[Translated article] Immobilisation with compression bandage vs. antebraquial splint in distal radius fractures operated by open reduction and locking plate. Randomised clinical trial.

INTRODUCTION: Currently, there is a lack of prospective studies to unify criteria about type and time for postoperative immobilisation in surgical distal radius fractures. The aim of this study is to compare functional and radiological results in two groups of distal radius fractures treated with internal fixation with locking plate, and immobilised with antebrachial splint or compression bandage for 3 weeks. MATERIAL AND METHOD: A randomised clinical trial was carried out with two parallel groups with 3, 6, and 12 weeks of follow-up. Main and secondary functional variables were measured, such as pain on VAS scale, values on PRWE, DASH and MRS scale, range of motion in flexion-extension, complications, etc. In addition, some radiological variables were measured at preoperative period and one week after surgery, such as union time, dorsal displacement, shortening, ulnar variance, etc. RESULTS: A total of 62 patients were evaluated: 27 immobilised with bandage and 35 with splint. Analysis of the results obtained showed significant differences in both groups for almost all radiological variables from pre to postoperative period, and for all functional variables from 3 to 12 weeks after surgery. No significant differences were found between the two groups for any of the radiological and functional variables evaluated (VAS 3-12 weeks: p=.584; PWRE 3-12 weeks: p=.248; flexion range of motion 3-12 weeks: p=.959; extension range of motion: p=.50; union time: p=.89). CONCLUSIONS: We do not find clinical or radiological differences between immobilisation with antebrachial splint or compression bandage for distal radius fractures operated with locking plate. A greater number of patients and follow-up are necessary to extrapolate the results to the general population and to establish criteria for good postoperative management of these fractures.

Immobilization with compression bandage vs antebraquial splint in distal radius fractures operated by open reduction and locking plate. Randomized clinical trial. / Inmovilización con vendaje compresivo vs férula antebraquial en fracturas de radio distal intervenidas mediante reducción abierta y placa bloqueada. Ensayo clínico aleatorizado.

INTRODUCTION: Currently, there is a lack of prospective studies to unify criteria about type and time for postoperative immobilization in surgical distal radius fractures. The aim of this study is to compare functional and radiological results in two groups of distal radius fractures treated with internal fixation with locking plate, and immobilized with antebrachial splint or compression bandage for 3weeks. MATERIAL AND METHOD: A randomized clinical trial was carried out with two parallel groups with 3, 6, and 12weeks of follow-up. Main and secondary functional variables were measured, such as pain on VAS scale, values on PRWE, DASH and MRS scale, range of motion in flexion-extension, complications, etc. In addition, some radiological variables were measured at preoperative period and one week after surgery, such as union time, dorsal displacement, shortening, ulnar variance, etc. RESULTS: A total of 62 patients were evaluated: 27 immobilized with bandage and 35 with splint. Analysis of the results obtained showed significant differences in both groups for almost all radiological variables from pre to postoperative period, and for all functional variables from 3 to 12weeks after surgery. No significant differences were found between the two groups for any of the radiological and functional variables evaluated (VAS 3-12weeks: P=.584; PWRE 3-12weeks: P=.248; flexion range of motion 3-12weeks: P=.959; extension range of motion: P=.50; union time: P=.89). CONCLUSIONS: We do not find clinical or radiological differences between immobilization with antebrachial splint or compression bandage for distal radius fractures operated with locking plate. A greater number of patients and follow-up are necessary to extrapolate the results to the general population and to establish criteria for good postoperative management of these fractures.

4D-fingerprints, universal QSAR and QSPR descriptors.

An elusive goal in the field of chemoinformatics and molecular modeling has been the generation of a set of descriptors that, once calculated for a molecule, may be used in a wide variety of applications. Since such universal descriptors are generated free from external constraints, they are inherently independent of the data set in which they are employed. The realization of a set of universal descriptors would significantly streamline such chemoinformatics tasks as virtual high-throughout screening (VHTS) and toxicity profiling. The current study reports the derivation and validation of a potential set of universal descriptors, referred to as the 4D-fingerprints. The 4D-fingerprints are derived from the 4D-molecular similarity analysis. To evaluate the applicability of the 4D-fingerprints as universal descriptors, they are used to generate descriptive QSAR models for 5 independent training sets. Each of the training sets has been analyzed previously by several varying QSAR methods, and the results of the models generated using the 4D-fingerprints are compared to the results of the previous QSAR analyses. It was found that the models generated using the 4D-fingerprints are comparable in quality, based on statistical measures of fit and test set prediction, to the previously reported models for the other QSAR methods. This finding is particularly significant considering the 4D-fingerprints are generated independent of external constraints such as alignment, while the QSAR methods used for comparison all require an alignment analysis.

