ABSTRACT
Various methods for the treatment of trigger digits exist. This study was designed to compare the results of an open surgical technique with those of a percutaneous surgical technique for the treatment of trigger digits. Ninety-six patients with 100 trigger digits were randomized to either open (n = 46) or percutaneous (n = 54) surgical release of the first annular pulley. Operation time, duration of postoperative pain, recovery of motor function, and surgical complications were assessed. Trigger digits were successfully treated in 98% of the cases using the open surgical technique and in 100% of the cases using the percutaneous technique. Mean operation time was significantly longer using the open technique. Mean duration of postoperative pain and time to recovery of motor function were significantly shorter for patients treated with the percutaneous method. No serious complications were observed in either group. We conclude that percutaneous correction of trigger digits is a quicker procedure, is less painful, and shows significantly better results in rehabilitation than open surgery.
Subject(s)
Orthopedic Procedures , Tenosynovitis/surgery , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Pain, Postoperative , Prospective StudiesABSTRACT
PURPOSE: To determine the cloud point of a variety of nonionic surfactants and to search for means to raise the surfactant cloud point in liquid formulations. METHODS: Cloud points of nonionic surfactants were determined visually in a water bath. Organic compounds, many of which have been used as pharmaceutical excipients, were tested initially for effect on the cloud point of poloxamine 908. Four effective cloud point boosters (CPBs) from different structural classes were further tested on additional surfactants. RESULTS: A number of compounds can raise the cloud point of nonionic surfactants. These cloud point boosters are classified into two categories: nonionic and ionic. The nonionic CPBs include poly(ethylene glycols), propylene glycol, methanol, ethanol, isopropanol, and 2-hydroxypropyl-beta-cyclodextrin. They are effective at molar concentrations. The ionic CPBs include anionic and cationic surfactants, charged phospholipids, long chain fatty acids, and bile salts. They are effective at millimolar concentrations. CONCLUSIONS: The cloud point of nonionic surfactants used in liquid formulations can be modulated through the proper choice of excipient.
Subject(s)
Excipients/chemistry , Surface-Active Agents/chemistry , Alcohols/chemistry , Buffers , Carbohydrates/chemistry , Chromatography, Gel , Chromatography, High Pressure Liquid , Drug Carriers/chemistry , Ethylenediamines/chemistry , Fatty Acids/chemistry , Ionophores/chemistry , Ions , Particle Size , Phospholipids/chemistry , Polyethylene Glycols/chemistry , Solubility , TemperatureABSTRACT
PURPOSE: To study the effects of formulation variables on the physical stability of a submicron crystal (nanocrystal) suspension under steam sterilization conditions. METHODS: Suspensions of ethyl diatrizoate nanocrystals were prepared by wet milling in the presence of the surfactant poloxamine 908. Particle size distribution and zeta potential were measured by photon correlation spectroscopy. RESULTS: On heating, the mean particle size of the nanocrystal suspension remained essentially unchanged up to 110 degrees C, the cloud point of the stabilizing surfactant, but increased significantly above that temperature. The increase in particle size was a result of particle aggregation rather than crystal growth. Adding a cloud point booster to the suspension significantly minimized the particle aggregation at high temperatures. The purity of poloxamine 908 and the tonicity agent and buffer salt used also affected the heat stability of the suspension, the latter agents apparently through altering the surfactant cloud point. CONCLUSIONS: The aggregation of the ethyl diatrizoate nanocrystalline suspension under steam sterilization conditions was a result of phase separation of the stabilizing surfactant at its cloud point. When formulated with a cloud point booster to prevent the phase-separation, the suspension maintained its physical stability under steam sterilization without any significant change in particle size distribution.
Subject(s)
Contrast Media/chemistry , Diatrizoate/analogs & derivatives , Sterilization , Buffers , Crystallization , Diatrizoate/chemistry , Drug Carriers/chemistry , Drug Carriers/isolation & purification , Drug Stability , Ethylenediamines/chemistry , Ethylenediamines/isolation & purification , Hot Temperature , Ionophores/chemistry , Ionophores/isolation & purification , Ions , Polyethylene Glycols/chemistry , Polyethylene Glycols/isolation & purification , Solubility , Sonication , Steam , Surface-Active Agents/chemistry , Surface-Active Agents/isolation & purification , Time FactorsABSTRACT
The effect of racemic mianserin on K+-evoked tritium release from rat brain cortex slices previously incubated with 3H-L-noradrenaline was studied. Racemic mianserin (10(-9)--10(-5) M) increased stimulation-induced release dose-dependently. As methysergide, metiamide, and cyproheptadine failed to do so, it was concluded that this effect was probably not caused by the antihistamine or antiserotonin activity of racemic mianserin, but due to its alpha-adrenolytic effect. Evaluation of the effects of the enantiomers (+)(S)mianserin and (-)(R)mianserin showed that the alpha-adrenolytic effect resided in the (+)isomer, whereas the (-)isomer was inactive at a concentration of 10(-6) M. Inhibition of noradrenaline into rat hypothalamic synaptosomes also showed stereospecificity in that (+)mianserin was about 300-times more active than(-)mianserin. Inhibition of rat muricidal behavior, a test for potential antidepressant activity, showed a similar dissociation in the effects of the two enantiomers, in that (+)mianserin was active, whereas (-)mianserin was not.
