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1.
Sci Total Environ ; 865: 161200, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36581265

RESUMEN

Streetlamp illumination disturbs the natural physiological processes and circadian rhythms of living organisms, including photosynthesizing "citizens". The light-emitting diode (LED) technology has replaced high-pressure sodium lamps. Therefore, the effects of LED streetlamps on urban trees need to be elucidated as these new lamps have a different light spectrum (with a peak in the blue and red regions of the spectrum, i.e., highly efficient wavebands for photosynthesis) compared to older technologies. To address the above-mentioned issue, two widely utilised tree species in the urban environment, including Platanus × acerifolia (P) and Tilia platyphyllos (T), were grown with or without the effect of LED streetlamps using two realistic illumination intensities (300 and 700 µmol m-2 s-1). Gas exchanges and biochemical features (starch, soluble sugar, and chlorophyll content) of illuminated vs non-illuminated trees were compared during the whole vegetative season. Our results showed that both tree species were strongly influenced by LED streetlamps at physiological and biochemical levels. Specifically, the mature leaves of P and T streetlamp-illuminated trees had a lower CO2 assimilation rate at dawn and had higher chlorophyll content, with lower starch content than controls. Our results showed that the differences between the effects of the two selected light intensities on the physiochemical attributes of P and T trees were not statistically significant, suggesting the absence of a dose-dependent effect. The most significant difference between T and P trees concerning the LED-triggered species-specific effect was that the delay in winter dormancy occurred only in P individuals. This study provided insights into the extent of LED streetlamp disturbance on trees. Our findings might raise awareness of the necessity to provide less impacting solutions to improve the wellness of trees in the urban environment.


Asunto(s)
Clorofila , Árboles , Humanos , Árboles/fisiología , Clorofila/análisis , Fotosíntesis/fisiología , Luz , Hojas de la Planta/química
2.
Tree Physiol ; 28(6): 873-83, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18381268

RESUMEN

We studied the interactive effects of water stress and solar irradiance on physiological and biochemical traits in Ligustrum vulgare L., with special emphasis on antioxidant enzymes and flavonoids. Water relations, photosynthetic performance, plant growth, activities of antioxidant enzymes and of phenylalanine-ammonia-lyase, and concentrations of nonstructural carbohydrates and phenylpropanoids were measured in plants growing in 12% (shade) or 100% (sun) sunlight and supplied with 100 or 40% of daily evapotranspiration-demand over a 4-week period. The mild water stress treatment caused leaf water potential and relative water content to decline on average by -0.22 MPa and 4.5%, respectively. In response to the water stress treatment, photosynthetic rates decreased more in sun plants than in shade plants, likely because of declines in photosystem II photochemistry, apparent maximum rate of carboxylation and apparent maximum electron transport rate coupled with significant reductions in stomatal conductance. Antioxidant enzymatic activities, which were much greater in sun leaves than in shade leaves under well-watered conditions, increased (particularly the enzymatic activities associated with hydrogen peroxide removal) in response to water stress only in shade leaves. Antioxidant phenylpropanoids, particularly quercetin and luteolin derivatives, markedly increased in response to full sunlight irrespective of water treatment; however, antioxidant phenylpropanoid concentrations increased in response to water stress only in shade leaves. We suggest that: (1) assimilated carbon in sun plants was used largely to support an effective antioxidant system capable of countering water-stress-induced oxidative damage--an example of cross tolerance; and (2) in shade plants, carbon was also diverted from growth to counter oxidative damage driven by the mild water-stress treatment. Both findings are consistent with the nearly exclusive distribution of L. vulgare in well-watered, partially shaded Mediterranean areas.


Asunto(s)
Ligustrum/fisiología , Luz Solar , Carbohidratos/fisiología , Clorofila/metabolismo , Flavonoides/metabolismo , Gases/metabolismo , Glucosa/metabolismo , Italia , Ligustrum/crecimiento & desarrollo , Ligustrum/efectos de la radiación , Fenoles/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Polifenoles , Abastecimiento de Agua
3.
Food Chem ; 110(2): 361-7, 2008 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-26049227

RESUMEN

The influence was evaluated of four rootstocks (Ishtara, Mr. S 2/5, GF 677 and Barrier 1) and of harvesting time (early, middle, late) on the quality characteristics and nutritional value (vitamin C, phenols, carotenoids, total antioxidant capacity) of 'Flavorcrest' peach. The better rootstocks were Mr. S 2/5 (low-vigour) and Barrier 1 (high-vigour). In particular, Flavorcrest fruit on Mr. S 2/5 and on Barrier 1 rootstocks had higher antioxidant capacities and also higher phytochemical content, although fruits on Mr. S 2/5 were less firm. Flesh firmness was best for fruits at mid-harvest (H2, 7 July 2006), whereas phytochemical contents were best at late harvest (H3, 13 July 2006), when, for all rootstocks, the best nutritional characteristics were also recorded. Total antioxidant capacity and phytochemical content were determined for the peel and flesh. The results show that removal of peel from peach results in a significant loss of total antioxidant capacity.

