PubMed Health⌕ Search

Biomedical subjects

K Kristoffersen

Publications and source records attributed to K Kristoffersen.

At least 37 records · Page 2Linked to original sources
PubMed1989

Cross sectional early mitral flow velocity profiles from colour Doppler.

Instantaneous cross sectional flow velocity profiles from early mitral flow in 10 healthy men were constructed by time interpolation of the velocity data from each point in sequentially delayed two dimensional digital Doppler ultrasound maps. This interpolation allows correction of the artificially produced skewness of velocities across the flow sector caused by the time taken to scan the flow sector for velocity recording of pulsatile blood flow. These results suggested that early mitral flow studied in an apical four chamber view is variably skewed both at the leaflet tips and at the annulus. The maximum flow velocity overestimated the cross sectional mean velocity at the same time by a factor of 1.2-2.2. Also the maximum time velocity integral overestimated the cross sectional mean time velocity integral to the same extent. This cross sectional skew must be taken into account when calculation of blood flow is based on recordings with pulsed wave Doppler ultrasound from a single sample volume.

Adolescent↗
PubMed1986

Pregnancy following kidney transplantation.

Following kidney transplantation, 20 women gave birth to 24 infants after the 28th gestational week. All babies were singletons, alive, and free from malformations. The mean weight was 2,595 g (range 1,420-3,200 g) and the mean gestational age was 37.8 weeks (range 32-40 weeks). The cesarean section rate was 75%. On dividing the patients into low- and high-risk groups, the rate of pre-eclampsia, prematurity, and intra-uterine growth retardation was 2-3 times as high in the high-risk as in the low-risk group. No patients experienced graft rejection during the pregnancy but, within 3 months after delivery, two rejection episodes occurred. Later, a further 5 patients experienced graft rejection. All infants developed normally. We conclude that pregnancy following renal transplantation generally has a normal outcome and that the function of the transplanted kidney is unaffected by the pregnancy.

Adult↗
PubMed1984

Immune monitoring of pregnancy in renal transplanted patients.

Immune studies were performed in eight pregnancies occurring after renal transplantation (tx). In three cases a regular, long-term immune monitoring before, during, and after the pregnancy was possible. The results showed 1) no changes concerning OKT 3, 4, 8, and SMIg-defined T- and B-lymphocyte subsets in the mothers: 2) a higher level of spontaneous E- and normal E-rosette-defined T-subsets in the mothers rejecting their allografts; 3) a stronger response to mitogen and antigen stimulation and a stronger mixed lymphocyte culture (MLC) response towards the infants also in those rejecting their grafts; 4) the offspring of the transplanted mothers showed a weaker immune responder state compared with the offspring of six age-matched normal mothers.

Antibodies, Monoclonal↗
PubMed1980

The fetus as an allograft: a longitudinal study of normal human pregnancies studied with mixed lymphocyte cultures between mother-father and mother-child.

A longitudinal investigation of the mixed lymphocyte culture (MLC) response during pregnancy between mother and father, between mother and child, and between the mother and an indifferent lymphocyte pool has been carried out, using starting values before pregnancy and a cryobiological freezing system that allows in vitro playback of the immunological course of pregnancy. Lymphocyte and serum samples from twenty-two pregnant women taken before and during pregnancy, at delivery, and after delivery were used. The study shows that the mother reacts during the course of pregnancy with an increasing MLC response to the father, which is replaced at delivery by a decrease in response and a subsequent increase after delivery. It is also shown that the mother reacts to the child in a similar manner at about half the level of reaction to the father. The mother also reacts similarly to a pool of indifferent lymphocytes. The MLC reactions mentioned are affected by both non-pregnant and pregnant serum, leading to a moderation of the MLC reaction in relation to that carried out in neutral AB serum. In addition, there seems to be cooperation between cellular and humoral factors, since the MLC reaction to the child carried out in relevant autologous serum seems to show a decreasing response during the course of pregnancy, in accordance with increasing tolerance of the fetal allograft.

Female↗
PubMed1980

Lymphocyte transformation with mitogens and antigens during normal human pregnancy: a longitudinal study.

In a longitudinal analysis of immunological changes in normal human pregnancy, twenty-two pregnant women were studied, with blood samples taken before pregnancy, during its course, at delivery, and 3-5 months after delivery. The blood samples were frozen successively, using a cryobiological freezing system, and were stored until the whole longitudinal series was obtained. The collected material for a longitudinal series was then thawed and tested in one seance. Lymphocyte transformation tests were performed with stimulation with the mitogens phytohaemagglutinin (PHA), pokeweed mitogen (PWM), concanavalin A (Con A) and the specific antigens tuberculin purified protein derivative (PPD), Candida albicans (CA), Staphylococcus aureus (SA) and streptokinase/streptodornase (SK/SD). No changes were found in PHA or in PWM responses, whereas there were significant changes in the Con A response, with lowest values in the middle of pregnancy. PPD, CA, SA and SK/SD responses all reached lowest values towards the end of pregnancy, with increases subsequently, after delivery. These findings seem to show that T suppressor function is increased and B-lymphocyte function decreases during the course of pregnancy.

Candida albicans↗
PubMed1980

Ritodrine in the treatment of preterm labour. A clinical trial to compare a standard treatment with three regimens involving the use of ritodrine.

In a randomized trial, three alternative schemes of treatment of preterm labour with ritodrine (long infusion, short infusion, and intramuscular injection) were compared with standard treatment by bed rest and sedatives. None of the ritodrine treatments were found to be better in postponing delivery than the standard treatment. However, the Bishop scores of the patients in the standard treatment group tended to be lower than of the patients treated with ritodrine. Moreover, all cases of congenital malformation and polyhydramnios occurred in the patients treated with ritodrine. The incidence of respiratory insufficiency was significantly higher in infants of mothers treated with ritodrine. The mean birth weight was highest in the standard treatment group.

Adult↗
PubMed1980

Pulsed Doppler ultrasound for measuring blood flow velocity in the human ophthalmic circulation.

This study was performed in order to develop a method for studying blood flow in the ophthalmic circulation. Using a pulsed doppler system utilizing an ultrasonic frequency of 10 MHz, blood flow velocities have been measured in the ophthalmic artery and in the arteries behind the eyeball (lateral posterior ciliary arteries) in 40 normal subjects. The mean of the peak systolic velocities were 34 +/- 6 cm/s in the ophthalmic artery, and 14 +/- 3 cm/s in the lateral posterior ciliary arteries. We conclude that blood flow velocities can be measured in defined vessel areas in the orbit.

Adolescent↗