Is intra-articular pethidine an alternative to local anaesthetics in arthroscopy? A double-blind study comparing prilocaine with pethidine

We investigated the per- and postoperative pain-reducing effect of pethidine given intra-articularly (i. art.). Thirty patients subjected to knee joint arthroscopy, diagnostic and surgical procedures, were randomly assigned to one of three groups. Group A consisted of ten patients who received 250 mg prilocaine + 200 micrograms adrenaline (i. art.) in a volume of 50 ml, group B of ten patients who received 200 mg pethidine (i. art.) in 50 ml saline, and group C of ten patients who received 200 mg pethidine + 200 micrograms adrenaline (i. art.) in 50 ml saline. During arthroscopy the patients reported on pain intensity and discomfort using visual analogue scales. Ratings were low and did not differ significantly between the three groups. Two of three patients in each group requested additional analgesics or sedatives due to pain and discomfort, but again with no difference between the three groups. Postoperatively all patients rated their pain intensity at rest and during movement (at 0, 1, 2, 3, 4, 5, 6, 12 and 24 h). The patients receiving pethidine (group B) reported significantly less pain at rest and movement than group A patients, in general at 1-4 h postoperatively. A significant difference was detected between groups B and C at 4 h postoperatively. Calculating the total sum of pain scores, patients receiving pethidine (group B) reported significantly less pain both at rest and during movement than those receiving prilocaine (group A). Furthermore, patients in group B used significantly less analgesics than those in group A. Adrenaline did not potentiate the effect of pethidine.(ABSTRACT TRUNCATED AT 250 WORDS)     

Operational support systems for the future

The information services market, emerging from the convergence of telecommunications, information technology, entertainment and other industries, poses serious challenges for operational support systems. Historical ways of understanding and delivering operational support functions will no longer work. Business management functions will increasingly be a major commercial differentiator in the new market. This paper argues that these functions need to be re-defined as business services so that a market can develop in them. It explains a technical approach to defining and building these business services, which is being researched at BT Laboratories, and which uses configurable business objects and intelligent agents. This approach offers the possibility of managing the complexity that the explosion of new information services will bring, and also of opening up exciting new business possibilities.     

Studies on the safety of glucose and paraben-containing neostigmine for intrathecal administration

Oxysterols are biologically active molecules generated during oxidation of LDL. Several of these oxysterols were found in macrophage-derived foam cells from human atherosclerotic tissue (eg, 7-hydroxycholesterol, 7-ketocholesterol, 5-epoxycholesterol, and 25-hydroxycholesterol). A specific stimulation of interleukin-8 (IL-8) production by oxidized LDL (oxLDL) has been shown by other investigators. In foam cells from human atherosclerotic tissue, we found high levels of IL-8 (183.1 pg/10(6) cells) compared with monocytes (23.2 pg/10(6) cells) or monocyte-derived macrophages in culture (1.5 pg/10(6) cells). When monocytes and monocyte-derived macrophages, in vitro, were exposed to a series of different oxysterols, we found that all oxysterols tested had a tendency to stimulate IL-8 production but that 25-hydroxycholesterol was the most potent one. This stimulation of IL-8 production was time and dose dependent and could be blocked by cycloheximide. These results indicate that oxysterols in oxLDL may have a regulatory effect on IL-8 production. IL-8, a potent chemoattractant, may play a role in the recruitment of T lymphocytes and smooth muscle cells into the subendothelial space and may contribute to the formation of atherosclerotic lesions.     

Structural studies of the cell envelope lipopolysaccharides from Haemophilus ducreyi strains ITM 2665 and ITM 4747