4.
Hum Reprod ; 22(6): 1578-84, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17337471

RESUMEN

BACKGROUND: Progestin-only methods are among the contraceptive options available for breastfeeding women, however the doses of progestin used in emergency contraception (EC) have not been evaluated in nursing mothers. We therefore investigated the pharmacokinetics of 1.5 mg levonorgestrel (LNG) in lactating women. METHODS: Twelve healthy exclusively breastfeeding volunteers received 1.5 mg LNG. Women refrained from nursing for 72 h after dosing and fed their infants with milk frozen beforehand. Serial blood and milk samples were collected for 120 h and assayed for LNG and sex hormone binding globulin. RESULTS: LNG concentrations peaked in plasma and in milk 1-4 h and 2-4 h after dosing, respectively. Concentrations in milk (M) paralleled those in plasma (P) but were consistently lower (mean M:P ratio 0.28). Estimated infant exposure to LNG is 1.6 microg on the day of dosing (1 microg in the first 8 h), 0.3 microg on the second day and 0.2 microg on the third day. CONCLUSIONS: Nursing mothers may need EC. These results suggest that to limit infant exposure to the period of maximum LNG excretion in milk, mothers should discontinue nursing for at least 8 h, but not more than 24 h, after EC.


Asunto(s)
Anticoncepción Postcoital , Anticonceptivos Poscoito/sangre , Anticonceptivos Poscoito/farmacocinética , Levonorgestrel/sangre , Levonorgestrel/farmacocinética , Leche Humana/química , Adolescente , Adulto , Lactancia Materna , Femenino , Humanos , Lactante , Recién Nacido , Lactancia , Globulina de Unión a Hormona Sexual/análisis
5.
Hum Reprod ; 20(10): 2764-8, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15980008

RESUMEN

BACKGROUND: Hormonal contraceptives have been associated with various effects on the bone mineral density (BMD) of pre-menopausal women. The aim of this study was to assess the effects of a vaginal contraceptive ring on BMD in pre-menopausal women and compare them with those of non-hormonal contraceptive use. METHODS: This open-label, multicentre study used dual-energy X-ray absorptiometry to measure BMD in the lumbar spine (L(2)-L(4)) and femoral neck regions. Subjects were assigned 3:1 to receive a contraceptive ring (n = 105) or a non-hormonal contraceptive control (n = 39) and were assessed after 13 and 26 cycles of contraceptive ring treatment or 12 and 24 months of control treatment. RESULTS: No change from baseline in BMD (Z-scores) was seen in contraceptive ring users (n = 73) at either time-point. In the control group (n = 30), BMD increased slightly from baseline resulting in significant differences (P < 0.0001) between the two groups at cycle 26/month 24. These differences are not clinically relevant, although some degree of acquisition of peak bone mass might have been prevented in the contraceptive ring group. The contraceptive ring was generally well tolerated; a higher incidence of treatment-related adverse events was observed in the contraceptive ring group compared with the non-hormonal contraceptive control group. CONCLUSIONS: In healthy pre-menopausal women, 2 years of contraceptive ring use produced no changes in BMD.


Asunto(s)
Densidad Ósea , Huesos/efectos de los fármacos , Anticonceptivos Femeninos/farmacología , Desogestrel/administración & dosificación , Desogestrel/farmacología , Etinilestradiol/administración & dosificación , Etinilestradiol/farmacología , Absorciometría de Fotón , Adolescente , Adulto , Densidad Ósea/efectos de los fármacos , Anticonceptivos Femeninos/efectos adversos , Estrógenos/administración & dosificación , Femenino , Cuello Femoral/efectos de los fármacos , Cuello Femoral/patología , Humanos , Vértebras Lumbares/efectos de los fármacos , Vértebras Lumbares/patología , Premenopausia , Factores de Tiempo
6.
Contraception ; 70(6): 442-50, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15541405

RESUMEN

We assessed to what extent the standard dose of levonorgestrel (LNG), used for emergency contraception, or a single dose (half dose), given in the follicular phase, affects the ovulatory process during the ensuing 5-day period. Fifty-eight women were divided into three groups according to timing of treatment. Each woman contributed with three treatment cycles separated by resting cycles. All received placebo in one cycle, and standard or single dose in two other cycles, in a randomized order. The diameter of the dominant follicle determined the time of treatment. Each woman had the same diameter assigned for all her treatments. Diameters were grouped into 33 categories: 12-14, 15-17 or 18-20 mm. Follicular rupture failed to occur during the 5-day period in 44%, 50% and 36% of cycles with the standard, half dose and placebo, respectively. Ovulatory dysfunction, characterized by follicular rupture associated with absent, blunted or mistimed gonadotropin surge, occurred in 35%, 36% and 5% of standard, single dose or placebo cycles, respectively. In conclusion, LNG can disrupt the ovulatory process in 93% of cycles treated when the diameter of the dominant follicle is between 12 and 17 mm. It is highly probable that this mode of action fully accounts for the contraceptive efficacy as well as the failure rate of this method. The present data suggest that half the dose may be as effective as the standard dose.


