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Featured researches published by Juan Diaz.


Contraception | 1991

PROLONGED INTRAUTERINE CONTRACEPTION: A SEVEN-YEAR RANDOMIZED STUDY OF THE LEVONORGESTREL 20 mcg/DAY (LNg 20) AND THE COPPER T380 Ag IUDS

Irving Sivin; Janet Stern; Elsimar M. Coutinho; Carlos E.R. Mattos; Sayed El Mahgoub; Soledad Diaz; Margarita Pavez; Francisco Alvarez; Vivian Brache; Francisco Thevenin; Juan Diaz; Anibal Faundes; Margarita Díaz; Terence McCarthy; Daniel R. Mishell; Donna Shoupe

A levonorgestrel-releasing IUD and the Copper T 380Ag IUD were in randomized comparison for seven years in five clinics. In two other clinics the randomized study was truncated at five years, but use of the Copper T continued. No pregnancies occurred to users of either device in years 6 and 7. Cumulative pregnancy rates were 1.1 per 100 at seven years for the steroid-releasing and 1.4 per 100 for the copper-releasing IUDs. Cumulative rates of PID did not differ between devices. Infection rates appeared to be lowest during the sixth and seventh years of the study. Termination attributable to amenorrhea was the principal contributor to differences in cumulative continuation rates between devices. At the five clinics that carried the comparative study to seven years, cumulative continuation rates were 24.9 per 100 for LNg20 IUD users and 29.4 per 100 for TCu 380Ag users. Women who used either method for periods of five to seven years experienced, on average, marked to mild increases in hemoglobin as compared with levels at admission. The Copper T380 family and the LNg20 IUDs represent the most effective reversible contraceptive methods yet studied in long-term randomized trials.


Contraception | 2002

Bleeding patterns and clinical performance of the levonorgestrel-releasing intrauterine system (Mirena) up to two years.

Margarete Hidalgo; Luis Bahamondes; Marcos Perrotti; Juan Diaz; Cecilia Dantas-Monteiro; Carlos Alberto Petta

The objectives of this study were to evaluate the bleeding patterns and clinical performance during the first 2 years of use of an intrauterine system releasing 20 microg/day of levonorgestrel (LNG-IUS, Mirena). Two-hundred-fifty-six women accepted use of Mirena from April 1998 through September 1998. The gross cumulative discontinuation rate due to pregnancy and expulsion were significantly higher in women who used the device because of heavy bleeding. There was one pregnancy at the 15th month of use after an inadvertent expulsion of the device. The continuation rate was 66.2 at the end of the second year. Forty-four percent of women reported amenorrhea at the 6th month of use. This rate maintained stability at 50% after 12 and 24 months of use. Spotting was present in 25% of the users at 6 months, decreasing to 8% and 11% at 18 and 24 months, respectively. Oligomenorrhea was described by one-quarter of women and was similar at each observation period. Removals due to menstrual bleeding problems were concentrated in the first 6 months of use and mostly due to amenorrhea or menorrhagia. In conclusion, LNG-IUS showed a high contraceptive efficacy and a good continuation rate up to 2 years. In addition, a reduction of blood loss was observed a few months after insertion.


Contraception | 1990

Long-term contraception with the levonorgestrel 20 mcg/day (LNg 20) and the Copper T 380Ag intrauterine devices: A five-year randomized study

Irving Sivin; Sayed El Mahgoub; Terence McCarthy; Daniel R. Mishell; Donna Shoupe; Francisco Alvarez; Vivian Brache; Elvira Jimenez; Juan Diaz; Anibal Faundes; Margarita Díaz; Elsimar M. Coutinho; Carlos E.R. Mattos; Soledad Diaz; Margarita Pavez; Janet Stern

