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S Gudmundsson

Publications and source records attributed to S Gudmundsson.

At least 19 recordsLinked to original sources
PubMed2002

Increased expression of interleukin-13 but not interleukin-4 in CD4+ cells from patients with the hyper-IgE syndrome.

Hyper IgE syndrome (HIES) is a rare immunodeficiency disorder characterized mainly by high levels of polyclonal IgE in serum and recurrent staphylococcal abscesses of the skin and lungs. The raised IgE levels have led researchers to study the synthesis of cytokines that regulate switching of immunoglobulin production towards IgE such as interleukin-4 (IL-4), IL-12 and interferon-gamma (IFN)-gamma. However, the role of IL-13 in the disease pathogenesis has not been investigated extensively. In this study, we investigated intracellular expression of IL-4 and IL-13 in mononuclear cells and CD4+ cells isolated from patients with HIES and healthy controls. Cells were stained intracellularly with antibodies directed against IL-4 and IL-13 and analysed by flow cytometry before and after activation with PMA and calcium ionophore. The mean proportion of resting or activated IL-4 and IL-13 expressing mononuclear cells were comparable in the two groups as well as the proportion of IL-4 expressing CD4+ cells. In contrast, the mean proportion of IL-13 expressing CD4+ cells was increased significantly in patients with HIES in both the resting and the activated state compared to healthy controls. We conclude that increased expression of IL-13 in CD4+ cells from patients with HIES could account, at least partly, for raised IgE levels in those individuals.

CD4-Positive T-Lymphocytes↗
PubMed2002

Can the degree of retrograde diastolic flow in abnormal umbilical artery flow velocity waveforms predict pregnancy outcome?

OBJECTIVE: Reverse end-diastolic flow is the most pathological type of the umbilical artery flow velocity waveform. We aimed to investigate whether additional prognostic information can be obtained from umbilical artery waveforms in cases with reverse end-diastolic flow. SUBJECTS AND METHODS: Umbilical artery Doppler velocity waveforms from 44 fetuses with reverse end-diastolic flow were analyzed and the following parameters measured: the highest amplitude and the area below the maximum velocity curve of forward and reverse flow (A, B and C, D, respectively) and the duration of forward and reverse flow (Tc and Td, respectively). Ratios A/B, C/D and Tc/Td were calculated. The cut-off values for A/B, C/D and Tc/Td with the best predictive values for perinatal death were established with the help of receiver operating characteristics curves. The three curves were compared with each other. RESULTS: Of the three ratios, A/B and C/D had the best capacity to predict perinatal death. Both ratios had acceptable sensitivities, specificities and positive predictive values. In this regard, A/B and C/D were comparable. The cut-off values for A/B and C/D were 4.3 and 4.52, respectively. Survivors had I significantly higher A/B and C/D ratios than non-survivors (P = 0.0001 and 0.0003, respectively). Significantly more fetuses with A/B or C/D below the established cut-off values had pulsations in the venous system (P < 0.05). In fetuses with a gestational age < =210 gestational days the survival rate was significantly higher in those with A/B or C/D above the cut-off values (P = 0.03 and 0.003, respectively). CONCLUSIONS: The A/B or C/D ratio can be used for quantification of the reverse end-diastolic flow waveforms in the umbilical artery and may offer additional information to the evaluation of fetal condition.

Blood Flow Velocity↗
PubMed2002

Uterine artery score and perinatal outcome.