Asunto(s)
Anticonceptivos Sintéticos Orales/farmacología , Anticonceptivos Sintéticos Poscoito/farmacología , Levonorgestrel/farmacología , Folículo Ovárico/efectos de los fármacos , Ovulación/efectos de los fármacos , Adolescente , Adulto , Chile , Anticonceptivos Sintéticos Orales/administración & dosificación , Anticonceptivos Sintéticos Poscoito/administración & dosificación , República Dominicana , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Levonorgestrel/administración & dosificación , Hormona Luteinizante/sangre , Ciclo Menstrual/sangre , Ciclo Menstrual/efectos de los fármacos , Folículo Ovárico/diagnóstico por imagen , Ovulación/sangre , Ultrasonografía
7.
Contraception ; 65(2): 121-8, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11927114

RESUMEN

This study was conducted to assess to what extent the Yuzpe regimen, or half the dose, given in the follicular phase, prevents ovulation during the ensuing 5 days. Sixty women were divided into six groups. All groups received placebo in one cycle and drug in another, in a randomized order. Groups differed by the dose and size of the leading follicle at the time of treatment (12-14, 15-17, or 18-20 mm). Ovulation was absent during the ensuing 5 days in 13 of 20 participants (65%) and in 8 of 20 participants (40%) who received the full and the half dose, respectively, when follicles were 12-17 mm. No ovulation occurred, within the critical period, in 7 of 39 placebo cycles (18%). When follicles were 18-20 mm, treatment did not prevent ovulation. In most drug-treated cycles, plasma gonadotropin and sex steroid levels were significantly depressed within the 5-day period, even when follicular rupture occurred within that period. In conclusion, the Yuzpe regimen can suppress or postpone ovulation to an extent that exceeds the fertile life of spermatozoa. Lack of ovulation within the critical period and dysfunction of the ovulatory process probably account for the contraceptive effect of this method in most cases. The present data do not warrant the use of half the dose of the Yuzpe regimen.


Asunto(s)
Anticonceptivos Poscoito , Etinilestradiol/administración & dosificación , Fase Folicular , Levonorgestrel/administración & dosificación , Ovario/efectos de los fármacos , Ovario/fisiología , Anticonceptivos Poscoito/efectos adversos , Método Doble Ciego , Estradiol/sangre , Etinilestradiol/efectos adversos , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Levonorgestrel/efectos adversos , Hormona Luteinizante/sangre , Folículo Ovárico/anatomía & histología , Ovulación , Placebos
8.
Fertil Steril ; 75(4): 744-8, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11287029

RESUMEN

OBJECTIVE: To assess whether women who were administered the first injection of DMPA+E(2)C on day 7 of their menstrual cycle (delayed injection) exhibit the same degree of ovarian suppression as women who receive it on day 5 of their menstrual cycle. DESIGN: Multicenter, randomized controlled trial. SETTING: Reproductive health clinics. PATIENT(S): Women aged between 18 and 38 years (inclusive) willing to use DMPA+E(2)C as their method of contraception. INTERVENTION(S): Participants received a DMPA+E(2)C injection on day 5 (control group, n = 41) or day 7 (delayed-injection group, n = 117) of their menstrual cycle. MAIN OUTCOME MEASURE(S): Ovarian activity and follicular development determined by serial serum progesterone levels and vaginal ultrasound. RESULT(S): Participants who received DMPA+E(2)C on day 5 of their menstrual cycle (control group) exhibited no more than limited follicular growth (no follicle >16 mm). Of those women who received DMPA+E(2)C on day 7 of their menstrual cycle (delayed-injection group), 21 (18%) showed some follicular growth, of whom 4 (3%) ovulated. CONCLUSION(S): The first injection of DMPA+E(2)C given on day 7 of a menstrual cycle does not provide the same inhibition of ovarian activity as that observed when it is administered on day 5 of the menstrual cycle.


Asunto(s)
Anticonceptivos Femeninos/administración & dosificación , Estradiol/administración & dosificación , Acetato de Medroxiprogesterona/administración & dosificación , Ovario/fisiología , Adolescente , Adulto , Factores de Edad , Índice de Masa Corporal , Preparaciones de Acción Retardada , Estradiol/análogos & derivados , Femenino , Humanos , Ciclo Menstrual , Folículo Ovárico/diagnóstico por imagen , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología , Ovario/diagnóstico por imagen , Ovario/efectos de los fármacos , Ovulación/efectos de los fármacos , Progesterona/sangre , Ultrasonografía
9.
Hum Reprod ; 16(3): 463-8, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11228212

