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Biomedical subjects

L Hamberger

Publications and source records attributed to L Hamberger.

At least 109 records · Page 6Linked to original sources
PubMed1987

Role of ultrasound in infertility.

The use of ultrasound technology and its further prospects in an infertility clinic are described. First, the ultrasonic ovarian scanning during the follicular phase of stimulated cycles is discussed. With this technique the number and size of the follicles, and the thickness of the endometrium can be estimated. Second, three different routes for ultrasound guided follicle puncture are described, namely the transvesical, the transvaginal and the perurethral puncture. Finally, the ultrasound guided embryo transfer procedure is explained.

Embryo Transfer↗
PubMed1986

Oxygen consumption by human oocytes and blastocysts grown in vitro.

Oxygen consumption by human oocytes and blastocysts was analysed using a sensitive micro-spectrophotometric technique. Oocytes were obtained from women undergoing laparotomy for sterilization or hysterectomy, and blastocysts were obtained as spare embryos from the local in-vitro fertilization programme. There was no significant difference between oocyte oxygen consumption on the day of isolation and after 1 day of culture, 0.53 +/- 0.08 (n = 9) and 0.35 +/- 0.06 (n = 5) nl/h oocyte, respectively. Blastocyst oxygen consumption was measured after a culture period of 5-8 days after in-vitro fertilization. Mean oxygen consumption by healthy looking blastocysts was 0.34 +/- 0.03 (n = 15) nl/h blastocyst, and there was no change in oxygen consumption with culture time. This level of respiration was lower than expected, both when compared with the oocytes and when compared with levels reported for blastocysts of other species.

Blastocyst↗
PubMed1986

Neuropeptide Y and noradrenaline in human uterus and myometrium during normal and pre-eclamptic pregnancy.

The myometrial levels of noradrenaline (NA) and neuropeptide Y (NPY), a recently discovered neuropeptide that coexists with NA in many sympathetic nerves, have been measured by immunohistochemistry and biochemistry in normal and pre-eclamptic pregnancy and compared with non-pregnant controls. In the non-pregnant uterus there were high levels of NA and NPY and a rich presence of NA/NPY nerves in the myometrium and around blood vessels. In pregnancy both substances were significantly lower as compared with non-pregnant women. Five patients with pre-eclampsia had levels of NA/NPY that were less markedly reduced than in normal pregnant women. The results show that NA and NPY coexist also in human uterine nerves, and that both decrease significantly during pregnancy. Since both substances are vasoactive, the observed reduction might be of physiological importance for normal pregnancy.

Female↗
PubMed1986

Interaction between prostaglandin E2 and noradrenalin on collagen synthesis in human cervical tissue during pregnancy.

The effects of prostaglandin E2 (PGE2) and noradrenalin (NA) on the incorporation of [3H]proline in cervical tissue of pregnant women were investigated. NA inhibited the incorporation in early as well as in term pregnancy. PGE2 counteracted the NA-effect in the former group of patients but did not affect the influence of NA at term. The results demonstrate an interaction between PGE2 and NA and point to a hitherto unknown effect of NA in the regulation of cervical connective tissue metabolism.

Cervix Uteri↗
PubMed1985

[Hereditary salt sensitivity as a cause of essential hypertension: studies of membrane transport and intracellular electrolytes].

Based on oscillatory long-term blood pressure recordings and on biochemical findings in 62 normotensive and 54 untreated hypertensive subjects, who were investigated during their usual high sodium diet and after moderate salt restriction, we have developed a concept for the pathogenesis of essential hypertension, which differs from current concept proposed by others: We demonstrated that normotensive subjects with a positive family history of hypertension respond to sodium restriction from 200 to 50 mmol/day over 2 weeks with a minute fall of mean blood pressure of 2.9 +/- 0.7 mmHg (+/- SEM), whereas in subjects with a negative family history of hypertension blood pressure remained unchanged (-0.93 +/- 0.67 mmHg). This difference was only revealed by computing the "basal blood pressure average" from 240 heart beats, but not by conventional sphygmomanometric blood pressure measurements. Normotensives with heredity of hypertension or "salt sensitive" normotensive subjects were not different from subjects with a negative family history in the sodium pump, Na-K-cotransport or intracellular sodium and potassium of erythrocytes. In contrast, the former group had an increased sensitivity to infused noradrenaline, which might be responsible for enhanced tubular sodium reabsorption in subjects with a positive family history of hypertension (or "salt sensitive" subjects). We only found an increased K-permeability of red cells in established hypertension, which was compensated for by a an increased activity of the sodium pump. These cell membrane defects were more pronounced in more severe hypertension. In the course of essential hypertension a cell membrane defect may develop as a consequence rather than a cause of the disease.

