Formation and enhanced biocidal activity of water-dispersable organic nanoparticles.

Water-insoluble organic compounds are often used in aqueous environments in various pharmaceutical and consumer products. To overcome insolubility, the particles are dispersed in a medium during product formation, but large particles that are formed may affect product performance and safety. Many techniques have been used to produce nanodispersions-dispersions with nanometre-scale dimensions-that have properties similar to solutions.

Selective one-pot synthesis of trithiocarbonates, xanthates, and dithiocarbamates for use in RAFT/MADIX living radical polymerizations.

[reaction: see text] We report a facile route for the production of chain transfer agents for reversible addition fragmentation chain transfer (RAFT) and macromolecular design via the interchange of xanthates (MADIX) polymerizations, via a one-pot reaction. 1,1'-Thiocarbonyl diimidazole (TCDI) undergoes controlled monosubstitution when reacted with secondary thiols or alcohols. The intermediate S/O-esters of imidazole-N-thionocarboxylic acid react efficiently with a range of primary thiols, alcohols, and amines to form asymmetrical dithiocarbonates, trithiocarbonates, and dithiocarbamates, respectively.

A multicenter evaluation of total intravenous anesthesia with remifentanil and propofol for elective inpatient surgery.

Remifentanil is a mu-opioid receptor agonist with a context sensitive half-time of 3 min and an elimination half-life < or = 10 min. This study sought to evaluate the efficacy of remifentanil and propofol total intravenous anesthesia (TIVA) in 161 patients undergoing inpatient surgery. Remifentanil 1 microgram/kg was given intravenously (i.

A double-blind, placebo-controlled pilot study examining the effectiveness of intravenous ondansetron in the prevention of postoperative nausea and emesis.

Study Objective: To compare the efficacy and safety profiles of ondansetron and a placebo when infused immediately prior to anesthesia induction for the prevention of postoperative nausea and emesis (vomiting or retching).

Design: Randomized, double-blind, placebo-controlled, parallel, multicenter pilot study.

Setting: Three U.

Comparison of ondansetron versus placebo to prevent postoperative nausea and vomiting in women undergoing ambulatory gynecologic surgery.

Background: Postoperative nausea and emesis, especially in ambulatory surgical patients, remains a troublesome problem. This study was performed to compare the incidence of nausea and emesis during the 24-h postoperative period in ondansetron-treated patients versus placebo-treated patients.

Methods: Using a randomized prospective double-blind study design, women between the ages of 18 and 70 yr undergoing gynecologic surgical procedures with general opioid anesthesia on an outpatient basis were enrolled.

Prophylactic intravenous ondansetron in female outpatients undergoing gynaecological surgery: a multicentre dose-comparison study.

The efficacy and safety of prophylactic intravenous ondansetron in preventing postoperative nausea and vomiting was investigated in a randomized, stratified, double-blind, placebo-controlled, dose-comparison study of 580 ASA physical class I and II female outpatients undergoing gynaecological surgery and receiving general anaesthesia. Patients received either ondansetron 1, 4 or 8 mg, or placebo i.v.

Neuromuscular and cardiovascular effects of pipecuronium.

Pipecuronium bromide (Arduan) is a bisquaternary, steroid-type neuromuscular blocking agent in clinical use in Eastern Europe. Before its introduction into clinical practice in the USA, in the first phase of this study the neuromuscular potency of pipecuronium was determined under "balanced" and enflurance anaesthesia by the cumulative log dose-response method in 30 patients each. In the second phase the intubation and onset times, clinical duration of the first and repeated doses, spontaneous recovery index, reversibility of its residual neuromuscular effect by an anticholinesterase and its effect on heart rate and blood pressure was compared with the same variables observed in patients, anaesthetized with identical techniques but who had received vecuronium or pancuronium.

In vitro comparison of the neuromuscular antinicotinic and intestinal antimuscarinic effects of different nondepolarizing muscle relaxants.

The postsynaptic antimuscarinic properties of different nondepolarizing muscle relaxants were compared with their postsynaptic antinicotinic effect. d-Tubocurarine, pipecuronium and vecuronium were the most selective antagonists on postsynaptic nicotinic receptors. Gallamine, diadonium and Duador (RGH-4201) had relatively greater effect on postsynaptic muscarinic receptors.

Presynaptic effect of muscle relaxants on the release of 3H-norepinephrine controlled by endogenous acetylcholine in guinea pig atrium.

The influence of nondepolarizing muscle relaxants (MR) on the resting and electrically evoked release of tritiated norepinephrine (3H-NE) was investigated, in the absence and presence of 10(-4) mol/l cocaine, in the in vitro right atrium preparation of guinea pigs (g.p.) preloaded with 3H-NE.

A simple method for monitoring muscular relaxation during continuous infusion of vecuronium.

There is considerable individual variation in the dose of vecuronium required for the maintenance of surgical relaxation. Therefore to provide uninterrupted relaxation without overdosage it is advisable to regulate the IV infusion of vecuronium on the basis of appropriate monitoring. Monitoring with mechanomyography (MMG) or electromyography requires costly equipment and is too complex for routine clinical use.

Modulation of stimulation-evoked release of newly formed acetylcholine from mouse hemidiaphragm preparation.

