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Biomedical subjects

J M Foidart

Publications and source records attributed to J M Foidart.

At least 109 records · Page 6Linked to original sources

[Transdermal replacement hormone therapy: a trend or an advantage?].

This review describes the clinical usefulness of transdermal hormone replacement therapy. This route of administration is particularly important in women with hypertriglyceridemia, in hypertensive postmenopausal women, in women who smoke or have an increased risk of biliary or liver disorder, for those who display a reduced glucose tolerance or in women who are at risk of thrombotic disorders. The avoidance of the "first passage effect" is ensured by the transdermal application of estrogen and probably explains the superiority of this route of steroid administration.

Administration, Cutaneous↗

[Cancer of the cervix uteri: analysis of the cost-benefit and efficacy of opportunistic screening versus organized screening].

Cervical cancer is the fourth cancer in women. It is the first malignancy for which mass population screening has been demonstrated to significantly reduce the mortality due to this disease. In Belgium, the mortality associated to cervical cancer decreased from 6 to 4 per 100,000 women-years from 1955-1959 to 1985-1989. European recommendations regarding cervical cancer screening are to perform a cervical smear each three years in women aged 25 to 65 years. In Belgium, while the Flemish region has decided to organize the cervical cancer screening according to the European recommendations, the screening in the French part of the country is essentially opportunistic. In this short review, the cost/benefit of the organized screening versus the opportunistic screening is discussed.

Adult↗

[The effects of labor induction on the progress of childbirth].

Labour induction has become a common practice. Given the significant number of induced deliveries carried out each year, it is important to know the consequences of this induction policy. The effects of labour induction on the childbirth are still the subject of considerable controversy. The increase of the caesarean and instrumental extraction rates has already been emphasized in previous studies. This article is based on an analysis of 10,045 deliveries carried out in the CHR Obstetrical Clinic of La Citadelle, between 1991 and 1997. The conclusions are instructive. Thus a departmental policy of setting an induction level of 35% will allocate 2/3 of the workload between 8:00 AM and 8:00 PM during the week, with a preponderance on Friday. The Caesarean rate is not increased but peridurals and recourse to instrumental extraction are more frequent.

Anesthesia, Epidural↗

[Surgical hysteroscopy or hysterectomy in the treatment of benign uterine lesions. What to choose in 1998?].

In the past, the treatment of benign uterine lesions required, in many instances, a hysterectomy. These days, most cases can be successfully treated by hysteroscopy. To be reliable, this technique must lead to a significant reduction in the number of hysterectomies performed for benign uterine lesions. The electroresection technique is preferred to that using the Nd-YAG laser because of its lower cost and its equivalent efficacy. By using the uterine perfusion pump device, the risk of resorption syndrome can be reduced to its minimum. Submucosal myomas < 1 cm, benign endometrial hyperplasia and adenomyosis are the commonest benign lesions treated. Dysfunctional uterine bleeding can also be treated by an endometrectomy. A preoperative workup includes a transvaginal ultrasound and a biopsy. This ensures that only benign lesions that are accessible to a hysteroscopy will be submitted to this technique and that no cases of endometrial cancer or atypical hyperplasia would be ignored. This study presents 270 cases of operative hysteroscopy with a follow-up to 4 years. 82.8% of myomatous lesions were treated with success. The results for patients with benign endometrial polyps or benign endometrial hyperplasia are also excellent with only 4.6% and 5.6% rate of secondary surgery respectively. Adenomyosis does not appear to be a good indication for hysteroscopy as only 37% of patients did not need a definitive hysterectomy. Rates of operative complications (post-operative bleeding, uterine perforation, resorption syndrome and difficulty of access) are acceptable and get less frequent as the surgeon experience increases.

Biopsy↗

Alteration of interendothelial adherens junctions following tumor cell-endothelial cell interaction in vitro.

The integrity of the vascular endothelium is mainly dependent upon the organization of interendothelial adherens junctions (AJ). These junctions are formed by the homotypic interaction of a transmembrane protein, vascular endothelial cadherin (VE-cadherin), which is complexed to an intracellular protein network including alpha-, beta-, and gamma-catenin. Additional proteins such as vinculin and alpha-actinin have been suggested to link the VE-cadherin/catenin complex to the actin-based cytoskeleton. During the process of hematogenous metastasis, circulating tumor cells must disrupt these intercellular junctions in order to extravasate. In the present study, we have investigated the influence of tumor cell-endothelial cell interaction upon interendothelial AJ. We show that human breast adenocarcinoma cells (MCF-7), but not normal human mammary epithelial cells, induce a rapid endothelial cell (EC) dissociation which correlates with the loss of VE-cadherin expression at the site of tumor cell-EC contact and with profound changes in vinculin distribution and organization. This process could not be inhibited by metalloproteinase nor serine protease inhibitors. Immunoprecipitations and Western blot analysis demonstrate that the overall expression of VE-cadherin and vinculin as well as the composition of the VE-cadherin/catenins complex are not affected by tumor cells while the tyrosine phosphorylation status of proteins within the complex is significantly altered. Our data suggest that tumor cells modulate AJ protein distribution and phosphorylation in EC and may, thereby, facilitate EC dissociation.