OBJECTIVE: To evaluate a modified uterine artery score based on the pulsatility index and presence or absence of notching in the Doppler velocity waveform recorded from both uterine arteries in relation to the perinatal outcome. METHODS: A retrospective analysis was performed in 741 third-trimester high-risk pregnancies. The uterine artery score was constructed assigning one point to each abnormal parameter-high pulsatility index and presence of notch-thus ranging from 0 (normal findings in both uterine arteries) to 4 (notch and high pulsatility index in both uterine arteries). In a subgroup with lateral placenta (n = 359), two definitions of abnormal pulsatility index were compared. In the uniform uterine artery score, a pulsatility index > 1.20 in both uterine arteries was considered abnormal, disregarding the placental location; in the subgroup with lateral placenta, the high pulsatility index was defined as > 1.00 on the placental side and > 1.40 on the non-placental side. RESULTS: Receiver-operating characteristic curves did not reveal any difference in the diagnostic capacity between the group with a uniform uterine artery score and the subgroup with lateral placenta (P = 0.54). In the total material, the odds ratios and linear regression analysis showed an increased risk for an adverse perinatal outcome with increasing uterine artery score (P < 0.01). At a uterine artery score > 2, there was a significantly increased risk for operative delivery for fetal distress, neonatal intensive care unit admission, 5-min Apgar score < 7, preterm delivery and delivery of a small-for-gestational age fetus. CONCLUSION: In high-risk third-trimester pregnancies, Doppler velocity waveforms of the uterine arteries can be evaluated using the uterine artery score disregarding the placental location. The uterine artery score possesses a high predictive value regarding adverse perinatal outcome.

Adult↗
PubMed2002

Blood redistribution in the fetal brain during chronic hypoxia.

BACKGROUND: Studies on blood flow velocity in the fetal middle cerebral artery have revealed signs of brain sparing in chronic hypoxia. These signs of brain sparing can disappear in the terminal case, but whether this applies to the whole brain or only parts of it is unknown. METHODS: Velocity waveforms of the middle cerebral, anterior cerebral and posterior cerebral arteries were recorded in 221 pregnancies complicated by pregnancy-induced hypertension. The presence of brain sparing (pulsatility index < 2 standard deviations) was noted and correlated to outcome of pregnancy, including emergency operative intervention and/or neonatal distress. RESULTS: Signs of brain sparing in the anterior cerebral artery were found in 90 fetuses, and in the middle cerebral and posterior cerebral arteries in 52 and 65, respectively. Signs of brain sparing in the anterior cerebral artery showed the strongest relationship to adverse perinatal outcome. The anterior cerebral artery was the only vessel in which signs of brain sparing were predictive of perinatal mortality. CONCLUSIONS: Velocimetry of the anterior cerebral artery appears to be superior to that of the middle cerebral and posterior cerebral arteries as a means to predict adverse perinatal outcome. Anterior cerebral artery brain sparing may therefore be less transitory than sparing in the middle cerebral and posterior cerebral arteries, possibly suggesting that the frontal lobes are spared longer than the lateral and occipital regions of the fetal brain.

Adult↗
PubMed2002

Venous Doppler velocimetry in the surveillance of severely compromised fetuses.

OBJECTIVE: To investigate whether venous Doppler velocimetric signs of cardiac decompensation might predict fetal demise in severely compromised fetuses. MATERIAL AND METHODS: This was a prospective study involving 154 growth-restricted fetuses, 37 of which were found to have reversed flow in the umbilical artery (BFC III). Doppler velocimetry of the right hepatic vein and ductus venosus were investigated serially and the presence of umbilical venous pulsations also registered. Only the final examination prior to birth or fetal demise was accepted for analysis and related to obstetric outcome defined as gestational age at birth, birth weight and perinatal mortality. In cases of BFC III the venous velocimetry of 15 nonsurviving fetuses was compared to that of the 22 survivors. RESULTS: There was a significant correlation between venous blood velocity and placental vascular resistance. In the right hepatic vein there was a significant decrease in peak systolic and end-systolic velocities and an increase of maximum velocity during atrial contraction and pulsatility (P < 0.05). A decrease of all velocities and increase of pulsatility were noted in the ductus venosus (P < 0.05). A reversed flow in the ductus venosus was found in 9/37 fetuses and double umbilical venous pulsations in 16/37 fetuses. However, the hepatic vein seemed to be a better predictor of impending mortality than the ductus venosus. Changes in diastolic venous blood velocity and a double pulsation in the umbilical vein were closely related to perinatal mortality, although these parameters did not provide a useful threshold to optimize the timing of delivery. CONCLUSION: Diastolic venous velocimetry changes significantly in severely compromised fetuses. These changes might be of great clinical value in deciding on the timing of delivery to minimize damage to the fetus and newborn.

