as well.

Cytoplasm↗
PubMed1996

The utilization rate and pregnancy outcome of multifetal pregnancy reduction in the Nordic countries.

OBJECTIVE: To review the utilization rate and pregnancy outcome of multifetal pregnancy reductions (MFR) in the Nordic countries during the period January 1986-June 1992. STUDY DESIGN: All centers offering assisted conception in Denmark, Finland, Norway and Sweden were retrospectively surveyed by means of a questionnaire with regard to the number and methods used for MFR, pregnancy loss and the outcomes of the pregnancies. The response rate was 100%. RESULTS: During the period studied, 185 births of triplets or higher multiples occurred in Sweden, 120 in Finland and 102 in Denmark. MFR was performed in 42 women (Sweden 26, Finland 10, Denmark 6) but not in Norway at all. This gives an estimated average utilization rate of 1/7 multiple births of three or more in Sweden, 1/17 in Denmark and 1/12 in Finland. The most frequently used method was intracardiac or intrathoracic injection of a potassium chloride solution in gestational weeks 9-12. One pregnancy was reduced from seven to four fetuses, two from five to three, 10 from five to two, one from four to three, 17 from four to two, one from four to one, five from three to two, four from three to one and one from two to one. Nine (21%) pregnancies terminated in a spontaneous abortion within one week (n = 2) to several weeks (n = 7) after the procedure. Of the remaining 33 (79%) pregnancies which continued to delivery, two fetuses died in utero in the second trimester, three infants died perinatally and one child had transverse limb reduction defects. A successful pregnancy defined by the discharge home of at least one infant occurred in 79% of the cases. CONCLUSION: This study gives national estimates on the utilization rate of MFR. Although MFR is performed more frequently in Sweden than in Denmark and Finland, the overall figures remain low in the Nordic countries. The incidence of pregnancy loss in this study is somewhat higher than in several larger reported series, probably reflecting the learning curve of the procedure. It seems reasonable that MFR should be performed in only a few centers in the Nordic countries.

Female↗
PubMed1996

Hyperplasia, hyperproliferation and decreased migration rate of colonic epithelial cells in mice fed a diet deficient in vitamin D.

Low serum levels of vitamin D metabolites have been associated with an increased risk for colon cancer. To investigate the effects of vitamin D deficiency on the colon, 4-week-old mice were fed a diet either containing (100,000 IU/kg diet) or lacking this vitamin for 3 weeks. Food consumption and body weight gain were similar in both groups. Following injection with 3H-thymidine to label dividing cells, cellular proliferation and migration up the colonic crypt were determined autoradiographically. Although overall crypt lengths were similar in both groups, there was hyperplasia and hyperproliferation in crypts of the deficient animals. Also, their epithelial cells migrated up the crypt at a significantly slower rate (maximum 0.78 micron/h) than did those from control mice (1.42 microns/h). There was no difference in cellularity, proliferation or migration in duodenal epithelium. These results indicate that vitamin D deficiency significantly alters colonic but not duodenal epithelial cells.

Animals↗
PubMed1996

Interleukin-1 induced signalling: biphasic activation of mitogen-activated protein kinase kinase and mitogen-activated protein kinases in HeLa cells. Involvement of phosphoprotein phosphatases.

Results of this study document a biphasic activation of protein kinases of the MAP kinase cascade-MEK and MAP kinases-upon interleukin-1 stimulation in human HeLa cells. The specific activities of both MEK and MAP kinases were increased within 1 min, declined rapidly to control levels and increased again after 15 min of interleukin-1 stimulation. Inhibition by okadaic acid of serine/threonine specific phosphatases resulted in a marked increase in interleukin-1 stimulated MEK and MAP kinase activities. Elevation by interleukin-1 of the specific activities of MEK and MAP kinases correlated with suppression of serine/threonine phosphatases in the late phase of stimulation. The data indicate, that enhanced phosphorylation of cellular proteins by enzymes of the MAP kinase cascade might represent a fine balance between activated protein kinases and repressed phosphoprotein phosphatase 2A in interleukin-1 stimulated HeLa cells.

