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S Petersen

Publications and source records attributed to S Petersen.

At least 109 records · Page 6Linked to original sources
PubMed1997

[Comparative genomic hybridization of bronchial carcinomas and their metastases].

We analysed 150 carcinomas of the respiratory tract and their metastases by Comparative Genomic Hybridization (CGH), a screening method for the detection of chromosomal imbalances in solid tumors. Small cell lung carcinomas (SCLC) and non-small cell lung carcinomas (NSCLC) revealed characteristic patterns of chromosomal alterations with overlapping and specific lesions in both tumor groups. SCLC were defined by a pattern of deletions on chromosomes 3p, 4q, 5q, 10q, 13q and 17p along with overrepresentations of chromosomes 3q and 5p. In contrast, NSCLC carried frequently deletions on chromosomes 1p, 3p, 4q, 5q, 6q, 8p, 9p, 13q, 18q and 21q along with overrepresentations of chromosomes 5p and 11q13. The deletions of the chromosomal band 2q36-q37 together with amplifications of chromosome 3q were statistically significant lesions of squamous cell carcinomas (SCC) whereas adenocarcinomas were characterized in particular by the overrepresentation of chromosome 1q23 and the deletion on chromosome 9q22. The comparison of primary and metastatic tumors revealed that the deletion of chromosome 10q was a statistically significant marker of tumor progression and metastatic phenotype in SCC and SCLC. In conclusion, the data indicate that tumor histotypes and phenotypes are associated with patterns of chromosomal alterations which give important additional information for the classification of human lung carcinomas.

Adenocarcinoma↗
PubMed1996

Infants with gestational age 28 weeks or less.

The objective of the study was to evaluate neonatal survival and subsequent disabilities in infants with extremely low gestational age in relation to perinatal events and neonatal treatment. A retrospective follow-up study was performed based on medical records, questionnaires to parents and recordings of contact with health authorities. All infants with a gestational age 28 completed weeks or less, who were admitted to the Department of Neonatology, Rigshospitalet, within 24 hours of age during the period January 1, 1987 - December 31, 1990 were included. During this period the basic therapeutic approach was a combination of minimal handling and early nasal-continuous positive airway pressure (CPAP) ("minitouch"). Main outcome measures were: mortality, healthy survival and disabled survival. Variables related to outcome were: risk factors present at birth (gestational age, birth weight, gender, place of birth (Rigshospitalet/other hospital), mode of delivery, Apgar score at five minutes; interventions in the neonatal period (intermittent positive pressure ventilation and treatment of hypotension); complications in the neonatal period (intracranial haemorrhage grade II-IV, periventricular leucomalacia, pneumothorax, seizures and septicaemia). One hundred and ninety-seven infants without major malformations were included. The mortality rate was 29%. Among infants with gestational age 24-25 weeks 49% died versus 24% of infants born after 26-28 weeks (p = 0.004). Mean gestational age was 26.7 weeks (range 24-28) and mean birth weight 994 g (range 525-1630). Fifty-five infants (28%) were small-for-gestational age. One hundred and fifty-five infants (79%) were born in our hospital and 115 (58%) were delivered by caesarean section. A total of 140 infants (71%) survived until discharge and none died between discharge and follow-up. At follow-up at a mean uncorrected age of 48 months information was obtained about all infants, except two (1%) who had emigrated; 75 (54%) had no impairments, 31 (22%) had minor impairments, 17 (12%) were moderately disabled, and 15 (11%) were severely disabled. Of the 197 infants 121 (61%) were treated with intermittent positive pressure ventilation, 83 (42%) with dopamine for hypotension, and 92 (47%) received parenteral nutrition. In 64 infants (33%) the course was complicated with intracranial haemorrhage (ICH) grade II-IV, in 17 (9%) with seizures, in 23 (12%) with pneumothorax, in 21 (11%) with septicaemia, and in 10 (5%) with necrotizing enterocolitis. Sixty infants (31%) needed medical or surgical closure of a persistent ductus arteriosus. In 11 infants (6%) cystic periventricular leucomalacia occurred, 10 infants (5%) developed retinopathy of prematurity stage 3-4, and 35 infants (24%) received supplementary oxygen at 28 days of age. Risk factors present at birth for adverse outcome were: Apgar score <7 at five minutes, birth weight <1000 g, male sex and birth in another hospital than Rigshospitalet, For adverse outcome in surviving infants only, ICH grade II-IV was the only significant risk factor.