RESUMEN

Interaction of Neisseria gonorrhoeae with the oviductal epithelium in vitro was examined in 2 cm length segments obtained after surgical sterilization from users of copper T intrauterine device (IUD) or Norplant and control women. Segments perfused with N.gonorrhoeae suspensions were incubated from 30 min up to 4 h, fixed, frozen and cut in 6--10 microm sections. Bacteria were detected immunohistochemically with rabbit anti-gonococcal serum followed by light and confocal microscopy. Adhesion and internalization of gonococci by epithelial cells were observed at all incubation times, and both were higher in explants from users of copper T IUD or Norplant implants than controls. The epithelium of controls expressed CD66 and syndecan-1; but CD46 was found in only one out of six cases. The epithelium of copper T IUD users expressed CD66 but not syndecan-1 or CD46. Users of Norplant exhibited expression of CD46, CD66 and syndecan-1. Label was always found along the luminal border of the epithelium. There were more intraepithelial lymphocytes in users of contraceptive methods than in controls. Results indicate that (i) N.gonorrhoeae invade the oviductal epithelium from the first minutes of exposure, (ii) the epithelium is constitutively endowed with two known receptors for the gonococcus, CD66 and syndecan-1, (iii) copper T IUD and Norplant users exhibit higher rates of attachment and internalization of the gonococcus into the oviductal epithelium associated with changes in expression of gonococcal receptors.


Asunto(s)
Adhesión Bacteriana/efectos de los fármacos , Anticonceptivos Femeninos/farmacología , Cobre , Trompas Uterinas/metabolismo , Trompas Uterinas/microbiología , Dispositivos Intrauterinos , Levonorgestrel/farmacología , Neisseria gonorrhoeae/fisiología , Adulto , Animales , Antígenos CD/metabolismo , Antígenos de Diferenciación/metabolismo , Moléculas de Adhesión Celular , Epitelio/metabolismo , Epitelio/microbiología , Epitelio/patología , Trompas Uterinas/patología , Femenino , Gonorrea/metabolismo , Gonorrea/microbiología , Gonorrea/patología , Humanos , Linfocitos/patología , Proteína Cofactora de Membrana , Glicoproteínas de Membrana/metabolismo , Proteoglicanos/metabolismo , Conejos , Sindecano-1 , Sindecanos
10.
Contraception ; 64(6): 363-8, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11834235

RESUMEN

The objectives of this study were to assess whether women who were administered the first injection of the once-a-month contraceptive containing estradiol cypionate and 25 mg depot-medroxyprogesterone acetate (MPA+E(2)C) on Day 7 of their menstrual cycle (delayed injection) exhibit the same degree of cervical mucus changes as women who receive it on Day 5 of their menstrual cycle. This was a multicenter, randomized, controlled clinical trial. A total of 158 women, aged between 18 and 38 years (inclusive), who, were willing to use MPA+E(2)C as their contraceptive method participated in the trial. Participants received a MPA+E(2)C injection on Day 5 (control group, n = 41) or Day 7 (delayed-injection group, n = 117) of their menstrual cycle. Participants who received MPA+E(2)C on Day 5 of their menstrual cycle (control group) exhibited fair or poor mucus quality and poor sperm penetration. Of those women who received MPA+E(2)C on Day 7 of their menstrual cycle (delayed-injection group), 3 (3%) showed good mucus or good sperm penetration at some time point during follow-up. It is possible to conclude that the first injection of MPA+E(2)C given on Day 7 of a menstrual cycle does not provide the same degree of inhibition of mucus quality and sperm penetration as that observed if it is administered on Day 5. However, the theoretical risk of pregnancy after receiving MPA+E(2)C on Day 7 would be expected to be low.


Asunto(s)
Moco del Cuello Uterino/efectos de los fármacos , Anticonceptivos Femeninos/farmacología , Anticonceptivos Orales Combinados/farmacología , Estradiol/farmacología , Acetato de Medroxiprogesterona/farmacología , Adulto , Moco del Cuello Uterino/fisiología , Preparaciones de Acción Retardada/farmacología , Esquema de Medicación , Combinación de Medicamentos , Estradiol/análogos & derivados , Estradiol/sangre , Femenino , Humanos , Inyecciones Intramusculares , Ovario/efectos de los fármacos , Ovario/fisiología , Interacciones Espermatozoide-Óvulo/efectos de los fármacos , Factores de Tiempo
11.
Steroids ; 65(10-11): 703-7, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11108880

RESUMEN

Contraceptive methods for breastfeeding women should be safe for the mother and infant and should not interfere with lactation. Progestin-only methods meet these conditions and can be used from the sixth week postpartum. Because all progestins are excreted in milk, those that are insufficiently active by the oral route are preferable to avoid any possible effect on the baby. These steroids, however, must be administered to the mother by a non-oral route. Initially, progesterone was administered subdermally to test this concept. Subsequently, a progesterone vaginal ring was developed to be used continuously for 3 to 4 months and replaced with a new device, as needed, until weaning. Clinical trials have shown a high contraceptive efficacy (over 98.5%) and safety. The gross continuation rate of this method is approximately 40% at 12 months of use, with use-related problems being the main reason for discontinuation (26.8%). Currently, a Nestorone vaginal ring is under development, delivering 50 microg of Nestorone per day. It may be used continuously for up to one year, even if weaning occurs earlier. Both of these progestin-only rings prolong lactational amenorrhea to 10 to 12 months, which represents a health benefit and convenience for many women. The registration of the progesterone vaginal ring, developed as a contraceptive method to be used exclusively during lactation, has been approved in Chile and Perú. The fact that it is a user-controlled long-term contraceptive that delivers a natural hormone makes it an attractive option for many women.


