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Biomedical subjects

L Hamberger

Publications and source records attributed to L Hamberger.

At least 91 records · Page 5Linked to original sources
PubMed1990

[Sonography in breast diagnosis].

In a prospective study of 235 tissue masses verified histologically, we examined the diagnostic contribution of ultrasound in comparison to mammography. When the two methods were combined, 96.8% of all malignant neoplasms could be diagnosed correctly. Most (90.5%) were found by mammography alone and 4.8% were detectable by ultrasonography but not by mammography. Despite relatively good results in the evaluation of solid masses, it is not advisable to omit tissue examination. The superiority of ultrasound over mammography in the diagnosis of cystic lesions could lead to a significant reduction in needle aspirations and biopsies.

Adenofibroma↗
PubMed1989

Technical and clinical aspects of ultrasound guided oocyte recovery.

In our experience, as well as that of many other IVF groups, transvaginal, ultrasound-guided follicle aspiration is less invasive and comparable to, or better than laparoscopy with regard to the efficiency of oocyte recovery and safety. For these reasons, we believe that ultrasound-guided follicle aspiration will gradually become the method of choice if the only purpose is to retrieve oocytes.

Female↗
PubMed1989

Characterization of a monoclonal antibody which inhibits the biological activity of human chorionic gonadotrophin in human corpora lutea.

In the present study a murine monoclonal antibody (MCA), directed against human chorionic gonadotrophin (HCG), was investigated in vitro utilizing human corpora lutea (CL). The CL were excised from women of fertile age undergoing various gynaecological operations. The CL specimens were cut into pieces and incubated in standard medium for 2 or 4 h in the presence of HCG, luteinizing hormone (HLH) or prostaglandin (PG) E2 alone or in combination with the MCA directed against HCG. After incubation, the tissue levels of cyclic adenosine 3',5' monophosphate (cAMP) and the media contents of progesterone (P) were determined. HCG, HLH and PGE2 stimulated both cAMP and P formation in CL of all ages, while the MCA alone had no effect on these parameters. The MCA, however, effectively counteracted the stimulatory effect of HCG on both cAMP and P formation on a 1:1 molar basis. This antagonistic effect was clearly reversible and could be overcome by increasing the HCG concentrations. The stimulatory effect of HLH and PGE2, on the other hand, was not influenced by the antibody, even when administered at high concentrations. These in-vitro data show that the MCA studied effectively counteracts the stimulatory effect of HCG on human luteal tissue with high specificity.

Adult↗
PubMed1989

Refractoriness to follicle-stimulating hormone in rat ovarian granulosa cells--a concentration- and time-dependent phenomenon.

Granulosa cells from pre-ovulatory ovarian follicles of rats were exposed, in vitro, to one or two pulses of follicle-stimulating hormone (FSH) in a superfusion apparatus. The superfusate was analysed for cyclic adenosine-3',5' monophosphate (cAMP) and steroids. In experiments with two consecutive FSH pulses, the response to the second pulse (100 ng/ml) was inversely related to the concentration of the first FSH pulse (2.5-100 ng/ml). Within certain limits, a lower total amount of cAMP and progesterone was accordingly released in response to the two FSH pulses when the concentration of the first pulse was increased. This refractoriness declined within a few hours as shown in experiments with extended pulse intervals. Two short and separate FSH pulses also evoked a higher combined response than did a single long FSH pulse lasting the whole time period. In these cases the cells thus responded with a lower total cAMP and progesterone release when exposed to a higher amount of FSH. Clinical trials on i.m. versus pulsatile i.v. FSH administration to anovulatory women have shown a similar relationship between FSH dose and effect, though other parameters were measured than those in the present study.

Animals↗
PubMed1989

Endometriosis: poster and literature review.

Posters on endometriosis at the International Symposium on Endocrine Therapy are reviewed and discussed. Mechanisms of various treatments are discussed, with a note on the possible immunological basis of endometriosis.

Endometriosis↗
PubMed1988

Sonographic techniques in human in-vitro fertilization programmes.