Female↗
PubMed1995

Insulin-dependent regulation of Glut4 gene expression in ventricular cardiomyocytes: evidence for a direct effect on Glut4 transcription.

The present study examined the effect of insulin on Glut4 transcription in isolated ventricular cardiomyocytes. Upon exposure to the hormone (2 x 10(-7) M) the cellular Glut4 mRNA content increased to 224 +/- 46% of control within 3.5 hours. Nuclear run-on analysis indicated a parallel increase of transcription of the Glut4 gene to 208 +/- 49% of control. Direct incubation of cardiac nuclei with insulin resulted in a comparably significant increase of Glut4 transcription. Cross-linkage experiments with 125I-labelled insulin demonstrated the absence of soluble nuclear insulin receptors, which were readily detected in plasma and microsomal membranes. These findings suggest that expression of the cardiac Glut4 gene is subject to regulation by insulin at the transcriptional level, a process possibly involving nuclear association of the hormone.

Animals↗
PubMed1995

[Neonatal hypoglycemia--new limits for treatment?].

Neonatal hypoglycaemia is the commonest clinical manifestation af disordered energy metabolism and is important because sustained hypoglycaemia may cause neuronal damage. Infants at high risk of developing low brain energy levels are those who have increased metabolic demands, low glycogen reserves, insufficient counter-regulatory responses or hyperinsuliaemia, and there is accumulating evidence that blood glucose should be maintained above 2.5 mM in this group. If possible, early and regular feeding at a volume of 120 ml/kg/dag should be established, but supplementation with intravenous glucose may be necessary.

Age Factors↗
PubMed1995

Prediction of birth weight by ultrasound-estimated fetal weight: a comparison between single and repeated estimates.

OBJECTIVES: Ultrasound estimation of fetal weight is used for diagnosing intrauterine growth retardation. The aim of the present study was to assess the accuracy of birth weight prediction by use of a single or repeated estimations of fetal weight in the third trimester. STUDY DESIGN: 1000 pregnant women considered at risk were scheduled to ultrasound estimation of fetal weight, using Warsof's formula, at 28, 31, 34 and 37 weeks of gestation. The 421 pregnancies with term delivery and complete set of ultrasound examinations and 57 pregnancies with preterm delivery with ultrasound examination at 16 and 28 weeks and once more before delivery were included in the present analysis. RESULTS: The accuracy of birth weight prediction improved significantly for every three weeks from 28 to 37 weeks of gestation in the term infants. Prediction based on the average of repeated weight estimates or linear extrapolation from two estimates or extrapolation by a second order polynomium fitted to four estimates did not improve accuracy compared to prediction based on the last estimate before delivery. CONCLUSION: When more than one ultrasound estimation of fetal weight are available, prediction of birth weight in relation to gestational age should be based on the last ultrasound examination only.

Birth Weight↗
PubMed1995

Spin-lattice relaxation time of inorganic phosphate in human tumor xenografts measured in vivo by 31P-magnetic resonance spectroscopy. Influence of oxygen tension.

Previous 31P-magnetic resonance spectroscopy (31P-MRS) studies have suggested that the spin-lattice relaxation time (T1) of the inorganic phosphate (Pi) resonance is shorter in well-oxygenated than in poorly oxygenated tumors. Amelanotic human melanoma xenografts were therefore subjected to 31P-MRS to investigate whether the T1 of the Pi resonance might be a useful parameter for assessment of tumor oxygenation status. It was searched for possible correlations between the T1 of the Pi resonance and oxygen tension or parameters closely related to oxygen tension, including 31P-MRS tumor energy status and blood supply per viable tumor cell. Oxygen tension, tumor energy status, and blood supply per viable tumor cell decreased with increasing tumor volume. In contrast to previous suggestions, the T1 of the Pi resonance decreased with increasing tumor volume and decreasing oxygen tension, tumor energy status, and blood supply per viable tumor cell, possibly because the tumors developed necrotic regions concomitantly with the decrease in oxygenation status, resulting in increased concentrations of freely dissolved para-magnetic ions in the tissue. Consequently, the T1 of the Pi resonance can probably not be utilized to estimate the oxygenation status of tumors, at least not in tumors with necrotic regions.

