Temporary antibiotic-loaded cemented prosthesis for two-stage septic hip arthroplasty

BACKGROUND AND OBJECTIVES: Myofascial pain is the leading cause of chronic low back pain and in most cases can be successfully resolved with trigger point injections of local anesthetics. This type of pain can exist during pregnancy and exceed the analgesia provided by an epidural for labor. METHODS: A 31-year-old primiparous woman received an epidural infusion for labor analgesia. Despite complete resolution of labor pain and a solid, bilateral T10 block, the patient reported discomfort at two discrete locations in her right lumbar paraspinous muscle. RESULTS: The administration of local anesthetic via trigger point injections resulted in successful palliation of the myofascial pain. CONCLUSIONS: Myofascial pain can be an etiology of back pain in the parturient. Trigger point injections, even when used concomitantly with a functioning epidural infusion, can be a valuable aid for the provision of complete analgesia.     

Stability of ruthenium catalysts supported on TiO2 or ZrO2 in catalytic wet air oxidation

The stability of ruthenium catalysts supported on TiO₂ and ZrO₂ were studied in the wet air oxidation of aqueous solution of succinic and p-hydroxybenzoic acids taken as model effluent and on real effluents from the paper-pulp industry. Catalyst recycling experiments were conducted in batch reactor and long-term stability tests were conducted in trickle-bed reactor. In all experiments, ruthenium and support materials were perfectly stable to leaching, sintering and fouling. Ruthenium catalysts experienced a weak deactivation as they were exposed to air, e.g., in recycling experiments however the loss of activity occurred only after the first exposure and was completely reversible upon catalyst reduction. The deactivation was attributed to an over-oxidation of the catalyst surface particularly noticeable in the case of very small Ru-clusters (1 nm).     

Aerobic selective oxidation of (hetero)aromatic primary alcohols to aldehydes or carboxylic acids over carbon supported platinum

The synthesis of substituted benzaldehydes, benzoic acids, heterocyclic aromatic aldehydes and acids has been studied via the oxidation of the aromatic alcohols with air under mild pressure (<20 bar) at 100 °C, in the presence of a 1.95 wt.% Pt/C catalyst. The solvent was found to play the most important role in determining the selectivity of the oxidation products. Changing the solvent enabled tuning the reaction either to the aldehyde (pure dioxane), or the carboxylic acid (dioxane/aqueous solution without or with addition of sodium hydroxide). This oxidation method allowed to effectively oxidize many substituted benzylalcohols with various electron-releasing or -attracting groups (NO₂, Me, OMe, Cl, Br, OH, phenyl, …) and heterocyclic alcohols including nitrogen and sulphur atoms (2-thiophenemethanol, 2- and 4-pyridine methanol compounds).     

Hydrodynamique des contacteurs gaz—Liquide du type venturi à émulsion fonctionnant en autoaspiration

The gas–liquid contactors of the emulsion venturi type can be used as a transfer element for oxygen in a bioreactor. For a self-aspiration operation of the system, the extrapolation requires that the self-aspired gas flowrate is known as a function of some geometric and operational parameters. From hydrodynamical measuremnts made on three Venturis of various nozzle diameters, an experimental method of extrapolation is proposed which allows the calculation of the self-aspirate gas flowrate as a function of the recirculated liquid rate, for a venturi of a given geometry.     

Deactivation of metal catalysts in liquid phase organic reactions

The paper gives a general survey of the factors contributing to the deactivation of metal catalysts employed in liquid phase reactions for the synthesis of fine or intermediate chemicals. The main causes of catalyst deactivation are particle sintering, metal and support leaching, deposition of inactive metal layers or polymeric species, and poisoning by strongly adsorbed species. Weakly adsorbed species, poisons at low surface coverage and solvents, may act as selectivity promoters or modifiers. Three examples of long term stability studies carried out in trickle-bed reactor (glucose to sorbitol hydrogenation on Ru/C catalysts, hydroxypropanal to 1,3-propanediol hydrogenation on Ru/TiO₂ catalysts, and wet air oxidation of paper pulp effluents on Ru/TiO₂) are discussed.     

