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P Dionne

Publications and source records attributed to P Dionne.

At least 19 recordsLinked to original sources
PubMed2002

[Fertility after ectopic pregnancy at the University Hospital in Dakar].

The aims is to evaluate fertility and medical cost about post ectopic pregnancy follow up. It is about a retrospective and descriptive study about 337 patients who have the opportunity to get a salpingectomy for an ectopic pregnancy between 1989 and 1997 at Le Dantec Gynecological and Obstetrical Clinic. After the ectopic pregnancy cure, women are followed with contraception, just time before trying to obtain another pregnancy. The studied parameters are: age, parity, socio-economical status, level of instruction, obstetrical and gynecological antecedents, Chlamydia serology, hysterosaipingography data, fertility after ectopic pregnancy, fees related to the cost of follow up after ectopic pregnancy. Data exploitation is done through an epidemiologic programme named Epi Info version 5 The average age of the patients was 27 years and that of the parity was 2.70. 87.83% of women were married. More than the half of those patients came from the suburb of Dakar. 171 patients (50.74%) were followed regularly, the other 166 (49.26%) disappeared. A Chlamydia trachomatis infection was found among 23.4% of cases. A tubal obstruction was noted in the level of the horns at 12.5 % of women. No case of maternal death was observed. Among 59 patients who wished a pregnancy, 34 ectopic pregnancy had been obtained (57.62%) in 4 month after stopping contraception and 26 cases of a new ectopic pregnancy. The expenses of medical cure after ectopic pregnancy are about 17.814 to 71,574.65 F CFA with an average of 38,689 F CFA (389.89 FF). Medical care after ectopic pregnancy raises a lot of problems: --some patients disappeared probably because of the inaccessibility of financial cost, --the high rate of Chlamydial trachomatis infection, an hypofertility after ectopic pregnancy. To combat this, we have to insist in the prevention of sexually transmitted diseases in general and of the chlamydial infection in particular. We have also to insist in the early diagnosis of the ectopic pregnancy. At last, we must set up a registre of ectopic pregnancy at the national level.

Adolescent↗
PubMed1998

A 6beta-(thiaheptanamide) derivative of estradiol as inhibitor of 17beta-hydroxysteroid dehydrogenase type 1.

In an effort to develop potent agents for reducing the levels of the active estrogen, estradiol, we developed a new category of 17beta-hydroxysteroid dehydrogenase (17beta-HSD) type 1 inhibitors. The compounds described possess a butyl methyl alkylamide side chain linked to the C6 position of estradiol by a thioether. With a series of epimeric mixtures, an optimal side-chain length of five methylene groups (between the amide group and steroid part) was first determined. Thereafter, both C6 epimers of optimized mixture were obtained after high-pressure liquid chromatography separation. 1H and 13C NMR experiments were performed to confirm the stereochemistry of each epimer. The 6beta-orientation of the side-chain was found to be crucial for enzymatic inhibition. Indeed, for the optimized side-chain length, the compound with a beta-orientation (5: N-butyl,N-methyl 7-(3',17'beta-dihydroxy-1',3',5'( 10')-estratriene-6'beta-yl)-7-thiaheptanamide) was 70-fold more potent than the 6alpha-analog. Compound 5 did not inactivate 17beta-HSD type 1, suggesting a reversible inhibitor. In addition, it was found to be a more potent inhibitor than the substrate estrone itself or a panel of three known inhibitors.

17-Hydroxysteroid Dehydrogenases↗
PubMed1998

[Vaginal injuries during coitus].

Based on a prospective study on a continuous series of women admitted on emergency for post-coitus hemorrhage. The authors present an epidemiology and prognosis of vaginal injuries in to coitus in the Dakar University Teaching Hospital. Over a period of 33 months (October 1991 to December 1994), 106 cases were recorded, giving an incidence rate of 32 cases per year. The average profile is that of young women (26 years), usually during the post-partum period (41.5%) or in the second phase of menstrual cycle (32%). The main influencing factors found included: chronic vaginal infection (74%), position during coitus (especially that dorsal decubitus with hyperflexion and abduction of the lower members (56%), sexual abstinence of 3 months on average (21 days to 2 years), and use of aggressive product "aphrodisiac" for vaginal mucus. The damage was most often located at the bottom of dead end of Douglas and could be estimated at 5 cm long and 5 mm deep. The immediate prognosis was favourable, after stitching with absorbable thread, healing was obtained within 8 to 15 days. Given a retrospective view about 2 to 5 years, morbidity was represented by 3 recurrent cases and 13% after effects of the deep dyspareunia type.