Blood Flow Velocity↗
PubMed2002

An algorithm including results of gray-scale and power Doppler ultrasound examination to predict endometrial malignancy in women with postmenopausal bleeding.

OBJECTIVE: To determine if power Doppler ultrasound examination of the endometrium can contribute to a correct diagnosis of endometrial malignancy in women with postmenopausal bleeding and endometrium > or = 5 mm. METHODS: Eighty-three women with postmenopausal bleeding and endometrium > or = 5 mm underwent gray-scale and power Doppler ultrasound examination using predetermined, standardized settings. Suspicion of endometrial malignancy at gray-scale ultrasound examination (endometrial morphology) was noted, and the color content of the endometrium at power Doppler examination was estimated subjectively (endometrial color score). Computer analysis of the most vascularized area of the endometrium was done off-line in a standardized manner. Stepwise multivariate logistic regression analysis was carried out to determine which subjective and objective ultrasound and power Doppler variables satisfied the criteria to be included in a model to calculate the probability of endometrial malignancy. RESULTS: Endometrial thickness, vascularity index (vascularized area/endometrial area), and use of hormone replacement therapy (HRT) satisfied the criteria to be included in the model used to calculate the 'objective probability of endometrial malignancy'. Endometrial morphology, endometrial color score and HRT use satisfied the criteria to be included in the model to calculate the 'subjective probability of malignancy'. Endometrial thickness > or = 10.5 mm had a sensitivity with regard to endometrial cancer of 0.88 and a specificity of 0.61. At a fixed sensitivity of 0.88, the specificity of the 'objective probability of malignancy' (0.81) was superior to all other ultrasound and power Doppler variables (P = 0.001-0.02). The 'objective probability of malignancy' detected more malignancies at endometrium 5-15 mm than endometrial morphology (5/7 vs. 1/7, i.e. 0.71 vs. 0.14; P = 0.125) with a similar specificity (49/57 vs. 51/57, i.e. 0.86 vs. 0.89). CONCLUSION: Power Doppler ultrasound can contribute to a correct diagnosis of endometrial malignancy, especially if the endometrium measures 5-15 mm. The use of regression models including power Doppler results to estimate the risk of endometrial cancer deserves further development.

Aged↗
PubMed2001

Blood velocity in the fetal vein of Galen and the outcome of high-risk pregnancy.

BACKGROUND: Pulsation in the flow velocity waveform in the umbilical vein is related to perinatal mortality but the flow velocity waveform in the fetal vein of Galen is normally even and without fluctuation. OBJECTIVES: To establish whether blood flow velocity pulsations in the vein of Galen in high-risk pregnancies are related to outcome. STUDY DESIGN: The vein of Galen was located by colour Doppler ultrasound in 102 pregnancies complicated by severe pregnancy-induced hypertension. The blood velocity waveform was recorded by pulsed Doppler within 2 days of delivery and the presence pulsations related to pregnancy outcome, including emergency operative intervention and neonatal distress. Umbilical artery and vein and uterine artery blood flow velocity waveform were also recorded at the same time. The clinicians managing the women were unaware of the venous flow results. RESULTS: Pulsation were present in the vein of Galen in 68 cases and in the umbilical vein in 21. Both were significantly related to adverse outcome. Pulsations in the vein of Galen were seen in all seven perinatal deaths. CONCLUSIONS: Since umbilical venous pulsation are a late sign of fetal compromise, and pulsations in the vein of Galen seem to appear earlier, thus being an intermediate sign of fetal compromise that might be of great value for fetal surveillance.

Asphyxia↗
PubMed2001

Two types of umbilical venous pulsations and outcome of high-risk pregnancy.

Normally, blood flows evenly in the umbilical vein, without fluctuation. A pulsating pattern has been reported during fetal heart failure and asphyxia. Recently we have noticed two types of pulsating pattern; its relationship to adverse outcome is unclear. In a prospective multicenter study, recording of umbilical cord venous blood flow was conducted in high-risk pregnancies admitted for routine artery Doppler. In cases of pulsating flow or signs of vascular resistance in the umbilical artery, the examination was extended to the intra-abdominal part of the umbilical vein. Venous pulsation, single or double, were noted and correlated to perinatal outcome. Venous flow pulsatility was noted in 83 fetuses during 2 years, 26 had a double pulsating pattern, which was closely related to increased vascular resistance in the umbilical artery and perinatal mortality. A single pulsating venous pattern in one location had a good prognosis. In conclusion a double pulsating venous pattern, especially if extending to the cord, is an ominous finding in high-risk pregnancy associated with poor perinatal outcome. A single pulsating pattern predicted a much better outcome and might be an indication for delivery in the high-risk case.