An intrauterine device, releasing approximately 20 micrograms/day of levonorgestrel (LNg 20), used by 1124 women, was studied in a randomized trial of five years duration in comparison with the Copper T, model TCu 380Agm in 1121 women. At five years, the gross cumulative pregnancy rate of 1.1 +/- 0.5 per 100 among users of the LNg 20 devices was not significantly different from the rate of 1.4 +/- 0.4 per 100 experienced by users of the Copper T 380Ag. The steroid-releasing IUD had significantly higher termination rates for expulsion and amenorrhea, a significantly lower termination rate for other menstrual problems and pain, and a lower continuation rate. The five-year continuation rate among women using the TCu 380Ag was 40.6 per 100 as compared with that of 33.0 per 100 among women randomized to the LNg 20 device (P less than .001). Terminations attributed to amenorrhea with the LNg device primarily account for differences in continuation. These two intrauterine devices are the most effective long-term, reversible IUDs yet reported in the literature. No other contraceptive methods have exhibited such low long-term pregnancy rates in randomized comparative trials.


Contraception | 2000

The effect upon the human vaginal histology of the long-term use of the injectable contraceptive Depo-Provera®☆

Luis Bahamondes; Miriam Aparecida da Silva Trevisan; Liliana Andrade; Nadia M. Marchi; Sara Castro; Juan Diaz; Anibal Faundes

The objective of the study was to evaluate the effect of long-term use of the injectable contraceptive depot medroxyprogesterone acetate (DMPA) on human vaginal histology. Twenty premenopausal women currently using DMPA as a contraceptive method for two and three years were compared with 20 regularly menstruating women, who never used Depo-Provera and/or other kind of hormonal contraceptive in the last 6 months prior to the study. Subjects and controls were matched by age (+/-1 year), body mass index (kg/m2) (+/-1.0), number of pregnancies (+/-1), age at first intercourse (+/-1 year), years of sexual activity (+/-1 year), and number of partners during their life (+/-1). Vaginal biopsies were performed in users at 90+/-7 days after the last injection and in nonusers at day 20-25 of the menstrual cycle. In addition, at the day of the biopsy a blood sample was collected to measure estradiol (in all women) and DMPA in users. The level of serum estradiol was significant lower in Depo-Provera users than in controls (p < 0.001). The thickness of the vaginal epithelium was not smaller among DMPA users than among controls, the mean count of Langerhans cells per mm of epithelium were almost identical in both groups, and no significant differences were found on the vaginal maturation indices. In conclusion, the use of Depo-Provera between two and three years did not affect vaginal thinning of the epithelium, Langerhans cell count or maturation index.


Contraception | 1984

Intrauterine contraception with copper and with levonorgestrel: A randomized study of the TCu 380Ag and levonorgestrel 20 mcg/day devices

Irving Sivin; Francisco Alvarez; Juan Diaz; Soledad Diaz; Sayed El Mahgoub; Elsimar M. Coutinho; Vivian Brache; Margarita Díaz; Anibal Faundes; Margarita Pavez; Carlos E.R. Mattos; Janet Stern

First year results of a randomized study of 1509 users of the Copper T380Ag with a silver core or of an IUD releasing 20 mcg day of levonorgestrel are reported. The cumulative gross pregnancy rate for each device was 0.3 per 100 at one year, with more than 490 women having one year of use with each device. The levonorgestrel-releasing device was associated with significantly fewer bleeding days and significantly increased hemoglobin levels when compared with pre-admission values or the one year values observed among users of the TCu380Ag. Terminations attributable to amenorrhea were significantly more frequent among users of the levonorgestrel-releasing device. The TCu 380Ag was associated with increased frequency and severity of dysmenorrhea compared with pre-admission levels or with the steroid-releasing device. Hemoglobin levels were somewhat reduced among users of the TCu 380Ag device. Terminations attributable to pain were, however, not significantly different by device. Continuation rates at the end of the first year were not significantly different by device.


