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2.
Maturitas ; 41 Suppl 1: S65-83, 2002 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11955796

RESUMO

Recent discoveries on endocrine, paracrine and autocrine involvement of insulin-like growth factor-1 (IGF-1) in the proliferation of many tissues raised the attention of its role in reproduction and in the growth of various cancers as well as of benign proliferations. The intention of this article is to focus on IGF-1 in the field of gynaecology. Perimenopausal women who exhibit high IGF-1 and low IGF binding protein (IGFBP) levels, like IGFBG-3, have an increased risk of developing breast cancer. A higher risk for cervical, ovarian and endometrial cancer is related to high IGF-1 levels in post- and premenopausal women. It has been shown that myomas, by far the most common benign uterine tumor in women, grow in the presence of IGF-1, in vitro as well as in vivo. Studies show that IGF-1 is involved in the differentiation of various reproductive tissues, like endometrium and ovarian tissues. Patients suffering from polycystic ovary syndrome (PCO) frequently show insulin resistance accompanied by an increase of IGF-1 in plasma. Plasma IGF-1 levels are higher in cases of severe endometriosis, however, in endometriosis and in PCO IGF levels locally in the endometrium are reduced, what might explain infertility. Recently, it was shown that IGF facilitates the implantation of the human embryo in the endometrium during IVF. Implantation is a paradox where different immune systems have to collaborate to make implantation and survival of the pregnancy possible. IGF seems to be the starter molecule so that the two epithelia can fuse. A disturbance can result in complications during pregnancy i.e. spontaneous miscarriage, preeclampsia as well as defects of the embryo. Therefore, IGF is a useful marker in successful pregnancy as well. A better mechanistic understanding of IGF-1 action on the cellular level not only provides more elegant mechanistic explanations for the scientist, but the practitioner might find it interesting to utilize its diagnostic potential as a marker for various diseases. The relation between systemic IGF levels and local tissue IGF-1 levels has not yet been determined for all conditions.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Fator de Crescimento Insulin-Like I/metabolismo , Neoplasias do Endométrio/genética , Endometriose/genética , Feminino , Humanos , Neoplasias Ovarianas/genética , Síndrome do Ovário Policístico/genética , Fatores de Risco , Saúde da Mulher
3.
Maturitas ; 33(1): 45-58, 1999 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-10585173

RESUMO

The aim of this study was to investigate the systemic bioavailability and plasma profiles of 17beta-estradiol (E2) after the application of three matrix patches for the transdermal delivery of E2: Menorest, Tradelia, and Estraderm MX claiming to deliver a dosage of 50 microg E2/day. All three patches were each worn randomly by 21 postmenopausal women volunteers over a 4-day period (i.e. 96 h). Each of the three treatment periods were separated by an at least 7 day wash out period according to a randomized, 3-way crossover design. Blood samples were taken from the antecubital vein before and 3, 6, 9, 12, 24, 28, 33, 48, 57, 72, 81, and 96 h after application. E2 plasma values were determined by a specific direct radioimmunoassay method. The following pharmacokinetic parameters were evaluated: AUC0-96h, Cmax, Tmax, Cmin, C(average). The time to reach the maximal E2 value of 32 h was the only pharmacokinetic parameter which was identical for all three patches. Menorest produced the highest E2 bioavailability judged by the AUC0-96h = 3967.8 +/- 1651.8 pg/ml, C(average) = 41.3 +/- 21.3 pg/ml, Cmin = 36.8 +/- 8.6 pg/ml. Tradelia showed statistically not significantly smaller C(average) = 38.9 +/- 17.0 pg/ml, AUC0-96h = 3737.9 +/- 1637.6 pg/ml x per h, and Cmin = 33.8 +/- 26.7 than Menorest. Estraderm MX showed lowest E2 plasma profiles Cmax = 38.9 +/- 25.1 pg/ml, C(average) = 33.2 +/- 17.1 pg/ml, AUC0-96 = 3192.1 +/- 1646.0 pg/ml per x h. Menorest showed the smallest fluctuation over the entire test period, similar to Estraderm MX, while Tradelia showed the highest E2-fluctuation (P < 0.01): Tradelia exhibited the highest Cmax = 48.0 +/- 20.3 pg/ml. When E2 baseline levels, prior to patch application are subtracted individually from the produced E2 plasma level, Estraderm MX is not bioequivalent to Menorest (P < 0.05). A circadian curve pattern of the E2 plasma level was observed for all patches: in the evening higher E2 plasma level were always detected compared with the morning, however, less pronounced with Estraderm MX. Individual comparison of AUC0-96h of each patch exhibited a large interindividual variability of 2000-8000 pg/ml per h for all three patches but relatively small individual variability: women with high E2 bioavailability (high responders) maintained high bioavailability in all applied patches, women identified as low and medium responders remained the same regardless of the applied patch. Menorest produced in 2/3 of all postmenopausal women with the highest E2 bioavailability (AUC0-96h), Tradelia was found in less than 1/3 (28.6%), and Estraderm MX in only one postmenopausal woman. Menorest only produced the highest reduction in postmenopausal symptoms together with Tradelia. Estraderm MX produced a smaller reduction in postmenopausal symptoms compared to Menorest and Tradelia. The observed side-effects were approximately equal in all three patches, with a maximum value after 72 h. It can be concluded that the three patches for the transdermal delivery of E2 claiming to deliver 50 microg E2/day differed from each other in their pharmacokinetic performance, although statistically not significant: Menorest exhibited the highest C(average), AUC and Cmin, and the lowest fluctuation, followed by Tradelia and Estraderm MX.