The value of ultrasound in programmes of in-vitro fertilization is discussed. In order to reach the ovaries, the transvesical route was first introduced, and proved less invasive than laparoscopy. The periurethral route has also been used. The transvaginal approach, especially using a vaginal transducer with an attached needle guide, has attracted many IVF groups and is widely used today. Details of this method are presented. Ultrasound has also been used to assist in the replacement of embryos into the uterus, and the various methods are described.

Female↗
PubMed1988

Prolactin and gonadotrophin interactions on progesterone formation in cultured human granulosa cells.

Human granulosa cells were isolated from preovulatory follicles during cycles stimulated with HMG-HCG or clomiphene-HMG-HCG or from unstimulated cycles. The cells were cultured for 6-8 days in medium M199 containing fetal calf serum under 5% CO2 in air. Highly purified human prolactin and human chorionic gonadotrophin were added alone or in combination to the cultures, and the content of steroids in the medium was measured every second day, utilizing conventional RIA techniques. In the presence of HCG the formation of progesterone (P) increased 3-5-fold over the control level with maximal effect after 4 days. In cells derived from clomiphene-HMG-HCG stimulated cycles, prolactin per se did not influence basal P formation but reduced the stimulatory effect of HCG. This was only seen in granulosa cells from follicles greater than 20 mm in diameter. In experiments with Forskolin, an adenylate cyclase activator, P formation was stimulated and the stimulation was counteracted by the concomitant presence of prolactin, indicating that prolactin did not interfere with the LH-HCG receptor. In cells from smaller follicles, or in cells from follicles aspirated from the natural cycle prior to the endogenous LH peak, P formation was stimulated by HCG but the addition of prolactin did not reduce this stimulatory effect. The results are discussed in relation to earlier reports on prolactin effects in vitro both on laboratory animals and human material.

Cells, Cultured↗
PubMed1988

Luteotropic effects of prostaglandin E2 on the human corpus luteum of the menstrual cycle and early pregnancy.

Human corpora lutea (CL) of the menstrual cycle and early pregnancy were excised at operation, cut into pieces, and incubated or superfused in the presence of hCG or prostaglandin (PG) E2. After incubation, the tissue levels of cAMP and the medium concentrations of progesterone (P) were determined, while the concentration of P was analyzed after superfusion. PGE2 stimulated cAMP formation in CL from all phases of the menstrual cycle as well as from early pregnancy and caused an increase in P formation in CL from the early and midluteal phases of the menstrual cycle as well as from early pregnancy. A difference was found in the latency, the lag phase until maximal response, and the duration of response between the effects of PGE2 and hCG on both cAMP and P formation. Thus, the effect of PGE2 started more rapidly and was of shorter duration than that of hCG. The stimulatory effect of PGE2 on CL from early pregnancy was of the same magnitude as that of CL from the menstrual cycle. On the other hand, hCG had less stimulatory effect on cAMP and P formation in CL from early pregnancy compared to CL from the menstrual cycle. We conclude that PGE2 stimulates P and cAMP formation in isolated human CL from all phases of the menstrual cycle as well as in early pregnancy, indicating a luteotropic effect of this PG.

Adult↗
PubMed1988

Metabolism of 7,12-dimethylbenz(a)anthracene by different types of cells in the human ovary.

