Treatment of infected tibial nonunion with bone defect using central bone grafting technique

Treatment of infected tibial nonunion with bone defect represents a challenge for every orthopaedic surgeon. Various methods of treatment have been described for nonunions with infection, bone loss or both. One of them is the central bone grafting technique, which is a safe and effective treatment for nonunions of the tibia. The technique involves placement of autogenous cancellous bone from the iliac crest on the anterior surface of the interosseous membrane with the aim of creating a tibiofibular synostosis. We present the results of uncontrolled, retrospective and continuous series of ten patients treated by a central bone grafting technique for infected tibial nonunion with bone loss. Mean follow-up period was 12 (10-15) years. Most injuries were a result of war injuries. Clinically and radiologically confirmed bony healing with total consolidation of the graft was achieved in all patients within a period of 10-12 months without further bone grafting. The newly-formed bone mass was able to fulfil the mechanical and functional demands of everyday life activities. Once again, the central bone grafting technique has shown to be a safe, reliable and effective method of treatment for infected tibial nonunion with bone defect.     

Results of the surgical reconstruction of the anterior cruciate ligament

Results of the surgical reconstruction of the anterior cruciate ligament (ACL), using as a graft fourfold hamstring tendons (gracilis and semitendinosus) and middle third of the patellar ligament, were compared. In all patients that were participating in this study clinical examination and magnetic resonance showed ACL rupture, and apart from the choice of the graft, surgical technique was identical. We evaluated 112 patients with implemented patellar ligament graft and fourfold hamstring tendons graft six months after the procedure. Both groups were similar according to age, sex, activity level, knee instability level and rehabilitation program. The results showed that there was no significant difference between groups regarding Lysholm Knee score, IKDC 2000 score, activity level, musculature hypotrophy, and knee joint stability 6 months after the surgery. Anterior knee pain incidence is significantly higher in the group with patellar ligament graft (44% vs. 21%). Both groups had a significant musculature hypotrophy of the upper leg of the knee joint that was surgically treated, six months after the procedure. Both grafts showed good subjective and objective results.     

Heterozygous carriage of a dysfunctional Toll-like receptor 9 allele affects CpG oligonucleotide responses in B cells

Toll-like receptors (TLR) are employed by the innate immune system to detect microbial pathogens based on conserved microbial pathogen molecules. For example, TLR9 is a receptor for CpG-containing microbial DNA, and its activation results in the production of cytokines and type I interferons from human B cells and plasmacytoid dendritic cells, respectively. Both are required for mounting an efficient antibacterial or antiviral immune response. These effects are mimicked by synthetic CpG oligodeoxynucleotides (ODN). Although several hyporesponsive TLR9 variants have been reported, their functional relevance in human primary cells has not been addressed. Here we report a novel TLR9 allele, R892W, which is hyporesponsive to CpG ODN and acts as a dominant-negative in a cellular model system. The R892W variant is characterized by increased MyD88 binding and defective co-localization with CpG ODN. Whereas primary plasmacytoid dendritic cells isolated from a heterozygous R892W carrier responded normally to CpG by interferon-α production, carrier B cells showed impaired IL-6 and IL-10 production. This suggests that heterozygous carriage of a hyporesponsive TLR9 allele is not associated with complete loss of TLR9 function but that TLR9 signals elicited in different cell types are regulated differently in human primary cells.     

Identification and purification of a stress associated nuclear carbohydrate binding protein (Mr 33000) from rat liver by application of a new photoreactive carbohydrate probe

A photoreactive -D-glucose probe has been designed for the specific detection of carbohydrate binding proteins (CBPs). The probe consists of four parts: (i) an -D-glucose moiety; (ii) the digoxigenin tag; (iii) the photoreactive cross-linker; and (iv) the lysyl-lysine backbone. After incubation with lectins in the dark, the probe is activated and cross-linked to the CBPs after being treated by several flashes.Using this method we have identified a new -D-glucose CBP ofM _r=33000, termed CBP33, in the nuclei of rats exposed to transient immobilization stress. Monoclonal antibodies were raised against the partially purified protein and subsequently used to enrich CBP33. It was purified (>2400-fold) to apparent homogeneity from a 0.6M nuclear salt extract by two subsequent affinity chromatography steps (antibody-affinity as well as -D-glucose affinity column).Abbreviations BSA bovine serum albumin - CBP carbohydrate binding protein - DIG digoxigenin - Gal galactose - Glc glucose - Lys lysine - PAGE polyacrylamide gel electrophoresis - SDS sodium dodecyl sulphate.     

Analysis of 12 X-STR loci in the population of south Croatia

The aim of the study was to assess forensic pertinence of 12 short tandem repeats (STRs) on X-chromosome in south Croatia population. Investigator^® Argus X-12 kit was used to co-amplify 12 STR loci belonging to four linkage groups (LGs) on X-chromosome in 99 male and 98 female DNA samples of unrelated donors. PCR products were analyzed by capillary electrophoresis. Population genetic and forensic parameters were calculated by the Arlequin and POPTREE2 software, and an on-line tool available at ChrX-STR.org. Hardy–Weinberg equilibrium was confirmed for all X-STR markers in female samples. Biallelic patterns at DXS10079 locus were detected in four male samples. Polymorphism information content for the most (DXS10135) and the least (DXS8378) informative markers was 0.9212 and 0.6347, respectively. In both male and female samples, combined power of discrimination exceeded 0.999999999. As confirmed by linkage disequilibrium test, significant association of marker pair DXS10074-DXS10079 (P?=?0.0004) within LG2 and marker pair DXS10101-DXS10103 (P?=?0.0003) within LG3 was found only in male samples. Number of observed haplotypes in our sample pool amounted 3.01, 7.53, 5 and 3.25% of the number of possible haplotypes for LG1, LG2, LG3 and LG4, respectively. According to haplotype diversity value of 0.9981, LG1 was the most informative. In comparison of south Croatia with 26 world populations, pair-wise \({{\text{F}}_{\text{ST}}}^{\text{*}}\) values increase in parallel with geographical distance. Overall statistical assessment confirmed suitability of Investigator^® Argus X-12 kit for forensic casework in both identification and familial testing in the population of south Croatia.     