Adult↗
PubMed1985

Simplification of the method of in vitro fertilization: sonographic measurements of follicular diameter as the sole index of follicular maturity.

As a simplification of the in vitro fertilization (IVF) procedure, repeated sonographic scanning of follicular diameters in stimulated cycles was performed, until the largest visible follicle reached a mean diameter of at least 20 mm, at which time human chorionic gonadotropin (hCG) was administered. Follicle puncture was performed either guided by sonography or by laparoscopy 34-36 hr after the hCG injection, and following insemination oocytes were cultured for 48-60 hr before embryo transfer (ET). Serum levels of luteinizing hormone (LH), prolactin (PRL), and estradiol-17 beta (E2) at the time of hCG injection as well as follicular fluid levels of follicle stimulating hormone (FSH), LH, and PRL as well as progesterone (P), testosterone (T), and E2 at the time of puncture were determined in retrospect using specific radioimmunoassay (RIA). It was found that the knowledge of a single value of LH or E2 in serum should have been of little additional value for the decision to give hCG in all stimulation models used: clomiphene + hCG, human menopausal gonadotropin (hMG) + hCG, and clomiphene + hMG + hCG. The concentrations of the three steroids measured in follicular fluid were, in a high proportion of the follicles, within a normal range in all stimulation models. The group receiving clomiphene + hMG + hCG appeared promising through its higher proportion of estrogenic follicles. It is concluded that sonographic measurement of follicular diameters may be used as the sole index of follicular maturity in an IVF program.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Effect of gonadotrophins on progesterone secretion by cultured granulosa cells obtained from human preovulatory follicles.

Granulosa cells were obtained from human preovulatory follicles in 31 women undergoing in vitro fertilization and embryo transfer due to tubal infertility. Follicular maturation was stimulated and synchronized by treatment with Clomiphene or human menopausal gonadotrophin (hMG), or both, plus human chorionic gonadotrophin (hCG). Follicles were aspirated by ultrasound guided puncture approximately 34-36 h after the hCG injection. The granulosa cells were washed and suspended in modified medium 199 containing 10% foetal bovine serum and cultured as monolayers for 6-8 days in the absence and presence of hormones and reactants. Progesterone formation was analyzed by RIA. In general, the cells underwent morphological luteinization and secreted high amount of progesterone. Under basal conditions the secretion of progesterone was highest during the first 2 days in culture and then gradually declined. Progesterone secretion was stimulated by human LH, hCG and the adenylate cyclase stimulator forskolin, with a maximal effect between days 2-6. The beta-adrenergic agonist isoproterenol in preliminary experiments potentiated the stimulatory effect of hCG but had no own stimulatory effect. No clear differences in progesterone secretion or responsiveness to in vitro stimulation relating to the various in vivo stimulation protocols were found.

Cell Count↗
PubMed1985

Effects of a low-dose desogestrel-ethinylestradiol combination on hirsutism, androgens and sex hormone binding globulin in women with a polycystic ovary syndrome.

Twenty women suffering from a polycystic ovary syndrome (PCO) accompanied by hirsutism were given a low-dose oral contraceptive combination containing 0.150 mg desogestrel plus 0.030 mg ethinylestradiol for 8 months. The pretreatment situation regarding hair and hormone profiles in the PCO group was compared with that in 22 regularly menstruating women. Serum levels of free and total testosterone and androstenedione were significantly elevated in PCO women, as were body weight, blood pressure, hair diameter and depilation frequency. Sex hormone binding globulin (SHBG) binding capacity was lower. Following treatment of the PCO group for 8 months, total and free testosterone levels were depressed, but androstenedione had not changed significantly. SHBG binding capacity was increased five-fold. Body weight decreased in the obese women. Hair growth was significantly suppressed and the hair itself was less coarse. Depilation intervals were longer. Acne, present before the treatment had now disappeared. Blood pressure did not change. Few and mild side effects were recorded. After treatment, 3 women succeeded in becoming pregnant and in 8 others spontaneous menstruations had recurred.

Adult↗
PubMed1985

Lipid metabolic studies in women with a polycystic ovary syndrome during treatment with a low-dose desogestrel-ethinylestradiol combination.