Animals↗
PubMed1994

G protein expression and adenylate cyclase regulation in ventricular cardiomyocytes from STZ-diabetic rats.

Isolated adult ventricular cardiomyocytes have been used to study the effects of insulin-deficient diabetes on the expression of cardiac G protein alpha-subunits. Immunoblot analysis of plasma membranes revealed the presence of three different Gs proteins with molecular masses of 45, 47, and 52 kDa. Furthermore, cardiomyocytes were found to contain Gi-2 (41 kDa) and G(o) (39 kDa). Heart cells from streptozotocin-diabetic rats exhibited an unaltered expression of the Gs proteins, whereas Gi-2 and G(o) were reduced by 58 +/- 2 and 27 +/- 11%, respectively. In cells from diabetic rats, adenosine 3',5'-cyclic monophosphate (cAMP) accumulation in response to isoproterenol decreased by approximately 30% at agonist concentrations of 10(-7) to 10(-5) M, with an unaltered maximum stimulation by forskolin. Treatment of cardiomyocytes with pertussis toxin resulted in an incremental increase of isoproterenol-stimulated cAMP formation, which was significantly lower in cardiac myocytes from streptozotocin-diabetic animals (19.2 +/- 1.7 vs. 11.5 +/- 2.4 pmol cAMP.5 x 10(4) cells-1 times 10 min-1). The inhibition of the isoproterenol-induced cAMP accumulation by carbachol in the intact cell was not altered in streptozotocin-diabetes. In conclusion, our data show that insulin-deficient diabetes is associated with a reduced expression and concomitant functional loss of Gi in ventricular cardiomyocytes. Receptor-mediated inhibition of adenylate cyclase remains unaffected by this process, whereas the beta-adrenergic stimulatory pathway involves an additional defect upstream of the adenylate cyclase/G protein system.

Adenylyl Cyclases↗
PubMed1994

Weight, length, head circumference, and growth velocity in a longitudinal study of Danish infants.

Two longitudinal studies of infant growth, performed from 1985 to 1988 in the Copenhagen area, have been combined to develop an up-to-date growth reference. Percentile curves were constructed and median growth velocities were calculated for monthly intervals, based on individually estimated growth curves. Compared with references based on data from periods when the prevalence of breast-feeding was low, these data support previous suggestions of a new growth pattern, with higher velocities during the first months and slower velocities during the remaining infancy. The growth of breast-fed infants differs from that of infants not being breast-fed, and special growth references for breast-fed infants have been suggested. We therefore examined growth patterns in the present study according to duration of breast-feeding. At 12 months, infants breast-fed > or = 9 months weighed less (400 g (95% CI: 70 g, 740 g) and were 1.0 cm shorter (0.3 cm, 1.8 cm) than infants breast-fed < 9 months. Part of this difference was already present at six months. Despite this we recommend a single growth reference for Danish infants regardless of mode of feeding. The slower growth in infants breast-fed > or = 9 months, which could be due to differences in composition of weaning foods, should be investigated further.

Body Height↗
PubMed1993

[Transportation of sick newborn infants].

In a six month period, 96 newborn infants were transferred from local hospitals to the Department of Neonatology, State University Hospital (Rigshospitalet), Copenhagen. Complications related to transport and potential risk factors were registered prospectively. Considering the condition of the infants, 31% of the transports were not carried out under optimal conditions. Serious complications occurred in 13% of the transports of infants at risk for cardio-pulmonary insufficiency. In 25% of the intubated infants, complications related to displacement of the tracheal tube were observed on arrival, but in only one of these cases the complication was recognized and treated during transport. Hypothermia occurred frequently in low birth weight infants. Failing monitoring equipment and difficulties with stethoscopy and other observations during transport may have contributed to the fatal outcome in one case. Careful planning of neonatal transports according to listed recommendations and considering the specific problems in each case may prevent complications.

Cecal Diseases↗
PubMed1993

"Minitouch" treatment of very low-birth-weight infants.

