Is part of the Bibliography
Effect of sonic hedgehog/β-TCP composites on bone healing within the critical-sized rat femoral defect
- The creation of entirely synthetically derived bone substitute materials which are as effective as autologous bone grafts is desirable. Osteogenesis involves the concerted action of several proteins within a signaling cascade. Hedgehog proteins act upstream of this cascade, inducing the expression of various bone morphogenetic proteins (BMPs) and promoting physiological bone healing. Therefore, the hypothesis that hedgehog signaling in bone defects improves bone healing more than BMP signaling alone was tested. Recombinant N-terminal sonic hedgehog protein (N-SHh), BMP-2 or a combination of the two was added to β-tricalcium phosphate (β-TCP) and 5-mm femoral midshaft defects in nude rats were filled with these composites. The defects were stabilized with mini-plates. After eight weeks, the animals were sacrificed and the femora were explanted. The radiological evaluation was followed by a three-point bending test and histological examination. BMP-2/β-TCP composites showed a trend of increased stiffness compared with the controls (β-TCP without protein). N-SHh/β-TCP composites had lower stiffness compared with the control group and the N-SHh/BMP-2/β-TCP composites also had lower average stiffness compared with the controls (all not significant). Histomorphometry, however, revealed abundant cartilage and bone core formation in the N-SHh-composite groups. The sum of the new cartilage and bone was highest in the combination group N-SHh/BMP-2 (not significant). The addition of N-SHh to bone substitute materials appears to delay bone healing at the applied concentration and observation time but also showed a trend for higher amounts of ossifying cartilage.
The role of recombinant epidermal growth factor and serotonin in the stimulation of tumor growth in a SCCHN xenograft model
- One challenge of squamous cell carcinoma of the head and neck (SCCHN) chemotherapy is a small percentage of tumor cells that arrest in the G0 phase of the cell cycle and are thus not affected by chemotherapy. This could be one reason for tumor recurrence at a later date. The recruitment of these G0-arresting cells into the active cell cycle and thus, proliferation, may increase the efficacy of chemotherapeutic agents. The aim of this study was to investigate whether stimulation with recombinant epidermal growth factor (EGF) or serotonin leads to an increased tumor cell proliferation in xenografts. Detroit 562 cells were injected into NMRI-Foxn1nu mice. Treatment was performed with 15 µg murine or human EGF, or 200 µg serotonin. The control mice were treated with Lactated Ringer's solution (5 mice/group). Tumor size was measured on days 4, 8 and 12 after tumor cell injection. The EGF stimulated mice showed a significantly higher tumor growth compared to the serotonin-stimulated mice and the untreated controls. In the present study, we show that it is possible to stimulate tumor cells in xenografts by EGF and thus, enhance cell proliferation, resulting in a higher tumor growth compared to the untreated control group. In our future investigations, we plan to include a higher number of mice, an adjustment of the EGF dosage and cell subanalysis, considering the heterogeneity of SCCHN tumors.
Thrombolysis in a stroke patient on dabigatran anticoagulation: case report and synopsis of published cases
- We present the case of an aphasic 77-year-old stroke patient with left distal M1 occlusion who received rt-PA for thrombolysis while on oral anticoagulant treatment with dabigatran (150 mg b.i.d.). Coagulation parameters were normal (thrombin time 20 s, aPTT 20 s, INR 1.08) and the patient improved from an NIHSS of 15 to 5 within 24 h with sonographic evidence of M1 recanalization. She did not develop intracranial bleeding complications but showed unusually large diffuse skin ecchymoses. In our report, we give an overview of all reported cases of thrombolysis under dabigatran anticoagulation and discuss the questions of medication adherence under novel oral anticoagulants (NOA) and the safety of NOA in terms of secondary intracerebral hemorrhage after stroke.