Twenty women with the polycystic ovary syndrome (PCO) were treated with a combination of desogestrel and ethinylestradiol (EE) and the effects on lipids and lipoproteins were compared with those induced in a group of 13 regularly menstruating, healthy women. All women were examined before and after 3 months of treatment. Compared with the regularly menstruating women, the PCO women had significantly higher body weights and blood pressure as well as elevated levels of triglycerides in serum and VLDL. During treatment, 14 out of 20 women affected by PCO lost weight. No significant change in blood pressure was observed. In the PCO group, moderate increments were encountered in serum cholesterol, phospholipids and triglycerides. No significant changes were seen in LDL-cholesterol or HDL-cholesterol. The ratio LDL-cholesterol/HDL-cholesterol did not alter. The level of total cholesterol in VLDL rose during treatment. These changes in serum and lipoprotein lipids in PCO patients were of the same type and magnitude as those found in the control group, apart from an increase in HDL-cholesterol in the latter. The only remaining difference after treatment was a slightly higher level of VLDL triglycerides in the PCO women. Thus only moderate changes were induced in lipid and lipoprotein patterns by the combination of desogestrel and EE. A "positive" influence on lipids and lipoproteins cannot be considered as a further advantage, added to the list of indications when hormonal treatment is used in PCO-affected women. The clinical implications of elevated triglycerides remain to be clarified.

Adult↗
PubMed1985

Ovarian steroid production in a woman with polycystic ovary syndrome associated with endometrial cancer.

A young woman with typical polycystic ovary syndrome (PCO) underwent laparotomy for moderately differentiated endometrial cancer. Specimens from the hyperplastic thecal and stromal tissue of the ovaries were incubated for 2 hours in the presence or absence of hCG, 100 IU/ml. Following incubation the tissue content of cyclic AMP and the amounts of progesterone (P), androstenedione (A), testosterone (T) and estradiol-17 beta (E2) in the incubation medium were analysed. For comparison, thecal cells from normal ovaries of regularly menstruating women were incubated under identical conditions. In vivo, the PCO ovaries secreted several-fold greater amounts of T than normal ovaries. In vitro, the thecal cells were much more active, steroidogenically, than the stromal cells of the PCO ovary. Furthermore, the hyperplastic thecal cells of the PCO ovary produced several-fold greater amounts of androgens, and appeared more sensitive to stimulation with hCG, as compared with thecal cells from normal ovaries. The results indicate that in women with PCO associated with endometrial cancer the hyperplastic thecal cells are a significant site of abnormal androgen production and abnormal sensitivity to gonadotropin.

Adenocarcinoma↗
PubMed1985

Raised sodium pump activity and a circulating sodium transport inhibitor demonstrated on red blood cells of patients with untreated essential hypertension: correlation of pump activity with potassium permeability.

We have studied sodium potassium ATPase activity, the effect of endogenous plasma on sodium pump activity, potassium permeability and intracellular sodium and potassium concentrations in normotensive subjects without (n = 36) and with (n = 33) a positive family history of hypertension, and in patients with untreated essential hypertension (n = 52). Sodium pump activity was studied as ouabain sensitive uptake of rubidium 86 in washed red blood cells, incubated in an artificial medium closely resembling the anorganic constituents of plasma. Any influence of endogenous plasma on sodium pump activity was investigated by re-incubating the washed red blood cells in their own plasma and comparing ouabain sensitive rubidium uptake in the two media. To correct for any possible differences in external potassium concentration, a function for the relation between extracellular potassium concentration and absolute transport rates was derived experimentally. From this, actual transport rates in plasma were corrected by computer to an extracellular potassium concentration of 4.0 mmol/l. Sodium pump activity, concentration of circulating sodium transport inhibitor, potassium permeability and intracellular electrolytes were not statistically different in subjects with and without a positive family history of hypertension. Hypertensives had significantly raised sodium pump activity in artificial medium, but not when red cells were re-incubated in their own plasma. Thus, endogenous plasma inhibited the sodium pump by between 12% and 15%. Hypertensives also had a significantly raised potassium permeability. Potassium permeability and sodium pump activity were correlated significantly. Intracellular sodium concentrations were similar in normotensives and hypertensives, but the later showed a significantly lower intracellular potassium concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Salt sensitivity in normotensives with and salt resistance in normotensives without heredity of hypertension.

We have studied blood pressure responses to moderate sodium restriction from 200 to 50 mmol/day over 2 weeks in 62 normotensive subjects with and without a family history of hypertension by continuous automatic blood pressure recording. Based on the average of the blood pressure of 1 hour continuous monitoring under basal conditions, we have been able to demonstrate a significant fall of blood pressure in 28 young subjects with a heredity of hypertension after moderate sodium restriction from 200 to 50 mmol over 2 weeks (fall in systolic blood pressure 5.4 +/- 1.1, diastolic 2.5 +/- 0.8, mean blood pressure 2.9 +/- 0.7 mmHg, mean +/- SEM), whereas blood pressure remained unchanged in a group of 34 subjects without heredity of hypertension after moderate sodium restriction (change in systolic blood pressure -1.0 +/- 0.6, diastolic blood pressure -0.6 +/- 0.7 and mean blood pressure -0.93 +/- 0.67 mmHg). 29 of the subjects were studied a third time 2 weeks after having returned to their usual high sodium diet and in those in whom a blood pressure fall was observed during sodium restriction it returned to pre-intervention values. This demonstrates that normotensives with a heredity of hypertension are salt sensitive and adds further evidence that a high sodium intake may be of critical importance for the initiation of essential hypertension.

