Osteocalcin enhances bone remodeling around hydroxyapatite/collagen composites

The effect of osteocalcin (OC), an extracellular bone matrix protein, on bone healing around hydroxyapatite/collagen composites was investigated. Cylindrical nanocrystalline hydroxyapatite implants of 2.5-mm diameter containing 2.5% biomimetically mineralized collagen type I were inserted press-fit into the tibial head of adult Wistar rats. To one implant group, 10 mug/g OC was added. Six specimens per group were analyzed at 2, 7, 14, 28, and 56 days. After 14 days, newly formed woven bone had reached the implant surface of the OC implants whereas a broad fibrous interface could still be observed around controls. Woven bone was formed directly around both implant groups after 28 days and had been replaced partially by lamellar bone around the OC implants only. No significant differences in total bone contact were seen between both groups after 56 days. The higher number of phagocytosing cells and osteoclasts characterized immunohistochemically with ED1, cathepsin D, and tartate-resistant alkaline phosphatase around the OC implants at the early stages of bone healing suggests an earlier onset of bone remodeling. The earlier and increased expression of bone-specific matrix proteins and multifunctional adhesion proteins (osteopontin, bone sialoprotein, CD44) at the interface around the OC implants indicates that OC may accelerate bone formation and regeneration. This study supports the observations from in vitro studies that OC activates both osteoclasts and osteoblasts during early bone formation.     

Complement system component dysregulation is a distinctive feature of COVID-19 disease: a prospective and comparative analysis of patients admitted to the emergency department for suspected COVID-19 disease

Journal of Thrombosis and Thrombolysis - The complement system (CS) plays a pivotal role in Coronavirus disease 2019 (COVID-19) pathophysiology. The objective of this study was to...     

First Revision of the German S3 Guideline 'Diagnosis, Therapy, and Follow-Up of Breast Cancer'

The development and implementation of evidence-based, interdisciplinary, consensus-based guidelines is a very important step towards decreasing breast cancer mortality and optimizing the process of early detection, diagnosis, therapy, and follow-up of breast cancer. A revised version of the German S3 guideline was published in February 2008. Different working groups, departments, and organizations participate as coeditors of the new guideline. To fulfill international methodic requirements, a systematic search of the literature with selection of new publications (used as evidence) in the established data bases (Medline, BIOSIS, Previews, CDSR, ACP Journal Club, DARE, CCTR, CINHAL) and the Guidelines International Network (GIN) was performed for the time period of 2003-2006. Varied specialist opinions concerning diagnosis, therapy, and follow-up of breast cancer were considered in formal consensus processes. In different steps, Nominal Group Process techniques, the Delphi technique, and formal consensus processes were used. Besides differently weighted, study-based recommendations, statements resulting from structured consensus finding by the interdisciplinary group - in terms of good clinical practice - were postulated.     

Prehospital cooling with hypothermia caps (PreCoCa): a feasibility study

Background  Animal studies suggest that the induction of therapeutic hypothermia in patients after cardiac arrest should be initiated as soon as possible after ROSC to achieve optimal neuroprotective benefit. A “gold standard” for the method of inducing hypothermia quickly and safely has not yet been established. In order to evaluate the feasibility of a hypothermia cap we conducted a study for the prehospital setting. Methods and results  The hypothermia cap was applied to 20 patients after out-of-hospital cardiac arrest with a median of 10 min after ROSC (25/75 IQR 8–15 min). The median time interval between initiation of cooling and hospital admission was 28 min (19–40 min). The median tympanic temperature before application of the hypothermia cap was 35.5°C (34.8–36.3). Until hospital admission we observed a drop of tympanic temperature to a median of 34.4°C (33.6–35.4). This difference was statistically significant (P < 0.001). We could not observe any side effects related to the hypothermia cap. 25 patients who had not received prehospital cooling procedures served as a control group. Temperature at hospital admission was 35.9°C (35.3–36.4). This was statistically significant different compared to patients treated with the hypothermia cap (P < 0.001). Conclusions  In summary we demonstrated that the prehospital use of hypothermia caps is a safe and effective procedure to start therapeutic hypothermia after cardiac arrest. This approach is rapidly available, inexpensive, non-invasive, easy to learn and applicable in almost any situation. C. Storm & J.C. Schefold are equally contributing first authors. ClinicalTrials.gov Identifier: NCT00398671     

Reduction of neointimal hyperplasia in porcine coronary arteries by 2-deoxy-d-glucose

Background

The drug eluting stents have been shown to play a substantial role in preventing in-stent restenosis. This study was initiated to determine the efficacy of 2-deoxy-d-glucose (2-DG) in an in-stent restenosis model for reducing neointimal hyperplasia after coronary stent placement.

Methods

In a porcine overstretch model, three kinds of stents were investigated (n = 12 per group): bare metal stents (BMS), rapamycin-eluted stents (RES), and BMS after intracoronary short-term application of 2-DG (DGS). After 42 days histomorphometric and histopathological analyses were performed.

Results

Neointimal thickness (BMS: 0.38 ± 0.08, RES: 0.24 ± 0.11, DGS: 0.15 ± 0.01), area stenosis (BMS: 47.39 ± 2.76, RES: 32.2 ± 2.08, DGS: 29.30 ± 2.98) did not differ after 42 days between the RES and DGS but were significantly lower as compared to BMS only. Lumen area (BMS: 3.15 ± 1.53, RES: 4.37 ± 1.72, DGS: 4.77 ± 2.14) was significantly higher in the DGS group in comparison to the BMS group. The calculated injury and inflammation scores were similar and re-endothelialization was confirmed in all groups.

Conclusions

This study could demonstrate that in porcine stent model neointimal hyperplasia and re-endothelialization after application of 2-DG are comparable to those seen in RES. Thus, 2-DG might be a promising clinical application for coronary stent coating.