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51.
Reverse electrodialysis (RED) technology generates energy from the salinity gradient by contacting waters with different salinity. Herein, we develop the disposable skin patch using this eco-friendly energy. The current density, which can be controlled easily without special circuit, is enough to iontophoretic drug delivery. In vitro study, this iontophoretic system enhanced the transdermal delivery of peptide, which is difficult to penetrate the skin barrier by simple diffusion. We design the disposable iontophoretic skin patch using RED system and suggest this patch can be apply on new cosmetic patch or disposable drug patch.  相似文献   
52.
Sixty-four patients with persistent asthma receiving 200 to 800 μ g of fluticasone propionate daily were enrolled in this switchover study. The patients applied a tulobuterol patch 2 mg every 24 hours for 4 weeks followed by inhalation of salmeterol 100 μ g bid for 4 weeks. The mean values for morning and evening peak expiratory flow improved significantly compared with baseline during the 4 weeks of tulobuterol patch treatment. Further improvement was seen on switching to salmeterol treatment, which was significant even in the first week, and continued until the final week of the study. Use of salmeterol alone resulted in a significant increase in the percentage of forced expiratory volume in 1 second %FEV1 from baseline, with 51% of patients feeling that the treatment was effective (vs. 37% on tulobuterol). These data suggest that salmeterol can achieve better control in asthmatic patients after switching from using tulobuterol patches.  相似文献   
53.
The selegiline transdermal system (STS) is being developed to treat major depressive disorder. In a Phase I clinical study, the STS (20 mg/20 cm2) produced mild dermal irritability and demonstrated a low potential for contact allergenicity. In Phase III multicenter studies in major depression, over 1800 patients have been evaluated for dermal safety to reveal an overall rate of application site reactions (ASRs) with STS of 21.8% compared with a placebo rate of 9.7%. Discontinuation rates due to dermal adverse events in clinical studies were low (3.5%). Overall, the STS demonstrated good tolerability regarding ASRs and the potential for delayed contact hypersensitivity.  相似文献   
54.
The aim of this paper is to investigate the effects of hydrogel mesh size, a conductive polymer, and electric field strength on controlled drug delivery phenomena using drug-loaded polyacrylamide hydrogels prepared at various crosslinking ratios both with and without a conductive polymer system. Poly(p-phenylene vinylene), PPV, as the model conductive polymer, was used to study its ability to control aloin released from aloin-doped poly(p-phenylene vinylene)/polyacrylamide hydrogel (aloin-doped PPV/PAAM). In the passive release, the diffusion of aloin from five aloin-doped PPV/PAAM hydrogel systems each was delayed ranging from during the first three hours to during the first 14 h due to the ionic interaction between the anionic drug and PPV. After the delayed periods, aloin could diffuse continuously into the buffer solution through the PAAM matrix. The amount of aloin released from the aloin-doped PPV/PAAM rose with increasing electric field strength as a result of the three mechanisms: the expansion of PPV chains inside the hydrogel, iontophoresis, and the electroporation of the matrix pore size, combined. Furthermore, the conductive polymer and the electric field could be used in combination to regulate the amount of release drug to a desired level, to control the release rate, and to switch the drug delivery on/off.  相似文献   
55.
