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Biomedical subjects

A Dupont

Publications and source records attributed to A Dupont.

At least 91 records · Page 5Linked to original sources
PubMed1988

Sexuality changes in prostate cancer patients receiving antihormonal therapy combining the antiandrogen flutamide with medical (LHRH agonist) or surgical castration.

The results of a written questionnaire with 44 patients (pilot study) indicated that before the beginning of treatment for advanced prostatic cancer, most subjects had an active sexual life, as illustrated by a normal erotic imagery, an adequate sexual desire and a normal frequency of intercourse. More than three-quarters (80%) of subjects had at least one coitus a week. Slightly more than 50% were able to easily achieve an erection by erotic imagery or by a preferred sexual fantasy; 50% never experienced erectile problems. When compared with their previous sexual functioning, 70% of subjects noticed during the antiandrogenic treatment a major reduction in their interest for sexual intercourse which was maintained in only 18% of patients. It became impossible for 57% to induce an erection by erotic imagery. However, 19% claimed an ability to maintain an erection during sexual activity, as compared to 56% before treatment, but erections usually lacked full rigidity. Twenty-two percent of patients mentioned having nocturnal or morning erections. Despite this dramatic decrease in sexual activity in most patients, complete antiandrogen blockade left sexual activity in approximately 20% of patients. Due to the treatment's excellent tolerance, the findings suggest that such combined androgen blockade could be beneficial for the treatment of sex offenders.

Aged↗
PubMed1988

Combination therapy with flutamide and castration (LHRH agonist or orchiectomy) in previously untreated patients with clinical stage D2 prostate cancer: today's therapy of choice.

One hundred and ninety-nine patients with clinical stage D2 prostate cancer who had not received previous endocrine therapy or chemotherapy were treated with the combination therapy using the pure antiandrogen Flutamide and the LHRH agonist [D-Trp6]LHRH ethylamide for an average of 26 months (3-59 months). The objective response to the treatment was assessed according to the criteria of the U.S. NPCP. There was a 5.7-fold increase (26.3 vs 4.6%) in the percentage of patients who achieved a complete response compared with the results obtained in five recent studies limited to removal (orchiectomy) or blockade (DES or Leuprolide) of testicular androgens. Only 12 of the 186 evaluable patients (6.5%) did not show an objective positive response at the start of the combination therapy compared with an average of 18% in the same five studies using monotherapy. The duration of response was also significantly improved in the patients who received the combination therapy while the death rate was decreased by approximately two-fold during the first 4 yr of treatment. In fact, while an approximately 50% death rate is observed at 2 yr in all studies using monotherapy, the same 50% death rate is delayed by 2 yr in the present study. It should be mentioned that at the time of relapse under combination therapy, the treatment is continued and, in addition, further blockade of adrenal androgen secretion is achieved with aminoglutethimide. The marked (5.7-fold) improvement in the rate of complete objective responses coupled with the three-fold decrease in the number of non-responders, the increased duration of the positive responses and the two-fold decrease in the death rate during the first 4 yr of treatment are obtained with the combination therapy using Flutamide and castration, thus improving the quality and duration of life with no or minimal side-effects. By blocking the androgen receptors in the prostatic cancer tissue, the antiandrogen decreases the action of the androgens of adrenal origin and thus inhibits the growth of a large number of tumors which, otherwise, would continue to be stimulated by the adrenal androgens left after medical or surgical castration.

Aged↗
PubMed1988

Biochemical and immunochemical characterization of surface and excretory-secretory antigens of Loa loa microfilariae.

Detergent solubilized extracts of 125Iodogen surface-labelled Loa loa microfilariae revealed a relatively simple profile of two strongly labelled molecules of 23 and 67 kDa for blood microfilariae and several strongly labelled molecules of 23, 40, 42-67 kDa for in vitro born microfilariae. In addition, there were other weakly labelled molecules which were resolved after prolonged autoradiographic exposure. Surface molecules of 28, 29, and 33 kDa were unique to blood microfilariae, a 14.4 kDa molecule was unique to in vitro born microfilariae and molecules of 23, 40, and 75-84 kDa were common to both forms of microfilariae. The profile of excretory-secretory products consisted of molecules of 14.4-198 kDa. Human albumin was a predominant component of surface molecules and excretory-secretory products from blood microfilariae. Immunoprecipitation with occult and microfilaremic loaiasis sera demonstrated that the 23 kDa surface molecule and excretory-secretory products of 14.4 and 33 kDa were only recognized by occult loaiasis sera whereas surface molecules of 40 and 75-84 kDa and excretory-secretory products of 28 and 67 kDa were recognised by both sera. Studies with heterologous sera demonstrated that with the exception of the 75-84 kDa antigens, all the L. loa microfilarial surface antigens contained epitopes which were restricted to filarial parasites. Further studies revealed that the 23 kDa antigen was a protein which contained neither asparagine-N-linked oligosaccharides nor interchain disulfide-linkages.

