Extraction of estrogens by human perfused uterus. Effects of membrane permeability and binding by serum proteins on differential influx into endometrium and myometrium

The present study was undertaken to examine the extractions of estradiol, estrone, and estrone sulfate from the circulation of the human perfused uterus. The differential permeability of endometrial and myometrial vascular beds to estrogens was evaluated in uteri samples obtained during the proliferative and secretive phases of the menstrual cycle. The effects of binding by human serum proteins on estrogen influx into the endometrium and myometrium were also determined by the use of double-isotope, single-injection, timed tissue sampling techniques adapted to the extracorporeal perfusion of human uterus. Tritiated test estrogen was injected into the uterine artery as a mixture with 14C-butanol, a free diffusible reference substance. The influx of 14C-dextran (a membrane-impermeable compound) was used to test the aspecific influx from vasculature to extravascular space. Results show that in the human perfused uterus: (1) membrane permeability plays different roles in estrogen influxes between the endometrium and myometrium; (2) during the proliferative and secretive phase of the menstrual cycle the uterine microvessels are differently permeable to the free plus protein-bound estrogens; and (3) plasma proteins decrease the endometrial and myometrial uptakes of estrogens.     

Hypothalamic phospholipid liposomes in the treatment of the climacteric syndrome

Phospholipid liposomes have a dopaminergic effect on the human brain. Changes in prolactin and growth hormone secretion have been observed in humans given phospholipid liposomes. The authors have investigated the therapeutic efficacy of hypothalamic phospholipids in the menopausal syndrome. The study was an open trial on 37 outpatients treated with 1 and 2 ampoules i.m. of a preparation of phospholipids (in the form of unilamellar liposomes) for a period of six months. The therapeutic effects were assessed by means of the Hamilton rating scale, MMPI (Minnesota multiphasic inventory test), and a list of psychosomatic symptoms (LSP). In the patients no change in FSH, LH, PRL, or E2 secretion was observed, whereas the neurotic symptomatology appeared remarkably reduced.     

A 48-hour preservation of an isolated human uterus: endometrial responses to sex steroids

Human uteri were perfused with Krebs-Ringer bicarbonate-glucose buffer with and without estrogens and progesterone for a period of up to 48 hours to preserve a viable organ, which was responsive to hormones. Flow rates of 12 to 35 ml/minute per artery were fully distributed into the organ, with pressure values ranging from 80 to 120 mm Hg. Arteriovenous gradients of oxygen and carbon dioxide tensions as well as the levels of lactate, lactic dehydrogenase, and creatine kinase released in the perfusate, indicators of tissue ischemia or cell necrosis, showed a good preservation of the organ for up to 48 hours. The light- and electron-microscopic examinations of endometrial and myometrial tissues taken before and during perfusion confirmed this result. The extracorporeal perfusion of uteri with buffer containing estrogens plus progesterone exhibited secretive modifications of the proliferative endometrium, thus suggesting the viability of the organ and its responsiveness to sex steroids.     

Changes in the uterine vasculature during the menstrual cycle

The uterine vasculature of 15 uteri, which were hysterectomized for cervical cancer, has been studied. The removed uteri were immediately cannulated with four catheters inserted into the uterine arteries and veins and the vasculature was flushed with a saline-heparin solution. The vessels were clearly visualized by injection of radioopaque medium or of 5-10 ml prevulcanized natural latex, followed by tissue digestion. Histological studies of uterine specimens were also carried out for histomorphologic studies. The results show differences in the architecture of uterine vasculature, related to the cyclic hormonal changes. Most of the modifications occur in the radial and coiled arteries as well as in "venous lakes" of the endometrium.     

Verification of correct central venous catheter placement in the emergency department: comparison between ultrasonography and chest radiography

In 210 consecutive patients undergoing emergency central venous catheterization, we studied whether an ultrasonography examination performed at the bedside by an emergency physician can be an alternative method to chest X-ray study to verify the correct central venous catheter placement, and to identify mechanical complications. A prospective, blinded, observational study was performed, from January 2009 to December 2011, in the emergency department of a university-affiliated teaching hospital. Ultrasonography interpretation was completed during image acquisition; ultrasound scan was performed in 5 ± 3 min, whereas the time interval between chest radiograph request and its final interpretation was 65 ± 74 min p < 0.0001. We found a high concordance between the two diagnostic modalities in the identification of catheter position (Kappa = 82 %, p < 0.0001), and their ability to identify a possible wrong position showed a high correlation (Pearson’s r = 0.76 %, p < 0.0001) with a sensitivity of 94 %, a specificity of 89 % for ultrasonography. Regarding the mechanical complications, three iatrogenic pneumothoraces occurred, all were correctly identified by ultrasonography and confirmed by chest radiography (sensitivity 100 %). Our study showed a high correlation between these two modalities to identify possible malpositioning of a catheter resulting from cannulation of central veins, and its complications. The less time required to perform ultrasonography allows earlier use of the catheter for the administration of acute therapies that can be life-saving for the critically ill patients.     

Pre-implantation genetic testing in ART: who will benefit and what is the evidence?