Aims   The primary aim was to compare the efficacy of smoking cessation treatment using a combination of active nicotine patch plus active nicotine gum versus therapy consisting of active nicotine patch plus placebo gum in a sample of alcohol-dependent tobacco smokers in an early phase of out-patient alcohol treatment. A secondary aim was to determine whether or not there were any carry-over effects of combination nicotine replacement on drinking outcomes.
Design   Small-scale randomized double-blind placebo-controlled clinical trial with 1-year smoking and drinking outcome assessment.
Setting   Two out-patient substance abuse clinics provided a treatment platform of behavioral alcohol and smoking treatment delivered in 3 months of weekly sessions followed by three monthly booster sessions.
Participants   Participants were 96 men and women with a diagnosis of alcohol abuse or dependence and smoking 15 or more cigarettes per day.
Intervention   All participants received open-label transdermal nicotine patches and were randomized to receive either 2 mg nicotine gum or placebo gum under double-blind conditions.
Findings   Analysis of 1-year follow-up data revealed that patients receiving nicotine patch plus active gum had better smoking outcomes than those receiving patch plus placebo gum on measures of time to smoking relapse and prolonged abstinence at 12 months. Alcohol outcomes were not significantly different across medication conditions.
Conclusions   Results of this study were consistent with results of larger trials of smokers without alcohol problems, showing that combination therapy (nicotine patch plus gum) is more effective than monotherapy (nicotine patch) for smoking cessation.  相似文献   
56.
The systemic hemodynamic and coronary dilative responses to sublingual nitroglycerin were studied in patients receiving transdermal nitroglycerin. A total of 48 patients with coronary artery disease were divided into 4 groups: 12 patients receiving 1 tablet of sublingual nitroglycerin without transdermal nitroglycerin (Group 1), 12 patients receiving 1 tablet of sublingual nitroglycerin with 12-hour-daily intermittent therapy of transdermal nitroglycerin (Group 2), 12 patients receiving 1 tablet of sublingual nitroglycerin with continuous therapy of transdermal nitroglycerin (Group 3), and 12 patients receiving 2 tablets of sublingual nitroglycerin with continuous therapy of transdermal nitroglycerin (Group 4). Before and during administration of sublingual nitroglycerin, aortic pressure, left ventricular pressure, and coronary artery diameter were examined at diagnostic cardiac catheterization in all patients. During sublingual nitroglycerin, the decreases of aortic systolic pressure and left ventricular end-diastolic pressure were greater in Group 1, 2, and 4 than in Group 3. Dilation of coronary arteries by sublingual nitroglyerin tended to be greater in Group 1, 2, and 4 than in Group 3. Thus, the effects of sublingual nitroglycerin for the relief of ischemia might be more prominent in patients with intermittent therapy of transdermal nitroglycerin than in those with continuous therapy. The increased dose of sublingual nitroglycerin for the relief of ischemia might be more effective in patients with continuous therapy of transdermal nitroglycerin.  相似文献   
57.
紫杉醇纳米脂质体凝胶剂的制备及体外透皮研究   总被引:3,自引:3,他引:0  
目的制备紫杉醇纳米脂质体凝胶剂,考察其粒径、粒径分布、包封率、体外释放度及透皮特性。方法采用薄膜蒸发高压微射流法制备紫杉醇纳米脂质体,以卡波姆为凝胶基质,研制紫杉醇纳米脂质体凝胶剂,采用正交试验探索最佳工艺。用粒径测定仪测定脂质体的粒径及其粒径分布,低速-超速相结合法测定包封率,透析膜扩散法进行体外释放试验,以离体小鼠皮结合改良Franz扩散装置考察其体外透皮特性。结果紫杉醇纳米脂质体的最佳工艺:卵磷脂的含量为2%,药物与磷脂质量比为1∶30,磷脂与胆固醇的质量比为10∶1。测得的粒径为81.8 nm;粒径分布系数为0.180;平均包封率73.2%。纳米脂质体凝胶剂72 h累积释放百分率为79.04%;48 h的单位面积累积渗透量为429.68μg·cm?2。结论该制剂制备工艺简单,易于涂布,具有较高的包封率,粒径较小且分布均匀,体外释放缓慢。纳米脂质体能促进脂溶性药物紫杉醇透过皮肤。  相似文献   
58.
Objective: Investigate safety, feasibility and efficacy of switching therapy in patients with advanced-stage Parkinson’s disease (PD) inadequately controlled with pramipexole (≤ 3.5 mg/day) or ropinirole (≤ 14 mg/day) to rotigotine transdermal system (≤ 14 mg/24 h; dose adjustments ≤ 16 mg/24 h permitted).

