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1.
Men with classical androgen deficiency have reduced prostate volume and blood prostate-specific antigen (PSA) levels compared with their age peers. As it is plausible that androgen deficiency partially protects against prostate disease, and that restoring androgen exposure increases risk to that of eugonadal men of the same age, men using ART should have age-appropriate surveillance for prostate disease. This should comprise rectal examination and blood PSA measurement at regular intervals (determined by age and family history) according to the recommendations, permanently revisited, published by ISSAM, EAU, Endocrine Society…. Testosterone replacement therapy is now being prescribed more often for aging men, the same population in which prostate cancer incidence increases; it has been suggested that administration in men with unrecognised prostate cancer might promote the development of clinically significant disease. In hypogonadal men who were candidates for testosterone therapy, a 14% incidence of occult cancer was found. A percentage (15.2%) of prostate cancer has been found in the placebo group (with normal DRE and PSA) in the prostate cancer prevention study investigating the chemoprevention potential of finasteride. The hypothesis that high levels of circulating androgens is a risk factor for prostate cancer is supported by the dramatic regression, after castration, of tumour symptoms in men with advanced prostate cancer. However these effects, seen at a very late stage of cancer development, may not be relevant to reflect the effects of variations within a physiological range at an earlier stage. Data from all published prospective studies on circulating level of total and free testosterone do not support the hypothesis that high levels of circulating androgens are associated with an increased risk of prostate cancer. A study on a large prospective cohort of 10,049 men, contributes to the gathering evidence that the long standing “androgen hypothesis” of increasing risk with increasing androgen levels can be rejected, suggesting instead that high levels within the reference range of androgens, estrogens and adrenal androgens decrease aggressive prostate cancer risk. Indeed, high-grade prostate cancer has been associated with low plasma level of testosterone. Furthermore, pre-treatment total testosterone was an independent predictor of extraprostatic disease in patients with localized prostate cancer; as testosterone decreases, patients have an increased likelihood of non-organ confined disease and low serum testosterone levels are associated with positive surgical margins in radical retropubic prostatectomy. A clinical implication of these results concerns androgen supplementation which has become easier to administer with the advent of transdermal preparations (patch or gel) that achieve physiological testosterone serum levels without supra physiological escape levels. During the clinical development of a new testosterone patch in more than 200 primary or secondary hypogonadal patients, no prostate cancer was diagnosed. 相似文献
2.
类风湿关节炎(RA)是全世界难治性自身免疫疾病,其治疗药物虽不断发展,但病灶药物浓度达不到有效水平导致药物疗效不理想或存在各种毒副反应,因此,基于新技术、新方法研究开发针对RA的安全、高效新型制剂是必要的.研究表明,纳米技术的运用可提高药物生物利用度,经皮给药可改善口服和注射带来的毒副作用.对近年来基于经皮给药系统治疗... 相似文献
3.
Transdermal delivery systems are useful in cases where preferred routes such as the oral route are not available. However, low overall extent of delivery is seen due to the permeation barrier posed by the skin. Chemical penetration enhancers and invasive methods that disturb the structural barrier function of the skin can be used to improve transdermal drug delivery. However, for suitable drugs, a fast-releasing transdermal delivery system can be produced by incorporating a heating source into a transdermal patch. In this study, a molecular dynamics simulation showed that heat increased the diffusivity of the drug molecules, resulting in faster release from gels containing ketoprofen, diclofenac sodium, and lidocaine HCl. Simulations were confirmed by in vitro drug release studies through lipophilic membranes. These correlations could expand the application of heated transdermal delivery systems for use as fast-release-dosage forms. 相似文献
4.
