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N Perrot

Publications and source records attributed to N Perrot.

At least 19 recordsLinked to original sources
PubMed2005

[Preeclampsia and antiphospholipid syndrome. Uterine artery Doppler evaluation].

INTRODUCTION: Women with persistently high resistance in uterine arteries have an increased risk of the subsequent development of preeclampsia. Doppler investigation provides a non-invasive method for the study of the uteroplacental blood flow. In pregnant women the antiphospholipid syndrome is associated to an increased risk of preeclampsia and complications related to uteroplacental insufficiency, and the role of uterine artery Doppler is discussed. CURRENT KNOWLEDGE AND KEY POINTS: In normal pregnancy, impedance to flow in the uterine arteries decreases with gestation, as the likely consequence of the physiologic change of spiral arteries into low-resistance vessels. In women with preeclampsia or related complications, the abnormal persistence of high resistance to flow in the uterine arteries correlates with maternal and neonatal outcome. In one study including patients with antiphospholipid syndrome, a high resistance index in the uterine arteries at 22-24 weeks gestation strongly predicted the subsequent development of preeclampsia. In another study including patients with lupus anticoagulant, persistent bilateral notches at 22-24 weeks gestation may identify preeclampsia and fetal growth restriction with a high sensitivity, specificity, positive and negative predictive value. The treatment may improve the uteroplacental blood flow and is a possible confounding factor which needs further evaluation. FUTURE PROSPECTS AND PROJECTS; In patients with antiphospholipid antibodies a higher impedance has been observed in the uterine artery, suggesting a possible vascular dysfunction precluding to impaired trophoblastic invasion and placental thrombosis, as probable mechanisms in the complications. If confirmed, these findings might have important implications for the management of these patients.

Adult↗
PubMed2003

[Uteroplacental haemodynamics and uterine artery Doppler practice at 12 weeks gestation].

Last years, feasibility and possible interest of uterine artery Doppler during the third month of gestation were confirmed. Doppler flow velocity waveforms can be obtained and assessed in both uterine arteries using abdominal ultrasonography at 12-14 weeks' gestation. The no notch group (one third of women) has a low risk for hypertension, intra-uterine growth restriction, abruptio placentae. The "protecting" effect of the absence of uterine artery notch is as high as this physiological change occurs earlier.

Arteries↗
PubMed2003

[Contribution of ultrasonography in the diagnosis of ectopic pregnancy].

High-resolution endovaginal sonography has considerably improved ectopic pregnancy imaging. In conjunction with serum hCG measurements, it allows early detection of ectopic pregnancy (EP) and has significantly reduced the morbidity and the mortality of this disease. The major sonographic finding is the uterine vacuity, the diagnosis of ectopic pregnancy is quite sure in case of absence of intra-uterine pregnancy (IUP) associated with serum hCG above 1500 mUi/ml. Conversely, the presence of IUP excludes practically the diagnosis of EP, but IUP must be distinguished from a pseudosac. The visualization of an ectopic sac that contains an embryo or a yolk sac clearly allows the diagnosis of EP, but its sensitivity is only 25%. The most common sonographic finding is a hematosalpinx, which looks like an echogenic adnexal mass, next to the ovary containing the corpus luteum. Color Doppler is useful to enhance ectopic trophoblastic flow, but it is only a complementary technique of endovaginal sonography. Finally, if the first sonography is inconclusive, a follow-up examination must be performed 2 or 4 days later.

Chorionic Gonadotropin↗
PubMed2002

[Menorrhagia after age 40. Contribution of ultrasonic examination].

Menorrhagia after age 40 can have functional, general, local, or organic reasons. The most frequent are: submucous myomas, adenomyosis, polyps. Submucous myomas: a transvaginal scan (TVUS) specifies the type of myoma according to its situation within the uterine cavity: intracavitary myoma or submucous. A transvaginal scan is performed to assess myomas before operative HSC. There are three criteria to check: myomas diameter must be less than 5 cm; 5 mm or more of normal myometrium should be present between myoma and external wall; the myoma must not be in contiguity with a subserosal myoma. Uterine adenomyosis is a common gynecologic condition that is characterized by the presence of heterotopic endometrial glands and stroma in the myometrium with adjacent smooth muscle hyperplasia. Pathology may be proximal or distal, focal or diffuse. Transvaginal US shows: cystic dilatation of heterotopic glands, heterogeneity of the myometrial echotexture, antero-posterior asymmetry of the uterus. TVUS has a sensitivity of 62 to 89% and a specificity of 89 to 96%. Polyps are most often hyperechoic: this makes the diagnosis more difficult in luteal phase; Power Doppler shows the vascular central pedicle. TVUS has a sensitivity of 75%. The polyps smaller than 3 mm are not visible in a reliable way without the help of a contrast media in the cavity.