Methods: PD0009 (ClinicalTrials.gov: NCT01711866) was an open-label study in patients with advanced-stage PD receiving levodopa, and experiencing sleep disturbance or early-morning motor impairment. Pramipexole/ropinirole was switched to equivalent dose rotigotine overnight or in two stages. During the 4-week treatment period rotigotine dose adjustments were permitted (up to 16 mg/24 h). Primary variable: Clinical Global Impressions (CGI) item 4: side effects (assessing safety) at end of treatment.

Results: 79/87 (91%) patients completed the study; 2 (2%) withdrew due to adverse events (AEs). Most (84; 97%) had CGI item 4 score < 3 indicating switch did not interfere with functioning; three experienced drug-related AEs interfering with functioning (score = 3). 62% patients improved on Patient Global Impression of Change, assessing effectiveness. AEs occurring ≥ 5%: application site pruritus (10%), application site erythema (7%), dizziness (7%), dyskinesia (7%), erythema (6%), pruritus (6%). Unified Parkinson’s Disease Rating Scale II and III, Parkinson’s Disease Sleep Scale-2 and Pittsburgh Sleep Quality Index were unchanged. Numerical improvements in ‘off’ time, awakenings and nocturias were observed.

Conclusions: Switch from pramipexole or ropinirole to rotigotine (up to 14 mg/24 h) was feasible and possibly associated with some benefit.  相似文献   

59.

Objective

We investigated patient and disease characteristics predictive of relapse of MDD during a 52-week placebo controlled trial of selegiline transdermal system (STS) to identify patient characteristics relevant for STS treatment.

Method

After 10 weeks of open-label stabilization with STS, 322 remitted patients with MDD were randomized to 52-weeks of double-blind treatment with STS (6 mg/24 h) or placebo (PLB). Relapse was defined as Hamilton Depression Rating Scale (HAMD-17) score of ≥14 and a CGI-S score of ≥3 with at least 2-point increase from the beginning of the double blind phase on 2 consecutive visits. Cox's proportional hazards regression was used to examine the effect of potential predictors (age, sex, age at onset of first MDD, early response pattern, number of previous antidepressant trials, severity of index episode, number of previous episodes, melancholic features, atypical features and anxious feature) on outcome. Exploratory analyses examined additional clinical variables (medical history, other psychiatric history, and individual items of HAM-D 28) on relapse.

Results

For all predictor variables analyzed, treatment Hazard Ratio (HR=0.48~0.54) was significantly in favor of STS (i.e., lower relapse risk than PLB). Age of onset was significantly predictive of relapse. Type, duration, and severity of depressive episodes, previous antidepressant trials, or demographic variables did not predict relapse. In additional exploratory analysis, eating disorder history and suicidal ideation were significant predictors of relapse after controlling for the effect of treatment in individual predictor analysis.

Conclusions

While age of onset, eating disorder history and suicidal ideation were significant predictors, the majority of clinical and demographic variables were not predictive of relapse. Given the post-hoc nature of analysis, the findings need confirmation from a prospective study. It appears that selegiline transdermal system was broadly effective in preventing relapse across different subtypes and symptoms clusters of MDD.  相似文献   
60.
Context: Aceclofenac is an important NSAID; however, it causes GI disturbances whereas employing transdermal route would require permeation enhancer for systemic application, thereby causing skin damage. Ceramide 2 is a natural lipid having an important role in the maintenance of skin. Objective: Aceclofenac-loaded nanovesicles of ceramide-2, cholesterol, palmitic acid, and cholesteryl sulfate were formulated and analyzed for physical and biological properties. Materials and method: Film hydration method was used to prepare the vesicles and physical parameters, in vitro drug release and stability were evaluated. Then, they were formulated into gel and evaluated against a commercial formulation (CF) and gel-containing plain drug (CPG) for ex vivo, in vivo drug permeation, and anti-inflammatory activity. Results: The developed formulations showed best physical profile and ACV-1 gave 92.89% drug release in in vitro studies. Ex vivo studies showed drug permeation between 15.32–31.12?μg/cm2, whereas CPG and CF released 0.47 and 2.81?μg/cm2, respectively. ACVG-1 and CF showed Cmax of 8.1 and 1.2?μg/ml at 8 and 4?h, respectively. ACVG-1 showed 11.6 times AUC than CF. ACVG-1 inhibited edema by 44% in first hour itself. Discussion: Ceramide 2 and palmitic acid played an important role in the formulation and promotes the drug permeation through stratum corneum and dermis. Ceramide content of the formulation also contributes towards stability and skin protection. Conclusion: The composition of the vesicle formulation performs an important role in physical properties and drug permeation, thereby producing an optimum formulation.  相似文献   
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