In clinical trials, transdermal oxybutynin (OXY-TDS) has shown comparable efficacy and improved tolerability when compared with conventional pharmacotherapy. Systemic anticholinergic adverse effects are comparable to those with placebo, most likely owing to avoidance of first-pass hepatic metabolism and conversion of oxybutynin to N-desethyloxybutynin. OXY-TDS has predictable pharmacokinetic absorption and elimination parameters, as shown in both in vitro and in vivo studies. Consistent plasma concentrations of oxybutynin avoid labile peak and trough concentrations seen with immediate-release formulations, paralleling extended-release drug delivery. This novel drug delivery system has unique dermatologic skin application site reactions, including erythema and pruritus. Skin reactions are usually mild and can be minimized by varying the site of patch application. Most eczematous dermatologic reactions can be appropriately treated with a moderately potent topical corticosteroid cream. A small percentage of patients will discontinue therapy as a result of bothersome application site skin reactions. 相似文献
5.
The aim of this work was to evaluate capability of site-specific delivery of a transdermal patch through determination of
letrozole in local tissues disposition in female mice. After transdermal administration, the letrozole levels in skin, muscle,
and plasma were 10.4–49.3 μg/g, 1.64–6.89 μg/g, and 0.35–1.64 μg/mL, respectively. However, after the mice received letrozole
suspension, the drug concentration of plasma and muscle were 0.20–4.80 μg/mL and 0.15–2.38 μg/g. There was even no drug determined
in skin through all experiments. Compared with oral administration, the transdermal patch for site-specific delivery of letrozole
could produce high drug concentrations in skin and muscle and meanwhile obtain low drug level in plasma. These findings show
that letrozole transdermal patch is an appropriate delivery system for application to the breast tumor region for site-specific
drug delivery to obtain a high local drug concentration and low circulating drug concentrations avoiding the risk of systemic
side effects. 相似文献
6.
ObjectiveTo examine the association of various gender-affirming hormone therapy regimens with blood sex hormone concentrations in transgender individuals. MethodsThis retrospective study included transgender people receiving gender-affirming hormone therapy between January 2000 and September 2018. Data on patient demographics, laboratory values, and hormone dose and frequency were collected. Nonparametric tests and linear regression analyses were used to identify factors associated with serum hormone concentrations. ResultsOverall, 196 subjects (134 transgender women and 62 transgender men), with a total of 941 clinical visits, were included in this study. Transgender men receiving transdermal testosterone had a significantly lower median concentration of serum total testosterone when compared with those receiving injectable preparations (326.0 ng/dL vs 524.5 ng/dL, respectively, P = .018). Serum total estradiol concentrations in the transgender women were higher in those receiving intramuscular estrogen compared with those receiving oral and transdermal estrogen (366.0 pg/mL vs 102.0 pg/mL vs 70.8 pg/mL, respectively, P < .001). A dose-dependent increase in the hormone levels was observed for oral estradiol ( P < .001) and injectable testosterone ( P = .018) but not for intramuscular and transdermal estradiol. Older age and a history of gonadectomy in both the transgender men and women were associated with significantly higher concentrations of serum gender-affirming sex hormones. ConclusionIn the transgender men, all routes and formulations of testosterone appeared to be equally effective in achieving concentrations in the male range. The intramuscular injections of estradiol resulted in the highest serum concentrations of estradiol, whereas transdermal estradiol resulted in the lowest concentration. There was positive relationship between both oral estradiol and injectable testosterone dose and serum sex hormone concentrations in transgender people receiving GAHT. 相似文献
7.
With aging in men, serum testosterone levels decline progressively and the prevalence of hypogonadism increases; these changes are associated with alterations in androgen-regulated physiological functions. In young hypogonadal men, similar alterations improve with testosterone replacement. In older men, short-term testosterone treatment trials suggest benefits (eg, on body composition and bone mineral density), without significant adverse effects. Therefore, androgen deficiency may contribute to physiological decline with aging, and testosterone therapy is reasonable for older men with clinical manifestations of androgen deficiency and low testosterone levels. However, the long-term benefits and potential risks (eg, for prostate disease) of testosterone treatment in older men are unknown. 相似文献
8.