Calcium-Calmodulin-Dependent Protein Kinases↗
PubMed1995

[Fertilization in vitro in the presence of hydrosalpinx and in advanced age].

The purpose of the study was to determine the effect of the presence of a hydrosalpinx and of increasing age on the pregnancy rate after in vitro fertilization (IVF). The presence or absence of a hydrosalpinx was determined by transvaginal ultrasonography before hormonal stimulation of the follicles. The study included 741 women treated in 1090 consecutive cycles in which at least one oocyte was aspirated. The pregnancy rate in 104 cycles in women who had a hydrosalpinx was 6%. In 813 cycles in women with tubal infertility, but without a hydrosalpinx, the rate was 21% (p < 0.0005). A similar pregnancy rate was found in women with unexplained infertility after treatment in 257 cycles. The pregnancy rate in women without a hydrosalpinx decreased from 25% among the women who were 22-29 years old to 11% in the women who were 40-44 years old. In conclusion, the presence of a hydrosalpinx decreases the pregnancy rate after IVF. As tubostomy to improve fertility generally carries a poor prognosis, a salpingectomy prior to IVF may be preferable. Owing to the age-related reduction of the pregnancy rate, IVF should not be put off when indicated for treatment of infertility.

Adult↗
PubMed1995

Experimental allergic encephalomyelitis in non-human primates: MRI and MRS may predict the type of brain damage.

Volume-localized proton spectroscopy and T2-weighted MRI were performed on 23 monkeys with experimental allergic encephalomyelitis (EAE). The purpose of this study was to determine the relationships between temporal changes in lesion activity (measured on T2-weighted MRI), MRS [N-acetyl aspartate (NAA), creatine (CR), choline (CHO)], and the histologic definition of disease determined post-mortem. Animals were scanned in the same areas of the brain once a week before and after sensitization to myelin basic protein (BP). Histologic lesion types were predicted by a combination of preceding MRI and MRS measurements. Acutely fatal EAE lesions were large and monophasic as visualized by MRI, and increased CHO (p < 0.02, n = 16) and CHO/CR ratio (p < 0.001, n = 16) were detected by MRS at disease onset. Chronic EAE lesions were preceded by multiple inflammatory attacks as visualized by MRI and consistently low levels of NAA (p < 0.02, n = 13) and NAA/CR (p < 0.01, n = 13) which occurred after the initial attack. MRI negative brain regions (from animals that were sensitized to BP) were associated with low CHO/CR (p < 0.1, n = 5). The temporal correlation of MRI lesion activity and absolute MRS proton metabolites shows promise for predicting the subsequent duration and histologic type of lesions in EAE in non-human primates.

Animals↗
PubMed1995

Experimental allergic encephalomyelitis in non-human primates: diffusion imaging of acute and chronic brain lesions.

Diffusion imaging and T2-weighted magnetic resonance imaging were performed on 16 monkeys with experimental allergic encephalomyelitis (EAE), a model of the human demyelinating disease MS. The purpose of this study was to determine whether local changes in diffusion image intensity could be correlated with the formation of acute and chronic demyelinating lesions. Diffusion image analysis was restricted to the internal capsule of the brain because of its anatomic orientation of fiber pathways. Acute inflammatory EAE lesions were large and monophasic, as visualized by T2-weighted MRI, and were accompanied by a decrease in the diffusion MR image signal with the diffusion-sensitizing gradient in all three orthogonal directions (n = 27 brain regions, P < 0.005). Chronic demyelinating lesions were preceded by multiple inflammatory attacks, as visualized by MRI, and by a decrease in diffusion MR image signal with the diffusion-sensitizing gradient in the two orthogonal directions perpendicular to the fibers of the internal capsule (n = 18 brain regions, P < 0.005). However, for the chronic group, there was no significant change in the diffusion MR image signal with diffusion-sensitizing gradient parallel to the fibers of the internal capsule at the terminal scan, suggesting little change in the water diffusion within the nerve fibers. These results suggest that diffusion imaging holds promise for measuring subtle changes in water diffusion due to different types of brain damage.