Animals↗
PubMed1988

The identification and partial characterization of an immunodominant 29-31 kilodalton surface antigen expressed by adult worms of the human filaria Loa loa.

Detergent solubilized extracts of 125Iodogen surface labelled adult Loa loa revealed a relatively simple profile consisting of a strongly labelled molecule at 29-31 kDa and weakly labelled molecules at 14.5, 17, 21, 23, 34, 58, and 86 kDa. Residents of a L. loa endemic zone were assessed clinically and parasitologically and classified as microfilaremic, amicrofilaremic with documented ocular passage of adult worms, or 'resistant' subjects without any signs of infection. Sera from these subjects were used to identify L. loa adult surface antigens. All 'resistant' sera immunoprecipitated the 29-31 kDa antigen although some were more strongly reactive than others. The amicrofilaremic sera strongly immunoprecipitated the 29-31 kDa antigen, whereas microfilaremic sera reacted weakly or not at all with this antigen. Longer exposures of immunoprecipitates of strongly reactive sera revealed the recognition of additional antigens of 86, 44, 34, 23, 21, 17 and 14.5 kDa. Studies with heterologous sera demonstrated that these antigens contain cross-reactive epitopes which are restricted to filarial parasites. Biochemical characterization of the predominant 29-31 kDa antigen showed that it bound concanavalin A, was sensitive to proteases, and its antigenicity was resistant to heat but sensitive to periodate and endo-beta-N-acetylglucosaminidase H. These observations suggest that it is a glycoprotein containing mannose and N-acetylglucosamine residues and that the carbohydrate moiety is important for antibody binding. The importance of the 29-31 kDa glycoprotein in the immunobiology of loaiasis is suggested by the finding that resistant and infected amicrofilaremic individuals have strongly reactive IgG antibodies to this antigen.

Animals↗
PubMed1988

Important prognostic value of standardized objective criteria of response in stage D2 prostatic carcinoma.

One hundred and eighty-six previously untreated patients with clinical stage D2 prostate cancer have been followed according to the criteria of objective response of the National Prostatic Cancer Project (NPCP). All patients received combination therapy with the antiandrogen Flutamide and the LHRH agonist (D-Trp6, des-Gly-NH2(10)]LHRH ethylamide (or surgical castration, 10 patients) as first treatment. Forty-nine patients (26.3%) achieved a complete response as best response while 56 (30.1%) and 69 (37.1%) patients had partial and stable responses, respectively, and only 12 patients (6.5%) did not respond to treatment. The median times required to achieve stable, partial and complete responses were 155, 183 and 401 days, respectively. The best response achieved has a major influence on the probability of continuing response and survival. While the 50% probability of continuing response is more than 3 years for the complete responders, it is reduced to 630 and 517 days for partial and stable responders, respectively. While the non-responders have a median life expectancy of 10.0 months, this value is increased to 30.3 and 37.8 months for the stable and partial responders, respectively. The best probability of survival is for the complete responders with a 95.9% probability of survival at 3 years. There is no significant correlation between the time required to achieve a best response (phase 1) and the duration of the response before progression occurs (phase 2) or the time between progression and death (phase 3) for any of the categories of responses. A longer period of time required to achieve a complete response is associated with a longer survival. When analysis is made, in an attempt to predict response, of the baseline characteristics of the patients before treatment, a low number of bone metastases and better performance status are associated with a greater chance of achieving a complete response while partial, stable and progression responses cannot be predicted from the baseline characteristics. The present data show the importance of standardization of the objective criteria of response to treatment in advanced prostate cancer. Thus, the patients who achieve a complete response have a much more favorable prognosis while partial and stable categories of response have a closely similar prognosis which is inferior to the complete responders. Moreover, the present data indicate that the stable category of response has an important prognostic value which is almost superimposable and not statistically different from the partial response in terms of duration of response and survival.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1988

Combination therapy with flutamide and [D-Trp6]LHRH ethylamide for stage C prostatic carcinoma.

