Tolerability of N-chlorotaurine in comparison with routinely used antiseptics: an in vitro study on chondrocytes.

BACKGROUND: Currently, povidone-iodine (PVP-I) and hydrogen peroxide (H2O2) are frequently used antiseptics in joint infections, but the cytotoxic effects of these solutions are already reported. N-chlorotaurine (NCT) shows a broad-spectrum bactericidal activity and is well tolerated in various tissues, but its effect on human chondrocytes is unknown. The purpose of this study was to assess the cytotoxic effect of NCT, PVP-I, and H2O2 on human chondrocytes compared to a control group in an in vitro setting to get first indications if NCT might be a promising antiseptic in the treatment of septic joint infections for the future. MATERIAL AND METHODS: Chondrocytes extracted from human cartilage were incubated with various concentrations of NCT, PVP-I, and H2O2 for 5 and 30 min respectively. EZ4U cell viability kit was used according to the manufacturer's recommendations determining cell viability. To assess cell viability based on their nuclear morphology, cells were stained with acridine-orange and identified under the fluorescence microscope. RESULTS: EZ4U kit showed after 5 and 30 min of incubation a significant decrease in cell viability at NCT 1%, NCT 0.1%, PVP-I, and H2O2, but not for NCT 0.001% and NCT 0.01%. Acridine-orange staining likewise presented a significant decrease in vital cells for all tested solutions except NCT 0.001% and NCT 0.01% after 5 and 30 min of incubation. CONCLUSION: Our results demonstrate that NCT is well tolerated by chondrocytes in vitro at the tested lower NCT concentrations 0.01% and 0.001% in contrast to the higher NCT concentrations 1% and 0.1%, PVP-I (1.1%), and H2O2 (3%), for which a significant decrease in cell viability was detected. Considering that the in vivo tolerability is usually significantly higher, our findings could be an indication that cartilage tissue in vivo would tolerate the already clinically used 1% NCT solution. In combination with the broad-spectrum bactericidal activity, NCT may be a promising antiseptic for the treatment of septic joint infections.

Dupilumab-associated head and neck dermatitis shows a pronounced type 22 immune signature mediated by oligoclonally expanded T cells.

Dupilumab, an IL4R-blocking antibody, has shown clinical efficacy for atopic dermatitis (AD) treatment. In addition to conjunctivitis/blepharitis, the de novo appearance of head/neck dermatitis is now recognized as a distinct side effect, occurring in up to 10% of patients. Histopathological features distinct from AD suggest a drug effect, but exact underlying mechanisms remain unknown. We profiled punch biopsies from dupilumab-associated head and neck dermatitis (DAHND) by using single-cell RNA sequencing and compared data with untreated AD and healthy control skin. We show that dupilumab treatment was accompanied by normalization of IL-4/IL-13 downstream activity markers such as CCL13, CCL17, CCL18 and CCL26. By contrast, we found strong increases in type 22-associated markers (IL22, AHR) especially in oligoclonally expanded T cells, accompanied by enhanced keratinocyte activation and IL-22 receptor upregulation. Taken together, we demonstrate that dupilumab effectively dampens conventional type 2 inflammation in DAHND lesions, with concomitant hyperactivation of IL22-associated responses.

Antimicrobial potential and osteoblastic cell growth on electrochemically modified titanium surfaces with nanotubes and selenium or silver incorporation.