Asunto(s)
Lactancia/efectos de los fármacos , Norprogesteronas/administración & dosificación , Administración Intravaginal , Adulto , Amenorrea/etiología , Lactancia Materna , Anticonceptivos Femeninos/administración & dosificación , Anticonceptivos Femeninos/efectos adversos , Anticonceptivos Femeninos/normas , Preparaciones de Acción Retardada , Evaluación de Medicamentos , Implantes de Medicamentos/efectos adversos , Implantes de Medicamentos/normas , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Ciclo Menstrual/efectos de los fármacos , Norprogesteronas/efectos adversos , Norprogesteronas/normas , Proyectos Piloto , Embarazo , Índice de Embarazo
12.
Contraception ; 61(3): 199-204, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10827334

RESUMEN

Nestorone(R) progestin (NES) is a potent 19-nor-progesterone derivative which is biologically inactive when administered orally; however, it is an excellent option for implant contraception. The objective of this study was to evaluate ovarian function during use of either one 4-cm or two 3-cm NES implants for 24 months. A total of 60 volunteers were enrolled in each dose group. Vaginal ultrasound (VUS) and blood sampling for determinations of estradiol (E(2)), progesterone (P) and NES serum levels were carried out twice a week for 6 consecutive weeks, beginning in months 1, 6, 12, 18, and 24 of implant use. Serum levels of NES declined with time, with a more pronounced decrease during the first 18 months of implant use; thereafter, NES levels remained stable until the end of the study at 24 months. Luteal activity was very infrequent during the first year of use (<3%) but increased during the second year, occurring in 27% and 35% of the sampling periods in the 1-implant group, and 2% and 16% of the sampling periods in the 2-implant group, at months 18 and 24 of use, respectively. No luteal activity was observed with NES levels above 80 pmol/L. Serum P levels in periods of luteal activity were significantly lower than those of controls. Persistent anovulatory follicles were the most common VUS finding and this was associated with E(2) levels that remained within the normal range (101-1500 pmol/L) in the majority of the sampling periods studied. Considering that a single implant offers advantage for insertion and removal, a new single NES implant is being developed with a slightly higher release rate, to reduce effectively the incidence of ovulation and provide a greater margin of safety beyond 2 years.


Asunto(s)
Anticonceptivos Femeninos/administración & dosificación , Norprogesteronas/administración & dosificación , Ovario/efectos de los fármacos , Ovario/fisiología , Adolescente , Adulto , Anticonceptivos Femeninos/sangre , Relación Dosis-Respuesta a Droga , Implantes de Medicamentos , Estradiol/sangre , Femenino , Humanos , Norprogesteronas/sangre , Folículo Ovárico/diagnóstico por imagen , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología , Ovario/diagnóstico por imagen , Ovulación/efectos de los fármacos , Progesterona/sangre , Ultrasonografía
13.
Hum Reprod ; 15(1): 118-22, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10611199

RESUMEN

An open, prospective, comparative study was done in healthy women, aged between 18 and 40 years, to study the effects of long-term etonogestrel treatment on bone mineral density (BMD). The control group used a non-hormone-medicated intrauterine device (IUD). The BMD was measured using a dual energy X-ray absorptiometry instrument. Measurements included the lumbar spine (L(2)-L(4)), the proximal femur (femoral neck, Ward's triangle, trochanter) and distal radius. The period of treatment was 2 years and 44 women in the Implanon group and 29 in the IUD group provided data. Groups were comparable at baseline with respect to age, weight, body mass index, BMD and 17beta-oestradiol status. Changes from baseline in BMD in the Implanon group were not essentially different from those in the IUD group. There was no relationship between 17beta-oestradiol concentrations and changes in BMD in this study population. The results of the present study indicate that Implanon((R)) can safely be used in young women who have not yet achieved their peak bone mass.