Assuntos
Estradiol/administração & dosagem , Estradiol/farmacocinética , Terapia de Reposição de Estrogênios , Pós-Menopausa/metabolismo , Administração Cutânea , Adulto , Idoso , Área Sob a Curva , Disponibilidade Biológica , Estudos Cross-Over , Estradiol/sangue , Feminino , Humanos , Pessoa de Meia-Idade
4.
J Pharm Sci ; 89(1): 115-27, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10664544

RESUMO

The aim of this study was twofold: Firstly, to compare the PS, the permeability surface product or organ clearance, of various hydrophilic molecules in the muscle blood capillary wall of different animal species, including humans and, secondly, to design an in vitro diffusion cell to identify similar PS values using the respective membranes. The flux rates of solutes with a wide range of molecular weights measured across porous membranes (Millipore(R) VM (MVM), and Nadir(R) UFC (NUFC)) was associated with high reproducibility (<+/-10% SD). The findings were as follows: (1) For the first time ever it was demonstrated that the log molecular weight dependency (between 180 and 10,000 Dalton) of the log of the PS product of the animal muscle capillary wall (slope = -0.51 +/- 0. 16, and a regression coefficient r(2) = 0.90) reported in the literature was similar to that observed by various authors in humans (slope = -0.50 +/- 0.25 r(2) = 0.77). (2) PS of the MVM membrane with a surface area of 3.8 cm(2) recorded for the newly developed diffusion cell ranged at approximately 50% below (slope -0.58 +/- 0. 12, r(2) = 0.85) the value observed in the in vivo human experiments after intramuscular injection. No linear relationship was established for the NUFC membrane due to solute exclusion effects of the membrane. (3) The diameter of the inner donor chamber (resembling the interstice between the muscle fiber membrane and the capillary wall membrane) was calculated to be sufficiently small to eliminate the possibility of creating a statistically significant diffusion barrier to the test membranes, which was corroborated by theoretical modeling. The structure of the in vitro diffusion cell prevents any significant contribution from the unstirred water layer (UWL) to overall resistance, thus reflecting in vivo diffusion properties of hydrophilic solutes deposited intramuscularly to enter the systemic circulation. It may be concluded, that MVM membrane in the vitro diffusion cell mimics the in vivo blood capillary PS for hydrophilic solutes of up to 10,000 Da.


Assuntos
Permeabilidade da Membrana Celular , Músculo Esquelético/irrigação sanguínea , Animais , Transporte Biológico , Capilares/metabolismo , Permeabilidade Capilar , Difusão , Humanos , Microdiálise , Modelos Biológicos , Porosidade , Propriedades de Superfície , Água/metabolismo
5.
Horm Mol Biol Clin Investig ; 8(2): 455-69, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25961344