Adolescent↗
PubMed1997

D-ring allyl derivatives of 17 beta- and 17 alpha-estradiols: chemical synthesis and 13C NMR data.

We report the 13C NMR data for 17 beta-estradiol, 17 alpha-estradiol, and a series of ten 17 beta- or 17 alpha-estradiol derivatives bearing an allyl group on the D-ring (at C-17, C-16, and C-15 positions). The target 17 beta-OH estradiol derivatives were synthesized from estrone by well known methods to ensure the accuracy of the allyl stereochemistry. The 17 alpha-estradiol derivatives were obtained by a modified Mitsunobu alcohol inversion of 17 beta-analogs. The carbon assignments were done using 1D and 2D NMR experiments. Six positions of the allyl group (17 alpha, 17 beta, 16 alpha, 16 beta, 15 alpha, and 15 beta) and two alcohol stereochemistries (17 beta and 17 alpha) of the D-ring were studied, resulting in an important source of data. The effect of allyl-positioning and alcohol stereochemistry on 13C NMR chemical shifts was also identified, producing important points of comparison for other steroid analogs.

Estradiol↗
PubMed1997

[Sexually transmitted diseases and female sterility at the University Hospital Center of Dakar: management and prevention].

It is a retrospective study supporting 82 cases continued series of feminine sterility and which objective is to evaluate the nursing management quality of genital infection in exploration and treatment of sterility. Women mean age is 26 years old, sterility is most primary frequently (68%) and from fallopian origin (80%). Followers examinations have been asked: vaginal taking (100%), urines cytobacteriology examination (56%), syphilis serology (23%), chlamydia serology (57%), mycoplasma serology (03%). Genital infection have been diagnosed in 75% of cases, in 33% of cases positive Chlamydia serology was found. Three molecules have been used principally in treatment: cyclines 50%, imidazoles derived 47%, lactamines 15%. The upper cost of diagnostic and treatments produce a wishest of prevention which based is the tracking and the precocious treatment of STD.

Adolescent↗
PubMed1997

[Antibiotic prophylaxis à la carte in self-contaminated gynecologic and obstetric surgery: importance of cefotaxime].

Infections represents 5% of our post-operative morbidity and result in the use of expensive antibiotics and longer hospital stays. As a less expensive alternative to systematic antibiotherapy for all patients, the authors propose a prospective and descriptive study of the effectiveness of antibioprophylaxis by administering 1 g of Cefotaxime pre-operatively. The study concerns a continuous series of 103 cases in gynaecology and obstetrics operated in the Dakar University Teaching Hospital, during a 13 months period (April 95-April 96). The average age of the patients is 30 years, the major types of surgery was cesarean sections, laparotomy for extra-uterine pregnancy and myomectomies. The duration of the surgery varied between 40 to 105 minutes with an average of 60 minutes. There was no intolerance to Cefotaxime. No cases of post operative infections were observed. All surgical wounds healed in 6 to 8 days except 2 minor cases of non-union of 1 cm. Antibioprophylaxis with Cefotaxime can therefore be considered as an effective means of preventing post-operative infections in clean surgery. It is easy to administer and also has the advantage of lower cost (4050 Fcfa compared to 29,000 Fcfa for classic antibiotherapy).

Adolescent↗
PubMed1996

2,2'-Dithiobis(N-ethyl-spermine-5-carboxamide) is a high affinity, membrane-impermeant antagonist of the mammalian polyamine transport system.