Asunto(s)
Densidad Ósea , Anticonceptivos Femeninos/administración & dosificación , Desogestrel , Congéneres de la Progesterona/administración & dosificación , Compuestos de Vinilo/administración & dosificación , Absorciometría de Fotón , Adolescente , Adulto , Peso Corporal , Anticonceptivos Femeninos/uso terapéutico , Implantes de Medicamentos , Estradiol/sangre , Femenino , Fémur , Humanos , Dispositivos Intrauterinos , Congéneres de la Progesterona/uso terapéutico , Estudios Prospectivos , Radio (Anatomía) , Compuestos de Vinilo/uso terapéutico
14.
Sex Transm Infect ; 76(6): 480-3, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11221133

RESUMEN

OBJECTIVE: We sought to determine the safety and acceptability of vaginal gel formulation PC-503 among low risk, abstinent women. The active ingredient was 2% pharmaceutical grade lambda carrageenan, a sulphated polymer that is generally recognised as safe by the US Food and Drug Administration. METHODS: 35 women in five sites applied 5 ml of the PC-503 gel vaginally once a day for 7 days while abstaining from sexual intercourse. Visual vaginal examinations were performed on days 1, 4, and 8. STI testing and vaginal pool Gram stain preparations were done on days 1 and 8. Participants were asked about product acceptability. RESULTS: 34 of the 35 women enrolled completed 7 days' use. Following product use, five reported mild symptoms including "bladder fullness," "genital warmth," or discomfort, and lower abdominal pain, and one had moderate pale yellow cervical discharge. Using the Nugent criteria, three women had bacterial vaginosis (BV) before and after use; three had BV before but not after, and two had BV after but not before. Most of the women found PC-503 to be pleasant or neutral in feel and smell and considered extra lubrication to be an advantage; however, one third found it to be messy. CONCLUSIONS: Vaginal use of PC-503 gel did not cause significant adverse effects in a small number of low risk, sexually abstinent women. Further testing in larger numbers of sexually active women is planned. A smaller volume of gel may be more acceptable to some women.


Asunto(s)
Antiinfecciosos Locales/administración & dosificación , Carragenina/administración & dosificación , Enfermedades de Transmisión Sexual/tratamiento farmacológico , Antiinfecciosos Locales/efectos adversos , Carragenina/efectos adversos , Femenino , Humanos , Satisfacción del Paciente , Cremas, Espumas y Geles Vaginales/administración & dosificación , Cremas, Espumas y Geles Vaginales/efectos adversos
15.
Contraception ; 60(1): 9-14, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10549447

RESUMEN

The contraceptive efficacy and safety of a progesterone-releasing vaginal ring (PVR) manufactured in Chile were compared to that of the Copper T 380A IUD (T-Cu) in nursing women enrolled at three Chilean clinics. A total of 285 volunteers chose to use the PVR and 262 the T-Cu. Plasma progesterone levels attained with the ring decreased from 25 to 14 nmol/L from month 1 to month 3 of use. Ring replacement was scheduled every 3 months. Volunteers continued in the study until weaning or completing the continuous use of four PVRs. No pregnancies occurred in 2320 and 2183 woman-months of exposure with the PVR and the T-Cu, respectively. Lower continuation rates in the first 6 months because of problems with use and a longer lactational amenorrhea were observed in the PVR than in the T-Cu group. Breast-feeding performance and infant growth were similar in both groups. These results confirm the high efficacy and safety of the PVR for nursing women and have led to the registration of the PVR by Chilean health authorities.


PIP: This study compares the contraceptive efficacy and safety of a progesterone-releasing vaginal ring (PVR) manufactured in Chile and a Copper T 380A IUD (T-Cu) in nursing women enrolled at three Chilean clinics. A total of 285 volunteers used the PVR and 262 used T-Cu. Plasma progesterone levels attained with the ring decreased from 25 to 14 nmol/l from month 1 to month 3 of use. Ring replacement was scheduled every 3 months. Volunteers continued in the study until weaning or completing the continuous use of 4 PVRs. There were no pregnancies in 2320 and 2183 woman-months of exposure with the PVR and the T-Cu, respectively. Lower continuation rates in the first 6 months because of problems with use and a longer lactational amenorrhea were seen in the PVR group. Breast-feeding performance and infant growth were similar in both groups. These results prove the high efficacy and safety of the PVR for nursing women. This has led to the registration of the PVR by Chilean health authorities.


Asunto(s)
Lactancia Materna , Dispositivos Anticonceptivos Femeninos/normas , Leche Humana/efectos de los fármacos , Progesterona/farmacocinética , Adulto , Amenorrea/inducido químicamente , Peso al Nacer , Peso Corporal , Chile , Colposcopía , Dispositivos Anticonceptivos Femeninos/efectos adversos , Femenino , Hemoglobinas/análisis , Humanos , Lactante , Dispositivos Intrauterinos de Cobre/efectos adversos , Dispositivos Intrauterinos de Cobre/normas , Lactancia , Masculino , Paridad , Pacientes Desistentes del Tratamiento , Satisfacción del Paciente , Progesterona/sangre , Progesterona/farmacología , Radioinmunoensayo , Vagina/efectos de los fármacos
16.
Hum Reprod ; 14(4): 976-81, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10221230