The objective of the present study was to develop membrane-moderated transdermal systems of ampicillin sodium and to evaluate
them with respect to various in vitro and in vivo parameters. The membrane-type transdermal systems were prepared using a
drug with various antinucleant polymers— hydroxypropyl methylcellulose (HPMC), methylcellulose (MC), cellulose acetate phthalate,
chitosan, sodium alginate (SA), and sodium carboxymethylcellulose—in an ethanol: pH 4.7 buffer volatile system by the solvent
evaporation technique with HPMC as the rate-controlling membrane for all the systems. The swelling properties of the polymers
were studied, and drug-polymer interaction studies were performed. The patches were subjected to various physicochemical studies,
in vitro release studies, permeation studies, and skin irritation studies. The best patch among the formulations was selected
for further in vivo studies. Compared to the other patches, SA exhibited the highest moisture content at 16%; a 21% moisture
uptake was found with MC. The release and permeation of the drug from the SA patch was found to be the maximum. The in vivo
study of the SA patch exhibited a peak plasma concentration C max of 126 μg/mL at T max 4 hours. Hence, it can be concluded that hydrophilic ampicillin sodium can be developed as a transdermal delivery system
with SA that is an alternative to intravenous administration and has minimal adverse effects.
Published: January 26, 2007 相似文献
9.
Androgen deprivation therapy (ADT) is part of standard therapy for locally advanced or metastatic prostate cancer and is frequently used in men with a rising prostate-specific antigen following radical prostatectomy or radiation therapy. In some men, ADT may be administered for years or even decades. The intended therapeutic effect of ADT is testosterone deficiency. Because estrogen is a normal metabolite of testosterone, ADT also results in estrogen deficiency. ADT has a variety of adverse effects, many of which are primarily related to estrogen deficiency. Bone mineral density may decrease by 4% to 13% per year in men receiving ADT. The fracture rate for patients on ADT averages 5% to 8% per year of therapy. Hot flashes, gynecomastia, and breast tenderness are common side effects associated with ADT. In the clinic, minimum baseline testing should include weight measurement, blood pressure reading, and fasting lipid panel and serum glucose tests. Currently, there are no large outcome trials in men on ADT testing the available therapies for adverse effects. No therapies are specifically approved for treatment of adverse effects in men on ADT. Although some therapies can be used for a single indication (based upon small studies), there is currently no agent to treat the multiple estrogenic side effects of ADT. 相似文献
10.
The transdermal patch formulation has many advantages, including noninvasiveness, an ability to bypass the first-pass metabolism, low dosage requirements, and prolonged drug delivery. However, the instability of solid-state drugs is one of the most critical problems observed in transdermal patch products. Therefore, a well-characterized approach for counteracting stability problems in solid-state drugs is crucial for improving the performance of transdermal patch products. This review provides insight into the solid-state stability of drugs associated with transdermal patch products and offers a comprehensive update on the various approaches being used for improving the stability of the active pharmaceutical ingredients currently being used. 相似文献
11.
The most popular therapeutic option in the management of radio-recurrent prostatic carcinoma is represented by the androgen deprivation therapy, that however should be considered only palliative and hampered by potential adverse effects of testosterone suppression. Local therapies such as surgery, cryoablation or brachytherapy might be curative choices for patients in good conditions and with a long-life expectancy, but at cost of significant risk of failure and severe toxicity. The administration of stereotactic body radiation therapy (SBRT) in this setting have come about because of tremendous technologic advances in image guidance and treatment delivery techniques that enable the delivery of large doses to tumor with reduced margins and high gradients outside the target, thereby reducing the volume of rectum which already received significant doses from primary radiotherapy. So far, very modest data are available to support its employment. Rationale, clinical experience, and challenges are herein reviewed and discussed. 相似文献
12.