First human study in treatment of unresectable liver metastases from colorectal cancer with irinotecan-loaded beads (DEBIRI)
Martin G. Mack
Renate Maria Hammerstingl
Thomas J. Vogl
- The objective of this pilot clinical study was to assess the safety, technical feasibility, pharmacokinetic (PK) profile and tumour response of DC Bead™ with irinotecan (DEBIRI™) delivered by intra-arterial embolisation for the treatment of metastatic colorectal cancer. Eleven patients with unresectable liver metastases from CRC, tumour burden <30% of liver volume, adequate haematological, liver and renal function, performance status of <2 were included in this study. Patients received up to 4 sessions of TACE with DEBIRI at 3-week intervals. Feasibility of the procedure, safety and tumour response were assessed after each cycle. PK was measured after the first cycle. Patients were followed up to 24 weeks. Only mild to moderate adverse events were observed. DEBIRI is a technically feasibile procedure; no technical complications were observed. Average Cmax for irinotecan and SN-38 was 194 ng/ml and 16.7 ng/ml, respectively, with average t½ of 4.6 h and 12.4 h following administration of DEBIRI. Best overall response during the study showed disease control in 9 patients (2 patients with partial response and 7 with stable disease, overall response rate of 18%). Our study shows that transarterial chemoembolisation with irinotecan-loaded DC beads (DEBIRI) is safe, technically feasible and effective with a good PK profile.
Transfer entropy - a model-free measure of effective connectivity for the neurosciences
- Understanding causal relationships, or effective connectivity, between parts of the brain is of utmost importance because a large part of the brain’s activity is thought to be internally generated and, hence, quantifying stimulus response relationships alone does not fully describe brain dynamics. Past efforts to determine effective connectivity mostly relied on model based approaches such as Granger causality or dynamic causal modeling. Transfer entropy (TE) is an alternative measure of effective connectivity based on information theory. TE does not require a model of the interaction and is inherently non-linear. We investigated the applicability of TE as a metric in a test for effective connectivity to electrophysiological data based on simulations and magnetoencephalography (MEG) recordings in a simple motor task. In particular, we demonstrate that TE improved the detectability of effective connectivity for non-linear interactions, and for sensor level MEG signals where linear methods are hampered by signal-cross-talk due to volume conduction.
Static stretching of the hamstrings muscle for injury prevention in football codes: a systematic review
- Purpose: Hamstring injuries are common among football players. There is still disagreement regarding prevention. The aim of this review is to determine whether static stretching reduces hamstring injuries in football codes.
Methods: A systematic literature search was conducted on the online databases PubMed, PEDro, Cochrane, Web of Science, Bisp and Clinical Trial register. Study results were presented descriptively and the quality of the studies assessed were based on Cochrane’s ‘risk of bias’ tool.
Results: The review identified 35 studies, including four analysis studies. These studies show deficiencies in the quality of study designs.
Conclusion: The study protocols are varied in terms of the length of intervention and follow-up. No RCT studies are available, however, RCT studies should be conducted in the near future.
Acute injuries in student circus artists with regard to gender specific differences
Eileen M. Wanke
Jan David Alexander Groneberg
- Purpose: Student circus artists train as both artists and athletes with their bodies holding the key to professional success. The daily training load of student circus artists is often associated with maximum physical and psychological stress with injuries posing a threat to a potential professional career. The purpose of this study is the differentiated analysis and evaluation of work accidents in order to initiate the development of injury preventive programs.
Methods: The 17 years of data were obtained from standardized anonymous work accident records of the Berlin State Accident Insurance (UKB) as well as a State Artist Educational School (n = 169, Male: 70; Female: 99) from student artists. Evaluation and descriptive statistics were conducted with Excel 2007 and PASW Statistics 18.
Results: The injury risk seems to be relatively low (0.3 injuries/1000h). There are gender specific differences as to the location of injuries. Only 7% of the accidents demand a break of more than 3 days. Injury patterns vary depending on the activity and the employment of props/equipment. 75.2% of work accidents have multifactorial and 24.8% exogenous causes.