RESUMO

Many cancer patients do not die due to impaired organ functions, but as a result of reduced general conditions, such as cachexia, sarcopenia, depression, infections, or stress. Reduced general health may be caused by immune modifying cytokines released from the tumor into the body. Improvement of immunity would not only reduce cancer side effects through inhibiting cytokine release from the tumor into the blood, but also, according to a new hypothesis, modify the cancer stem cells (CSC) in the tumor, which are believed to drive cancer growth and metastasis. We reported previously several investigations with a dietary fermented soy formulation (FSWW08) in cancer patients, where we saw a) strong reduction of cancer symptoms, b) broken resistance to chemotherapy, and c) a strong reduction of chemotherapy's toxic side effects, when taken in combination. This publication reports two new findings from a pilot study with postsurgical, treatment resistant patients conducted over four years. First, neither treatment resistance nor side effects were observed. Second, more patients have survived than expected. The improved health and immunity is detected together with increased CSC differentiation, suggesting lower aggressiveness, which was corroborated by increased gene expressions, particularly of steroidal hormones, MAPkinase, NF-κB, and tumor suppressor factor p53, a typical marker of "stemness" or cell differentiation. Although limited by its small, homogenous sample size, the results of this pilot study illustrate the relationship between CSCs differentiation, and the clinical symptoms of immunity, which influence survival outcomes and raise the clinical potential of measuring CSCs in ovarian, prostate, and breast cancers. The improved survival rates are also seen in larger cohort studies, which show similar gene expression profiles, which were induced by FSWW08 in the treatment resistant cancer patients in this study.

6.
Pharm Res ; 15(6): 877-82, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9647353

RESUMO

PURPOSE: The aim of our study was to investigate the high fluctuations of Estradiol (E2) plasma levels transdermally delivered in postmenopausal women by a commercially available membrane controlled reservoir system (MCRS). METHODS: The transdermal E2 flux either out of a complete MCRS or across its membrane out of defined ethanol water mixtures was determined, as well as E2 plasma profiles in 6 postmenopausal women produced by a MCRS. RESULTS: The transdermal in vitro E2 flux rate out of a complete MCRS, claimed to deliver 25 microg/day, increased steadily, reaching a maximum value of 2.06 +/- 0.58 microg/h at 30 to 40 hours and decreased to a rate of about 0.5 microg/h from 60 to 90 hours. No statistically significant differences between plasma profiles calculated from the in vitro investigation and derived from a clinical study could be identified. The E2 flux in defined ethanol/water mixtures across MCRS-membrane, adhesive and skin layer increased with increasing ethanol concentrations up to a maximum of 227 +/- 34 ng/cm2/h at an ethanol concentration of 62.5% (V/V) and decreased with further increase in the volume fraction of ethanol. CONCLUSIONS: In vitro as well as in vivo investigations showed high fluctuation of E2 plasma profiles in postmenopausal women produced by the MCRS. These fluctuations are caused by a non-constant input rate of E2 which may be due to changing ethanol concentrations in the reservoir of the MCRS.


Assuntos
Estradiol/farmacocinética , Administração Cutânea , Estradiol/administração & dosagem , Terapia de Reposição de Estrogênios , Feminino , Humanos , Técnicas In Vitro , Pessoa de Meia-Idade , Pós-Menopausa , Pele/metabolismo
7.
Zentralbl Gynakol ; 117(10): 531-9, 1995.
Artigo em Alemão | MEDLINE | ID: mdl-7491836

RESUMO

A novel patch containing 17 beta-Estradiol exhibits improved kinetic profiles compared to the currently available leading transdermal product. The blood concentrations produced by the newly developed matrix patch are stable over 3 to 4 days, thus avoiding the occurrence of 17 beta-Estradiol peaks in the blood. In an additional clinical study an almost linear relationship could be identified between the patch size (Test patch: 7.25, 14.5 and 29.0 cm2) and the obtained 17-estradiol bioavailability (judged on AUC, cmax, c(ave), Cmin). These results are corroborated by the additional in vitro experiments. An almost constant drug delivery rate of 48 micrograms +/- 15 micrograms/day of 17 beta-Estradiol per 13.85 cm2 patch over 4 days can be detected through excised human skin. No statistically significantly different transdermal flux rates of 17 beta-Estradiol were detected in 3 different batches of the transdermal drug delivery system in vitro. Statistical evaluations were performed with the 3-Way-Anova test on the 0.05 significance level. This newly developed product presents a kinetically optimized transdermal 17 beta-estradiol patch for hormone substitution therapy.