A new transdermal preparation, Testim(R) 1% testosterone gel, has recently become available for normalization of serum testosterone in hypogonadal men. In short-term studies, it has been shown to reverse the clinical signs and symptoms of low testosterone and to be well tolerated with less applicationsite irritation than with testosterone patches. In 2 long-term studies with Testim, the predose early morning serum testosterone (T), dihydrotestosterone (DHT), and free testosterone (FT) levels were assessed. Serum T, DHT, and FT were all maintained in the normal range for up to 12 months. In these studies, involving a total of 371 hypogonadal men, evaluation by means of dual-energy x-ray absorptiometry revealed a significant increase from baseline in bone mineral density. A significant improvement was also observed in body composition (increased lean body mass, decreased fat mass, and decreased percentage fat). In addition, significant improvements in mood and sexual function were maintained for up to 12 months of treatment. The parameters measured included sexual performance, sexual motivation, sexual desire, and occurrence of spontaneous erections. These data from the 2 long-term studies support the results of the 90-day studies with Testim showing that the gel significantly improves the signs and symptoms associated with low testosterone compared with placebo. The data also support the conclusion that these improvements are maintained for up to 1 year of additional treatment. 相似文献
13.
The effects of androgens on cardiovascular disease (CVD) risk in men remain unclear. To better characterize the relationship between androgens and HDL, we investigated the effects of testosterone replacement on HDL protein composition and serum HDL-mediated cholesterol efflux in hypogonadal men. Twenty-three older hypogonadal men (ages 51-83, baseline testosterone < 280 ng/dl) were administered replacement testosterone therapy (1% transdermal gel) with or without the 5α-reductase inhibitor dutasteride. At baseline and after three months of treatment, we determined fasting lipid concentrations, HDL protein composition, and the cholesterol efflux capacity of serum HDL. Testosterone replacement did not affect HDL cholesterol (HDL-C) concentrations but conferred significant increases in HDL-associated paraoxonase 1 (PON1) and fibrinogen α chain (FGA) (P = 0.022 and P = 0.023, respectively) and a decrease in apolipoprotein A-IV (apoA-IV) (P = 0.016). Exogenous testosterone did not affect the cholesterol efflux capacity of serum HDL. No differences were observed between men who received testosterone alone and those who also received dutasteride. Testosterone replacement in older hypogonadal men alters the protein composition of HDL but does not significantly change serum HDL-mediated cholesterol efflux. These effects appear independent of testosterone conversion to dihydrotestosterone. Further research is needed to determine how changes in HDL protein content affect CVD risk in men. 相似文献
14.
ObjectiveThis narrative review offers a guideline-based approach for optimizing diagnostic evaluation and treatment decision making in men being evaluated for testosterone deficiency. MethodsA narrative review. ResultsTestosterone deficiency is a clinical syndrome that results from the inability of the testes to produce normal amounts of testosterone and is characterized by a constellation of symptoms and signs associated with consistently low testosterone concentrations. The diagnosis of testosterone deficiency is made by the ascertainment of symptoms and signs; the measurement of total and, if indicated, free testosterone levels in early-morning fasting samples on ≥2 days; the measurement of luteinizing hormone and follicular-stimulating hormone levels to distinguish primary from secondary hypogonadism; and an additional evaluation to ascertain the cause of testosterone deficiency. Nonspecificity of symptoms and signs, variations in testosterone levels over time, inaccuracy in the measurement of total and free testosterone levels, variations in binding protein concentrations, and suboptimal reference ranges contribute to diagnostic inaccuracy. Testosterone treatment is indicated for men with symptomatic testosterone deficiency. Testosterone treatment should be avoided in men with prostate or breast cancer, erythrocytosis, thrombophilia, increased risk of prostate cancer or severe lower urinary tract symptoms without prior urologic evaluation, a recent major adverse cardiovascular event, uncontrolled heart failure, or severe untreated sleep apnea. Testosterone replacement therapy should be accompanied by a standardized monitoring plan. ConclusionA shared decision of the patient and physician to treat should be guided by the consideration of the burden of symptoms, potential benefits and risks, patient’s values, and the cost and burden of long-term treatment and monitoring. 相似文献
15.