Adenocarcinoma↗

Production and activation of matrix metalloprotease-9 (MMP-9) by HL-60 promyelocytic leukemia cells.

Human promyelocytic HL-60 cells have been used as a model of acute leukemia to investigate the expression and the regulation of matrix metalloproteases (MMPs), known to contribute to the degradation of extracellular matrix components. As shown by gelatin zymography, HL-60 cells constitutively released significant amounts of proMMP-9 (92 kDa) and moderate amounts of proMMP-2 (72 kDa). Furthermore, casein zymography confirmed the presence of serine proteases in the form of pro-urokinase. Activation of proMMP-9 was dependent on the plasminogen activator/plasmin (PA/plasmin) system and was inhibited by aprotinin. MMP-9 was only detected in cellular extracts or conditioned media incubated with HL-60 cells, indicating that cells are essential to the activation process. Addition of plasminogen increased by 3-fold the basal invasive rate of these cells across a matrigel layer (2.1% versus 0.7% in control cells after 4 h of incubation). Taken together, these results indicate that HL-60 cells exhibit an autocrine activation mechanism of proMMP-9 via the PA/plasmin system and that activation of proMMP-9 increases their invasive potential.

Aprotinin↗

Involvement of PA/plasmin system in the processing of pro-MMP-9 and in the second step of pro-MMP-2 activation.

Pro-MMP2 activation is a two-step process resulting in (1) an intermediate 64 kDa form generated by the MT1-MMP activity, and (2) a mature 62 kDa form. Addition of plasminogen to HT1080 cells cultured under various conditions, or to their membrane preparation, induced a complete conversion of the intermediate MMP-2 form to the mature one, and processing of pro-MMP-9. The pro-MMP-2 activation was inhibited by plasmin inhibitors and anti-uPA antibody. These results provide evidence for involvement of the PA/plasmin system in the second step of MMP-2 activation.

Enzyme Activation↗

Localization of laminin, fibronectin, E-cadherin, and integrins in endometrium and endometriosis.

OBJECTIVE: To compare the localization of adhesion proteins (laminin and fibronectin) and their receptors of the integrin family in endometriosis and endometrium. DESIGN: An immunohistochemical study. SETTING: University Hospital, Department of Gynecology and Department of Cell Biology. PATIENT(S): Eighteen endometriosis patients undergoing laparoscopy for pain or infertility and nine control patients undergoing laparoscopy for sterilization or hysterectomy. MAIN OUTCOME MEASURE(S): The expression of adhesion glycoproteins (laminin and fibronectin), their receptors alpha 1 beta 1, alpha 2 beta 1, alpha 3 beta 1, alpha 5 beta 1, and alpha 6 beta 1, and E-cadherin was determined by immunohistochemistry on frozen sections. RESULT(S): The distribution of both adhesive glycoproteins, laminin and fibronectin, and their receptors was identical in endometriosis and endometrium. Fibronectin receptors (alpha 4 beta 1, alpha 5 beta 1) displayed distinct expression patterns in endometrium and endometriosis. No endometrial glands showed positive staining for the alpha 5 chain, whereas this integrin subunit was detected in almost all endometriotic lesions. The integrin alpha 4 chain was present in all endometriotic glands but was absent from endometrial glands in the proliferative phase of the cycle. CONCLUSION(S): No difference in cell adhesion molecule localization nor receptors was observed between endometriotic and endometrial samples, except for fibronectin receptors. Their expression persisted around endometriotic glands but not in endometrium. These results suggest that fibronectin receptors could play a role in the persistence of endometriotic lesions, despite menstruation in corresponding eutopic endometrium.

Adult↗

Expression of stromelysin-3 in the human placenta and placental bed.

Human placentation is mediated by fetal trophoblastic cells which penetrate into the decidualized uterine endometrium. Trophoblast invasion requires the precisely regulated secretion of specific proteinases able to degrade the endometrial basement membranes and extracellular matrix. To document further the involvement of these proteinases during human placentation, we evaluated in vivo the expression of stromelysin-3, a member of the metalloproteinase family, during the first and third trimesters of pregnancy, by means of immunohistochemistry, in situ hybridization and Northern blot analysis. Human extravillous trophoblasts invading the maternal decidua produced stromelysin-3 during both, the first and third trimesters of pregnancy, but to a lesser extent during the latter. In floating villi, stromelysin-3 expression was restricted to the syncytiotrophoblasts that line intervillous vascular spaces. In conclusion, stromelysin-3 is expressed by differentiated, non-proliferative villous and extravillous trophoblastic cells in early and late placental beds and villi, and its pattern of expression evolves during pregnancy. Our observations suggest that stromelysin-3 could play a role in human placentation.