RESUMEN

An open, multicentre study was performed to assess efficacy, safety and acceptability of the single-rod contraceptive implant Implanon. The study involved 635 young healthy women, who were sexually active and of childbearing potential. The women were followed up every 3 months over the entire study period. Originally the study was designed for 2 years, but was extended to 3 years in a group of 147 women from two centres. Altogether, 21 centres in nine different countries participated. The average age of the women was 29 years (range 18-42 years), of whom 83.5% had been pregnant in the past. No pregnancy occurred during treatment with Implanon, resulting in a Pearl Index of 0 (95% confidence interval: 0.0-0.2). In the first 2 years, 31% had discontinued the treatment. Of the 147 women in the study extension, nine discontinued (6%) treatment. Bleeding irregularities was the main reason for discontinuation during the first 2 years of use (17.2%) and adverse experiences in the third year (3.4%). Implant insertion and removal were fast and uncomplicated in the vast majority (97%) of cases. Return of fertility was prompt. In conclusion, Implanon has excellent contraceptive action during its lifetime of 3 years. The safety profile is acceptable and not essentially different from progestogens in general.


Asunto(s)
Anticonceptivos Femeninos/administración & dosificación , Anticonceptivos Femeninos/efectos adversos , Desogestrel , Bombas de Infusión Implantables/efectos adversos , Compuestos de Vinilo/administración & dosificación , Compuestos de Vinilo/efectos adversos , Adolescente , Adulto , Femenino , Humanos , Embarazo , Resultado del Tratamiento , Hemorragia Uterina
17.
Hum Reprod ; 13(4): 793-8, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9619526

RESUMEN

Low-dose antiprogestin administration has been proposed as a new contraceptive modality to interference with endometrial receptivity without disturbing ovarian function. The effects of 1 mg/day mifepristone for 150 days on the menstrual cycle were assessed in 21 surgically sterilized women. The aim was to study each woman for one control cycle and during months 1, 3 and 5 of treatment. Ovulation, endometrial thickness, serum oestradiol and progesterone, urinary luteinizing hormone, endometrial morphology and cervical mucus were assessed. Luteal phase progesterone concentrations were observed in 36 of the 60 treated months assessed and less frequently as treatment progressed. The bleeding pattern was regular in most biphasic cycles, while prolonged interbleeding intervals or no bleeding were associated with monophasic cycles. Altered endometrial morphology was found in all cases irrespective of the occurrence of luteal activity. Increased endometrial thickness and dilated glands were observed in 25 and 34% respectively of the monophasic cycles. Mifepristone, 1 mg/day, interferes with endometrial development while allowing the occurrence of biphasic ovarian cycles and regular bleeding. However, it also prevents ovarian cyclicity in a high proportion of treated months, and this is associated with increased endometrial growth in some women, which may be of concern.


PIP: Low-dose antiprogestin administration has been proposed as a new contraceptive modality that interferes with endometrial receptivity without disturbing ovarian function. To explore this potential, the effects on the menstrual cycle of 1 mg/day of mifepristone for 150 days were assessed in 21 surgically sterilized women from Santiago, Chile. Control cycles were biphasic in all 21 women and ovulatory in 20 women. Luteal phase progesterone concentrations were observed in 36 of the 60 treatment months (1, 3, and 5) assessed. The proportion of ovulatory cycles was highest during month 1 and decreased progressively with treatment. 40% of treatment cycles were monophasic and bleeding cyclicity was altered in 57%. Prolonged inter-bleeding intervals or no bleeding occurred in monophasic cycles. Endometrial morphology was altered in all cases, regardless of the occurrence of luteal activity. Increased endometrial thickness and dilated glands were recorded in 25% and 34%, respectively, of the monophasic cycles. These findings suggest that 1 mg of mifepristone interferes with endometrial development while allowing biphasic ovarian cycles and regular bleeding. Whether these endometrial alterations are sufficient to prevent implantation remains to be established. The long-term effect of prevention of ovarian cyclicity and the associated increased endometrial growth recorded in some women require further investigation.


Asunto(s)
Anticonceptivos Sintéticos Orales/administración & dosificación , Mifepristona/administración & dosificación , Reproducción/efectos de los fármacos , Adulto , Moco del Cuello Uterino/efectos de los fármacos , Moco del Cuello Uterino/fisiología , Anticonceptivos Sintéticos Orales/efectos adversos , Anticonceptivos Sintéticos Orales/farmacología , Relación Dosis-Respuesta a Droga , Endometrio/efectos de los fármacos , Endometrio/crecimiento & desarrollo , Femenino , Humanos , Ciclo Menstrual/efectos de los fármacos , Ciclo Menstrual/fisiología , Mifepristona/efectos adversos , Mifepristona/farmacología , Ovario/efectos de los fármacos , Ovario/fisiología , Factores de Tiempo
18.
Hum Reprod ; 13(12): 3297-302, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9886502