Finasteride, a 4-aza steroid compound, is an orally active inhibitor of the 5 alpha-reductase enzyme. 5 alpha-Reductase is necessary for the metabolism of testosterone (T) to dihydrotestosterone (DHT) and is found in high levels only in certain tissues such as the prostate. Finasteride has been shown to markedly suppress serum DHT levels in man without lowering testosterone levels. In patients with benign prostate hyperplasia (BPH), finasteride was found to decrease prostate volume by a mean of 28% over a period of 6 months, without causing clinically significant adverse effects. DHT appears to be the primary androgen for prostatic growth. Selective inhibition of 5 alpha-reductase by finasteride may provide a novel approach to BPH therapy by reducing prostate size without affecting T-dependent processes such as fertility, muscle strength, and libido. The clinical development of finasteride for the treatment of benign prostate hyperplasia is reviewed. 相似文献
16.
Serum steroids profiles were determined at different stages of the migratory cycle of Russian sturgeon. In the sea period, before gonads maturation cortisol and sex steroids levels were comparatively low. Elevation of cortisol and testosterone concentrations occurred at the stage of preparation to migration. Significant increase of cortisol and testosterone levels happened at the beginning of the river period of anadromous migration in spring both in the spring forms near to maturity in this period and in the winter forms which were far from maturity. By exception of the river period of anadromous migration of the winter form and sexual cycle completion in the fish farm in the mouth of river (10-11 months), serum cortisol and testosterone concentrations dropped sharply. The data obtained as well as the data on other diadromous fishes indicate a possible role of steroids, especially cortisol and testosterone, in metabolism and migration regulation in sturgeons. 相似文献
17.
The iron chelator, deferoxamine (DFO), has been shown to potentially improve dermal radiation-induced fibrosis (RIF) in mice through increased angiogenesis and reduced oxidative damage. This preclinical study evaluated the efficacy of two DFO administration modalities, transdermal delivery and direct injection, as well as temporal treatment strategies in relation to radiation therapy to address collateral soft tissue fibrosis. The dorsum of CD-1 nude mice received 30 Gy radiation, and DFO (3 mg) was administered daily via patch or injection. Treatment regimens were prophylactic, during acute recovery, post-recovery, or continuously throughout the experiment ( n = 5 per condition). Measures included ROS-detection, histology, biomechanics and vascularity changes. Compared with irradiated control skin, DFO treatment decreased oxidative damage, dermal thickness and collagen content, and increased skin elasticity and vascularity. Metrics of improvement in irradiated skin were most pronounced with continuous transdermal delivery of DFO. In summary, DFO administration reduces dermal fibrosis induced by radiation. Although both treatment modalities were efficacious, the transdermal delivery showed greater effect than injection for each temporal treatment strategy. Interestingly, the continuous patch group was more similar to normal skin than to irradiated control skin by most measures, highlighting a promising approach to address detrimental collateral soft tissue injury following radiation therapy. 相似文献
18.
The signs and symptoms of low testosterone in the aging male include erectile dysfunction, decreased libido, mood disturbances such as depression, loss of muscle mass, osteoporosis, and increase in body fat. Many of these signs and symptoms were previously believed to be part of the normal aging process, and only recently has treatment of low testosterone in the aging male been shown to provide long-term physical and mental improvement. In the past, oral and injectable testosterone delivery methods had disadvantages that limited their use, but the introduction of transdermal testosterone patches has allowed testosterone to be delivered into the circulation in a consistent fashion. Long-term use of these patches over the last 3 to 10 years has been effective in maintaining sexual function and bone and muscle mass, and from short-term studies it does not appear that testosterone treatment puts men at risk for the development of prostate cancer. A new topical gel formation (Testim) has been designed to provide consistent transdermal absorption of testosterone over 24 hours after a single dose. 相似文献
19.