Female↗
PubMed2001

Comparison of power Doppler and velocimetry in predicting outcome of high-risk pregnancy.

OBJECTIVE: Prospectively evaluate semi-quantitative computer analysis of power Doppler (PD) signals in the placenta, tetal brain, lung, liver, kidney and spleen in high-risk pregnancies in relationship to perinatal outcome and also to compare tissue blood flow in the fetal brain and placenta with Doppler velocimetry. METHODS: PD signals were recorded in 180 high-risk pregnancies between 27 and 41 weeks of gestation. Images from PD angiographic scans were transmitted for computer analysis of pixel intensity. Mean flow signal intensity was recorded for each organ. The PD brain/lung ratio was calculated. The PD results were plotted on reference values and related to perinatal outcome. Middle cerebral (MCA), umbilical (UA) and uterine artery (Ut. A) velocimetry was also performed. RESULTS: High-risk pregnancies displayed lower PD signal intensity from the placenta, fetal lung, liver and kidney as compared to normals. However, the brain and spleen signals showed higher intensities suggesting increased tissue perfusion. PD signals from the fetal brain, lung, placenta and PD brain/lung ratio were correlated with perinatal outcome. The PD signal intensity from the fetal liver, kidney and spleen showed poor correlation with perinatal outcome. Fetal brain tissue blood flow showed better correlation with the outcome than MCA velocimetry. Placental tissue blood flow results were similar in predicting outcome to those obtained by means of UA and Ut. A velocimetry. CONCLUSION: In comparison with conventional Doppler velocimetry, computer analysis of PD signals, give similar results in the prediction of adverse perinatal outcome.

Blood Flow Velocity↗
PubMed2001

Maternal carriership of factor V Leiden associated with pathological uterine artery doppler measurements during pregnancy.

To determine whether increased vascular resistance in the uterine artery is associated with carriership of factor V Leiden, a retrospective study was undertaken of 231 pregnant women who were monitored with Doppler velocimetry of the uterine arteries. These women had been part of a prospective study of 2,480 pregnant women in whom factor V Leiden had been analysed. When compared with non-carriers of factor V Leiden, carriers had a tendency towards an increased proportion of pathological Doppler measurements, including a significant increase in bilateral uterine artery notches (7/33 vs 16/198, relative risk 3.1; 95% CI 1.2-8.1). This suggests an increased vascular resistance in the uteroplacental circulation among carriers of factor V Leiden.

Arteries↗
PubMed2001

Penicillin pharmacodynamics in four experimental pneumococcal infection models.

Clinical and animal studies indicate that with optimal dosing, penicillin may still be effective against penicillin-nonsusceptible pneumococci (PNSP). The present study examined whether the same strains of penicillin-susceptible pneumococci (PSP) and PNSP differed in their pharmacodynamic responses to penicillin by using comparable penicillin dosing regimens in four animal models: peritonitis, pneumonia, and thigh infection in mice and tissue cage infection in rabbits. Two multidrug-resistant isolates of Streptococcus pneumoniae type 6B were used, one for which the penicillin MIC was 0.016 microg/ml and the other for which the penicillin MIC was 1.0 microg/ml. Two additional strains of PNSP were studied in the rabbit. The animals were treated with five different penicillin regimens resulting in different maximum concentrations of drugs in serum (C(max)s) and times that the concentrations were greater than the MIC (T(>MIC)s). The endpoints were bacterial viability counts after 6 h of treatment in the mice and 24 h of treatment in the rabbits. Similar pharmacodynamic effects were observed in all models. In the mouse models bactericidal activity depended on the T(>MIC) and to a lesser extent on the Cmax/MIC and the generation time but not on the area under the concentration-time curve (AUC)/MIC. Maximal bactericidal activities were similar for both PSP and PNSP, being the highest in the peritoneum and blood (approximately 6 log10 CFU/ml), followed by the thigh (approximately 3 log10 CFU/thigh), and being the lowest in the lung (approximately 1 log10 CFU/lung). In the rabbit model the maximal effect was approximately 6 log10 CFU/ml after 24 h. In the mouse models bactericidal activity became marked when T(>MIC) was > or =65% of the experimental time and C(max) was > or =15 times the MIC, and in the rabbit model bactericidal activity became marked when T(>MIC) was > or =35%, Cmax was > or =5 times the MIC, and the AUC at 24 h/MIC exceeded 25. By optimization of the Cmax/MIC ratio and T(>MIC), the MIC of penicillin for pneumococci can be used to guide therapy and maximize therapeutic efficacy in nonmeningeal infections caused by PNSP.

