Quantum-chemical simulation of the adsorption-induced reduction of strength of siloxane bonds.

Mechanical strength of silicate glasses is known to decrease markedly due to the adsorption of molecules from the environment, especially in aqueous alkali solutions. This effect, known as the adsorption-induced reduction of strength (AIRS), has not yet been fully understood. Here, the dependence on the chemical nature and electronic properties of adsorbates of the AIRS of siloxane bonds in silica was studied by means of quantum-chemical calculations at the wB97X-D3/def2-TZVP level of theory.

Meningitis after percutaneous radiofrequency trigeminal ganglion lesion. Case report and review of literature.

Case Report: A 79-year-old man with severe trigeminal neuralgia presented to the pain clinic, and was offered a radiofrequency trigeminal ganglion lesion. He had only partial response to the first procedure, so a second was undertaken. The following day he presented with signs of meningitis and the diagnosis was confirmed on lumbar puncture.

Temperature and pressure dependences of tunneling rate constant: density-functional theory potential-energy surface for H-atom transfer in the fluorene-acridine system.

Temperature and pressure dependences of rate constants for solid phase tunneling reactions are analytically considered within the framework of modified theory of radiationless transitions, taking into account the intermolecular and soft intramolecular promotive vibrations of reagents. This treatment allows us to describe theoretically the process of atomic tunneling and the effect of temperature on the potential barrier and reorganization of the reagents. The influence of external pressure appears in our treatment as a static reduction of widths and heights of the potential barrier with hydrostatic compression of the matrix, and also as an increase of frequencies of promotive vibrational modes owing to anharmonicity.

Tolerability of acute postoperative pain management: nausea, vomiting, sedation, pruritus, and urinary retention. Evidence from published data.

This review examines the evidence from published data concerning the tolerability (indicated by the incidence of nausea, vomiting, sedation, pruritus, and urinary retention), of three analgesic techniques after major surgery; intramuscular analgesia (i.m.), patient-controlled analgesia (PCA), and epidural analgesia.

Pre-operative and post-operative effect of a pain management programme prior to total hip replacement: a randomized controlled trial.

Patients may wait some time for total hip replacement with conservative management of pain and disability, but no attempts to rehabilitate them. This study randomised 40 patients accepted for and awaiting total hip replacement to a brief rehabilitative psychologically based pain management programme (PMP) or to a control group with no intervention. Patients were assessed before randomisation, 3 months after the PMP or equivalent waiting time, and again one year later after total hip replacement.

Respiratory and haemodynamic effects of acute postoperative pain management: evidence from published data.

Background: This study examines the evidence from published data concerning the adverse respiratory and haemodynamic effects of three analgesic techniques after major surgery; i.m. analgesia, patient-controlled analgesia (PCA), and epidural analgesia.

Factors affecting medical decision-making in patients with osteoarthritis of the hip: allocation of surgical priority.

Purpose: The purpose was to determine (1) how well doctors' assessments of patients matched the patients'own self assessments and (2) what doctors looked for in terms of patient factors (such as pain and dysfunction, radiographic evidence) that influenced their decisions to allocate priority for hip replacement.

Method: Data collected independently from patients and surgeons after consultation were used to investigate medical decision-making. Patients were 74 consecutive patients who were offered total hip replacement in an orthopaedic outpatient department at a single hospital.

A pilot study of the effect of the Queen's Square external bladder stimulator on urinary retention after knee replacement surgery.

Postoperative urinary retention remains an important problem after major orthopaedic surgery and can increase morbidity. External vibration applied to the suprapubic region has improved bladder emptying and urinary symptoms in patients with neurogenic bladders. Forty-three patients undergoing elective major knee surgery were randomly assigned to receive either a Queen's Square bladder stimulator or placebo device for 24 h postoperatively.

Effectiveness of acute postoperative pain management: I. Evidence from published data.

Background: This review examines the evidence from published data concerning the incidence of moderate-severe and of severe pain after major surgery, with three analgesic techniques; intramuscular (i.m.) analgesia, patient controlled analgesia (PCA), and epidural analgesia.

Presacral neurolytic block for relief of pain from pelvic cancer: description and use of a CT-guided lateral approach.

A CT guided lateral approach for neurolysis of the presacral plexus is described for treatment of pelvic pain due to advanced cancer. The technique was evaluated in two patients with unrelieved pelvic and perineal pain. Other neurolytic techniques used to treat pelvic pain due to advanced cancer are reviewed with a discussion of benefits and potential side effects of this technique.

Coeliac plexus block using computed tomography guidance.

Coeliac plexus blocks have been used successfully in the treatment of abdominal pain in advanced cancer and in benign chronic abdominal pain. However, concern remains about occasional potentially serious complications. One possible way to reduce the risks of this procedure may be to improve imaging during the procedure.

The use of interpleural analgesia using bupivacaine for pain relief in advanced cancer.

The use of interpleural analgesia is described in six patients with a variety of advanced malignancies suffering from pain uncontrolled by opioids. The benefits and complications of the technique are discussed including management of the catheters at home and the measurement of plasma bupivacaine concentrations. Interpleural analgesia can provide good analgesia in a small, selected population of patients with otherwise uncontrolled pain of malignant origin.