Ductile rupture in thin sheets of two grades of 2024 aluminum alloy

The damage and rupture mechanisms of thin sheets of 2024 aluminum alloy (Al containing Cu, Mn, and Mg elements) are investigated. Two grades are studied: a standard alloy and a high damage tolerance alloy. The microstructure of each material is characterized to obtain the second phase volume content, the dimensions of particles and the initial void volume fraction. The largest particles consist of intermetallics. Mechanical tests are carried out on flat specimens including U-notched (with various notch radii), sharply V-notched and smooth tensile samples. Stable crack growth was studied using “Kahn samples” and pre-cracked large center-cracked tension panels M(T). The macroscopic fracture surface of the different specimens is observed using scanning electron microscopy. Smooth and moderately notched samples exhibit a slant fracture surface, which has an angle of about 45° with respect to the loading direction. With increasing notch severity, the fracture mode changes significantly. Failure initiates at the notch root in a small triangular region perpendicular to the loading direction. Outside this zone, slant fracture is observed. Microscopic observations show two failure micromechanisms. Primary voids are first initiated at intermetallic particles in both cases. In flat regions, i.e. near the notch root of severely notched samples, void growth is promoted and final rupture is caused by “internal necking” between the large cavities. In slanted regions these voids tend to coalesce rapidly according to a “void sheet mechanism” which leads to the formation of smaller secondary voids in the ligaments between the primary voids. These observations can be interpreted using finite element simulations. In particular, it is shown that crack growth occurs under plane strain conditions along the propagation direction.     

Combined efficacy of acamprosate and disulfiram in the treatment of alcoholism: a controlled study

This randomized, double-blind, crossover study in two parts compared tolerability to high doses of formoterol (Oxis Turbuhaler) with that of high doses of terbutaline (Bricanyl Turbuhaler). After Holter monitoring at home, 12 patients were treated with 4+4+4 doses of formoterol Turbuhaler, 6 microg x dose(-1), (total daily metered dose 72 microg) or 4+4+4 doses of terbutaline Turbuhaler, 0.5 mg x dose(-1) (daily dose 6 mg) given in the morning, after lunch and in the evening, for 3 consecutive days. After a one week washout period at home, patients received the alternative treatment. Thereafter, 15 other patients received 8+6+6 doses of formoterol Turbuhaler (total daily metered dose 120 microg) or 8+6+6 doses of terbutaline Turbuhaler (daily dose 10 mg). Pulse, cardiac frequency, blood pressure, serum potassium, electrocardiogram and forced expiratory volume in one second (FEV1) were registered at regular intervals and Holter monitoring was applied during all 4 treatment days. Terbutaline 6 mg showed significantly greater systemic effects than formoterol 72 microg on pulse, blood pressure, cardiac frequency and QTc (QT interval corrected for heart rate). Terbutaline 10 mg had significantly greater effects than formoterol 120 microg on serum potassium levels, pulse, cardiac frequency and QTc. No differences in FEV1 levels were found. Both drugs were safe and generally well tolerated on both dose levels. In conclusion, high doses of formoterol Turbuhaler over 3 days were generally safe and well tolerated. Daily doses of 6 mg and 10 mg terbutaline Turbuhaler were systemically more potent than 72 microg and 120 microg formoterol, respectively. The safety margin thus appears to be wide if patients happen to use extra doses of formoterol in addition to those prescribed for regular use.     

Diastereoselective Heterogeneous Catalytic Hydrogenation of Aromatic or Heteraromatic Compounds

The diastereoselective hydrogenation catalyzed by heterogeneous metallic catalysts uses a covalently bound chiral auxiliary to induce the chirality. It remains an active synthetic methodology in the asymmetric synthesis of chiral products and may proceed with high diastereoselectivity. This review describes recent examples using this method, such as hydrogenation of C=C, C=O, and C=N bonds. The use of a chiral auxiliary group has also been successfully applied to the hydrogenation of aromatic and heteroaromatic rings. The choice of the chiral auxiliary was found to play a key role in the asymmetric hydrogenation. The results could be explained in terms of steric effect, with a preferred conformation of the adduct substrate and the addition occurring from the less bulky side. The catalytic metal, the support and the presence of additives were also found to have a significant influence.