Animals↗
PubMed2001

Doppler velocimetry in the evaluation of fetal hypoxia.

Knowledge of fetal hemodynamic physiology has developed enormously during the last two decades due to Doppler ultrasound. Some of this knowledge has been utilized for routine surveillance of high-risk pregnancies. The prediction of fetal hypoxia before the development of life lasting sequel is of major importance, especially in the very premature case with absent end-diastolic blood flow in the umbilical artery before lung maturity. This review gives an overview of the present knowledge in this field.

Adrenal Glands↗
PubMed2001

Primary Sjögren's syndrome--treatment of fetal incomplete atrioventricular block with dexamethasone.

Pregnancies in women with autoantibodies against Ro/SSA and/or La/SSB may be associated with permanent and treatment resistant fetal atrioventricular (AV) block. We describe a patient with primary S ogren's syndrome and anti-Ro (60 kDa and 52 kDa) and anti-La autoantibodies, in whom fetal bradycardia with second-degree AV block was detected at 19 + 0 weeks of gestation. Maternal treatment with dexamethasone (4 mg/day po) was started 2 days later. The baby's heart rate improved gradually, returning to normal after about 6 weeks of treatment. Our case illustrates the importance of close monitoring of the fetal heart rate in risk-pregnancies from about week 16 of gestation and initiation of dexamethasone treatment without delay when a block is detected.

Adult↗
PubMed2000

Prevalence of postherpetic neuralgia after a first episode of herpes zoster: prospective study with long term follow up.

OBJECTIVE: To estimate the frequency, duration, and clinical importance of postherpetic neuralgia after a single episode of herpes zoster. DESIGN: Prospective cohort study with long term follow up. SETTING: Primary health care in Iceland. PARTICIPANTS: 421 patients with a single episode of herpes zoster. MAIN OUTCOME MEASURES: Age and sex distribution of patients with herpes zoster, point prevalence of postherpetic neuralgia, and severity of pain at 1, 3, 6, and 12 months and up to 7.6 years after the outbreak of zoster. RESULTS: Among patients younger than 60 years, the risk of postherpetic neuralgia three months after the start of the zoster rash was 1.8% (95% confidence interval 0.59% to 4.18%) and pain was mild in all cases. In patients 60 years and older, the risk of postherpetic neuralgia increased but the pain was usually mild or moderate. After three months severe pain was recorded in two patients older than 60 years (1.7%, 2.14% to 6.15%). After 12 months no patient reported severe pain and 14 patients (3.3%) had mild or moderate pain. Seven of these became pain free within two to seven years, and five reported mild pain and one moderate pain after 7.6 years of follow up. Sex was not a predictor of postherpetic neuralgia. Possible immunomodulating comorbidity (such as malignancy, systemic steroid use, diabetes) was present in 17 patients. CONCLUSIONS: The probability of longstanding pain of clinical importance after herpes zoster is low in an unselected population of primary care patients essentially untreated with antiviral drugs.

Adolescent↗
PubMed2000

Fetal adrenal and middle cerebral artery Doppler velocimetry in high-risk pregnancy.