Adult↗
PubMed1984

Ultrasound as a diagnostic and operative tool for in vitro fertilization and embryo replacement (IVF/ER) programs.

Diagnostic ultrasound offers unique possibilities to study ovarian morphology, especially follicular growth and development. This makes the technique an important tool for the management of ovulation induction in an in vitro fertilization and embryo replacement (IVF/ER) program. Different general aspects of the use of ultrasound in IVF/ER are discussed in this communication.

Adult↗
PubMed1984

Granulosa and thecal cells from human ovarian follicles under growth: steroid formation in vitro and responsiveness to human chorionic gonadotropin.

In order to characterize the patterns of steroid production and gonadotropin responsiveness in growing human follicles, follicular thecal and granulosa cells were incubated for two hours in the presence or absence of human chorionic gonadotropin (hCG). After incubation, tissue cyclic AMP (cAMP) levels and medium content of progesterone (P), androstenedione (A) and estradiol-17 beta (E) were determined. A was the dominant steroid formed by the thecal cells, regardless if these were derived from small (diameter: 4-7.5 mm) or from large (diameter: 8-15 mm) follicles. Granulosa cells from small follicles formed minimal amounts of all steroids measured, while granulosa cells from large follicles produced considerable amounts of E in vitro. Thecal cells from both small and large follicles increased their production of cAMP in the presence of hCG. Steroid formation was significantly increased by hCG in thecal cells from large follicles only. Granulosa cells from large follicles responded to hCG in vitro with increased cAMP and steroid formation, while granulosa cells from small follicles appeared insensitive to hCG in vitro.

Adult↗
PubMed1984

Lipid metabolism in women with polycystic ovary syndrome: possible implications for an increased risk of coronary heart disease.

This study reports values of serum lipids, lipoproteins, and the relative fatty acid composition of lecithin and cholesterol ester in 20 women with typical polycystic ovary syndrome (PCO). These values were compared with values of 22 regularly menstruating women without clinical evidence of androgen excess. Higher levels of triglycerides in serum (P less than 0.05) and very low-density lipoproteins (P less than 0.01) and lower concentrations of free cholesterol in low-density lipoproteins (P less than 0.05) were found in the PCO women. In serum lecithin the PCO patients had higher palmitic and lower stearic acid levels compared with those of the normal women. This finding was interpreted as a reduction of the excretory capacity of the liver in the PCO group. No correlations between lipids and sex hormones were found. Body weights and blood pressures were higher in the PCO group. The results indicate that PCO women could be at increased risk for coronary heart disease, because an increased serum triglyceride level, body weight, and blood pressure are considered to be risk factors of coronary heart disease.

Adult↗
PubMed1984

Inherited salt sensitivity in normotensive humans as a cause of essential hypertension: a new concept.

The following concept of the pathogenesis of essential hypertension is proposed: there may be a continuous spectrum of noradrenergic sensitivity in normal subjects which is not only inherited but also modified later by different levels of psychological stress or by different types of behavior. The higher the noradrenergic sensitivity in a given subject, the greater the salt sensitivity and the greater the likelihood that hypertension will develop in later life if the usual high sodium-low potassium diet is consumed. Noradrenergic hypersensitivity may be linked to salt sensitivity in that it causes enhanced proximal tubular sodium reabsorption which is compensated for by pressure natriuresis. Enhanced pressure natriuresis requires persistently elevated blood pressure which leads to hypertension if maintained for many years. The phenomenon of salt sensitivity does not become apparent with a sodium intake of less than 50 mmol/day. Although enhanced noradrenergic sensitivity also persists with this low-sodium intake, salt-sensitive subjects are able to compensate for the enhanced rate of proximal tubular sodium reabsorption by reabsorbing less sodium at the distal tubules as compared with that reabsorbed by salt-resistant subjects. Enhanced noradrenergic sensitivity and enhanced proximal tubular sodium reabsorption, however, cannot be compensated for by fine-tuning aldosterone secretion while on the usual high sodium diet containing greater than 100 mmol/day. Under these conditions aldosterone secretion is already suppressed to its basal rate and cannot be suppressed more in salt-sensitive than in salt-resistant subjects. Therefore with the usual high sodium diet the enhanced rate of proximal tubular sodium reabsorption in salt-sensitive subjects is compensated for by enhanced pressure natriuresis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