Titanium nanotube surfaces containing silver, zinc, and copper have shown antimicrobial effects without decreasing osteoblastic cell growth. In this in-vitro study we present first results on the biological evaluation of surface modifications by incorporating selenium and silver compounds into titanium-dioxide (TiO2) nanotubes by electrochemical deposition. TiO2-nanotubes (TNT) and Phosphate-doped TNT (pTNT) were grown on the surface of Ti6Al4V discs by anodization. Hydroxyapatite (HA), selenium (Se) and silver (Ag) compounds were incorporated by electrochemical deposition. Colony forming units of Staphylococcus epidermidis (DSM 3269) were significantly decreased in SepTNT (0.97 ± 0.18 × 106 CFU/mL), SepTNT-HA (1.2 ± 0.39 × 106 CFU/mL), AgpTNT (1.36 ± 0.42 × 106 CFU/mL) and Ag2SepTNT (0.999 ± 0.12 × 106 CFU/mL) compared to the non-modified control (2.2 ± 0.21 × 106 CFU/mL). Bacterial adhesion was calculated by measuring the covered area after fluorescence staining. Adhesion was lower in SepTNT (37.93 ± 12%; P = 0.004), pTNT (47.3 ± 6.3%, P = 0.04), AgpTNT (24.9 ± 1.8%; P < 0.001) and Ag2SepTNT (14.9 ± 4.9%; P < 0.001) compared to the non-modified control (73.7 ± 11%). Biofilm formation and the growth of osteoblastic cells (MG-63) was observed by using Crystal Violet staining. Biofilm formation was reduced in SepTNT (22 ± 3%, P = 0.02) and Ag2SepTNT discs (23 ± 11%, P = 0.02) compared to the non-modified control (54 ± 8%). In comparison with the non-modified control the modified SepTNT-HA and pTNT surfaces showed a significant higher covered area with osteoblastic MG-63-cells. Scanning electron microscope (SEM) images confirmed findings regarding bacterial and osteoblastic cell growth. These findings show a potential synergistic effect by combining selenium and silver with titanium nanotubes.

Utility of Absolute Quantification in Non-lesional Extratemporal Lobe Epilepsy Using FDG PET/MR Imaging.

The purpose of this study was to establish a non-invasive clinical PET/MR protocol using [18F]-labeled deoxyglucose (FDG) that provides physicians with regional metabolic rate of glucose (MRGlc) values and to clarify the contribution of absolute quantification to clinical management of patients with non-lesional extratemporal lobe epilepsy (ETLE). The study included a group of 15 patients with non-lesional ETLE who underwent a dynamic FDG PET study using a fully-integrated PET/MRI system (Siemens Biograph). FDG tracer uptake images were converted to MRGlc (µmol/100 g/min) maps using an image derived input function that was extracted based on the combined analysis of PET and MRI data. In addition, the same protocol was applied to a group of healthy controls, yielding a normative database. Abnormality maps for ETLE patients were created with respect to the normative database, defining significant hypo- or hyper-metabolic regions that exceeded ±2 SD of normal regional mean MRGlc values. Abnormality maps derived from MRGlc images of ETLE patients contributed to the localization of hypo-metabolic areas against visual readings in 53% and increased the confidence in the original clinical readings in 33% of all cases. Moreover, quantification allowed identification of hyper-metabolic areas that are associated with frequently spiking cortex, rarely acknowledged in clinical readings. Overall, besides providing some confirmatory information to visual readings, quantitative PET imaging demonstrated only a moderate impact on clinical management of patients with complex pathology that leads to epileptic seizures, failing to provide new decisive information that would have changed classification of patients from being rejected to being considered for surgical intervention.

Towards quantitative [18F]FDG-PET/MRI of the brain: Automated MR-driven calculation of an image-derived input function for the non-invasive determination of cerebral glucose metabolic rates.

Absolute quantification of PET brain imaging requires the measurement of an arterial input function (AIF), typically obtained invasively via an arterial cannulation. We present an approach to automatically calculate an image-derived input function (IDIF) and cerebral metabolic rates of glucose (CMRGlc) from the [18F]FDG PET data using an integrated PET/MRI system. Ten healthy controls underwent test-retest dynamic [18F]FDG-PET/MRI examinations. The imaging protocol consisted of a 60-min PET list-mode acquisition together with a time-of-flight MR angiography scan for segmenting the carotid arteries and intermittent MR navigators to monitor subject movement. AIFs were collected as the reference standard. Attenuation correction was performed using a separate low-dose CT scan. Assessment of the percentage difference between area-under-the-curve of IDIF and AIF yielded values within ±5%. Similar test-retest variability was seen between AIFs (9 ± 8) % and the IDIFs (9 ± 7) %. Absolute percentage difference between CMRGlc values obtained from AIF and IDIF across all examinations and selected brain regions was 3.2% (interquartile range: (2.4-4.3) %, maximum < 10%). High test-retest intravariability was observed between CMRGlc values obtained from AIF (14%) and IDIF (17%). The proposed approach provides an IDIF, which can be effectively used in lieu of AIF.