In a cohort study with historical controls of non-asphyxiated very low-birth-weight infants (birth weight < or = 1500 g and gestational age < 33 completed weeks), we evaluated the use of a "minitouch" regime for stabilization after birth and treatment of respiratory distress. This combination of early (prophylactic) treatment with nasal continuous positive airway pressure and minimal handling was introduced as a routine in our Department in 1986. We compared infants born in 1987 and in 1985, when ventilator treatment was used initially in all infants with progressing respiratory distress. The frequency of mechanical ventilation was reduced significantly from 76% in 1985 to 35% in 1987 (p = 0.00001). This reduction reflected the smaller number of infants who received ventilator treatment for less than one week, whereas the frequency of long-term ventilator treatment remained unchanged. Intracranial haemorrhage grade II-IV was reduced from 49% in 1985 to 25% in 1987 (p = 0.01). Mortality rate, average duration of hospitalization, number of infants with pneumothorax, patent ductus arteriosus, need for oxygen at 28 days and number of surviving infants with handicap did not differ significantly between the two study periods. Septicaemia was diagnosed in 16% of the infants in 1987 versus 7% in 1985 (p = 0.045). This difference coincided with an increased use of total parenteral nutrition (18% in 1987 versus 3% in 1985, p = 0.007). We conclude that the minitouch regime prevents progression of respiratory distress, reduces the need for ventilator treatment and is a safe and convenient alternative to mechanical ventilation in preterm infants with mild respiratory problems.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral Hemorrhage↗
PubMed1992

Judging fetal growth from body proportions at birth.

Fetal growth velocity from 27 weeks until birth was calculated in 378 infants born after high risk pregnancies from at least three ultrasound measurements of estimated fetal weight and the weight at birth. Anthropometric measurements at birth (weight, head circumference, length, ponderal index and skinfolds), after correction for differences in gestational age, were significantly related to fetal growth velocity. The relation between fetal growth velocity and ponderal index was significant (correlation coefficient = 0.34, P < 0.001). However, the correlations between fetal growth velocity and each of the anthropometric measures disappeared when birth weight relative to gestational age was accounted for. This means that given the birth weight and the gestational age of a newborn infant, body proportions, e.g. ponderal index or skinfold thickness, do not contribute further to the judgment about fetal growth rate.

Anthropometry↗
PubMed1992

An unusual genomic position effect on Drosophila white gene expression: pairing dependence, interactions with zeste, and molecular analysis of revertants.

The white gene in the AR4-24 P[white,rosy] insertion on chromosome 2 has a novel expression pattern, in which it is repressed in the dorsal half of the eye. X-ray mutagenesis led to the isolation of six revertants mapping to chromosome 2, which are wild type in a zeste+ background, and three extreme derivatives, in which white gene expression is repressed in ventral regions of the eye as well. By Southern blot analyses the breakpoints of five of the revertants and one of the extreme derivatives were mapped in the flanking DNA bordering each side of the AR4-24 insertion. The revertants show some dorsal repression of white in the presence of z1, and by this criterion each is only a partial revertant. The extreme derivatives act not only in cis, but also in trans to repress expression of AR4-24 and its various derivatives. We provide evidence that these trans effects are proximity-dependent effects, possibly mediated by pairing of gene copies, as they do not extend to copies of the white gene located elsewhere in the genome. We show that one extreme derivative, E1, is a small deletion spanning the insertion site at the 5' end of the white gene, and propose that the distance between a negative regulatory element in the 5' flanking DNA and the white promoter influences the degree of the repression.

Animals↗
PubMed1992

Detection of small-for-gestational-age fetuses by ultrasound screening in a high risk population: a randomized controlled study.

OBJECTIVE: To assess the value of fetal weight estimation during routine third trimester ultrasound examinations for the identification of small-for-gestational-age (SGA) fetuses, to promote active pregnancy management and so reduce perinatal morbidity. DESIGN: A prospective controlled randomized study. SETTING: Outpatient clinic at the Department of Obstetrics, Herlev University Hospital, Denmark. SUBJECTS: One thousand pregnant women considered at risk were selected consecutively from April 1985 to September 1987 and randomized to either a revealed-results group or a withheld-results group. INTERVENTION: All the women had an early ultrasound examination for estimation of gestational age. Both groups had routine ultrasound estimates of fetal weight after 28 weeks and then every third week until delivery. The results were available for clinical use only in the revealed group. MAIN OUTCOME MEASURES: Number of interventions during pregnancy (admission to hospital, elective delivery), emergency intervention during labour, and fetal outcome. RESULTS: Revealing the results of ultrasound estimates of fetal weight for gestational age during the third trimester resulted in statistically significantly increased diagnosis of SGA fetuses, of elective deliveries based on this diagnosis, and of healthy preterm babies admitted to the neonatal care unit, but no detectable overall improvement in weight for gestational age at birth, or in neonatal morbidity or mortality. CONCLUSION: This method of screening improved the diagnosis of SGA fetuses, but this was not followed by improved fetal outcome.