Sixty-seven previously untreated patients presenting with clinical stage C prostatic carcinoma with no evidence of distant metastases received combination therapy using the antiandrogen Flutamide and the LHRH agonist [D-Trp6]LHRH ethylamide for an average duration of treatment of 23.5 months. Only five patients have so far shown treatment failure with 91.8% of the patients still in remission at 2 years. Three patients have died from prostate cancer while three have died from other causes, 93.5% of the patients being alive at 2 years. Local control was achieved rapidly in all except one patient. Urinary obstruction and hydronephrosis were corrected in all cases. When comparing to recent data obtained after single endocrine therapy (orchiectomy or estrogens), or radiotherapy, the rate of treatment failure at 2 years is 3.5-fold lower after combination therapy (8.2%) than monotherapy (28.4%). The death rate at 2 years following start of the combination therapy is 6.5% while it is on average 22.2% (3.4-fold higher) in the studies using monotherapy (orchiectomy or estrogens) or radiotherapy. The present data suggest that treatment of prostate cancer with combination therapy before clinical evidence of dissemination of the disease permits a better response which is possibly explained, at least in part, by the lower degree of dedifferentiation and heterogeneity of the tumors.

Acid Phosphatase↗
PubMed1988

Benefits of combination therapy with flutamide in patients relapsing after castration.

Two hundred and nine patients with biopsy-proven stage D2 prostatic carcinoma showing disease progression after orchiectomy or treatment with DES (stilboestrol) or an LHRH agonist alone received combination therapy with the pure antiandrogen flutamide. In patients treated with DES, the oestrogen was replaced by the LHRH agonist [D-Trp6]LHRH ethylamide. The objective response to therapy was assessed according to the criteria of the US NPCP. Thirteen patients had a complete response to treatment, while partial and stable responses were achieved in 20 and 39 patients respectively (total objective response rate of 34.5%). The mean duration of response was 24 months. In the non-responders the median survival was 8.1 months with a 17% probability of survival at 2 years; the probabilities of survival at 2 years of the patients who showed partial and stable responses were 87 and 67% respectively. All patients who achieved a complete response are still alive. Combination therapy with Flutamide and castration (surgical or LHRH agonist) appears to be the treatment of choice for prostate cancer patients in relapse after standard endocrine therapy.

Aged↗
PubMed1988

Changes in plasma lipoproteins during various androgen suppression therapies in men with prostatic carcinoma: effects of orchiectomy, estrogen, and combination treatment with luteinizing hormone-releasing hormone agonist and flutamide.

Cardiovascular complications are a well recognized side-effect of antihormonal therapy in men with prostatic carcinoma. We studied changes in plasma lipoproteins in patients with prostate cancer during treatment with several androgen suppression therapies. Estrogen, orchiectomy, and a combination of LHRH agonist and antiandrogen (flutamide) reduced plasma testosterone concentrations (89-92%) and plasma estradiol decreased by 85%, 44%, and 54%, respectively. Estrogen induced hypertriglyceridemia and elevation of plasma HDL cholesterol, phospholipid, and apolipoprotein A-I and A-II concentrations. Low density lipoprotein (LDL) cholesterol decreased but LDL apolipoprotein B did not. These results suggest that the cardiovascular complications that occur during estrogen administration are not mediated through changes in lipoprotein profile, other than the hypertriglyceridemic effect. Orchiectomy caused hypercholesterolemia and an increase in both total and LDL apolipoprotein B, all of which are strong determinants of cardiovascular disease. The high density lipoprotein (HDL) concentration was not affected despite a reduction in plasma testosterone, perhaps due to a simultaneous decrease in estradiol. Combination therapy had no effect on plasma lipid and apolipoprotein B concentrations, but very low density lipoprotein (VLDL) apolipoprotein B decreased, and LDL apolipoprotein B increased. The HDL cholesterol and apolipoprotein A-I concentrations increased but A-II and phospholipids did not. These results suggest enhanced lipoprotein lipase activity, consistent with the reciprocal changes in VLDL and LDL apolipoprotein B levels, apolipoprotein B enrichment of LDL particles, and increase in HDL cholesterol. The higher apolipoprotein A-I to A-II ratio indicates an increase in HDL2 subfraction due to inhibition of endothelial hepatic lipase, increased secretion of apolipoprotein A-I, or both. These effects are attributed to estradiol, which decreased less than after orchiectomy, and to additional adrenal androgen inhibition by flutamide. We conclude that estradiol plays an important role in determining plasma lipoprotein concentrations in men, and androgens exert an antagonist effect. The lipoprotein profile resulting from the combination treatment is more beneficial than that resulting from orchiectomy or estrogen administration.