A radioisotope method has been developed for measuring the stimulation-evoked release of acetylcholine without the use of cholinesterase inhibitors from the mouse hemidiaphragm preparation which had been loaded with 3H-choline. Evidence has been obtained that 3H-choline was taken up by and released from both innervated and non-innervated mouse hemidiaphragm preparations. However, it was released in the form of 3H-acetylcholine in response to electrical field stimulation only from the innervated preparations.

Effect of mono- and diaminopyridines on release of [3H]norepinephrine from isolated guinea-pig atrium.

Neurochemical evidence has been obtained that 4-aminopyridine, 3,4-diaminopyridine and 3,3-dimethyl-1-(4-amino-3-pyridyl)urea HBr (LF-14), concentration-dependently enhanced the stimulation-evoked release of [3H]norepinephrine ([3H]NE) from isolated guinea-pig atrium. The effects of aminopyridines, compounds known to inhibit potassium channels, were Ca0-dependent. High pressure liquid chromatography, combined with radiochemical detection, indicated that the increased stimulated release of radioactivity was due to [3H]NE.

Tubocurarine and pancuronium inhibit evoked release of acetylcholine from the mouse hemidiaphragm preparation.

Using a sensitive radioactive method that measures selectively the evoked release of acetylcholine, it was demonstrated that, when stimulating at 50 Hz, tubocurarine or pancuronium 2 X 10(-5) mol litre-1 or hexamethonium 10(-3) mol litre-1 significantly decreased the evoked release of acetylcholine in the mouse in vitro phrenic nerve-hemidiaphragm preparation.

Direct evidence that pancuronium and gallamine enhance the release of norepinephrine from the atrial sympathetic nerve by inhibiting prejunctional muscarinic receptors.

The effect of different non-depolarizing muscle relaxants (gallamine, pancuronium, vecuronium, D-tubocurarine) on [3H]norepinephrine release in response to electrical stimulation was studied in isolated guinea-pig atrium. High pressure liquid chromatography combined with electrochemical and radiochemical detection revealed that the released radioactivity was mainly in the form of [3H]norepinephrine release. Oxotremorine, a pure muscarinic agonist, reduced the release of tritium.

Electrochemical determination of histamine derivatized with o-phthalaldehyde and 2-mercaptoethanol.

High-performance liquid chromatography coupled with electrochemical detection was used to determine histamine following precolumn derivatization with o-phthalaldehyde (OPA) and 2-mercaptoethanol. The isoindole derivative which is obtained as reaction product was electrochemically active at a moderate potential (peak potential +0.4 V).

Determination of histamine concentrations in plasma by liquid chromatography/electrochemistry.

Histamine was extracted from deproteinized plasma with Amberlite CG 50 weak cation-exchange resin (analytical recovery of [3H]histamine, 60.5%). The eluate was evaporated and histamine in the redissolved sample was condensed with o-phthalaldehyde and 2-mercaptoethanol at pH 11.

A simple and sensitive method of acetylcholine identification and assay. Bioassay combined with minicolumn gel filtration or high-performance liquid chromatography.

A modified technique of acetylcholine assay on the guinea pig ileum has been combined with either minivolume gel filtration or high-performance liquid chromatography separation of the samples. In addition, labeled acetylcholine (14C-ACh) was eluted with unlabeled acetylcholine or with the samples expected to contain acetylcholine, and their elution profiles were compared by bioassay plus radioassay of eluate fractions. When the elution of both biological activity and label occurred in the same eluates, it was concluded that the substance assayed on guinea pig ileum was acetylcholine.

Treatment of backache with spinal injections of local anesthetics, spinal and systemic steroids. A review.

Low back pain and sciatica have been treated with peridural local anesthetics for over 80 years and with epidural and subarachnoid steroid injections for a quarter of a century. This review surveyed the literature concerning the evolution, pathophysiology, complications and results of this type of therapy. The volume injected and the method used vary with different physicians and no standard has been established.

Presynaptic inhibitory effect of Met-enkephalin on [14C] acetylcholine release from the myenteric plexus and its interaction with muscarinic negative feedback inhibition.

The effect of Met-enkephalin on the release of radioactivity (14C) from a myenteric plexus-longitudinal muscle preparation loaded with [14C]choline has been investigated under different conditions, when the muscarinic receptor mediated negative feedback inhibition was operative or when it was completely excluded by atropine. Separation of the [14C]acetylcholine (ACh) and [14C] choline components of the released radioactivity revealed that during 45-min incubation periods about 3.2% of the ACh store became labeled and that during stimulation only the release of [14C]ACh increased above resting level.

Common bile duct pressure changes after fentanyl, morphine, meperidine, butorphanol, and naloxone.

Five groups of 10 patients received thiamylal, enflurane, nitrous oxide-oxygen anesthesia for elective cholecystectomy. The common bile duct was intubated via the cystic duct with a 16-g plastic catheter, and the control intraductal pressure was measured. Patients then were given equi-analgesic doses of fentanyl, morphine, meperidine, butorphanol, or placebo intravenously, and the common bile duct pressure was recorded for 20 min.

Prevention of succinylcholine induced hyperkalemia by neurolept anesthesia and hexafluorenium in anephric patients.

Forty patients, half of them with normal kidney function, the other half anephric were included in the study. All received diphenhydramine, meperidine and atropine for premedication and droperidol, fentanyl, N2O and O2 for anesthesia. For endotracheal intubation and further relaxation 0.