Exogenous androgens can lower HDL-cholesterol (HDL-C) concentrations, yet men with low serum testosterone have elevated rates of cardiovascular disease (CVD). HDL function may better predict CVD risk than absolute HDL-C quantity. We evaluated the acute effects of medical castration in men on HDL-C, cholesterol efflux capacity and HDL protein composition. Twenty-one healthy men, ages 18-55, received the GnRH antagonist acyline and one of the following for 28days: Group 1: placebo, Group 2: transdermal testosterone gel and placebo, Group 3: transdermal testosterone gel and an aromatase inhibitor. Sex steroids, fasting lipids, and cholesterol efflux to apoB-depleted serum were measured in all subjects. The HDL proteome was assessed in Group 1 subjects only. In Group 1, serum testosterone concentrations were reduced by >95%, and HDL-C and cholesterol efflux capacity increased (p=0.02 and p=0.03 vs. baseline, respectively). HDL-associated clusterin increased significantly with sex steroid withdrawal (p=0.007 vs. baseline). Testosterone withdrawal in young, healthy men increases HDL-C and cholesterol efflux capacity. Moreover, sex steroid deprivation changes HDL protein composition. Further investigation of the effects of sex steroids on HDL composition and function may help resolve the apparently conflicting data regarding testosterone, HDL-C, and CVD risk. 相似文献
20.
There is increasing interest in the assessment of testicular function in aging men, probably because of an increasing number of males above 60 years and because of the emerging gap in the medical management of aging between men and women. In the last three decades, the endocrinological problems of menopause have been thoroughly taken into consideration, while the decline in testis activity in the so called andropause was only recently recognized to deserve a similar interest. In fact, testis endocrine function is not so easy to evaluate in elderly men: total testosterone (tT) level declines very slowly and it is a fallacious index of testis function because of the increase in testosterone/estradiol binding globulin (TeBG) levels in aging males. Free testosterone level is an accurate index when measured by reference techniques, while routine direct assays using testosterone analogues have been proven to be unreliable diagnostic tools. The measurement of bioavailable testosterone (bT) after ammonium sulfate precipitation of TeBG-bound testosterone is currently considered as the method of choice for diagnosing ADAM syndrome. Indeed, in aging males, bT levels are more closely correlated than tT with bone mineral density, muscle strength and muscle mass. Bioavailable estradiol is also a reliable index of testis aging in elderly males and is strongly correlated with bone mineral density. Unfortunately a serious expertise is needed for accurate measurement of bioavailable estradiol levels. Another difficulty in the diagnosis of ADAM syndrome in the uncertainty in the bT threshold to be taken into account. The 5th percentile of bT levels in young adult men can be arbitrarily choosen; however, there is no definite proof that such a threshold is totally appropriate, since no data are available regarding the evolution with years of androgen receptor sensitivity. Nevertheless, identifying androgen deficiency by means of bT measurement may lead to hormone replacement therapy, at least as a therapeutic test. Several formulations of testosterone are currently available using oral, intra-muscular and transdermal routes. Testosterone undecanoate (Pantestone®) is given orally and is supposed to reach the blood stream via the lymph thoracic channel. Intra-muscular testosterone in oil (Androtardyl® and Testosterone Heptylate®) can maintain high testosterone levels for two to three weeks, but can also induce supra-physiological levels of testosterone and dihydrotestosterone (DHT) within the first week after injection. Transdermal formulations have been recently proposed as non-invasive ways to administer testosterone while by-passing liver metabolism. Permeation enhanced transdermal system (Androderm®) can mimic the testosterone circadian rythm, but testosterone levels may be supra-physiological for several hours. DHT levels however are generally maintained whithin physiological values. Testosterone gel (Androgel®) can induce stable and physiological levels of testosterone, DHT and estradiol. Care should be taken to avoid contamination of the familial environment by testosterone after its application. The choice between these formulations depends obviously on the patient’s needs, the patient’s requests, and the patient’s compliance with a particular formulation. 相似文献
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