Birth Weight↗
PubMed1991

Inverse regulation of glucose transporter Glut4 and G-protein Gs mRNA expression in cardiac myocytes from insulin resistant rats.

The present study examined the mRNA levels of glucose transporter Glut4 and G-protein Gs alpha-subunit in isolated ventricular myocytes from lean and genetically obese (fa/fa) Zucker rats and streptozotocin-diabetic rats. In obese animals the amount of transcripts coding for Glut4 increased to 122 +/- 6% of lean controls, whereas the mRNA coding for Gs alpha-subunit decreased by 42 +/- 12%. An unaltered level of Gs mRNA was observed in insulin deficient rats. When cardiomyocytes from normal rats were treated with insulin, the Glut4 transcript level increased by 48 +/- 5%, whereas the Gs mRNA level decreased by 55 +/- 8%. The findings suggest that insulin may act as a potential regulator of Glut4 and Gs mRNA expression in the cardiac cell.

Animals↗
PubMed1991

Nonradioactive, sequence-specific detection of RNA in situ by primed in situ labeling (PRINS).

A new method for the detection of RNA in situ is presented. It is based on sequence-dependent annealing of unlabeled specific oligonucleotide primers to intracellular RNA and subsequent chain elongation catalyzed by reverse transcriptase. Under the conditions described, biotin-labeled nucleotides can be incorporated and the cDNA synthesized in situ can thus be detected using fluorescein-conjugated avidin. Compared to traditional in situ hybridization the use of short oligonucleotide primers has the potential advantage of being better to discriminate between closely related RNA transcripts. Compared to in situ transcription with radioactive precursors we find it more attractive to use fluorescein-conjugated avidin as detection system because it allows a more detailed study of cell and signal simultaneously.

Animals↗
PubMed1991

Immunoglobulin and complement studies in children with Schönlein-Henoch Syndrome and other vasculitic diseases.

In 35 children with Schönlein-Henoch Syndrome (SHS) serum IgG, IgM, and IgA concentrations were increased in 15%, 21%, and 44% of cases, respectively. Seven children with other vasculitic syndromes (VS) had normal serum Ig concentrations. Serum concentration of IgG subclass IgG1 was increased in 72% of children with SHS and 57% with VS. In SHS this was related to the presence of arthritis, but inversely related to nephritic symptoms. Only a few children had IgG subclasses IgG2, IgG3, or IgG4 concentrations outside the normal ranges. Platelet associated Ig (PAIg) was found in 75% of children with SHS or VS. In SHS the identification of increased amounts of PAIgG was related to the presence of nephritis. The serum concentration of properdin, a component of the alternative complement system, was reduced in 21% of children with SHS. This was related to the presence of abdominal symptoms or nephritis. No cases of retinal vasculitis was observed, but 4 of 22 children with SHS had punctuate retinal haemorrhages. SHS and VS may be clinical variations of the same syndrome. The immunological aspects indicate a close relationship with autoimmune diseases.

Adolescent↗
PubMed1991

[The occurrence of Campylobacter spp. and Salmonella spp. in gulls in northern Germany].

Out of a total of 207 gulls--20 Black headed gulls, 185 Herring gulls and 2 Common gulls--128 (62%) and 23 (11%) birds, respectively, were infected with Campylobacter spp. (C.) and Salmonella spp. C. jejuni was predominant in gulls less than two years old (89%) and C. coli in older birds (75%). Furthermore, the infection rate with Campylobacters was depending on the habitats of the birds. The rate for C. jejuni and C. coli, respectively, was in gulls from regional garbage dumps 78% and 4%, from the coast 58% and 21%, and from islands 47% and 47% of the isolations in the corresponding area. Salmonellae were mainly isolated in the period from September to February from gulls less than one year old and from birds from the coast.

Animals↗