Acute Disease↗
PubMed1995

Perinatal outcome after in vitro fertilisation.

A prospective series of 90 consecutive pregnancies (70 singleton, 16 twin and 4 triplet pregnancies) resulting in births of 114 infants after in vitro fertilisation (IVF) at Rigshospitalet were compared to a control group of pregnancies and deliveries in 70 non-IVF infertility patients with singleton pregnancies and 20 women with normal fertility with twin (n = 16) or triplet (n = 4) pregnancies. No differences in the incidence of third trimester pregnancy complications, abnormal fetal karyotypes or malformations were found. The number of women with spontaneous onset of labor and the gestational age at delivery were similar in the IVF and control groups. In singleton deliveries, the birth weight was lower (p < 0.025) in the IVF group (median 3145 g, range 890-4300 g) than in the control group (3399 g, 2592-4850 g), whereas in multiple gestation similar birth weights were found in the IVF and control groups. We conclude that the birth weight in singleton deliveries after IVF is lower than the birth weight in infertility patients treated differently. The cause of this difference remains obscure.

Adult↗
PubMed1994

[Heterotopic pregnancy after in vitro fertilization].

Until December 1991, 1171 pregnancies had been established in Denmark after in vitro fertilization and embryo transfer (IVF-ET). Thirteen of these pregnancies were heterotopic (1.1%). Three patients were asymptomatic, four patients presented with an acute abdomen, five had abdominal pain and only two patients had vaginal bleeding. In five cases the diagnosis of heterotopic pregnancy was made by ultrasound, while eight cases were diagnosed at the time of surgery. Eleven patients were treated in the first trimester, while two patients were treated at 23 and 38 weeks of gestation, respectively. In nine of the thirteen cases the intrauterine pregnancy resulted in term delivery. Heterotopic pregnancy occurred in 1% of pregnancies following IVF-ET. Abdominal pain was the predominant symptom, while vaginal bleeding was absent in the majority of women. In most cases removal of the ectopic gestation allowed the intrauterine pregnancy to proceed until term.

Adult↗
PubMed1994

Low implantation rate after in-vitro fertilization in patients with hydrosalpinges diagnosed by ultrasonography.

The purpose of this study was to assess whether patients with tubal infertility and a hydrosalpinx have a reduced implantation rate after in-vitro fertilization. The study included 741 patients who had 1190 consecutive oocyte aspirations. The presence or absence of hydrosalpinges was assessed by transvaginal ultrasonography on day 2 of all cycles. In 62 patients treated in 104 cycles a hydrosalpinx was diagnosed, whereas 493 patients treated in 813 cycles had no hydrosalpinx and eight patients treated in 16 cycles had uncertain hydrosalpinx. The results show that the presence of a hydrosalpinx is associated with a reduced pregnancy rate per aspiration (19.2 versus 32.6%; P < 0.01), reduced implantation rate (2.9 versus 10.3%, P < 0.0005), reduced delivery rate per aspiration (5.8 versus 20.9%, P < 0.0005), reduced delivery rate per embryo transfer (6.6 versus 22.8%, P < 0.0005) and increased early pregnancy loss (70 versus 36%, P < 0.005). Among 178 patients with unexplained infertility or other infertility factors treated with 257 aspirations the results were similar to those in patients with tubal infertility without a hydrosalpinx. In conclusion, the presence of a hydrosalpinx does not impair the number of embryos transferred but seems to impair the implantation process. We hypothesize that this may be due to leakage of fluid into the uterine cavity which may disturb the receptivity of the endometrium and/or the developing embryos.

Embryo Implantation↗