We have synthesized 2,2'-dithiobis(N-ethyl-spermine-5-carboxamide) (DESC), its thiol monomer (MESC), and the mixed MESC-cysteamine disulfide (DEASC) as potential inhibitors of polyamine transport in mammalian cells. DESC was the most potent antagonist of spermine transport in ZR-75-1 human breast cancer cells, with Ki values of 5. 0 +/- 0.7, 80 +/- 31, and 16 +/- 3 microM for DESC, MESC, and DEASC, respectively. DESC also strongly blocked putrescine and spermidine uptake in ZR-75-1 cells (Ki = 1.6 +/- 0.5 and 2.7 +/- 1.1 microM, respectively). While DESC and MESC were purely competitive inhibitors of putrescine transport, DEASC was a mixed competitive/noncompetitive antagonist. Remarkably, DESC was virtually impermeant in ZR-75-1 cells despite its low Ki toward polyamine transport. The marked difference in affinity between DESC and MESC was essentially due to the tail-to-tail juxtaposition of two spermine-like structures, suggesting that dimeric ligands of the polyamine transporter might simultaneously interact with more than one binding site. While DESC strongly decreased the initial rate of [3H]spermidine transport, even a 40-fold molar excess of antagonist could not completely abolish intracellular spermidine accumulation. Moreover, as little as 0.3 microM spermidine fully restored growth in ZR-75-1 cells treated with an inhibitor of polyamine biosynthesis in the presence of 50 microM DESC, thus emphasizing the importance of uptake of trace amounts of exogenous polyamines. Thus, reducing the exogenous supply of polyamines with a potent competitive inhibitor may be kinetically inadequate to block replenishment of the polyamine pool in polyamine-depleted tumor cells that display high transport capacity. These results demonstrate that polyamine analogues cross-linked into a dimeric structure such as DESC interact with high affinity with the mammalian polyamine carrier without being used as substrates. These novel properties provide a framework for the design of specific irreversible inhibitors of the polyamine transporter, which should present advantages over competitive antagonists for an efficient blockade of polyamine transport in tumor cells.

Animals↗
PubMed1995

13C nuclear magnetic resonance study of 17 alpha-substituted estradiols.

We report the 13C NMR data for 20 compounds bearing a substituent (alkyl, alkenyl, alkynyl, alkylamide, spiro-gamma-lactone, phenyl, benzyl, naphthyl, etc.) at the 17 alpha-position of estradiol. The carbon assignments were done using 1D and 2D NMR experiments (distortionless enhancement by polarization transfer, homonuclear correlated spectroscopy, heteronuclear shift correlation, and heteronuclear shift correlation via long-range couplings). Only the chemical shifts of carbons 12-18, which surround the substitution site, were affected by the addition of a substituent. The magnitude of the effects (shielding or deshielding) was influenced by the 17 alpha-substituent. The individual effects at these carbons were sufficiently distinctive to identify specific centers and should be valuable for signal assignment of a variety of 17 alpha-derivatives of estradiol. In addition to carbon-skeleton assignment, we also report the carbon-substituent assignments.

Estradiol↗
PubMed1995

[Epidemiological and anatomo-clinical features of extra-uterine pregnancies at the Dakar University Hospital Center].

It is the prospective study of 226 cases of operated ectopic pregnancies, in order to draw the epidemiological outline of such an affliction adn find out the possible etiologies. During this study, 107 swabs were anatomically exploited. An analysis of the results reveals the high frequency of disrupted ectopic pregnancies (over 90%). The ampullary localization exists in 73.45% of the cases. In the histological level, in 82.70 of the cases, the tubal pregnancy has been associated with a salpingitis or malformed lesions. The death rate is about 2.65%. In other respects, it appears that the limits of echography are actual, hence the importance of basic clinic, that mutilating surgery remains prevalent; histology also plays an unavoidable part in the diagnosis.

Adolescent↗
PubMed1994

1H and 13C nuclear magnetic resonance assignments and stereochemistry of N-n-butyl-N-methyl-11-(16'alpha-chloro-3',17'beta- and 17'alpha-dihydroxyestra-1',3',5'(10')-trien-7'alpha-yl) undecanamide.

