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Objective: To treat instability caused by a genu recurvatum using ventral open wedge osteotomy of the distal femur., Indications: Knee instability caused by Genu recurvatum with femoral extension deformity., Contraindications: Inadequate blood flow to the lower extremity, soft tissue issues, obesity, osteoporosis., Surgical Technique: Through a primary medial approach to the distal femur, a ventral open wedge osteotomy is performed using chisel bunch formation and arthrodesis spreader. For symmetrical expansion, another lateral approach at the distal femur and insertion of another arthrodesis spreader is performed. Osteosynthesis was performed with an angle stable plate from the medial side and with additional stabilization using a 4-hole angle stable plate from the lateral side. The osteotomy gap was filled with a bone graft wedge., Postoperative Management: Partial weight-bearing of 20 kg was allowed for 6 weeks with passive exercise and lymphatic drainage. A hard frame orthosis for immobilization at 0-10-90° was fitted for 6 weeks. Radiographic controls were performed at 6 weeks, 3 months, and 1 year. After the last radiographic control, hardware was removed., Results: There are no reports in the current literature regarding the effect of a change in the sagittal plane at the distal femur on alignment, stability, and biomechanics of the knee. This case report shows that genu recurvatum with physiological posterior tibial slope can be successfully treated with anterior femoral flexion osteotomy. Hyperextension was completely eliminated at the follow-up examination after hardware removal after 12 months., (© 2024. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Background: While open wedge high tibial osteotomy (owHTO) is an established standard procedure to treat medial osteoarthritis of the knee in combination with varus deformity, it bears the risk of postoperative hardware failures and lateral cortical hinge fractures. This in turn can lead to an accelerated osteoarthritis, non-union, or a loss of correction accuracy. The purpose of the study was to evaluate the radiologic outcomes of owHTO with a carbon fiber reinforced poly-ether-ether-ketone (CF-PEEK) plate fixation in patients with medial osteoarthritis and varus deformity., Methods: Three hundred twenty-four consecutive patients (346 knees) who were treated with owHTO using the PEEKPower HTO plate were included in this retrospective study; 89.9% of the patients were overweight or obese. Patients were followed by conventional radiographs over a 12-month period. Typical plate-related results such as the time and quality of gap healing as well as the correction accuracy were analyzed. Furthermore, the number of lateral cortex fractures was determined., Results: Bony consolidation was observed after a mean gap healing time of 4.0 ± 1.7 months independent on the patients' weight (p = 0.2302). With increasing gap sizes, bony healing was significantly prolonged (p < 0.001). Additionally, patients with greater gap sizes had a significantly increased risk for a lateral cortex fracture (p = 0.0041). However, none of the patients had a non-union 1 year postoperative. A hinge fracture occurred in 30% of patients. Hinge fractures with Takeuchi grades I and II increased the gap healing time compared to no fracture (p = 0.0069 and p = 0.0002, respectively), but only 1.2% of patients with hinge fracture had a clinical relevant loss of correction ≥ 3 mm. No implant failures were found., Conclusions: Open wedge HTO using the PEEKPower HTO plate for patients with medial osteoarthritis of the knee in combination with tibial varus deformity leads to excellent bony consolidation also in cases with a hinge fracture, a gap size > 12 mm as well as for severely obese patients.

The availability of the complete genome sequence of Bacillus subtilis has allowed the prediction of all exported proteins of this Gram-positive eubacterium. Recently, approximately 180 secretory and 114 lipoprotein signal peptides were predicted to direct protein export from the cytoplasm. Whereas most exported proteins appear to use the Sec pathway, 69 of these proteins could potentially use the Tat pathway, as their signal peptides contain RR- or KR-motifs. In the present studies, proteomic techniques were applied to verify how many extracellular B. subtilis proteins follow the Tat pathway. Strikingly, the extracellular accumulation of 13 proteins with potential RR/KR-signal peptides was Tat-independent, showing that their RR/KR-motifs are not recognized by the Tat machinery. In fact, only the phosphodiesterase PhoD was shown to be secreted in a strictly Tat-dependent manner. Sodium azide-inhibition of SecA strongly affected the extracellular appearance of de novo synthesized proteins, including the lipase LipA and two other proteins with predicted RR/KR-signal peptides. The SecA-dependent export of pre-LipA is particularly remarkable, because its RR-signal peptide conforms well to stringent criteria for the prediction of Tat-dependent export in Escherichia coli. Taken together, our observations show that the Tat pathway makes a highly selective contribution to the extracellular proteome of B. subtilis.