Rehabilitation of chronic low back pain using continuous epidural analgesia.

Purpose: Physical rehabilitation is one of the major forms of treatment of chronic low back pain. The ability of some patients to cooperate is limited by pain. Since 1992 continuous epidural analgesia has been combined with a physical rehabilitation programme for patients with chronic low back pain who have been unable to make progress with conventional physical rehabilitation due to severity of pain.

Calcium channel antagonists prevent adaptive responses to ethanol.

Prolonged ethanol administration causes upregulation of dihydropyridine-sensitive binding sites, thought to represent neuronal calcium channels, and these channels appear to play an important role in ethanol physical dependence. Dihydropyridine calcium channel antagonists, when given chronically with ethanol, prevent the development of tolerance to ethanol and the ethanol withdrawal syndrome. The upregulation of binding sites for these compounds was also prevented.

Alkaline chemical keratitis: eye injury from airbags.

Inflation of an automobile airbag is accomplished by converting sodium azide to nitrogen gas. The bags are vented so that nitrogen and residual byproducts of combustion, such as alkaline gas, are released into the passenger compartment. We report the case of a patient who incurred a chemical keratitis after the driver's-side airbag deployed.

Does glycine antagonism underlie the excitatory effects of methohexitone and propofol?

We have investigated the pharmacological basis of CNS excitation that occurs in association with general anaesthesia in mice. Propofol produced sustained clonic movements during anaesthesia. Methohexitone produced intermittent non-rhythmic jerking during anaesthesia.

The effects of chronic treatment with the dihydropyridine, Bay K 8644, on hyperexcitability due to ethanol withdrawal, in vivo and in vitro.

1. The effects of chronic treatment with the dihydropyridine, Bay K 8644, were studied on the ethanol withdrawal syndrome, in vivo and in vitro. 2.

Chronic dihydropyridine treatment can reverse the behavioural consequences of and prevent adaptations to, chronic ethanol treatment.

1. Chronic treatment with the dihydropyridine calcium channel antagonist, nitrendipine, given concurrently with ethanol, prevented the ethanol withdrawal syndrome in mice, even though the chronic nitrendipine treatment was stopped 24 h or 48 h before the withdrawal testing. 2.

Differential interactions between benzodiazepines and the dihydropyridines, nitrendipine and Bay K 8644.

The effects of the dihydropyridine calcium antagonist, nitrendipine and the calcium channel activator, Bay K 8644, have been compared on the anaesthetic, ataxic and anticonvulsant effects of benzodiazepines. Possible interactions between the peripheral benzodiazepine receptor antagonist, PK11195, and the classical benzodiazepines were also examined. Nitrendipine considerably potentiated the anaesthetic effects of benzodiazepines and increased their ataxic effects but had no effect on the anticonvulsant actions.

Nitrendipine decreases benzodiazepine withdrawal seizures but not the development of benzodiazepine tolerance or withdrawal signs.

1. The effects of the calcium channel blocking agent, nitrendipine, were studied on seizures in mice produced during withdrawal from chronic benzodiazepine treatment and on the development of tolerance to benzodiazepines. 2.

Effects of N-methyl-D-aspartate on [Ca2+]i and the energy state in the brain by 19F- and 31P-nuclear magnetic resonance spectroscopy.

The effects of N-methyl-D-aspartate (NMDA) on the free intracellular Ca2+ concentration [( Ca2+]i) and the energy state in superfused cerebral cortical slices have been studied using 19F- and 31P-nuclear magnetic resonance spectroscopy. [Ca2+]i was measured using the calcium indicator 1,2-bis(2-amino-5-fluorophenoxy)ethane-N,N,N',N'-tetraacetic acid (5FBAPTA). NMDA (10 microM) in the absence of extracellular Mg2+ caused the expected rise in [Ca2+]i but produced an impairment of the energy state: the phosphocreatine (PCr) content was decreased by 42%, and the Pi/PCr ratio was increased by 55%.

Use of 1,2-bis(2-amino-5-fluorophenoxy)ethane-N,N,N',N'-tetraacetic acid (5FBAPTA) in the measurement of free intracellular calcium in the brain by 19F-nuclear magnetic resonance spectroscopy.

We have applied the 19F-nuclear magnetic resonance (NMR) calcium indicator 1,2-bis(2-amino-5-fluoro-phenoxy)ethane-N,N,N',N'-tetraacetic acid (5FBAPTA) to the measurement of the free intracellular calcium concentration [( Ca2+]i) in superfused brain slices. A mean +/- SD control value of 380 +/- 71 nM (n = 18) was obtained at 37 degrees C using 2.4 mM extracellular Ca2+.

Are changes in neuronal calcium channels involved in ethanol tolerance?

Effects on the development of tolerance to ethanol of concurrent administration of the dihydropyridine calcium channel antagonist, nitrendipine, were investigated. Ethanol tolerance was induced in rats by repeated i.p.