Assuntos
Climatério/sangue , Estradiol/farmacocinética , Terapia de Reposição de Estrogênios , Administração Cutânea , Idoso , Disponibilidade Biológica , Climatério/efeitos dos fármacos , Relação Dose-Resposta a Droga , Estradiol/administração & dosagem , Feminino , Humanos , Taxa de Depuração Metabólica/fisiologia , Pessoa de Meia-Idade , Absorção Cutânea/fisiologia
8.
Arzneimittelforschung ; 47(6): 761-7, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9239456

RESUMO

The aim of this study was to investigate the systemic bioavailability and plasma profiles of 17 beta-estradiol (CAS 50-28-2, E2) after the application of two types of matrix patches for the transdermal delivery of E2: MenorestTM (the test patch) with delivery rates of 37.5, 50 and 75 micrograms E2/day and a reference patch with a delivery rate of 50 micrograms E2/day. All 3 test patches were identical in composition, achieving different transdermal E2 delivery rates by variations in the surface area (11.0, 14.5 and 22.5 cm2). All 4 patches were each worn by 24 postmenopausal women over a 4-day period (i.e. 96 h), each of the 4 treatment periods being separated by a 7-day wash-out period according to a randomized, 4-way crossover design. Blood samples were collected before and 3, 6, 9, 12, 24, 34, 48, 58, 72, 84, and 96 h after each patch application. Plasma E2 concentrations were determined by a specific direct radioimmunoassay method. The following pharmacokinetic parameters were evaluated: AUC0-96h; Cmax, tmax, Cmin, Caverage. The course of the E2 plasma levels over the total test period (96 h) was relatively constant for all patches. For the test patch, a linear relationship between the pharmacokinetic parameters and the different patch areas (i.e. dosages of 37.5, 50, 75 micrograms E2/d) could be shown (correlation coefficient 0.99). The resulting Cmax values for the patch were: 44.2, 58.3, and 92.1 pg E2/ml, corresponding to Caverage values of 39.5, 45.5, and 70.6 pg E2/ml. The reference patch and the test patch, at a dose of 50 micrograms E2/d, were similar in terms of Cmax, while the Caverage, AUC0-96h and Cmin were significantly higher with the test patch. The systemic bioavailability of the reference patch was comparable to that of the test patch at a dose of 37.5 micrograms E2/d: AUC0-->96h 3017.5 +/- 1312.4 pg/ml.h for the reference patch and 3375.9 +/- 1254.7 pg/ml.h for the test patch. A physical model for the calculation of the course of the E2 levels was used to describe the experimentally determined data. However, in the evening, periodically higher E2 plasma levels were observed for all patches than in the morning. From these results it can be concluded that E2 plasma profiles produced by the test patch are reproducible, and in the physiological range consistent with the early to mid follicular level in the premenopausal woman over 4 days (96 h), correlating with the doses administered (37.5-50-75 micrograms E2/d). Additionally, the systemic bioavailability of the test patch at a dose of 37.5 micrograms E2/d is comparable to that of the reference patch at a dose of 50 micrograms E2/d.


Assuntos
Estradiol/farmacocinética , Administração Cutânea , Idoso , Disponibilidade Biológica , Ritmo Circadiano , Estudos Cross-Over , Estradiol/administração & dosagem , Estradiol/efeitos adversos , Estradiol/sangue , Feminino , Humanos , Pessoa de Meia-Idade
9.
Pharm Res ; 15(8): 1238-43, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9706055

RESUMO

PURPOSE: The aim of our study was to clarify the kinetic performance of a membrane controlled reservoir system (MCRS) for beta-estradiol (E2) under in vitro conditions by determination of the role of membrane and adhesive layer on E2 flux control. METHODS: E2 and ethanol fluxes across EVA membrane or membrane coated with adhesive from saturated solutions in defined ethanol/PBS mixtures were measured in the symmetric and asymmetric configuration. Physicochemical parameters of the EVA membrane were determined. RESULTS: The E2 flux across the 9% EVA membrane steadily increased with increasing ethanol concentrations in both configurations, due to enhanced uptake of E2 by the polymer and increasing membrane diffusivity. Permeation across the EVA membrane coated with an adhesive layer in symmetric and asymmetric configuration increased up to maximum values of 0.80+/-0.14 micrograms X cm-2 X h-1 and 0.37+/-0.02 micrograms X cm-2 X h-1, respectively, at 62.5% (v/v) ethanol. The fluxes then decreased with further increase in the volume fraction of ethanol due to a dramatically reduced permeability of the adhesive layer. For the asymmetric case, a linear dependence of E2 on the ethanol fluxes was observed. CONCLUSIONS: The E2 flux from MCRS is strictly dependent on reservoir ethanol concentrations, whereas the adhesive layer represents the rate controlling barrier at high ethanol levels (> 70% v/v).