Central chemoreflex sensitivity and sympathetic neural outflow in elite breath-hold divers.

Repeated hypoxemia in obstructive sleep apnea patients increases sympathetic activity, thereby promoting arterial hypertension. Elite breath-holding divers are exposed to similar apneic episodes and hypoxemia. We hypothesized that trained divers would have increased resting sympathetic activity and blood pressure, as well as an excessive sympathetic nervous system response to hypercapnia. We recruited 11 experienced divers and 9 control subjects. During the diving season preceding the study, divers participated in 7.3 +/- 1.2 diving fish-catching competitions and 76.4 +/- 14.6 apnea training sessions with the last apnea 3-5 days before testing. We monitored beat-by-beat blood pressure, heart rate, femoral artery blood flow, respiration, end-tidal CO(2), and muscle sympathetic nerve activity (MSNA). After a baseline period, subjects began to rebreathe a hyperoxic gas mixture to raise end-tidal CO(2) to 60 Torr. Baseline MSNA frequency was 31 +/- 11 bursts/min in divers and 33 +/- 13 bursts/min in control subjects. Total MSNA activity was 1.8 +/- 1.5 AU/min in divers and 1.8 +/- 1.3 AU/min in control subjects. Arterial oxygen saturation did not change during rebreathing, whereas end-tidal CO(2) increased continuously. The slope of the hypercapnic ventilatory and MSNA response was similar in both groups. We conclude that repeated bouts of hypoxemia in elite, healthy breath-holding divers do not lead to sustained sympathetic activation or arterial hypertension. Repeated episodes of hypoxemia may not be sufficient to drive an increase in resting sympathetic activity in the absence of additional comorbidities.     

Heterotrimeric G-proteins activate Cl- channels through stimulation of a cyclooxygenase-dependent pathway in a model liver cell line.

Circulating hormones produce rapid changes in the Cl(-) permeability of liver cells through activation of plasma membrane receptors coupled to heterotrimeric G-proteins. The resulting effects on intracellular pH, membrane potential, and Cl(-) content are important contributors to the overall metabolic response. Consequently, the purpose of these studies was to evaluate the mechanisms responsible for G-protein-mediated changes in membrane Cl(-) permeability using HTC hepatoma cells as a model. Using patch clamp techniques, intracellular dialysis with 0.3 mm guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS) increased membrane conductance from 10 to 260 picosiemens/picofarads due to activation of Ca(2+)-dependent Cl(-) currents that were outwardly rectifying and exhibited slow activation at depolarizing potentials. These effects were mimicked by intracellular AlF(4)(-) (0.03 mm) and inhibited by pertussis toxin (PTX), consistent with current activation through Galpha(i). Studies using defined agonists and inhibitors indicate that Cl(-) channel activation by GTPgammaS occurs through an indomethacin-sensitive pathway involving sequential activation of phospholipase C, mobilization of Ca(2+) from inositol 1,4,5-trisphosphate-sensitive stores, and stimulation of phospholipase A(2) and cyclooxygenase (COX). Accordingly, the conductance responses to GTPgammaS or to intracellular Ca(2+) were inhibited by COX inhibitors. These results indicate that PTX-sensitive G-proteins regulate the Cl(-) permeability of HTC cells through Ca(2+)-dependent stimulation of COX activity. Thus, receptor-mediated activation of Galpha(i) may be essential for hormonal regulation of liver transport and metabolism through COX-dependent opening of a distinct population of plasma membrane Cl(-) channels.     

Isoforms of the human PDZ-73 protein exhibit differential tissue expression

Patients with renal and colon cancer frequently develop IgG autoantibodies toward the NY-CO-38/PDZ-73 antigen, a protein of 652 amino acids (73 kDa) which contains three copies of the PDZ protein-protein interaction domain. The gene encoding PDZ-73 mapped to chromosome 11p15.4-p15.1. Additional tissue-specific isoforms were identified: PDZ-45, which lacks the third PDZ domain and the putative PEST protein degradation motif, is expressed in kidney, colon, small intestine, brain and testis; PDZ-54 and PDZ-59, which also lack the third PDZ domains, have unique carboxyl terminal amino acids and are expressed in brain, kidney, bladder, colon cancer and renal cancer; and a putative PDZ-37 isoform, containing only the third PDZ domain, that is expressed in the central nervous system. Immunohistochemical staining with anti-PDZ 73 monoclonal antibodies showed strong cytoplasmic reactivity in epithelial cells of the small intestine, colon and kidney tubules, with a prominent apical staining pattern in cells of the small intestine. The reactivity pattern of the antibodies with various tissues correlated with the mRNA expression pattern of the PDZ-45 isoform. The existence of multiple PDZ-73 isoforms with variations in tissue distribution, PDZ domains, protein degradation sequences and carboxyl terminal structure indicate that these isoforms have distinct tissue-specific functions.