Treatment of pathological humeral shaft fractures with intramedullary nailing. A retrospective study.

A consecutive series of 22 pathological fractures of the humeral shaft in 21 patients treated at one institution were included in this retrospective study. Patients were treated with anterograde locked intramedullary nailing. Mean follow-up was 22.7 months (range 3-60). Mean VAS score improved from 89.5 (range 80-100) to 14.5 (range 0-40). In most patients there was a satisfactory return to daily activities within six weeks of surgery. Seventeen of 19 patients reported to be satisfied. Mean duration of hospitalization after surgery was 4.3 days (range 2-15). There were no complications related to the implants. There were no operative complications and the average operation time was 48 minutes (range 35-160). The consolidation rate was 80%. We emphasize that suspicion of fracture and interdisciplinary work between oncologists and orthopaedic surgeons are of crucial importance for survival time and individual treatment.

Positive-ion ESI mass spectrometry of regioisomeric nonreducing oligosaccharide fatty acid monoesters: in-source fragmentation of sodium adducts.

Structural characterization and differentiation of a novel group of regioisomeric monolaurate esters of the nonreducing trisaccharides raffinose and melezitose, and the nonreducing tetrasaccharide stachyose has been obtained using positive electrospray ionization (ESI) mass spectrometry with in-source fragmentation. The surfactant nature and high polarity of these compounds make them appropriate analytes for being studied by conventional ESI-MS. The position of the acyl chain in each particular regioisomer has been used as a reporter group that allows unambiguous rationalization of the fragmentation routes of the corresponding natriated molecular ions [M + Na](+). In all cases, the main fragment ions were produced through cleavage of the glycosidic bond involving two anomeric carbons, the C-1' and C-2'' of the alpha-D-Glcp-(1-2)-beta-D-Fruf bond, and it was observed that sodium cation retention occurred on the heavier mass fragment of the two formed fragments, (e.g. di- or trisaccharide type vs monosaccharide type). Our results may help to better understand the fragmentation behavior of nonreducing oligosaccharides (as sodium adducts) in positive ESI mass spectrometry.

Determination of regioisomeric distribution in carbohydrate fatty acid monoesters by LC-ESI-MS.

A new LC-ESI-MS method for characterizing the regioisomeric distribution in carbohydrate monoesters with long-chain fatty acids is described. Sucrose monolaurate mixtures were used for development of the method. The surfactant nature and high polarity of these compounds make them appropriate analytes for being detected by electrospray-ionization mass spectrometry (ESI-MS). Despite the structural similarity of regioisomers, an excellent resolution of all regioisomers present in the different samples studied (sucrose monodecanoates, sucrose monolaurates, sucrose monopalmitates and melezitose monolaurates) is achieved. Reversed-phase liquid chromatography with isocratic acetonitrile-water mixtures was used for a proper separation of the analytes. Finally, the superiority of this chromatographic method for determining the regioselectivity in enzymatic carbohydrate acylation reactions, with respect to the typical methodology based on routine 13C NMR spectroscopy, is also discussed.

Total hip arthroplasty in heart transplant patients.

Avascular necrosis of the femoral head (AVNFH) is a known complication after heart transplantation. In order to assess the efficacy and complications of cementless total hip arthroplasty (THA) in this population, the authors analysed 24 cementless THAs in 18 patients with advanced AVNFH (stage II affecting more than 15% of the articular surface, stage III and IV according to the Ficat-Arlet classification) after a heart transplant procedure. Average duration of follow-up was 35.4 months (range: 16 to 66). Pain and function scores (Harris Hip Score and WOMAC arthritis index) showed significant improvement from the preoperative levels. There was no evidence of component loosening, heart-related complications or infection following the THA. Cementless THA is a reasonable treatment option for advanced avascular necrosis of the femoral head following heart transplant procedures.

High-level expression and characterization of Galactomyces geotrichum (BT107) lipase I in Pichia pastoris.

The mature lipI gene, encoding the lipase I from Galactomyces geotrichum BT107, was obtained by PCR from genomic DNA, sequenced and cloned into a Pichia pastoris expression vector. Clones containing multiple copies of lipI integrated in their genome were analyzed to achieve high-level expression of the recombinant lipase I. One strain with four or more copies of the expression cassette was able to produce more than 200mg/L of extracellular heterologous protein. The lipase I was partially purified using anion exchange chromatography and its activity on monounsaturated (triolein) and polyunsaturated (triEPA) triglycerides was analyzed by a novel HPLC-MS assay.

Sensitive gas chromatographic-mass spectrometric method for the determination of phthalate esters, alkylphenols, bisphenol A and their chlorinated derivatives in wastewater samples.

Phthalate esters, alkylphenols, bisphenol A and their chlorinated derivatives are the suspected endocrine disrupters or mutagens. These compounds, commonly called endocrine disrupter chemicals (EDCs), are widely used as plastic additives, lacquers, resins, or surfactants and can be usually found in environmental samples, namely wastewaters. An accurate and reproducible gas chromatographic-mass spectrometric (GC-MS) method is proposed to measure these compounds in wastewater samples of Granada city (Spain). A solid-phase extraction with LiChrolut RP-18 cartridges was carried out and the elution was performed with a diethyl ether/methanol mixture. After isolation, solvent was removed and a silylation step was carried out using N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). Phthalate esters and silylated compounds were identified and quantified by GC-MS using a ZB-5 MS column. Bisphenol F was used as a surrogate. Quantification limits found were between 20 ng L(-1) for 4-nonylphenol and 400 ng L(-1) for benzylbutyl phthalate while inter and intra-day variability was under 5% in all cases. Recoveries for spiked samples were over 95% and under 105%. The method was validated using standard addition calibration and recovery assays.

Gas chromatographic-mass spectrometric method for the determination of bisphenol A and its chlorinated derivatives in urban wastewater.

The simultaneous determination of trace amounts of endocrine disruptors such as bisphenol A (BPA) and its monochloro, dichloro, trichloro and tetrachloro derivatives in wastewater has been developed using gas chromatography-mass spectrometry (GC-MS). Compounds were previously extracted from the aqueous samples using a liquid-liquid extraction procedure with a mixture of dichloromethane:carbon tetrachloride (25/75). After extraction, solvent was removed and a silylation step was carried out with N,O-bis(trimethylsilyl) trifluoroacetamide (BSTFA). The silylated compounds were identified and quantified by GC-MS using an HP1-MS column. The retention times were 6.64 min for BPA silylated, 7.26 min for Cl-BPA silylated, 7.99 min for Cl(2)-BPA silylated, 8.85 min for Cl(3)-BPA silylated and 9.95 min for Cl(4)-BPA silylated. A clean-up is not necessary using SIM mode. Deuterated anthracene (2H(10)-anthracene) was used as an internal standard. The detection limits obtained were 0.3, 0.6, 2.0, 4.5 and 13.0 ng L(-1) for silylated BPA, Cl-BPA, Cl(2)-BPA, Cl(3)-BPA and Cl(4)-BPA, respectively. The proposed method was applied satisfactory to the determination of these chemicals, in different types of wastewater previously spiked with different amounts of these chemicals at concentration levels ranging from 0.01 to 2.50 microg L(-1) for BPA, 0.05-2.50 micro L(-1) for Cl-BPA and 0.05-5.00 microg L(-1) for Cl(2)-BPA, Cl(3)-BPA and Cl(4)-BPA, respectively. The method was validated following standard addition methodology.