American Journal of Public Health | 2010

Social-Environmental Factors and Protective Sexual Behavior Among Sex Workers: The Encontros Intervention in Brazil

Sheri A. Lippman; Angela Donini; Juan Diaz; Magda Chinaglia; Arthur Reingold; Deanna Kerrigan

OBJECTIVES We sought to determine the association of social-environmental factors with condom use and sexually transmitted infections (STIs) among 420 sex workers participating in an STI/HIV prevention study in Corumbá, Brazil, to inform future intervention efforts. METHODS Participants provided urine samples for polymerase chain reaction testing of chlamydia and gonorrhea and responded to multi-item scales addressing perceived social cohesion, participation in networks, and access to and management of resources. We conducted multivariate log-linear and negative binomial regression analyses of these data. RESULTS Increased social cohesion was inversely associated with number of unprotected sex acts in the preceding week among women (adjusted incidence rate ratio [IRR] = 0.80; P < .01), and there was a marginal association among men (adjusted IRR = 0.41; P = .08). Womens increased participation in social networks was associated with a decrease in frequency of unprotected sex acts (adjusted IRR = 0.83; P = .04), as was mens access to and management of social and material resources (IRR = 0.15; P = .01). Social-environmental factors were not associated with STIs. CONCLUSIONS The social context within which populations negotiate sexual behaviors is associated with condom use. Future efforts to prevent STI/HIV should incorporate strategies to modify the social environment.


Contraception | 1987

Two years of intrauterine contraception with levonorgestrel and with copper: A randomized comparison of the TCu 380Ag and levonorgestrel 20 mcg/day device

Irving Sivin; Janet Stern; Juan Diaz; Margarita Díaz; Anibal Faundes; Sayed El Mahgoub; Soledad Diaz; Margarita Pavez; Elsimar M. Coutinho; Carlos E.R. Mattos; Terry McCarthy; Daniel R. Mishell; Donna Shoupe; Francisco Alvarez; Vivian Brache; Elvira Jimenez

IUDs releasing 20 mcg/day of levonorgestrel (LNg20) were in randomized trial together with the Copper T, model TCu 380Ag, in seven centers involving 2244 women. Two-year (25 months) gross cumulative pregnancy rates were 0.2 +/- 0.2 and 0.9 +/- 0.3 for the levonorgestrel and copper releasing devices, respectively (P greater than 0.05). There were no ectopic pregnancies in more than 1600 woman-years of use of each device. Removal rates for bleeding and/or pain or for medical reasons other than menstrual problems did not differ significantly between devices. Oligomenorrhea or amenorrhea prompted 10.7 per hundred (gross rate, 8.4 net rate) women using the LNg 20 IUD to request removal in the two-year period, significantly above the 0.2 per hundred rate among women with the Copper IUD (P less than 0.001). At the end of two years an estimated 59.4 per 100 women were continuing use of the LNg 20 IUD, and 67.5 per 100 (P less than 0.001) with the TCu 380Ag. This difference is almost wholly ascribable to a marked reduction in bleeding episodes and days among women using the LNg 20 device with concomitant removal of device. Hemoglobin rose an average of 0.5 g/dl (P less than 0.001) for this group whereas women using the TCu 380Ag experienced a decline of 0.2 g/dl compared with baseline values (P less than 0.001).


Contraception | 2002

Therapeutic use of levonorgestrel-releasing intrauterine system in women with menorrhagia: a pilot study