Adenomyoma↗
PubMed2001

Assessment of Fallopian tube patency by HyCoSy: comparison of a positive contrast agent with saline solution.

OBJECTIVE: To compare the efficiency of air-filled albumin microspheres (Infoson) with saline solution in determining Fallopian tube patency during hysterosalpingo contrast sonography (HyCoSy). METHODS: This was a prospective randomized multicenter study with a sequential design. Over a 10-month period, 23 patients (mean age, 33 years) referred for infertility were examined by HyCoSy (saline or Infoson) before conventional hysterosalpingography (Iopamiron 370), performed during the same session. Contrast agents were administered through a 5-F Ackrad balloon catheter inserted transcervically into the uterine cavity. HyCoSy was performed with a 7-MHz transvaginal probe using both B-mode and color Doppler, and tubal patency was demonstrated by the appearance of contrast agent in the peritoneal cavity near the ovaries. Data were registered for each patient during the examination and the results were monitored by sequential analysis. RESULTS: Mean volumes of contrast injections were 35.3 mL of saline, 14.4 mL of Infoson, and 13.8 mL of Iopamiron 370. Infoson-enhanced HyCoSy provided a significantly larger (P = 0.006) number of correct diagnoses (20/22 Fallopian tubes) than did saline HyCoSy (12/24 Fallopian tubes), and the same number as that achieved by hysterosalpingography. CONCLUSION: A positive ultrasound contrast agent appears to be more efficient than saline solution at determining Fallopian tube patency in infertile women by means of HyCoSy, and as efficient as an iodinated contrast agent in the same population explored by HSG. HyCoSy could be used to screen infertile women, thereby avoiding the use of iodinated contrast medium and exposure to ionizing radiation during conventional HSG in patients with patent Fallopian tubes.

Adult↗
PubMed1998

Intradural extramedullary spinal canal secondary neoplasms: MR findings in 30 patients.

The purpose of this study was to describe magnetic resonance findings of intradural spinal canal secondaries and to select the best way of investigating this condition. Thirty patients with a known malignancy [breast carcinoma (n = 14), lung carcinoma (n = 10), other sites (n = 6)] and unexplained neurologic signs were studied with pre- and post-contrast T1-weighted images and T2-weighted images. Cerebrospinal fluid cytology was available in 16 patients and positive in 11 patients. In all the patients, post-contrast T1-weighted images demonstrated abnormal enhanced lesions. Most of them were nodular, located on the conus medullaris and the cauda equina. Few lesions appeared at the thoracic or cervical levels, as nodular or thin areas of enhancement. Pre-contrast T1-weighted sequences failed or were equivocal to detect the lesions. Eighteen of 30 patients had cerebral metastases. Fourteen had osseous metastases. In conclusion, post-contrast T1-weighted sequence is the optimal modality for the diagnostic of intradural spinal canal metastases. Axial and coronal images may be a useful adjunct to precise anatomic changes. T1-weighted and T2-weighted sequences remain necessary when further information is expected on vertebra or soft tissue.

Breast Neoplasms↗
PubMed1997

[Sonohysterography: a new study method of the uterine cavity: evaluation of 84 cases and comparison to hysteroscopy].

Sonohysterography versus hysteroscopy: the assessment of the uterine cavity: a series of 84 cases. We study indications, advantages, limits of a technic of investigation of uterine cavity: sonohysterography. Our results show that sonohysterography is as effective as hysteroscopy in the diagnosis of intrauterine conditions. It is painless, no time consuming. There is no adverse effects and it is helpful in the diagnosis of intrauterine abnormality as a complement of transvaginal scanning.

Endometrium↗
PubMed1996

[Ultrasono-hysterography: techniques and indications].

Sonohysterography consists in injecting a saline solution into the uterine cavity and performing transvaginal sonography. The purpose of this procedure is the pre-operative assessment of intracavitary anomalies, especially polyps, myoma, adhesions, congenital abnormalities such as septate uterus. Technical aspects are shown. This procedure is painless, atraumatic and no adverse effect is seen if the usual precautions before hysterography are taken. The right place of this exam is between hysterography and hysteroscopy, but more widespread use is required before a final opinion can be reached.

Female↗
PubMed1994

Modulating effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on skin carcinogenesis initiated by the weak inducer 7,12-dimethylbenz(a)anthracene.