Objective: Replication-deficient, recombinant adenovirus is used as a carrier for gene transfer, but it is unspecific and the onset of transgene expression is relatively late. Here, we evaluated the efficiency and selectivity of gene transfer mediated by recombinant Semliki Forest virus (SFV)., Methods: We compared the efficiency of a SFV-based vector with an adenoviral vector, using LacZ as a reporter gene. Firstly, the affinity for vascular smooth muscle cells, endothelial cells and cardiac myocytes was assessed. Secondly, we compared the time course of LacZ expression and cytotoxicity in vascular smooth muscle cells., Results: The SFV-based vector infects vascular smooth muscle cells and cardiomyocytes as efficiently as adenovirus. In contrast to adenovirus, SFV hardly transfers LacZ to endothelial cells (2.6% or less). SFV-mediated expression was visible after 1 h, reaching a maximum after 6 h. In contrast, adenovirus-mediated expression became visible after 6 h, and reached a maximum after 48-72 h. Both vectors were cytotoxic., Conclusions: We demonstrate that SFV efficiently transfers LacZ to vascular smooth muscle cells and cardiomyocytes, but not to endothelial cells. In contrast, adenovirus causes efficient transgene expression in all cell types tested. Furthermore, SFV-mediated expression is faster than adenovirus-mediated expression. Therefore, SFV-mediated gene transfer may be a suitable alternative to adenovirus, providing a fast expression in non-endothelial cardiovascular cell types.

Haloalkane dehalogenase catalyzes the hydrolytic cleavage of carbon-halogen bonds in short-chain haloalkanes. Two tryptophan residues of the enzyme (Trp125 and Trp175) form a halide-binding site in the active-site cavity, and were proposed to play a role in catalysis. The function of these residues was studied by replacing Trp125 with phenylalanine, glutamine or arginine and Trp175 by glutamine using site-directed mutagenesis. All mutants except Trp125-->Phe showed a more than 10-fold reduced kcat and much higher Km values with 1,2-dichloroethane and 1,2-dibromoethane than the wild-type enzyme. Fluorescence quenching experiments showed a decrease in the affinity of the mutant enzymes for halide ions. The 2H kinetic isotope effect observed with the wild-type enzyme in deuterium oxide was lost in the active mutants, except the Trp125-->Phe enzyme. The results indicate that both tryptophans are involved in stabilizing the transition state during the nucleophilic substitution reaction that causes carbon-halogen bond cleavage.

Haloalkane dehalogenase hydrolyses various 1-halo-n-alkanes to the corresponding alcohols by covalent catalysis with formation of an alkyl-enzyme intermediate. The carboxylate function of the nucleophilic aspartate (Asp-124) that displaces the halogen during formation of the intermediate was changed to an amide by site-directed mutagenesis (Asp-124-->Asn). Activity measurements and analysis of peptides containing the nucleophilic residue showed that the mutant enzyme was inactive, but that the activity increased by rapid deamidation of the asparagine residue, yielding wild type enzyme. There was no indication for isoaspartate formation during this process. The results suggest that a water molecule that is located close to the carboxyl function of Asp-124 in the X-ray structure is highly reactive and is responsible for the observed deamidation.