1. The metabolism of 7,12-dimethylbenz(a)anthracene (DMBA) by primary cultures of human ovarian cells has been studied to identify the cell type(s) responsible for biotransformation of this carcinogen. The rate of DMBA metabolism was maximal in granulosa cells prestimulated in vivo with antiestrogen, hMG (human menopausal gonadotropin) and hCG (human chorionic gonadotropin), i.e., treatments required for maximal oocyte maturation and, thus, granulosa cell proliferation. In cells from unstimulated ovaries, the metabolism was maximal in granulosa-lutein cells isolated from corpus luteum. 2. Steroid (progesterone and estradiol) levels were determined in the spent culture media or in media in parallel with DMBA metabolism to find out whether elevated steroid levels in vivo are required for the rapid metabolism of DMBA. In granulosa cell cultures from stimulated cycles, the concentrations of both progesterone and estradiol were at least 2 or 3 times higher, respectively, than in any of the other cell types tested. In cell cultures derived from unstimulated ovaries, the progesterone and estradiol concentrations were highest in granulosa-lutein cell cultures. 3. Incubations of granulosa cells with DMBA in the absence or presence of gonadotropins, testosterone or anti--hCG were performed to investigate possible hormonal requirements for the cytochrome P-450 system(s) which metabolize DMBA. No change in the rate of metabolism was obtained with follicle stimulating hormone (FSH), luteinizing hormone (LH), hCG or testosterone. However, anti-hCG increased this activity about 70%, indicating a negative modulatory role of hCG on DMBA mono-oxygenase activity in human granulosa cells. 4. DMBA mono-oxygenase activity in cell cultures was inhibited about 95% by alpha-naphthoflavone (ANF), an inhibitor of certain cytochrome P-450-catalysed activities. Benzo(a)pyrene (BP) was metabolized at the same rate as DMBA in granulosa cell cultures.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1987

Local prostaglandin F2 alpha injection for termination of ectopic pregnancy.

In nine women with unruptured ectopic pregnancy, prostaglandin F2 alpha was injected under laparoscopic control into the affected oviduct and in eight patients also into the ovary containing the corpus luteum. Termination of the pregnancy was achieved in all cases (in one at the second attempt), without complications. Fertility after this procedure needs to be compared with that after conventional surgery.

Abortifacient Agents↗
PubMed1987

Does a gradually decreasing menstrual blood loss (MBL) in women wearing a Cu-IUD indicate a risk for an accidental pregnancy?

In three separate series, comprising 71 women using either a Gravigard, a Nova-T or a Multiload contraceptive device, the menstrual blood loss (MBL) was quantitatively assessed before and after insertion of each respective IUD. In three women, an involuntary pregnancy was registered with the IUD in situ. In these three women a successively diminishing MBL was registered during the last 3 months before conception, while none of the remaining women included in the series experienced any accidental pregnancy or any reduction of the MBL. Thus, this report emphasizes the potential risk for an accidental pregnancy in women wearing a Cu-IUD if successively diminishing MBLs are observed.

Adult↗
PubMed1987

On the specificity of prostaglandin and steroid induced inhibition of 3H-proline incorporation in the human follicular wall.

Experiments were carried out to elucidate whether the previously reported inhibitory effect of prostaglandin (PG) E2 on 3H-proline incorporation into total protein of specimens from the isolated preovulatory human follicular wall could be exerted also by other prostanoids. Moreover, investigations were designed to explore if the previously documented inhibitory effect of steroids on 3H-proline incorporation could be mediated by endogenously formed PGs. Tissue specimens from the apical wall of follicles were incubated in the presence of PGF2 alpha, 6-keto-PGF1 alpha, progesterone (P) or 17 beta-estradiol (E2). The steroids were added alone or in combination with the PG synthetase blockers, indomethacin or 5, 8, 11, 14-eicosatetraynoic acid. Following incubation with 3H-proline for 2-4 h, the incorporated radioactivity was determined. PGF2 alpha and 6-keto-PGF1 alpha had no effect on 3H-proline incorporation. Both P and E2 induced a significant decrease of 3H-proline incorporation in preovulatory follicles, whereas similar effects in unripe follicles were statistically significant only for P. The steroid effects were not influenced when blockers of PG synthesis were added concomitantly. It is concluded that among the "classical" PGs PGE2 has a unique effect on collagen metabolism in the human follicular wall. E2 and especially P have a similar inhibitory effect on collagen formation as reflected by measurements of 3H-proline incorporation, an effect which does not appear to be primarily mediated by endogenous PGs.

Collagen↗
PubMed1987

Catecholamine content and adenylate cyclase activity in corpora lutea of different ages of the PMSG-treated immature rat.