The effects of topical pretreatment of CF1-Swiss mice with TCDD on the carcinogenesis induced by DMBA were studied. We also determined the intrinsic features of DMBA as an aryl hydrocarbon hydroxylase (AHH) inducer through either its binding ability to Ah receptor or its inducing effects on benzo(a)pyrene (BP) hydroxylase or DMBA hydroxylase. DMBA is a poor ligand of the Ah receptor (26-fold and 4.3-fold weaker than 3-methylcholanthrene and BP respectively) and a very weak AHH inducer (ten million-fold weaker than TCDD). Nevertheless, DMBA induces a specific isozyme of cytochrome P-450 1A1 since, for an equal dose administered to C57BL/6 mice (200 mg/kg body weight), the DMBA-hydroxylase activity was 1.72-fold increased by DMBA while it remained unchanged after BP treatment. In contrast, the BP-hydroxylase activity was 1.91-fold increased by BP and only 1.47-fold by DMBA. A dose-dependent relationship exists between the increasing dose of TCDD (from 0.001 to 1 microg per mouse) applied to mouse skin and the induction of AHH activity of skin microsomes (from 1 to 60-fold increase). For carcinogenesis experiments, mice were either untreated or pretreated with single different doses of TCDD and, after 24h, DMBA (10 or 25 microg per mouse) was applied to the skin. The average number of papillomas per mouse was dependent on 1) the dose of DMBA and 2) the metabolic capacity of the skin. For 10 microg DMBA, the TCDD only exerts an anticarcinogenic effect (from 5.5 to 0.6 tumor per mouse) whereas for 25 microg DMBA, TCDD exerts a dual effect: first, a cocarcinogenic effect (from 6.2 to 9 and 11.5 tumors per mouse for 0.001 and 0.01 microg TCDD respectively) then an anticarcinogenic effect (2.3 and 1.5 tumors per mouse for 0.1 and 1 microg TCDD respectively). The discussion underlines the decisive importance of two factors: 1) the effective dose of the ultimate carcinogen in contact with cellular targets during a sensitive step of the cell cycle and 2) the time-persistence of a high steady state level of the carcinogen.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1991

Effects of ethanol and clofibrate on expression of cytochrome P-450 enzymes and epoxide hydrolase in cultures and cocultures of rat hepatocytes.

Cultured and cocultured rat hepatocytes were used to study the effects of ethanol and clofibrate on cytochrome P-450 (P-450) enzymes and epoxide hydrolase. We showed that in the presence of ethanol, clofibrate or both compounds, rat hepatocytes were able to express, after 3 days of pure culture, quantitatively and qualitatively reasonable levels of most cytochrome P-450 enzymes and epoxide hydrolase, compared to freshly isolated hepatocytes. However, ethanol induced the P-450IA subfamily, and clofibrate the P-450-IVA subfamily. In cocultures, after 6 days, most P-450 enzymes were still expressed while P-450IIC11 was completely lost. Ethanol and clofibrate had the same effect as in pure culture. These results show, by modifying culture medium conditions and cell-cell interactions, that it is possible to maintain reasonable xenobiotic-metabolizing-enzyme expression; however, these conditions have to be improved in order to preserve better P-450 expression. The mechanism of these effects and the inducibility of these systems remain to be elucidated by a study at molecular level.

Animals↗
PubMed1989

Glucocorticoid hormones prevent the induction of gamma-glutamyl transpeptidase by ethanol in a rat hepatoma cell line.

The increase in serum gamma-glutamyl transpeptidase (GGT) is a well known marker of chronic alcoholism in man. We have previously shown that ethanol (180 mM) induces GGT activity 2-3-fold in the C2 rat hepatoma cell line. In this study, we have analyzed the interaction of ethanol with steroid hormones and drugs in this well defined cell culture system. Dexamethasone (100 nM), a synthetic glucocorticoid agonist, completely prevented the induction of GGT by ethanol, but had no effect when added alone. This inhibitory effect was also observed with other corticosteroids, but not with sex steroids; it was prevented by RU 486, a glucocorticoid antagonist. These observations suggest that dexamethasone acts through a high affinity glucocorticoid receptor. Conversely, ethanol did not interfere with the glucocorticoid induction of alanine aminotransferase in the same cell. We have analyzed the metabolism of ethanol in the C2 cells. These cells lack significant alcohol dehydrogenase activity as well as any cytochrome P-450 Alc immunoreactivity. Dexamethasone did not modify the disappearance of ethanol in the culture medium of those cells. We conclude that glucocorticoid hormones interact with ethanol at the cellular level, and that this interaction does not involve a modification of alcohol metabolism.

Alanine Transaminase↗