Acta Chir Orthop Traumatol Cech
March 2023
PURPOSE OF THE STUDY The study retrospectively reviews the outcomes of patella stabilisation surgeries performed at our department in the period 2010-2020. It aimed to provide a more thorough evaluation, to compare the respective types of MPFL reconstruction and to confirm the beneficial effect of tibial tubercle ventromedialization on patella height. MATERIAL AND METHODS In the period 2010-2020, a total of 72 stabilisation surgeries of patellofemoral joint in 60 patients with objective patellar instability (OPI) were performed at our department.
View Article and Find Full Text PDFActa Chir Orthop Traumatol Cech
November 2021
PURPOSE OF THE STUDY The purpose of the study is to analyse the number of adult patients treated in our department for native joint septic arthritis and to outline guidelines for antibiotic therapy. MATERIAL AND METHODS From the beginning of 2003 to the end of 2020, a total of 36,342 surgeries were performed at our department. We retrospectively reviewed and analysed all surgeries for native joint septic arthritis (a total of 538 surgical interventions).
View Article and Find Full Text PDFActa Chir Orthop Traumatol Cech
September 2021
PURPOSE OF THE STUDY The purpose of the study is to verify the correct alignment of components of the Oxford medial unicompartmental knee arthroplasty using the Zimmer Microplasty® instrumentation at the beginning of the learning curve. The implantation of prosthetic components of partial knee arthroplasty in proper alignment has an effect on long-term survival of the prosthesis and should eliminate the occurrence of frequent complications. MATERIAL AND METHODS The study group includes 20 patients, 9 men with the mean age of 68 years (range 62-78 years) and 11 women with the mean age of 69 years (range 52-81 years).
View Article and Find Full Text PDFPURPOSE OF THE STUDY Tantallum trabecular metal implants (Trabecular Metal Technology - TMT) considerably changed the acetabular reconstruction options in revision surgeries with extensive bone defects and distorted pelvic ring integrity. The purpose of this study is to ascertain the short-term to medium-term outcomes of acetabular reconstruction through TMT implants in patients with Paprosky type 3a and 3b acetabular defects and in case of pelvic discontinuity. MATERIAL AND METHODS The prospective monocentric study included patients in whom the revision of acetabular components in total hip arthroplasty was performed, the acetabular defect was classified as Paprosky 3a and higher, a TMT implant was used for reconstruction, and the follow-up period was at least 2 years after surgery.
View Article and Find Full Text PDFReaxFF is a computationally efficient force field to simulate complex reactive dynamics in extended molecular models with diverse chemistries, if reliable force-field parameters are available for the chemistry of interest. If not, they must be optimized by minimizing the error ReaxFF makes on a relevant training set. Because this optimization is far from trivial, many methods, in particular, genetic algorithms (GAs), have been developed to search for the global optimum in parameter space.
View Article and Find Full Text PDFTularemia caused by is a zoonotic infection of the Northern Hemisphere that mainly affects the skin, lymph nodes, bloodstream, and lungs. Other manifestations of tularemia are very rare, especially those with musculoskeletal involvement. Presenting in 2016, we diagnosed two cases of periprosthetic knee joint infections (PJI) caused by in Europe (one in Switzerland and one in the Czech Republic).
View Article and Find Full Text PDFJ Chem Theory Comput
January 2018
Computational studies of the reaction mechanisms of various enzymes are nowadays based almost exclusively on hybrid QM/MM models. Unfortunately, the success of this approach strongly depends on the selection of the QM region, and computational cost is a crucial limiting factor. An interesting alternative is offered by empirical reactive molecular force fields, especially the ReaxFF potential developed by van Duin and co-workers.
View Article and Find Full Text PDFJ Chem Theory Comput
December 2016
Hybrid QM/MM computational studies can provide invaluable insight into the mechanisms of enzymatic reactions that can be exploited for rational drug design. Various approaches are available for such studies. However, their strengths and weaknesses may not be immediately apparent.