Aged↗
PubMed1988

Natural antibodies against three distinct and defined antigens of Plasmodium falciparum in residents of a mesoendemic area in Gabon.

The magnitude of the antibody response to three distinct and defined antigens of Plasmodium falciparum was assessed in 144 inhabitants of the Kassa district (Haut Ogooué Province, Gabon), a region where malaria is mesoendemic. Antibodies against a polypeptide consisting of 40 (Asn-Ala-Asn-Pro) repeats of P. falciparum circumsporozoite protein [(NANP)40] were detected by ELISA. Antibodies against the fusion peptide 31.1, which consists of the N-terminal portion of the 190-200 kDa glycoprotein, were also detected by ELISA. Antibodies against ring-infected erythrocyte surface antigens (RESA), mainly the P. falciparum 155 kDa antigen (Pf 155), were detected by IFA on glutaraldehyde-fixed P. falciparum infected red blood cells (IRBC). In addition, a standard IFA employing air-dried P. falciparum IRBC was used to detect antibodies against intraerythrocytic asexual forms. Parasitemia and spleen enlargement were also recorded. The frequency of sera positive for specific antibodies increased with age for all the antigens tested. Plateau antibody levels were reached at different ages for the different antigens. Individual antibody responses varied in titer to the different antigens. Subjects with parasite-negative thick smears showed higher titers of anti-31.1 as well as an increased frequency of anti-RESA antibodies compared to subjects having positive smears. No differences in the titer and in the prevalence of anti-(NANP)40 antibodies were found between these groups. The results suggest that the antibody response against asexual blood stage antigens, especially anti-RESA and anti-31.1, may play a role in controlling parasitemia.

Adolescent↗
PubMed1988

Endocrine effects of combined treatment with an LHRH agonist in association with flutamide in metastatic prostatic carcinoma.

The plasma levels of pituitary hormones (LH, FSH and prolactin) as well as testosterone were determined in 62 patients treated with combined therapy using the LHRH agonist [D-Trp6, des-Gly-NH2(10)]LHRH ethylamide and the antiandrogen Flutamide. Plasma radioimmunoassayable LH and FSH levels increased to 534% (p less than 0.01) and 150% (p less than 0.01) of control, respectively, during the first 5 days of treatment, while, afterwards, a marked inhibition was observed which remained constant at approximately 30-50% of control values during the whole period of treatment. All patients showed a decrease of plasma testosterone concentration to approximately 10% of control levels. Detailed determinations of plasma testicular and adrenal steroid levels were then performed in 15 patients. Our data indicate that, except for the blockade of testicular 17-hydroxyprogesterone secretion, the combined therapy has no effect on plasma C-21 steroid levels. However, adrenal C-19 steroids, namely dehydroepiandrosterone and its sulfate, androst-5-ene-3 beta, 17 beta-diol and androstenedione were decreased to approximately 50% of control values (p less than or equal to 0.01). The main testicular steroids, testosterone and dihydrotestosterone, which were increased during the first 10 days of combined administration, rapidly decreased and reached approximately 10% of control values at later time intervals. The present study extends our previous observations indicating that the combined antihormonal treatment affects both testicular and adrenal steroidogenesis. Moreover, we have demonstrated that, up to at least 2 years, this treatment, in addition to decreasing the serum levels of testicular androgens, causes an inhibition of the plasma levels of C-19 steroids from adrenal origin.

Adenocarcinoma↗
PubMed1988

[Seroprevalence of syphilis in urban and semi-rural populations of Gabon].