Ilza Monteiro; Luis Bahamondes; Juan Diaz; Marcos Perrotti; Carlos Alberto Petta

The objective of this study was to evaluate the efficacy and performance, for up to 1 year, of an intrauterine system releasing 20 microg/day of levonorgestrel (LNG-IUS, Mirena) in the treatment of women with menorrhagia. It was a descriptive, prospective, non-comparative study. A 20 microg/day LNG-releasing-IUS was inserted on any day during bleeding to 44 women (between 24 and 49 years of age) who presented with menorrhagia after medical therapies had failed. Menstrual patterns were assessed, and hemoglobin concentrations were measured before LNG-IUS was inserted and at 3, 6, 9, and 12 months of use. The most common bleeding pattern at 3 months after insertion was spotting, and after 6, 9, and 12 months the majority of women presented with amenorrhea or oligomenorrhea. Three women requested removal of the LNG-IUS because of spotting, and six women expelled it spontaneously. Hemoglobin levels were improved from 102 g/L to 123 and 128 g/L at 3 and 12 months, respectively, after insertion of the LNG-IUS (p < 0.01). At 12 months 79.5% of participants continued the use of LNG-IUS. In conclusion, LNG-IUS was an effective treatment for three out of four women with menorrhagia and could be an alternative treatment for women with menorrhagia who are either contraindicated for or refuse hysterectomy or endometrial ablation.


Contraception | 1981

A multicenter study of levonorgestrel-estradiol contraceptive vaginal rings. I-Use effectiveness. An international comparative trial.

Irving Sivin; Daniel R. Mishell; Arne Victor; Soledad Diaz; Francisco Alvarez-Sanchez; Niels Christian Nielsen; Oladele Akinla; Tapani Pyorala; Elsimar M. Coutinho; Anibal Faundes; Subir Roy; Paul F. Brenner; Tom Ahren; Margarita Pavez; Vivian Brache; O.F. Giwa-Osagie; Margaret O. Fasan; Belinha Zausner-Guelman; Elias Darze; Jose Carlos Gama daSilva; Juan Diaz; Theodore M. Jackanicz; Janet Stern; Harold A. Nash

Contraceptive vaginal rings (CVRs), with approximate daily release rates of 250-290 mcg of levonorgestrel and 150-180 mcg of estradiol and manufactured in a shell design, were studied for effectiveness and acceptability in multicentered trials involving 1103 ring users in Brazil, Chile, Dominican Republic, Sweden, U.S., Denmark/Finland, and Nigeria. A comparison group of 533 women used the oral contraceptive Nordette. Both 1st and all segment 1 year gross pregnancy rates among CVR users were less than 3/100, rates similar to Nordette users. Continuation at 1 year was 50/100 users of the ring (all segments) and 38/100 among Nordette users, more of whom were lost to follow-up. Gross 1 year rates of termination for medical reasons ranged from 25-29/100. Ring users were more likely to terminate for vaginal problems and pill users for headache, nausea, and associated reasons. These trials indicate that CVRs of this design are as effective and have continuation rates equal to and possibly superior to Nordette under the same study conditions.


Aids Care-psychological and Socio-medical Aspects of Aids\/hiv | 2008

HIV-related stigma, service utilization, and status disclosure among truck drivers crossing the Southern borders in Brazil

Julie Pulerwitz; A. P. Michaelis; Sheri A. Lippman; Magda Chinaglia; Juan Diaz

Abstract HIV-related stigma and discrimination (S&D) have been shown to impede prevention, care and treatment. Yet, few quantitative studies have tested the associations between stigma, service utilization and status disclosure, especially in countries with concentrated HIV epidemics. Surveys, administered to a random sample of 1,775 truck drivers crossing Southern borders in Brazil, included items on multiple conceptual domains of S&D, such as fear of casual contact and blame towards people living with HIV/AIDS. Pearsons chi-square tests and logistic regression were used to examine correlations. Less stigma (both individual items and grouped as a scale) was significantly correlated with VCT use (p≤0.001), knowing where to get tested (p≤0.001) and willingness to disclose HIV-positive test results (p=0.013). Findings indicate that stigma is an important barrier to HIV testing and disclosure among truck drivers in Southern Brazil. Learning more about stigma is important given the growing assertions that testing is a ‘critical gateway’ to HIV prevention and treatment. As access to HIV testing and treatment improves, providers increasingly need to understand and address how stigma acts as a barrier to services.

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Anibal Faundes

State University of Campinas

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Margarita Díaz

State University of Campinas

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Luis Bahamondes

State University of Campinas

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Carlos Alberto Petta

State University of Campinas

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Nadia M. Marchi

State University of Campinas

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