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Biomedical subjects

J M Maltau

Publications and source records attributed to J M Maltau.

At least 37 records · Page 2Linked to original sources

Effect of probenecid, verapamil and progesterone on the concentration-dependent and temperature-sensitive human erythrocyte uptake and export of guanosine 3',5' cyclic monophosphate (cGMP).

Elevated extracellular cGMP levels have been observed in various clinical conditions, and the analyte has been proposed as a diagnostic marker of cardiovascular as well as malignant diseases. However, the use of extracellular cGMP as a pathophysiological marker requires detailed knowledge about the cellular biokinetics of cGMP (synthesis, metabolic conversion and export). In the present study the transport of cGMP in human erythrocytes has been further characterized. The uptake of cGMP was dependent on a concentration gradient and was temperature-sensitive, compatible with passive diffusion. The cGMP export was temperature-sensitive, saturable (Km = 3.4 +/- 1.0 mu mol l-1), inhibited by probenecid and verapamil and stimulated by progesterone. The results show that human erythrocytes possess a cGMP transport system similar to that found in other cells and that extracellular levels of cGMP are dependent on intracellular levels, membrane transport and influenced by physiological factors and pharmacological agents.

Biological Transport↗

[Transcervical resection of the endometrium. An alternative to hysterectomy in dysfunctional uterine hemorrhage].

Transcervical electroresection of the endometrium was performed in 104 patients with dysfunctional uterine bleeding which did not respond to conservative treatment. Transcervical resection was offered as an alternative to abdominal hysterectomy. Re-resection was performed in 17 women (16%) because the initial section did not have the desired effect. Altogether 122 resections were performed. 79% of the women were satisfied after the initial resection and 93% when the procedure was repeated. During a follow-up period of six to 28 months after treatment, a hysterectomy was performed in 18 (17%) patients, but unacceptable uterine bleeding was the indication in only five of these cases. One major complication occurred, a small bowel perforation which required intestinal resection. Three uterine perforations occurred without any damage to neighbouring organs. Except for transient headache in a few patients, no clinical symptoms of glycine toxicity were seen. It is concluded that transcervical endometrial resection seems to represent an additional option for surgical treatment of dysfunctional uterine bleeding, but the procedure is not without risk. The long-term results of this procedure must be compared with those achieved by traditional abdominal hysterectomy.

Adult↗

Progesterone reduces sympathetic tone without changing blood pressure or fluid balance in men.

There is scant information on the effects of progesterone on circulation. Changes in catecholamine levels, blood pressure and transcapillary fluid balance were measured in 12 men before and during administration of natural progesterone (Utrogestan). Before administration, systolic blood pressure was significantly correlated with venous adrenaline (r = 0.67, p = 0.01). There was a significant decrease (p = 0.004) in venous noradrenaline during progesterone administration, and systolic blood pressure was significantly correlated with the arteriovenous difference for noradrenaline (r = 0.66, p = 0.02). Serum progesterone, which attained levels similar to those found in women during the luteal phase, did not significantly alter blood pressure, body weight or intra- to extravascular fluid shift. It is concluded that progesterone may have a direct action by increasing the uptake of noradrenaline from the synaptic cleft or by decreasing the nerve firing rate. Interestingly, the pretreatment finding of a significant correlation between blood pressure and adrenaline was less evident during progesterone administration.

Adult↗

Evidence for altered transcapillary fluid balance in women with the premenstrual syndrome.

Redistribution of body fluids has been suggested as a possible pathophysiological mechanism for the premenstrual syndrome (PMS). To elucidate this hypothesis, transcapillary fluid balance was studied in ten women with well defined PMS. Wick-methods were used for measuring colloid osmotic and hydrostatic interstitial pressures on the thorax and on the leg. The capillary filtration coefficient was measured by strain gauge plethysmography. From the follicular to the luteal phase the interstitial colloid osmotic pressure on the leg was significantly reduced (mean 3.6 mm Hg, p = 0.005), whereas the interstitial colloid osmotic pressure on the thorax remained constant. The capillary filtration coefficient increased 30% (mean 5.3 x 10(-4) ml/min/100 gm/mm Hg, p = 0.04) from the follicular to the luteal phase. No change was observed in body weight. These findings indicate an instability of vascular regulation in women with premenstrual syndrome, and lend support to the hypothesis that redistribution of fluid, rather than water retention, is responsible for the subjective symptoms such as bloatedness, in the premenstrual syndrome.

Adult↗

[Streptococci group B and pregnancy. Need for routine check-ups?].

Group B streptococci are a major cause of perinatal infections and affect 1-5 infants out of every 1,000 live births. Maternal vaginal colonization with these bacteria is common (5-25%), and has been associated with late abortions, foetal growth retardation, early rupture of membranes and premature delivery. Colonization with group B streptococci may be observed in more than 70% of neonates born to mothers with the bacteria in their vaginal tracts at delivery. A high number of bacteria in the maternal urogenital tract during pregnancy may predispose to early-onset disease in neonates. The estimated attack rate in colonized neonates is 1-2%. A high specific IgG antibody concentration in the mother may protect the infant, but probably not before 32 weeks of gestation. Colonized women who are unable to produce such antibodies risk having affected offspring. Neonatal infection with group B streptococci frequently results in death or permanent neurologic morbidity; especially from the early-onset type (case-fatality more than 50%) which is most often vertical transmitted. Four cases with early-onset disease illustrate the severity of perinatal group B streptococcal infections. The severity and outcome of the disease may be moderated by screening for group B streptococci during late pregnancy. This screening must be combined with special attention to irregularities in pregnancy or perinatal complications.