Zirconium Nitride Coating Reduced Staphylococcus epidermidis Biofilm Formation on Orthopaedic Implant Surfaces: An In Vitro Study.

BACKGROUND: One of the most commonly identified pathogens responsible for orthopaedic implant infection is Staphylococcus epidermidis, which can form biofilms on surfaces. Currently, orthopaedic implants made of various surface materials are available, each with features influencing osseointegration, biocompatibility, and adherence of bacteria to the surface, which is the first step in biofilm formation. The aim of this experimental study was to investigate the effect of a high tribologic-resistant 2.5-µm zirconium nitride top coat on an antiallergic multilayer ceramic-covered cobalt-chromium-molybdenum surface on the formation of S. epidermidis biofilm compared with other commonly used smooth and rough orthopaedic implant surface materials. QUESTIONS/PURPOSES: (1) When evaluating the surfaces of a cobalt-chromium-molybdenum (CoCrMo) alloy with a zirconium (Zr) nitride coating, a CoCrMo alloy without a coating, titanium alloy, a titanium alloy with a corundum-blasted rough surface, and stainless steel with a corundum-blasted rough surface, does a Zr coating reduce the number of colony-forming units of S. epidermidis in an in vitro setting? (2) Is there quantitatively less biofilm surface area on Zr-coated surfaces than on the other surfaces tested in this in vitro model? METHODS: To determine bacterial adhesion, five different experimental implant surface discs were incubated separately with one of 31 different S. epidermidis strains each and subsequently sonicated. Twenty test strains were obtained from orthopaedic patients undergoing emergency hip prosthesis surgeries or revision of implant infection and 10 further strains were obtained from the skin of healthy individuals. Additionally, one reference strain, S. epidermidis DSM 3269, was tested. After serial dilutions, the number of bacteria was counted and expressed as colony-forming units (CFUs)/mL. For biofilm detection, discs were stained with 0.1% Safranin-O for 15 minutes, photographed, and analyzed with computer imaging software. RESULTS: The lowest bacterial count was found in the CoCrMo + Zr surface disc (6.6 x 10 CFU/mL ± 4.6 x 10 SD) followed by the CoCrMo surface (1.1 x 10 CFU/mL ± 1.9 x 10 SD), the titanium surface (1.36 x 10 CFU/mL ± 1.8 x 10 SD), the rough stainless steel surface (2.65 x 10 CFU/mL ± 3.8 x 10 SD), and the rough titanium surface (2.1 x 10 CFU/mL ± 3.0 x 10 SD). The mean CFU count was lower for CoCrMo + Zr discs compared with the rough stainless steel surface (mean difference: 2.0 x 10, p = 0.021), the rough titanium alloy surface (mean difference: 1.4 x 10, p = 0.002), and the smooth titanium surface (mean difference: 7.0 x 10, p = 0.016). The results of biofilm formation quantification show that the mean covered area of the surface of the CoCrMo + Zr discs was 19% (± 16 SD), which was lower than CoCrMo surfaces (35% ± 23 SD), titanium alloy surface (46% ± 20 SD), rough titanium alloy surface (66% ± 23 SD), and rough stainless steel surface (58% ± 18 SD). CONCLUSIONS: These results demonstrate that a multilayer, ceramic-covered, CoCrMo surface with a 2.5-µm zirconium nitride top coat showed less S. epidermidis biofilm formation compared with other surface materials used for orthopaedic implants. CLINICAL RELEVANCE: CoCrMo with a 2.5-µm zirconium nitride top coat seems to be a promising surface modification technology able to reduce bacterial attachment on the surface of an implant and, hence, may further prevent implant infection with S. epidermidis biofilm formation.

Combined [18F]-Fluoroethylcholine PET/CT and 99mTc-Macroaggregated Albumin SPECT/CT Predict Survival in Patients With Intermediate-Stage Hepatocellular Carcinoma.