The structures of the lipopolysaccharides from Haemophilus ducreyi strains ITM 2665 and ITM 4747 have been investigated. Oligosaccharides were obtained from phenol/water-extracted lipopolysaccharide by mild acid hydrolysis and were studied with methylation analysis, fast atom bombardment-mass spectrometry, and NMR spectroscopy. The major oligosaccharide obtained from strain 2665 is a nonasaccharide with the following structure: beta-D-Galp-1-->4-beta-D-GlcNAcp-1-->3-beta-D-Galp-1-->4-D-alpha-D -Hepp- 1-->6-beta-D-Glcp-1-->(L-alpha-D-Hepp-1-->2-L-alpha-D-Hepp-1 -->3)-4-L-alpha- D-Hepp-Kdo, where the reducing terminal 3-deoxy-D-manno-octulosonic acid (or Kdo) exists in reduced anhydro forms. The proposed structure complements the preliminary structure described for Haemophilus ducreyi strain 35000 (Melaugh, W., Phillips, N. J., Campagnari, A. A., Karalus, R., and Gibson, B. W. (1992) J. Biol. Chem. 267, 13434-13439) with the missing anomeric configurations. The saccharide isolated from strain 4747 is a markedly simpler hexasaccharide with the following structure: beta-D-Galp-1-->4-beta-D-Glcp-1-->(L-alpha-D-Hepp-1-->2-L-alpha-D- Hepp- 1-->3)4-L-alpha-D-Hepp-Kdo. Apart from a different phosphorylation of the inner core region the proposed structure is identical to the structure of lipopolysaccharide from an only distantly related bacterium, viz. Haemophilus influenzae nontypable strain 2019 (Phillips, N. J., Apicella, M. A., Griffiss, J. M., and Gibson, B.W. (1992) Biochemistry 31, 4515-4526). The implications of these findings as regards the role of lipopolysaccharide as a virulence factor are discussed.     

A note on metric dimension and feedback in discrete time

The notions of a ∈-dimension and ∈-entropy were introduced into feedback theory of G. Zames (1976, 1979), who proposed them as measures of the complexity of identification and the effectiveness of feedback in reducing identification costs. The 1979 paper was concerned mainly with continuous-time systems, but also included a summary of discrete-time results which contained certain errata. The authors elaborate the discrete-time case, supply some omitted proofs, and correct the errata     

Attention deficit disorder and neuropsychological functioning in children with Tourette's syndrome.

Neuropsychological deficits in Tourette's syndrome (TS) may result from comorbid psychiatric disorders. This study compared the neuropsychological performance of TS children with and without attention deficit disorder (ADD). Participants were 82 children between 6 and 18 yrs of age with TS, 36 of whom had ADD. ADD children did not differ from non-ADD children in age or in onset or duration of TS but did display more severe complex tics and obsessive-compulsive symptoms. After statistical control for these characteristics, ADD children demonstrated significant deficits in various elements of attention, including encoding, sustaining, and focusing/ executing, and in academic achievement. They did not differ in IQ, non-attentional cognitive skills, or sensorimotor functions. The comorbid psychiatric disorders associated with TS yield distinct patterns of neuropsychological functioning that may reflect overlapping neuroanatomic substrates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Low-power chip-to-chip communication circuits

Low-power chip-to-chip communication circuits for CMOS digital chips using the current-mode approach are presented. The circuits are based on the use of current direction to represent the logic values and stabilisation of the potential of communicating pads. Measurement results reveal that a power saving of 40 times is achievable     

Substance use risk across three generations: The roles of parent discipline practices and inhibitory control.

This study used 3 generations and 21 years of prospective data to test models of intergenerational transmission of substance use and substance use risk. Thus, the study extends prior studies in the field that have focused predominantly on substance abuse. The association between the grandparental generation's (G1 mother and father) and the parental generation's (G2 father) alcohol use and illicit drug use was hypothesized to be mediated by G2's poor inhibitory control. Additionally, G1's poor discipline of G2 was hypothesized to be directly associated with G2's substance use as well as to partially mediate the association between G1's substance use and G2's inhibitory control. In turn, G2's substance use in late adolescence was expected to be associated with its offspring's (G3) poor inhibitory control at age 3 years. Findings partially supported the predictions and varied by substance. For alcohol use, only cross-generational associations in use were found. For illicit drugs, both poor inhibitory control and poor discipline played some mediational role in cross-generational use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Markov-based eigenanalysis method for frequency estimation

This paper proposes an eigenanalysis-based method for estimating the frequencies of complex-valued sine waves. The basic idea behind this method consists of using a set of linearly independent vectors that are orthogonal to the signal subspace spanned by the principal eigenvectors of the data covariance matrix. Exploiting that orthogonality condition gives an overdetermined system of linear equations, the unknown parameters of which are uniquely related to the frequencies. Analytical expressions are derived for the covariances of the equation errors in the sample version of the aforementioned linear system of equations. Based on these expressions a Markov-like estimate of the unknown parameters is introduced, which asymptotically (with respect to either the number of data samples or the signal-to-noise ratio) provides the minimum variance frequency estimates in a fairly large class of consistent estimators. The paper includes Monte-Carlo simulations that support the theoretical analysis results and show that those results may apply to scenarios with rather low values of the number of data samples and the signal-to-noise ratio