Adult↗

Increased capillary permeability for plasma proteins in oral contraceptive users.

The transcapillary fluid balance was examined in eleven women before administration of a monophasic oral contraceptive (desogestrel 0.15 mg, ethinylestradiol 0.03 mg), and after three and six months of use. The interstitial colloid osmotic pressure was measured by the "wick" method, and the interstitial hydrostatic pressure by the "wick-in-needle" method in subcutaneous tissue on thorax and leg. During the six-month observation period, the following changes were observed: Plasma colloid osmotic pressure decreased (mean 1.8 mmHg, p = 0.047), as well as serum albumin (mean 5.1 g/l, p = 0.0006), total protein concentration (mean 2.8 g/l, p = 0.0006), hemoglobin (mean 0.5 g/dl, p = 0.014) and hematocrit (mean 1.8%, p = 0.047). Blood pressure and body weight remained unchanged, but foot volume showed a significant increase. The colloid osmotic pressure gradient (plasma-interstitium) was significantly reduced. The results indicate an increase in plasma volume in addition to an increased capillary permeability to plasma proteins during oral contraceptive use. We suggest that the observed changes in transcapillary fluid balance is caused by the estrogen component of the oral contraceptive pill.

Adolescent↗

[Conservative treatment of ectopic pregnancy].

During the last decades the incidence of ectopic pregnancy has been steadily rising. The chosen therapy has usually been unilateral salpingectomy. Recently, different conservative (tube-preserving) treatment-modalities have been introduced in clinical practice. We have tried conservative treatment by local injection of prostaglandin F2a (total dose 2-4 mg) directly into the tubal pregnancy and, if feasible, also into the corpus luteum graviditate. The treatment was successful in 13 out of 16 patients. In one patient laparotomia was performed because of pain, and revealed a haematoma in fossa Douglasi. Reinjection of prostaglandin was necessary in one patient because of rising HCG titres. One patient was hospitalized for four days because of nausea and pain. The treatment was otherwise successful. The method may be useful as a non-surgical alternative in haemodynamically stable patients without tubal rupture. Further studies are needed to evaluate the outcome in terms of future fertility.

Chorionic Gonadotropin↗

Handling of tubal infertility after introduction of in vitro fertilization: changes and consequences.

This study aimed at quantifying some important social and economic consequences of the altered handling of tubal infertility after the establishment of IVF treatment. The number of tubal operations was reduced by 50%. This had most important and positive implications on the availability of the operating theater for other elective operations, on the availability of hospital beds for other patient groups, and on the total duration of the certificate of illness. The calculated costs per live birth were $17,000 after tubal surgery, compared with $12,000 after IVF treatment. Life table analyses demonstrated a highly significant increased rate of deliveries after a complete IVF treatment (72.3% per patient) compared with tubal surgery (23.7%, P less than 0.001).

Adult↗

[Complications following cesarean section].

During a seven-years period, 898 women (9.9% of all deliveries) had a cesarean section at the Department of Obstetrics and Gynecology, University Hospital of Tromsø. 29.3% of the women suffered one or more complications (8.5% intraoperative, 23.1% postoperative). The most common complication was infection (22.3%). The following factors were associated with the occurrence of complications: emergency operation, obesity, labor prior to surgery, increased duration of labor or rupture of fetal membranes prior to operation, low gestational age, and station of the presenting part of the fetus below the ischial spinal plane. The same tendency was found for intra- and postoperative complications. Hb levels less than 12.0 g/100 ml increased the risk of infection. We suggest ways of reducing both the number of cesarean sections and the number of complications.

Cesarean Section↗

Transcapillary fluid dynamics during ovarian stimulation for in vitro fertilization.

Transcapillary fluid dynamics were studied in 10 women during ovarian stimulation for in vitro fertilization. The examinations were done on the first day of stimulation (day 3 of the menstrual cycle, mean serum estradiol concentration 0.2 nmol/L), and the day before oocyte aspiration (day 10 to 12, mean serum estradiol concentration 6.8 nmol/L). Interstitial colloid osmotic pressure was measured on the thorax at heart level by the "wick" method, and interstitial hydrostatic pressure by the "wick-in-needle" method. Plasma colloid osmotic pressure decreased (mean, 2.0 mm Hg; p less than 0.002) and interstitial colloid osmotic pressure increased (mean, 1.0 mm Hg; p less than 0.02) during hormonal stimulation. This implies a reduced transcapillary colloid osmotic gradient (plasma colloid osmotic pressure--interstitial colloid osmotic pressure), probably because of increased capillary permeability to plasma proteins. Hemoglobin and hematocrit were significantly reduced, and body weight and foot volume significantly increased. These results demonstrate that during ovarian stimulation there are both water retention and augmented filtration of fluid from the vascular to the interstitial compartment. This may be of significance for the pathophysiologic condition in the ovarian hyperstimulation syndrome.

Adult↗

Plasma secretin concentrations during normal human pregnancy, delivery, and postpartum.

Plasma concentrations of secretin were measured at 4-week intervals throughout eight normal pregnancies and again twice postpartum, and in another six women during parturition and the early postpartum period. Comparisons were made with levels in 16 normal non-pregnant women. Plasma secretin concentrations increased during pregnancy with maximum levels at 36 weeks. The increase was statistically significant from week 28 to 36, compared with non-pregnant levels. By 5 days after delivery plasma secretin levels were similar to the non-pregnant levels. No significant changes in plasma secretin were observed during delivery and early postpartum. The altered secretin levels may be of importance for heartburn in pregnancy, calcium metabolism, and the changes in renal haemodynamics.

Adult↗