The stereochemistry of N-n-butyl-N-methyl-11-(16'alpha-chloro-3',17'beta-dihydroxyestra-1 ',3',5'(10')- trien-7'alpha-yl) undecanamide (4) and N-n-butyl-N-methyl-11-(16'alpha-chloro-3',17'alpha-dihydroxyestra- 1',3',5'(10') - trien-7'alpha-yl) undecanamide (5) at the 17'-position was unambiguously established by one dimensional nuclear Overhauser enhancement (NOE difference spectroscopy). Irradiation of H-18' led to the increase in the signal of H-11'beta, H-12'beta, H-8'beta, H-15'beta, and H-16'beta for compound 4 and a very small increase in the signal of H-17' indicating the beta-orientation of the 17'-OH. In contrast, for compound 5, the increase in the signal of H-17' indicated the alpha-orientation of the 17'-hydroxy group. Complete assignment of the 1H and 13C resonances is facilitated by the following one- and two-dimensional NMR experiments: 1H homonuclear correlated spectroscopy (COSY), 1H-13C heteronuclear shift correlation (HSC), 1H-13C heteronuclear shift correlation via long range couplings (COLOC), and distortionless enhancement by polarisation transfer (DEPT). Comparison of the 1H and 13C NMR chemical shifts indicates that the stereochemistry at the 17' position is more easy to determine by analysing the chemical shifts of C-17', C-12', and C-18'.

Cadmium↗
PubMed1990

Protein synthesis and acrosome reaction-inducing activity of human cumulus cells.

The acrosome reaction of human spermatozoa is a prerequisite to fertilization. It has been hypothesized that secretions of cumulus cells could be involved in the induction of this sperm reaction. A source of variation in the in-vitro fertilization of human oocytes could be the maturational differences in the cumulus cells which affect the acrosome reaction. In order to investigate this possibility, we have studied the capability of secretions obtained from cumulus cells of different maturational stages to induce the acrosome reaction. Capacitated spermatozoa were exposed to the culture medium containing cumulus cell secretions and their acrosomal status was evaluated using the triple stain technique. The maturational status of the cumulus or fertilization of the enclosed oocyte did not influence the percentage of acrosome-reacted live spermatozoa. In order to further document these observations, cumulus cells were submitted to [35S]methionine incorporation and total and secreted proteins were analysed by SDS-PAGE electrophoresis. Neither quantitative nor qualitative changes were detected in the electrophoretic patterns of the proteins obtained from cumulus cells of different maturational status. Thus, variation of the acrosome reaction-inducing activity of cumulus cells does not appear to be involved in the variable fertilization of oocytes obtained from follicles of differing maturity.

Acrosome↗
PubMed1989

Qualitative changes in protein synthesis associated with polyspermic fertilization of human eggs.

To investigate the early molecular events in human oocytes that are triggered by fertilization, the authors examined the pattern of polypeptides synthesized by unfertilized and dispermic embryos obtained through an in vitro fertilization and embryo transfer (IVF-ET) program. Compared with unfertilized oocytes of the same postovulatory age, the de novo protein synthesis in tripronuclear dispermic zygotes (21 hours postinsemination) was characterized by the appearance of three novel protein bands with molecular weights of 41.2, 35.3, and 26.0 kD. Concomitant with these changes, these zygotes showed the disappearance of bands at 54.0, 36.5, and 28.0 kD, along with the decreased synthesis of a protein band at 42.5 kD. Although 24% of the aged unfertilized oocytes exhibited bands corresponding to 41.2 and 35.3 kD, the 26.0 kD protein is restricted to the tripronuclear embryos. The significance of these results is discussed in relation to the use of polyspermic human oocytes as a model for the study of the early molecular events triggered by fertilization.

Densitometry↗
PubMed1975

Effect of tetracycline on puromycin-induced polysome degradation: influence of magnesium and polyamines.

Puromycin-induced polysome degradation has been shown to require G factor, guanosine 5'-triphosphate, and the presence of a ribosome release factor (Hirashima and Kaji, 1972, 1973). Tetracycline, which does not inhibit formation of peptidyl-puromycin (Gottesman, 1967; Sarkar and Thach, 1968) nor the guanosine 5'-triphosphate hydrolysis mediated by elongation factor Tu (Ono et al., 1969), inhibits polysome degradation. The tetracycline inhibition requires Mg(2+) at concentrations above 8 mM, which are inhibitory to protein synthesis in vitro. At concentrations of Mg(2+) below 8 mM, polysome degradation is insensitive to tetracycline, but not to fusidic acid. Addition of spermidine, but not of other polyamines, enables the tetracycline inhibition to occur at concentrations of Mg(2+) as low as 2 mM. The inhibition by tetracycline and by fusidic acid suggests that ribosome movement may be essential for the function of ribosome release factor, or that these antibiotics may directly affect its action.

Escherichia coli↗