View Article and Find Full Text PDFThe glycosylation of cell surface proteins plays a crucial role in a multitude of biological processes, such as cell adhesion and recognition. To understand the process of protein glycosylation, the reaction mechanisms of the participating enzymes need to be known. However, the reaction mechanism of retaining glycosyltransferases has not yet been sufficiently explained.
View Article and Find Full Text PDFSolvent-driven aggregation of a series of porphyrin derivatives was studied by UV/Vis and circular dichroism spectroscopy. The porphyrins are characterised by the presence in the meso positions of steroidal moieties further conjugated with glucosyl groups. The presence of these groups makes the investigated macrocycles amphiphilic and soluble in aqueous solvent, namely, dimethyl acetamide/water.
View Article and Find Full Text PDFo-Phthaldialdehyde was used in combination with a series of six thiosugars for the pre-column chiral derivatization of selected primary amino acids. The diastereomers were resolved on a conventional reversed-phase column and with fluorescence detection. A surprisingly effective resolution of 1-isoindolyl-(1-thioglycosides) derived from 1-thio-beta-L-fucose was observed.
View Article and Find Full Text PDFThe reaction system containing Cu(II), hydrogen peroxide and D-arabinono-1,4-lactone was found to be effective in the decolorization and reduction of toxicity of azo, thiazine-, triphenylmethane- and anthraquinone-based synthetic dyes. More than 85% decolorization was obtained with 100ppm Acridine Orange, Azure B, Chicago Sky Blue 6B, Crystal Violet, Evans Blue, Poly B-411, Reactive Blue 2, Reactive Blue 5, and Remazol Brilliant Blue R incubated for 24h in the presence of 10mM CuSO(4), 20mM D-arabinono-1,4-lactone and 80 mM H(2)O(2). The rate of decolorization was not affected by pH in the range of 3-9.
View Article and Find Full Text PDFAbstract Glycodendrimers bearing Tn (α-D-GalNAc-(1→O)-Ser/Thr), an identified tumor-associated carbohydrate antigen, hold promise in the post-surgery treatment of a variety of tumors such as metastatic breast cancer. We used molecular dynamics (MD) techniques to examine structural differences taking place during synthesis of two classes of tetravalent Multiple Antigen Glycopeptides (MAG) that differ only by the y-Abu insert in the structure of the oligolysine core. Each of the selected intermediates of the synthesis was modeled, subjected to the 2 ns run in N,N'-dimethylformamide (DMF) and geometrically characterized.
View Article and Find Full Text PDFThe crystallization of calcium carbonate into microspheres has been accomplished using the rationally-designed, doubly-hydrophilic block copolypeptide poly(Nepsilon-2[2-(2-methoxyethoxy)ethoxy]acetyl-L-lysine)(100)-b-poly(L-aspartate sodium salt)30 as a structure-directing agent.
View Article and Find Full Text PDFGlycodendrimers bearing Tn (alpha-D-GalNAc-(1 --> O)-Ser/Thr), an identified tumor-associated carbohydrate antigen, hold promise in the post-surgery treatment of a variety of tumors such as metastatic breast cancer. We used molecular dynamics (MD) techniques to examine structural differences taking place during synthesis of two classes of tetravalent Multiple Antigen Glycopeptides (MAG) that differ only by the gamma-Abu insert in the structure of the oligolysine core. Each of the selected intermediates of the synthesis was modeled, subjected to the 2 ns run in N,N'-dimethylformamide (DMF) and geometrically characterized.
View Article and Find Full Text PDFSelected azo, acridine, triphenyl methane, anthraquinone and thiazine-based dyes were decolorized using a catalytic system consisting of Cu(II)/glucaric acid/H(2)O(2). More than 90% decolorization was obtained with 100 ppm Acridine Orange, Azure B, Chicago Sky Blue, Crystal Violet, Methyl Orange, Poly B-411, Reactive Black 5, Reactive Blue 2, and Remazol Brilliant Blue R within 24 h. Seventy to eighty percent decolorization was achieved within the first 6 h.