Pre-implantation genetic diagnosis for aneuploidy testing (PGD-A) is a tool to identify euploid embryos during IVF. The suggested populations of patients that can benefit from it are infertile women of advanced maternal age, with a history of recurrent miscarriages and/or IVF failures. However, a general consensus has not yet been reached.After the clinical failure of its first version based on cleavage stage biopsy and 9 chromosome-FISH analysis, PGD-A is currently performed by 24 chromosome screening techniques on trophectoderm (TE) biopsies. This approach has been clearly demonstrated to involve a higher clinical efficiency with respect to the standard care, in terms of sustained pregnancy rate per transfer and lower miscarriage rate. However, data about PGD-A efficacy calculated on a per intention-to-treat basis, as well as an analysis of its cost-effectiveness, are still missing.TE biopsy is a safe and extensively validated approach with low biological and technical margin of error. Firstly, the prevalence of mosaic diploid/aneuploid blastocysts is estimated to be between 0 and 16 %, thus largely tolerable. Secondly, all the comprehensive chromosome screening (CCS) technologies adapted to, or designed to conduct PGD-A are highly concordant, and qPCR in particular has been proven to show the lowest false positive error rate (0.5 %) and a clinically recognizable error rate per blastocyst of just 0.21 %.In conclusion, there is a sufficient body of evidence to support the clinical application of CCS-based PGD-A on TE biopsies. The main limiting factor is the need for a high-standard laboratory to conduct blastocyst culture, biopsy and vitrification without impacting embryo viability.     

Financial impact in the Italian Health Service of laparoscopic versus laparotomic surgery for the treatment of ovarian cysts

To assess the cost of two procedures for the removal of ovariancysts, 200 pre-menopausal women were recruited for the surgicalremoval of ovarian cysts by laparoscopy (n = 100) and laparotomy(n = 100) according to case-control criteria. Patients operatedby laparoscopy (mean age ± SD 32.22 ± 9.98 years)and laparotomy (mean age ± SD 29.57 ± 6.62 years)for ovarian cysts (mean diameters ± SD 4.98 ±3.62 and 4.83 ± 2.78 cm) had a post-surgical hospitalstay of 3.12 ± 0.41 and 735 ± 1.08 days (P <0.001) respectively. The total rate of complications occurringin patients operated by laparoscopy was 9 versus 53% (P <0.001) of those operated by laparotomy; body temperature >38°Cwas recorded in 52/100 of patients operated by laparotomy versus6/100 of those operated by laparoscopy. The mean cost for eachpure surgical treatment performed by laparoscopy was US $498.17versus US $642.47 when it was performed by laparotomy (P <0.001). The laparo-scopic surgical approach is more expensivein the first 36 operations, thereafter becoming cheaper. Themean of the entire overall expenditure was US $1142.08 and US$2138.72 for laparoscopy and laparotomy (P < 0.001) respectively.The entire expenditure for laparoscopy is higher than laparotomyonly until eight operations. In conclusion, laparoscopy versuslaparotomy has resulted in a saving of US $14 4293 for 100 operationswhile the saving on entire costs was US $99 664.8. Submitted on June 28, 1995; accepted on November 14, 1995.     

Targeted drug delivery in gynaecology: the first uterine pass effect

The objective was to verify the hypothesis of a 'first uterine pass effect' or direct preferential vagina-to-uterus transport, suggested by the evidence of higher than expected uterine tissue concentrations after vaginal administration of progesterone; we used a human ex-vivo uterine perfusion model. A mixture of tritiated (3H) and unlabelled progesterone was applied to the cuff of vaginal tissue remaining attached to the cervix after hysterectomy. At the end of the perfusion period (up to 12 h), 3H and 14C radioactivity was measured in samples of uterine tissue. Tritiated water and [14C]dextran were tested to determine the extent of non-specific vagina-to-uterus transport (leaks). Finally, sections of uterine tissue exposed only to [3H]progesterone were prepared for autoradiography. By 4-5 h after application progesterone had diffused to the entire uterus and had reached a steady state; 4 h after application, progesterone concentrations reached 185 +/- 155 and 254 +/- 305 ng/100 mg of endometrial and myometrial tissue respectively. Endometrial extraction of progesterone was higher when the experiment was performed on uteri obtained during the luteal phase (280 +/- 156 ng/100 mg of endometrial tissue) than those removed during the proliferative phase of the menstrual cycle (74 +/- 28 ng/100 mg of endometrial tissue). These data demonstrate that a 'first uterine pass effect' occurs when drugs are delivered vaginally, thereby providing an explanation for the unexpectedly high uterine concentrations relative to the low serum concentration observed after vaginal administration. Hence, the vaginal route permits targeted drug delivery to the uterus, thereby maximizing the desired effects while minimizing the potential for adverse systemic effects.      

Implantation markers and endometriosis

The receptive phase of the endometrium seems to occur in close association with the appearance of pinopodes and endometrial integrins that may be activated by the interleukin-1 system (IL-1). Embryo attachment is the result of adhesion protein expression, and the invasion of the embryo is governed by proteolytic enzymes. Leukaemia inhibitory factor (LIF) is produced by natural killer lymphocytes that interact with the invading trophoblast. This may activate urokinase plasminogen activator (uPA) and gelatinase enzymes, which play a crucial role in trophoblast invasion. Oestrogen stimulates, while progesterone inhibits, LIF. The role of endometrial contractility in displacing human embryos from the Fallopian tube to the lumen cavity of the uterus or vagina in terms of pregnancy or wastage is still a matter of discussion. Endometriosis and its associated abnormal uterine contractions may be also linked to implantation failure. Unless new evidence emerges to indicate otherwise, it can be assumed that progesterone is, either in a direct (non-genomic: contractility) or indirect (genomic: decidualization) manner, the only determinant of endometrial priming necessary for embryo nidation.