Haloalkane dehalogenase catalyzes the hydrolytic cleavage of carbon-halogen bonds in a broad range of halogenated aliphatic compounds. The X-ray structure suggests that Asp124, which is located close to an internal cavity, carries out a nucleophilic attack on the C alpha of the substrate, releasing the halogen. To study the mechanism of hydrolysis, this aspartate residue was mutated to alanine, glycine, or glutamate. The mutant enzymes showed no activity toward 1,2-dichloroethane and 1,2-dibromoethane. Incubation of purified wild-type dehalogenase with 1,2-dichloroethane in the presence of H2(18)O resulted in the incorporation of 18O in 2-chloroethanol and in the carboxylate group of Asp124. This shows that the reaction proceeds by covalent catalysis with the formation of an alkyl-enzyme intermediate that is hydrolyzed by attack of solvent water on the carbonyl carbon of Asp124. On the basis of amino acid sequence similarity between haloalkane dehalogenase and epoxide hydrolases, it is proposed that a conserved aspartate residue is also involved in covalent catalysis by the latter enzymes.

Microorganisms that can utilize halogenated compounds as a growth substrate generally produce-enzymes whose function is carbon-halogen bond cleavage. Based on substrate range, reaction type and gene sequences, the dehalogenating enzymes can be classified in different groups, including hydrolytic dehalogenases, glutathione transferases, monooxygenases and hydratases. X-ray crystallographic and biochemical studies have provided detailed mechanistic insight into the action of haloalkane dehalogenase. The essential features are nucleophilic substitution of the halogen by a carboxylate group and the presence of a distinct halogen binding site, formed by tryptophan residues. This review summaries current knowledge on a variety of other dehalogenating enzymes and indicates the existence of a widespread and diverse microbial potential for dechlorination of natural and xenobiotic halogenated compounds.

The article reports on three gastric leiomyomas, each belonging to a different histological sub-type. The influence of imaging methods is described taking sonography and computed tomography into account which are also used for diagnostic purposes.

To determine factors that influence the accuracy of echocardiographically estimated right ventricular volume and to improve the echocardiographic input information by applying image enhancement techniques, quantitative contrast echocardiography (4-chamber view) and biplane angiocardiography were performed in 23 children during routine diagnostic cardiac catheterization. Volumes calculated on the basis of unprocessed and processed echocardiographic cross sections (area-length method and sphere model) underestimated angiocardiographic volumes significantly (p less than 0.01), and more so in end-diastole (50.6%) than in end-systole (35.9%). Thus, ejection fraction was significantly (p less than 0.01) underestimated; mean values were 0.48 +/- 0.12 and 0.60 +/- 0.08, respectively. The best comparison between echocardiography and angiocardiography at end-diastole was achieved with the sphere model using image enhancement techniques and injection of contrast media, where y = 0.54x - 6.8, r = 0.97, sy.x = 7.3. Correlations, however, in which unprocessed echocardiograms were used showed only slightly less good correlations. With the 6 image-enhancement techniques, a more homogeneous structure of the image and a more distinct outline of the internal surface was achieved. The statistical error improved only slightly. The echocardiographic 4-chamber view allows right ventricular volume determination with an acceptable accuracy. Its underestimation is related to inadequate visualization of trabeculations and mainly to the models used. Application of image enhancement techniques allows easier outlining of the internal cavity surface. The advantage gained by the combination of contrast infection and image enhancement techniques does not warrant the routine central injection of available contrast material.

A 47-year-old man reported increasing feeling of fullness in the upper abdomen and pain in both flanks, radiating to both groins. Physical examination did not reveal any abnormalities. Biochemical tests demonstrated hypertriglyceridaemia and hypercholesteremia. Urography, abdominal ultrasound, computed and magnetic resonance tomography revealed a large, fat-containing tumour of the right adrenal. At operation a soft, somewhat elastic adrenal tumour, about 10 cm in diameter, was removed. Histologically it proved to be a myelolipoma. The correct preoperative diagnosis of such a tumour is possible in about 90% of cases.