AIM: The aim of this study was to retrospectively analyze the prognostic value of combined Tc-macroaggregated albumin (MAA) SPECT/CT and [F]-fluoroethylcholine (FEC) PET/CT before radioembolization for survival of patients with intermediate-stage hepatocellular carcinoma. METHODS: Twenty-four patients with known hepatocellular carcinoma Barcelona Clinic Liver Cancer stage B were eligible for this analysis. All patients were scheduled for radioembolization and received a pretherapeutic [F]FEC PET/CT scan as well as Tc-MAA SPECT/CT for hepatopulmonary shunting. Laboratory and semiquantitative PET parameters and morphologic and metabolic (intersection) volumes of MAA and FEC were evaluated. Spearman correlation with overall survival, receiver operating curve analyses, univariate and multivariate Cox regression, and Kaplan-Meier-analysis was applied. RESULTS: All patients (5 female/19 male) are deceased within the observational period. Median survival was 395 days (±51 days; range, 23-1122 days). The percentage of hypervascularized metabolically active tumor volume (vascularized tumor ratio; defined as high MAA and FEC uptake) correlated significantly with survival. Vascularized tumor ratio was a significant predictor in univariate and multivariate analyses (P = 0.026; hazard ratio, 11.65; 95% confidence interval, 1.62-83.73; P = 0.015). Statistical significance was not reached by all other variables in multivariate analysis. Receiver operating curve analysis for 1-year survival revealed an area under the curve of 0.77 (P = 0.024) for vascularized tumor ratio. At a cutoff value of 9%, sensitivity, specificity, and positive and negative prediction were 83%, 67%, and 71% and 80% (P = 0.036). Patients with a higher tumor vascularization had a median survival of 274 ± 80 versus 585 ± 284 days (P = 0.015). CONCLUSIONS: Hepatocellular carcinoma with high vascularization in metabolic active areas as assessed by combined FEC PET/CT and Tc-MAA SPECT/CT represents an unfavorable subgroup with reduced overall survival after radioembolization.

[Amyloidosis in turkeys (Meleagris gallopavo f. domestica)--a case report]. / Amyloidose beim Truthuhn (Meleagris gallopavo f. domestica)--ein Fallbericht.

High prevalence of leg disorders in fattening meat turkey farm was observed. Four birds as well as tracheal and joint swabs were submitted to the Bavarian Health and Food Safety Authority in Oberschleissheim and to the Institute of Poultry Diseases, Faculty of Veterinary Medicine, Free University of Berlin. At the post-mortem, all birds showed an inflammation of the hock joints (intertarsal joint). The histopatholical investigations revealed a chronic inflammation of the joint and amyloid deposits in the joints in two cases as well as in different tissues (liver, spleen and kidneys) in another two cases. Using polymerase chain reaction, Ornithobacterium rhinotracheale-DNA could be detected in the examined tracheal and joint swabs. On the other hand, Mycoplasma gallisepticum- and Mycoplasma synoviae-DNA could not be detected. A causal correlation between the detected infectious agent and amyloidosis in relation to the leg disorders were discussed.

Evaluation of 6- and 12-month supervised exercise training on strength and endurance parameters in patients with peripheral arterial disease.

BACKGROUND: The classic symptom of peripheral arterial disease is the intermittent claudication (IC). Generally, endurance training is recommended to improve patients' walking performance. A potential benefit of the combination with strength training and the optimal duration of such an exercise program remain unclear. METHODS AND RESULTS: We evaluated the effects of a supervised exercise program combining endurance and strength training lasting 6 or 12 months in patients with IC. A total of 94 patients joined this study; 42 completed the 6-month training program (group A), whereas 52 patients completed the 12-month protocol (group B). Both groups exhibited a significant increase in all parameters evaluated, but greater benefit was found in the 12-month training group. The absolute claudication distance increased similarly by 27.5 and 29.5 %, respectively, in both groups (not significant); however, group B exhibited a greater increase in walking speed (12.1 vs. 5.3 %, p < 0.001). All strength parameters increased significantly in both the groups showing an increase for "pushing" by 90.0 % (group A) and 90.2 % (group B), for "pulling" by 64.2 % (group A) and 75.3 % (group B), and for "tiptoe standing" by 70.5 % (group A) and 113.7 % (group B; p < 0.05). CONCLUSION: The results of this study indicate that a combined exercise program significantly increases walking speed, absolute claudication distance, and muscle strength parameters. A greater benefit seems to result from a 12-month training program.

Differential bacterial load on components of total knee prosthesis in patients with prosthetic joint infection.