Blotting, Northern↗

Impact of percutaneous oestradiol gels in postmenopausal hormone replacement therapy on clinical symptoms and endometrium.

OBJECTIVE: To compare the effects on endometrium, climacteric symptoms and the menstrual cycle, and the clinical and biological tolerance of two percutaneous oestradiol gels used as hormone replacement therapy. DESIGN: A large open randomised multicentre study. SETTING: France and Belgium. PARTICIPANTS: Two-hundred and fifty-four women with an intact uterus and who had experienced a natural menopause received either Oestrogel (n = 126) or Estreva, a new formulation of oestradiol gel (n = 128), (1.5 mg of oestradiol/day) for the 24 first days of each calendar month during six consecutive months. Nomegestrol acetate (Lutenyl), a norprogesterone derivative, was administered (5 mg/day) from day 11 to day 24 of each oestradiol cycle. MAIN OUTCOME MEASURES: Examination of endometrial biopsies taken before treatment and between days 18 and 24 of the last treatment cycle, climacteric symptoms assessed using a modified Kupperman index, control of menstrual cycle evaluated by diary cards, and clinical and biological tolerance. RESULTS: Both treatments lowered the frequency and intensity of hot flushes and the global Kupperman index. 96% of the cycles were followed by withdrawal bleeding. Breakthrough bleeding or spotting resulted in premature discontinuation of treatment in one volunteer. Mastodynia occurred in 20 women and contributed to the premature termination of treatment in three of them. Endometrial biopsies taken at the end of treatment showed identical histologies in both groups, with a secretory pattern in the majority of women, and absence of hyperplasia. CONCLUSIONS: This trial confirmed that, when the two oestradiol gels tested were administered cyclically with nomegestrol acetate to postmenopausal women, they were well tolerated, effective and suitable for the treatment of oestrogen deficiency syndrome.

Administration, Cutaneous↗

Loss of type IV collagen alpha 5 and alpha 6 chains in human invasive prostate carcinomas.

Type IV collagen, a major component of basement membranes, is organized in a network responsible for the mechanical resistance of the basement membranes. It also plays a key role in epithelial cell adhesion to basement membranes. This study was designed to investigate the distribution of type IV collagen alpha-chains in normal, preneoplastic, and malignant prostate basement membranes. For this purpose, immunohistochemistry using specific antibodies raised against the different alpha-chains of type IV collagen was performed in eight normal samples, six prostatic intraepithelial neoplasia, and 20 malignant lesions of the prostate. Our results demonstrate the presence of the "novel" alpha 5 (IV) and alpha 6 (IV) chains along with the "classical" alpha 1 (IV)/alpha 2 (IV) chains in the basement membrane of the normal prostate gland. The alpha 3 (IV) chain was never detected in any prostate specimen. Prostatic intraepithelial neoplasia showed a similar immunostaining pattern to that found in normal glands. In cancer gland basement membranes, we demonstrate for the first time a specific loss of the alpha 5 (IV) and alpha 6 (IV) chains, whereas the classical alpha 1 (IV) and alpha 2 (IV) chains were consistently exhibited. Additionally, type VII collagen colocalized with alpha 5 (IV) collagen chain, and these two proteins, which were always observed in normal and prostatic intraepithelial neoplasia gland basement membranes, were lost in invasive carcinoma basement membranes. This observation raises questions about the possible association or cooperation between alpha 5 (IV)/alpha 6 (IV) chains and anchoring fibrils in prostate glands basement membrane.

Adenocarcinoma↗

[Precancerous states of the endometrium: hormonal aspects].

The two types of endometrial carcinomas are preceded by precancerous lesions. Type I endometrial carcinomas are most commonly encountered in perimenopausal women with the classical risk factors associated with estrogen exposure: obesity, multiparity, diabetes, estrogen treatment, ... Hyperplasia (simple, followed by complex forms without cellular atypias and subsequently by complex hyperplasias with cellular transformation) precede such cancers. Estrogens exert a promoting effect on these lesions but do not initiate them. Progesterone and progestins exert a preventive and protective effect. However, the progressive loss of steroidal receptors is correlated to the progression of tissular anomalies and to the onset of cytogenetic anomalies and to mutations of p53 anti-oncogene. The preventive role of progestin is well established, but their curative beneficial effect on atypical precursors forms of endometrial cancers and on endometrial carcinomas remains controversial. The second type of endometrial cancer appears during the postmenopause and is characterized by an increased invasiveness and a poor prognosis, devoid of identifiable risks factors, these aggressive cancers are not preceded by hormone-sensitive precancerous lesions, but by an intra-epithelial endometrial carcinoma. This lesion appears most often in an atrophic endometrium. Finally, the two types of precancerous states are characterized by distinct gene anomalies suggesting two different pathogenic mechanisms of cancerisation.

Endometrial Neoplasms↗