RESUMEN

The effectiveness of a sequential regimen consisting of mifepristone, 10 mg/day for 15 days, followed by nomegestrol acetate (NOMA), 5 mg/day for the next 13 days, for inhibiting ovulation and maintaining regular bleeding cycles was assessed in 10 surgically sterilized volunteers who were followed for one pretreatment and three treated cycles. Hormonal determinations in blood and urine, ovarian ultrasonography, bleeding records in all cycles and an endometrial biopsy taken on day 22-25 of the third treatment cycle were used to monitor the effects of treatment. During treatment, 24 monophasic (no sustained progesterone rise above 12 nmol/l) and six biphasic cycles were recorded. Nine follicular ruptures were detected echographically in these 30 treated cycles, five of which occurred in monophasic cycles. All follicular ruptures occurred on days 1-7 of NOMA treatment. Echographic and endocrine features of ovulatory cycles were both present in only four treated cycles (13.3%). Development of a secretory endometrium was achieved in all cases, but it was always irregular. Regular withdrawal bleeding occurred in all subjects and no adverse reactions were recorded. The ovarian and endometrial effects of this regimen justify testing its contraceptive effectiveness in phase 2 clinical trials.


PIP: This study investigated the efficacy of mifepristone, 10 mg/day for 15 days, followed by nomegestrol acetate (NOMA), 5 mg/day for the next 13 days, for inhibiting ovulation and maintaining regular bleeding cycles in 10 surgically sterilized volunteers. To monitor the effects of treatment, hormonal determinations in blood and urine, ovarian ultrasonography, bleeding records in all cycles and endometrial biopsy were taken on day 22-25 of the third treatment cycle. About 24 monophasic and 6 biphasic cycles were recorded during treatment. About 9 follicular ruptures were echographically detected in these 30 cycles, 5 of which occurred in monophasic cycle. All follicular ruptures occurred in days 1-7 of NOMA treatment. Echographic and endocrine features of ovulatory cycles were both present in only four treated cycles (13.3%). Development of a secretory endometrium was achieved in all cases, but it was always irregular. Regular withdrawal bleeding occurred in all subjects and no adverse reactions were observed. The ovarian and endometrial effects of this regimen justify testing its contraceptive effectiveness in phase 2 clinical trials.


Asunto(s)
Anticonceptivos Orales Combinados/administración & dosificación , Megestrol , Inductores de la Menstruación/administración & dosificación , Mifepristona/administración & dosificación , Norpregnadienos/administración & dosificación , Ovulación/efectos de los fármacos , Adulto , Estradiol/sangre , Femenino , Humanos , Hormona Luteinizante/orina , Progesterona/sangre , Congéneres de la Progesterona/administración & dosificación , Esterilización Reproductiva
19.
Contraception ; 56(6): 387-9, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9494773

RESUMEN

There is an urgent need to develop safe, effective, and acceptable vaginal products for the prevention of sexually transmitted infections. Preliminary in vitro results suggest that vaginal formulations of sulfated polysaccharides, including iota-carrageenan, have the potential to block mucosal transmission of human immunodeficiency virus (HIV). Twenty-five women in five sites participated in Phase I trials to evaluate the safety of a formulation containing iota-carrageenan (PC 213). The results of this study indicate that a 5 mL 2% gel formulation of iota-carrageenan is not associated with significant irritation of the female reproductive tract when administered once daily in the absence of sexual intercourse. Given the small number of participants in this initial study, careful observation for potential irritation must also be included in larger studies of this and other vaginal formulations.


PIP: Preliminary in vitro results suggest that vaginal formulations of sulfated polysaccharides have the potential to block mucosal HIV transmission. Reported in this paper are the results of a 1995 Phase I trial of the safety of a formulation containing 2% iota-carrageenan (PC 213). Enrolled were 25 women at 5 sites (Australia, Chile, Dominican Republic, Finland, and US). Study participants self-administered 5 ml of PC 213 gel intravaginally for 7 days, during which time they abstained from sexual intercourse. 18 women had completely normal colposcopic examinations both at baseline and at 1 week of follow-up. 3 of the 4 women who had signs of minor cervical irritation at baseline had normal exams after product use. Colposcopy indicated new cervical or vaginal lesions after PC 213 use in 3 women, but only 1 such case (cervical erythema) could be attributed to product use. Participants considered the product easy to apply, not messy, and easily disposable. Both the safety and acceptability of this preparation should be re-examined in larger populations and under conditions of use during sexual intercourse.


Asunto(s)
Carragenina/administración & dosificación , Cuello del Útero/efectos de los fármacos , Excipientes/administración & dosificación , Vagina/efectos de los fármacos , Administración Intravaginal , Carragenina/efectos adversos , Carragenina/uso terapéutico , Colposcopía , Excipientes/efectos adversos , Excipientes/uso terapéutico , Femenino , Estudios de Seguimiento , Geles , Infecciones por VIH/prevención & control , Humanos , Enfermedades de Transmisión Sexual/prevención & control , Factores de Tiempo
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