PURPOSE: The purpose of our study was to evaluate and quantify the bacterial adherence on different components of total knee prosthesis with the sonication culture method. METHODS: Explanted components of all patients with presumptive prosthetic or implant infection were treated by sonication separately in sterile containers to dislodge the adherent bacteria from the surfaces and cultured. The bacterial load of the different knee components (femur, tibia, PE-inlay and patella) was evaluated by counting of colony-forming units (CFU) dislodged from the components surfaces using the sonication culture method. RESULTS: Overall, 27 patients had positive sonication cultures of explanted total knee prostheses. Microorganisms were detected from 88 of 100 explanted components. Twenty femoral components were culture positive and 7 negative, 23 tibial components as well as 23 polyethylene (PE) platforms had positive microorganism detection from the surface. Staphylococcus epidermidis adhered to the highest number of components whereas Staphylococcus aureus yielded the highest load of CFU in the sonication cultures. Although not significant, PE-inlays and tibial components were most often affected. The highest CFU count was detected in polyethylene components. CONCLUSION: The sonication culture method is a reliable method to detect bacteria from the components. Additionally, the results demonstrate that bacterial adherence is not affecting a single component of knee prosthesis only. Thus, in septic revision surgery partial prosthetic exchange or exchange of single polyethylene components alone may be not sufficient.

Taurine chloramine induces apoptosis in human osteosarcoma cell lines.

Although combination of surgery with chemotherapy has noticeably improved the survival rate of osteosarcoma patients, the application of anticancer drugs is still associated with significant adverse reactions, for instance acquisition of drug-resistant phenotypes, necessitating the development of new chemotherapeutical agents. Therefore, the aim of this study was to research, if taurine chloramine (NCT) induces apoptosis in the osteosarcoma cell lines HOS, MG-63, and SAOS-2. Proliferation of osteosarcoma cells was detected with the "EZ4U Cell Proliferation and Cyotoxicity Assay" showing a time- and dose-dependent cytotoxic effect of NCT on these cell lines. After 3 h of incubation all cell lines showed significantly less cells at 5.5 mM NCT solutions, after 6 h at concentrations of 1.1 and 2.2 mM. Acridine-orange fluorescence nuclear staining showed characteristic features of apoptosis. DNA fragmentation was detected via ELISA, showing significant results for HOS and MG-63 after 6 h at an NCT concentration of 3.3 mM. Results of JC-1 mitochondrial FACS analysis presented a significant increase in apoptotic cells after 6 h at 3.3 mM for the tested cell lines. Summarized, the results of this study indicate that NCT is a promising agent in osteosarcoma therapy.

An in vitro model of biomaterial-augmented microfracture including chondrocyte-progenitor cell interaction.

BACKGROUND: Biomaterials, acting as scaffolds for cell migration and differentiation, may be used to improve outcomes after microfracture. Three mechanisms determine the success of such procedures and are tested herein: the general capacity of adult femoral mesenchymal progenitor cells (MPC) to differentiate into cartilage, their capacity to do so in a biomaterial, and finally potential interactions between MPC and autologous chondrocytes. METHODS: Human adult chondrocytes and MPC were obtained with informed consent and cultured individually or in co-culture on a collagenous biomaterial. Differentiation potential of MPC was assessed using PCR and proliferation and biosynthesis were compared to test for differences between individual cultures and co-cultures. Finally, potential interaction between chondrocytes and MPC was assessed by comparing the observed levels of proliferation and biosynthesis with those expected in independent growth. RESULTS: We found that adult femoral marrow-derived MPC have the potential to differentiate into multiple lineages, and, seeded in a biomaterial, show similar differentiation when compared with autologous chondrocytes. Finally, there was a strong indication for an interaction between MPC and chondrocytes in biosynthetic activity, which was twice as high as would be expected in independent cell activity. Proliferation rates were unaffected. CONCLUSION: Our study showed that biomaterial-augmented microfracture is a viable option in cartilage repair from a biological perspective because adult femoral MPC have a strong capacity to differentiate into chondrocytes, which is further enhanced by the surrounding cartilage. Failure in in vivo studies must be explained by other factors of the intra-articular environment, such as cytokines or biomechanics.