OBJECTIVES: Animal studies have shown that hypoxic fetuses redistribute their blood flow, giving preferential supply to the brain, heart and adrenal glands. The aim of this study was to establish whether blood velocity waveforms in the human fetal adrenal artery and middle cerebral artery showed signs of redistribution of fetal circulation in high-risk pregnancy, and to analyze the relationship between signs of such redistribution and the outcome of pregnancy. METHODS: Fetal middle adrenal artery and middle cerebral artery waveforms were recorded between 27 and 41 weeks of gestation in 102 pregnancies complicated by pregnancy-induced hypertension. Signs of fetal adrenal-sparing were deemed present when the pulsatility index (PI) fell below the fifth percentile of the normal range. Signs of fetal brain-sparing were deemed present when the cerebral artery PI was below the mean -2 SD of the normal range and the cerebroplacental PI ratio was < 1.08. RESULTS: Signs of adrenal sparing were found in 64 cases and brain sparing in 32 cases. Fetal adrenal sparing was strongly associated with adverse perinatal outcome; all perinatal mortality cases showed signs of adrenal sparing. There was a significant positive correlation between the fetal adrenal artery PI and umbilical arterial and venous pH. CONCLUSIONS: Signs of adrenal sparing are frequent in high-risk pregnancies. Adrenal artery velocimetry may be a useful procedure for fetuses at risk for hypoxemia.

Adrenal Glands↗
PubMed2000

TT virus infections among blood donors in Iceland: prevalence, genotypes, and lack of relationship to serum ALT levels.

BACKGROUND: The TT virus (TTV) is a newly identified blood-borne virus. Its association with disease is still unknown, and screening of blood donors has not been implemented. Several genotypes of the TTV have been identified. STUDY DESIGN AND METHODS: Three hundred seventy healthy blood donors were randomly selected and tested for TTV by the PCR method. Sequencing of a part of the genome was performed to identify various genotypes of the virus. ALT levels were determined in both infected and uninfected individuals. RESULTS: The TT virus (TTV), was detected in the sera of 23 (6.2%) of 370 healthy Icelandic blood donors; this prevalence is lower than that reported in Japan but higher than that in Scotland. The virus was found in all groups over the age of 19. Sequencing and phylogenetic analysis of 202 bp from open reading frame 1 demonstrated genotypes 1b and 2b 2c and genotype 4 isolates, with the latter bearing 89-percent nucleotide homology with other genotype 4 sequences deposited at GenBank. One sample showed a mixed genotype 1b/2c infection. Serum ALT levels were within normal limits in all infected individuals. CONCLUSION: The TTV carrier state does not cause significant liver injury.

Adolescent↗
PubMed2000

Qualitative study of pregnancy and childbirth experiences in Somalian women resident in Sweden.

OBJECTIVE: To explore the attitudes, strategies and habits of Somalian immigrant women related to pregnancy and childbirth, in order to gain an understanding as to how cultural factors might affect perinatal outcome. METHODS: Interpreter assisted qualitative in depth interviews around topics such as attitudes and strategies regarding childbirth. PARTICIPANTS: Fifteen women from the Somalian community in a city in Sweden, between the ages of 20 and 55 years with delivery experience in Somalia and Sweden. RESULTS: The interviews describe how the women themselves perceived their experiences of childbirth in the migrant situation. Many voluntarily decreased food intake in order to have a smaller fetus, an easier delivery and to avoid caesarean section. The participants considered a safe delivery to be the same as a normal vaginal delivery They reduced food intake in order to diminish the growth of the fetus, thereby avoiding caesarean section and mortality. The practice of food intake reduction, while rational for the participants when in Somalia, was found less rational in Sweden and may lead to suboptimal obstetric surveillance. CONCLUSIONS: Somalian women have childbirth strategies that differ from those of Swedish women. These strategies should be seen as 'survival behaviours' related to their background in an environment with high maternal mortality. The hypothesis generated is that there is a relationship between the strategies during pregnancy and adverse perinatal outcome among Somalian immigrants. Considering the strong association of the habits to safe birth, it seems doubtful whether the women will change their habits as long as health care providers are unaware of their motives. We suggest a more culturally sensitive perinatal surveillance.

Adult↗