View Article and Find Full Text PDFThis paper reports the synthesis and characterization of a variety of ruthenium complexes coordinated with phosphine and N-heterocyclic carbene (NHC) ligands. These complexes include several alkylidene derivatives of the general formula (NHC)(PR(3))(Cl)(2)Ru=CHR', which are highly active olefin metathesis catalysts. Although these catalysts can be prepared adequately by the reaction of bis(phosphine) ruthenium alkylidene precursors with free NHCs, we have developed an alternative route that employs NHC-alcohol or -chloroform adducts as "protected" forms of the NHC ligands.
View Article and Find Full Text PDFTreatment of 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-1-thio-beta-D-glucopyranose with 1,6-anhydro-3,4-dideoxy-2-O-p-toluenesulfonyl-beta-D-erythro-hex-3-enopyranose gave 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-beta-D-glucopyranosyl-(1-->4)-1,6-anhydro-2,3-dideoxy-4-thio-beta-D-erythro-hex-2-enopyranose in 86% yield. Its 1,6-anhydride bond was cleaved with methanol to give a mixture of methyl glycosides (alpha/beta approximately 5:1), from which the alpha anomer was separated by crystallization and converted into its 6-acetate, 6-methanesulfonate, or deacetylated to obtain the corresponding free methyl thiodisaccharide. The structure of the new compounds was confirmed by 1H and 13C NMR spectra.
View Article and Find Full Text PDFThe preparation of affinity sorbents containing immobilized iodinated derivatives of L-tyrosine for the affinity chromatography of porcine pepsin is described. The ligand was coupled either to Sepharose 4B or bead cellulose after the divinylsulfone activation or to Sepharose 4B after the activation with 2,4,6-trichloro-1,3,5-triazine. The highest capacity for porcine pepsin was found in the case of 3,5-diiodo-L-tyrosine coupled to divinylsulfone-activated Sepharose.
View Article and Find Full Text PDFIn recent years, the olefin metathesis reaction has attracted widespread attention as a versatile carbon-carbon bond-forming method. Many new applications have become possible because of major advances in catalyst design. State-of-the-art ruthenium catalysts are not only highly active but also compatible with most functional groups and easy to use.
View Article and Find Full Text PDFWhen the series of 2-, 3-, and 4-(benzylamino)-2-, 3-, and 4-deoxy derivatives of 1,6-anhydro-beta-D-hexopyranoses in the D-gluco, D-lyxo, and D-arabino configurations were reacted with diisopropyl azodicarboxylate, N-benzyl groups were selectively cleaved in the presence of O-benzyl groups. The yields ranged from 51 to 97%. The debenzylation of some aliphatic benzylamines is also discussed.
View Article and Find Full Text PDF2-Chloroethyl 1-thio-beta-D-galactopyranoside and the corresponding 1-thio-beta-D-glucopyranoside have been found to be suitable glycosylating agents for the preparation of different types of glycoconjugates. Glycosylation of bovine serum albumin and chymotrypsin were chosen as examples of an application of the described compounds. The glycosylating agents can modify not only amino groups, but also alkyl hydroxyl and aryl hydroxyl groups, as was shown in experiments with model water soluble and water insoluble polyacrylamide copolymers.
View Article and Find Full Text PDFPotentiometric and spectroscopic studies of complexes of Cu2+ with two 1,6-anhydro derivatives of aminosugars, 1,6-anhydro-2-deoxy-2N-methylamino-beta-D-mannopyranose and 1,6-anhydro-3,4-epimino-beta-D-altropyranose, showed that the epimino nitrogen donor binds Cu(II) ions, but its position prevents formation of stable chelate complexes. The other ligand is very effective in metal ion coordination, but contrary to the homologous glucosamine derivative, it does not form any dimeric species.
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