Assuntos
Adesivos , Estradiol/administração & dosagem , Membranas Artificiais , Administração Cutânea , Estradiol/farmacocinética
10.
Zentralbl Gynakol ; 123(9): 505-12, 2001 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-11709743

RESUMO

OBJECTIVE: The aim of this randomized cross-over study was the comparison between a sequential 28-day hormone replacement therapy (HRT) using micronized estradiol and a cyclic 21-day HRT using estradiol valerate with regard to the pharmacokinetics of estradiol. - MATERIAL AND METHODS: Fifty postmenopausal women were randomly assigned to be treated either with Trisequens(R) for 28 days or with Sisare(R) for 21 days. After a wash-out cycle, the women were treated for one cycle with the other preparation in a cross-over fashion. The pharmacokinetic profile of the serum concentrations of estradiol was measured on day 1, 21 and 28 each immediately before and 1, 2, 4, 6, 8, and 10 hours after intake of a tablet, and the AUC (area under the curve) was calculated. - RESULTS: The serum concentrations of estradiol increased from a mean of 10 pg/ml up to 40 pg/ml (Trisequens(R)) and 30 pg/ml (Sisare(R)) on day 1, and to 80 pg/ml (Trisequens(R)) and 60 pg/ml (Sisare(R)) on day 21, and declined to 40 pg/ml (Trisequens(R)) and 10 pg/ml (Sisare(R)) on day 28. The AUC as calculated from both treatment cycles, was significantly higher on day 1, 21, and 28 during treatment with Trisequens(R) than with Sisare(R). This difference was, however, not signifcant on day 1 and 21 of the first treatment cycle. - CONCLUSION: During treatment with 2 mg micronized estradiol the serum concentrations are significantly higher than with 2 mg estradiol valerate. On day 28 of treatment with Sisare(R), the estradiol levels decline to baseline values, while using Trisequens(R) they remain in the range of those measured on day 1.


Assuntos
Estradiol/análogos & derivados , Estradiol/farmacocinética , Terapia de Reposição de Estrogênios/métodos , Noretindrona/análogos & derivados , Pós-Menopausa , Idoso , Anticoncepcionais Orais Sequenciais/farmacocinética , Estudos Cross-Over , Combinação de Medicamentos , Estradiol/sangue , Estriol/farmacocinética , Terapia de Reposição de Estrogênios/efeitos adversos , Feminino , Humanos , Imunoensaio/métodos , Medições Luminescentes , Pessoa de Meia-Idade , Noretindrona/farmacocinética
11.
Fundam Appl Toxicol ; 5(6 Pt 2): S112-21, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3912247

RESUMO

Experience in microvascular surgery on rats and availability of athymic (nude) rats led us to believe that a long-term functional rat/human skin sandwich flap could be generated on a defined and experimentally accessible vasculature on nude rats. Such a system has been developed and validated. Microvasculature has been assessed. The volume of blood to the flap ranges from 1 to 2 ml/min, collateral circulation to the flap exists, but is negligible, and there is little change in the capillary blood flow as the flap ages. The flap can be utilized to study absorption of compounds from a half-cell diffusion chamber or from direct deposition on the skin, and can be utilized to study various parameters of percutaneous absorption, e.g., the effect of hydration on the stratum corneum. Transdermal flux can be determined. Altering the microcirculation directly affects the percutaneous absorption of compounds that are rapidly absorbed. The absorption of benzoic acid through an experimentally vasoconstricted area (iontophoresis of phenylephrine) significantly alters the time to peak absorption, with values being 14 times that of the control site. The system has been utilized to assess metabolic activity of skin in situ using [3H]adenine arabinoside and studying the appearance of its major metabolite, [3H]Ara-H, in flap blood, as well as the back diffusion of this compound into the donor chamber. Recently the human/rat skin sandwich flap component has been developed. With this system, it has been demonstrated that benzoic acid, when applied to the human skin component of the flap has an absorption profile which is quite different from that when benzoic acid is applied to rat skin, peak flux occurred 2 hr after application. This contrasts with 10 min to peak flux when the same experiment is carried out on the rat/rat skin sandwich flap. To our knowledge, the human/rat skin sandwich flap is the first example of a viable, functional human organ that is chronically maintained by a biologic support system which has the added distinction of being on an independent but accessible vasculature. The validation experiments strongly suggest that this system will be important in gaining insights into the more sophisticated in vivo components of skin, relative to toxicology and pharmacology.


Assuntos
Pele/irrigação sanguínea , Animais , Difusão , Humanos , Iontoforese , Microcirculação , Modelos Biológicos , Ratos , Fluxo Sanguíneo Regional , Pele/metabolismo , Absorção Cutânea , Transplante de Pele , Fatores de Tempo , Transplante Heterólogo
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