The catecholamine content and adenylate cyclase response were studied in a well-characterized corpus luteum model, where ovulation was induced by treatment of prepubertal Sprague-Dawley rats with pregnant mare's serum gonadotropin. The luteal content of noradrenaline, determined with HPLC, was constant during the first 7 days of pseudopregnancy, followed by a 3-fold increase in older corpora lutea. No detectable amounts of dopamine were found, while trace amounts of adrenaline were found in a few cases. The increase in noradrenaline content was not associated with a changed sensitivity of luteal adenylate cyclase to catecholamines. The response to adrenaline was maximal in 3-day-old corpora lutea, whereafter a decrease was seen. The significance of the increased endogenous levels of noradrenaline at the end of pseudopregnancy is at present unknown. However, the fact that the increase in noradrenaline occurs a few days before spontaneous luteolysis is of special interest, since it has been suggested that an adrenergic innervation is a prerequisite for the antigonadotropic effect of prostaglandin F2 alpha in the human corpus luteum.

Adenylyl Cyclases↗
PubMed1987

The regulatory role of FSH in steroid formation by luteinized human granulosa cells in culture.

Granulosa cells were aspirated from human pre-ovulatory follicles following a combined clomiphene-gonadotrophin stimulation in an in-vitro fertilization (IVF) programme. The cells were cultured for 8 days in medium M199 containing 10% bovine fetal calf serum under 5% CO2 in air. Pure human FSH and human LH were added alone or in combination to the culture in various concentrations and the progesterone (P) and oestradiol-17 beta (E2) levels in the medium were measured every second day by a conventional RIA technique. In the presence of FSH or LH the formation of P increased 2- to 3-fold with the pronounced effect after 4 to 6 days in culture. Addition of testosterone (T) (3 X 10(-7) M) to the culture medium affected neither basal nor gonadotrophin stimulated P formation. In this system, only minute amounts of E2 were formed and neither FSH nor LH stimulated its formation. When the medium was fortified with T, basal E2 formation increased 50- to 100-fold. FSH further stimulated this conversion significantly after 6 and 8 days of culture, while LH had no significant influence.

Cells, Cultured↗
PubMed1987

Perinatal origin of adult self-destructive behavior.

The study was undertaken to test whether obstetric procedures are of importance for eventual adult behavior of the newborn, as ecological data from the United States seem to indicate. Birth record data were gathered for 412 forensic victims comprising suicides, alcoholics and drug addicts born in Stockholm after 1940, and who died there in 1978-1984. The births of the victims were unevenly distributed among six hospitals. Comparison with 2,901 controls, and mutual comparison of categories, showed that suicides involving asphyxiation were closely associated with asphyxia at birth, suicides by violent mechanical means were associated with mechanical birth trauma and drug addiction was associated with opiate and/or barbiturate administration to mothers during labor. Irrespective of the mechanism transferring the birth trauma to adulthood--which might be analogous to imprinting--the results show that obstetric procedures should be carefully evaluated and possibly modified to prevent eventual self-destructive behavior.

Adult↗
PubMed1987

[Value of microhematuria, urine cytology, TPA and neopterin in the after care of patients with bladder tumors].

Tumor recurrences were observed 70 times in 715 cystoscopies performed in 253 patients. The sensitivity of microhematuria to detect a tumor recurrence was 61%, the specificity 84%. The sensitivity of microhematuria increased to 90% in Tis and T2 tumors. Urine cytology showed a specificity of 100% and a sensitivity of only 43%. The specificity and sensitivity of TPA was only 58% and 41%, respectively, the latter increased to 80% in Tis. 60 patients with proven tumor recurrence showed an increase of neopterin with higher tumor stage. In tumors of stage T2 and Tis serum neopterin was raised in 90% and urine neopterin in 75%. Based on these results cystoscopy, exfoliative urinary cytology and urine analysis are obligatory in the follow-up of patients with superficial bladder cancer. Because of the low specificity (29-41%) TPA and neopterin are not suitable for follow-up.

Biopterins↗