The seroprevalence of syphilis was studied in an urban and a semi-rural community in Gabon by a cluster sampling technique. The crude prevalence rate of treponemal infection in the semi-rural population was estimated to be 13.3 +/- 5.0% and in the urban population 19.4 +/- 4.6%. The age-adjusted prevalence rate was significantly higher in the urban than in the semi-rural population. In both areas, it was significantly higher in men than in women. No significant difference was observed according to age. These high rates indicate the need for a control program for sexually transmitted diseases.

Adolescent↗
PubMed1988

Combination therapy with flutamide and castration (orchiectomy or LHRH agonist): the minimal endocrine therapy in both untreated and previously treated patients with advanced prostate cancer.

One hundred fifty-four patients with clinical stage D2 prostate cancer with no previous endocrine therapy or chemotherapy received the combination therapy with the pure antiandrogen Flutamide and the LHRH agonist [D-Trp]LHRH ethylamide for an average of 22 months (3 to 49). The objective response to the treatment was assessed according to the criteria of the US NPCP. There was a 6.3-fold increase (29.2 versus 4.6%) in the percentage of patients who achieved a complete response as compared to the results achieved in 5 recent studies limited to removal (orchiectomy) or blockade (DES or Leuprolide) of testicular androgens. Only 4.5% of patients did not respond to the combination therapy as compared to an average of 18% by standard therapy. The duration of response is also significantly increased in the patients who received the combination therapy while the death rate was decreased by approximately 2-fold between 2 and 3 years of treatment. The marked (6.3-fold) improvement in the rate of complete objective responses coupled with the 4-fold decrease in the number of non responders, the increased duration of the positive responses and the 2-fold decrease in the death rate at 2 to 3 years of treatment are obtained with the combination therapy using Flutamide and castration with no or minimal secondary effects. In addition, two hundred nine patients with biopsy-proven stage D2 prostatic adenocarcinoma showing disease progression after orchiectomy, DES or an LHRH agonist used alone received the combination therapy with the pure antiandrogen Flutamide. In patients treated with DES, the estrogen was replaced by the LHRH agonist [D-Trp6]LHRH ethylamide. Objective response to therapy was also assessed according to the criteria of the US NPCP. Thirteen patients (6.2%) had a complete response to treatment while partial and stable responses were achieved in 20 (9.6%) and 39 (18.7%) patients, respectively, for a total objective response rate of 34.5%. The mean duration of response was 24 months. While, in the non responders, the median survival was 8.13 months with a 17% probability of survival at 2 years, the probability of survival of patients who showed partial and stable responses at 2 years was 87 and 67%, respectively. All patients who achieved a complete response are still alive. Considering the excellent tolerance coupled with an objective response observed in 34.5% of the patients, the combination therapy with Flutamide and castration (surgical or LHRH agonist) appears to be the treatment of choice for prostate cancer patients in relapse after standard endocrine therapy.

Adenocarcinoma↗
PubMed1987

Excretion of three major prostatic secretory proteins in the urine of normal men and patients with benign prostatic hypertrophy or prostate cancer.

We have studied the mode of excretion of three prostatic secretory proteins, namely acid phosphatase (PAP), prostate-specific antigen (PSA) and beta-inhibin, in the urine of normal adult men, and we have determined the urinary levels of these proteins in men with benign prostatic hypertrophy (BPH) or adenocarcinoma. The output of the three proteins was highly variable during the day. In order to minimize these variations, 24-hour urine samples were collected thereafter. Our study showed that PAP concentrations in 50% of men with or without symptomatic BPH were similar to those of normal young men. In the remaining 50%, PAP was undetectable. In contrast, average PSA and beta-inhibin concentrations were higher in patients with BPH than in young men (p less than 0.05). The three markers were decreased or nondetectable in about half of the patients with untreated prostatic cancer. This phenomenon was even more pronounced in patients receiving hormonal treatment (castration or diethylstilbestrol). However, some of these patients still excreted normal amounts of PAP, PSA, and beta-inhibin. Urinary and serum PAP levels showed no correlation. These results indicate that urinary prostatic markers provide an easy means to study the behavior of the primary prostatic tumor. This information may be of potential value since it is not obtained with serum markers which originate mostly from metastatic cells.

Acid Phosphatase↗