Binding affinities and geometries of various metal ligands in peptide deformylase inhibitors.

Removal of the N-terminal formyl group from newly synthesized proteins by the enzyme peptide deformylase (PDF) is essential for normal growth of bacteria but not higher organisms. Recently, PDF has been explored as a target for novel antibiotics. Screening a collection of natural products for antimicrobial activity identified actinonin and two matlystatin analogs as potent PDF inhibitors. A number of synthetic analogs of these natural products were prepared and their inhibitory potency determined. Previous work has shown that PDF is an iron metalloproteinase also containing a catalytic glutamic acid residue. Ligation of the ferrous cation is an essential feature of potent inhibitors. The structures of actinonin, a matlystatin analog and a synthetic inhibitor complexed with PDF were determined by crystallography. A quantum mechanics/molecular mechanics (QM/MM) method was used to reproduce the geometry of known complexes, to predict the protonation state in the active site and to predict the geometry of additional complexes. The requirement for protonation of the active site glutamate anion is an important factor in understanding the potency of inhibitors with acidic iron-ligating groups such as hydroxamate and carboxylate. Even though potent inhibitors of PDF have been discovered, their bacteriostatic mechanism of action and the rapid development of resistance in vitro may limit their potential as antibacterial drugs.

Estimation of molecular similarity based on 4D-QSAR analysis: formalism and validation.

The 4D-QSAR paradigm has been used to develop a formalism to estimate molecular similarity measures as a function of conformation, alignment, and atom type. It is possible to estimate the molecular similarity of pairs of molecules based upon the entire ensemble of conformational states each molecule can adopt at a given temperature, normally room temperature. Molecular similarity can be measured in terms of the types of atoms composing each molecule leading to multiple measures of molecular similarity. Multiple measures of molecular similarity can also arise from using different alignment rules to perform relative molecular similarity, RMS, analysis. An alignment independent method of determining molecular similarity measures, referred to as absolute molecular similarity, AMS, analysis has been developed. Various sets and libraries of compounds, including the amino acids, are analyzed using 4D-QSAR molecular similarity analysis to demonstrate the features of the formalism. Exploration of molecular similarity as a function of chirality, identification of common embedded 3D pharmacophores in compounds, and elucidation of 3D-isosteric compounds from structurally diverse libraries are carried out in the application studies.

Extraction of pharmacophore information from high-throughput screens.

Two major advances have been made in the computational perception and utilization of pharmacophores in compound libraries, both real and virtual. Firstly, a hierarchical set of filtering calculations has emerged that can be used to efficiently partition a library into a trial set of pharmacophores. This sequential filtering permits large libraries to be efficiently processed, as well as compounds judged as 'hits' to be analyzed in great detail. Secondly, new and extended methods of QSAR (quantitative structure-activity relationship) analysis have evolved to translate pharmacophore information into QSAR models that, in turn, can be used as virtual high-throughput screens for activity profiling of a library.

Quantitative component analysis of mixtures for risk assessment: application to eye irritation.

A methodology called quantitative component analysis of mixtures (QCAM) was used to analyze an existing set of product formulation data to determine if the irritating ingredients in the mixtures could be identified. Eye irritation scores, based on a rat model, for 18 mixtures having a composite total of 37 components, were analyzed by QCAM. QCAM relates a net toxicity measure of a mixture to the toxicities of the individual components of the mixture through linear, quadratic, and pairwise cross-component concentration-dependent interactions. A correlation model is established using a particular genetic algorithm employing either multidimensional linear regression or partial least-squares regression fitting. Cornea eye irritation and average eye irritation are well-explained in terms of a linear model of, at most, three components over the set of mixtures. Moreover, extensive cornea and average eye irritations are due to only one of these three components of the mixtures. Also, one of the three significant components was predicted to decrease the extent of eye irritation, and subsequently identified as an "anti-irritant" in contact lens solutions. A reasonable linear correlation model could also be developed for conjunctiva irritation, but no significant iris irritation model could be constructed. The addition of quadratic and/or cross-component concentration terms to a linear correlation model did not statistically improve the overall resultant model. The QCAM models permit estimation of the intrinsic (self) toxicity of each of the components of a mixture, and may aid in the reduction, and ultimate elimination, of the need for animal eye irritation studies.