Conclusions: Because physical fitness is all important in the circus arts there are numerous options for injury prevention programs that should be realized subject to gender-specific differences. Follow-ups on chronic complaints and a more individual approach are indispensable due to the very specific activities in the circus arts.
Predictors of pulmonary failure following severe trauma: a trauma registry-based analysis
Emanuel Valentin Geiger
Helmut L. Laurer
- Background: The incidence of pulmonary failure in trauma patients is considered to be influenced by several factors such as liver injury. We intended to assess the association of various potential predictors of pulmonary failure following thoracic trauma and liver injury.
Methods: Records of 12,585 trauma patients documented in the TraumaRegister DGU® of the German Trauma Society were analyzed regarding the potential impact of concomitant liver injury on the incidence of pulmonary failure using uni- and multivariate analyses. Pulmonary failure was defined as pulmonary failure of ≥ 3 SOFA-score points for at least two days. Patients were subdivided according to their injury pattern into four groups: group 1: AIS thorax < 3; AIS liver < 3; group 2: AIS thorax ≥ 3; AIS liver < 3; group 3: AIS thorax < 3; AIS liver ≥ 3 and group 4: AIS thorax ≥ 3; AIS liver ≥ 3.
Results: Overall, 2643 (21%) developed pulmonary failure, 12% (n= 642) in group 1, 26% (n= 697) in group 2, 16% (n= 30) in group 3, and 36% (n= 188) in group 4. Factors independently associated with pulmonary failure included relevant lung injury, pre-existing medical conditions (PMC), sex, transfusion of more than 10 units of packed red blood cells (PRBC), Glasgow Coma Scale (GCS) ≤ 8, and the ISS. However, liver injury was not associated with an increased risk of pulmonary failure following severe trauma in our setting.
Conclusions: Specific factors, but not liver injury, were associated with an increased risk of pulmonary failure following trauma. Trauma surgeons should be aware of these factors for optimized intensive care treatment.
Identification of a novel methyltransferase, Bmt2, responsible for the N-1-methyl-adenosine base modification of 25S rRNA in Saccharomyces cerevisiae
- The 25S rRNA of yeast contains several base modifications in the functionally important regions. The enzymes responsible for most of these base modifications remained unknown. Recently, we identified Rrp8 as a methyltransferase involved in m1A645 modification of 25S rRNA. Here, we discovered a previously uncharacterized gene YBR141C to be responsible for second m1A2142 modification of helix 65 of 25S rRNA. The gene was identified by reversed phase–HPLC screening of all deletion mutants of putative RNA methyltransferase and was confirmed by gene complementation and phenotypic characterization. Because of the function of its encoded protein, YBR141C was named BMT2 (base methyltransferase of 25S RNA). Helix 65 belongs to domain IV, which accounts for most of the intersubunit surface of the large subunit. The 3D structure prediction of Bmt2 supported it to be an Ado Met methyltransferase belonging to Rossmann fold superfamily. In addition, we demonstrated that the substitution of G180R in the S-adenosyl-l-methionine–binding motif drastically reduces the catalytic function of the protein in vivo. Furthermore, we analysed the significance of m1A2142 modification in ribosome synthesis and translation. Intriguingly, the loss of m1A2142 modification confers anisomycin and peroxide sensitivity to the cells. Our results underline the importance of RNA modifications in cellular physiology.
Estrogen-Dependent Dynamic Profile of eNOS-DNA Associations in Prostate Cancer
Luis Jaime Castro-Vega
Maurizio C. Capogrossi
- In previous work we have documented the nuclear translocation of endothelial NOS (eNOS) and its participation in combinatorial complexes with Estrogen Receptor Beta (ERβ) and Hypoxia Inducible Factors (HIFs) that determine localized chromatin remodeling in response to estrogen (E2) and hypoxia stimuli, resulting in transcriptional regulation of genes associated with adverse prognosis in prostate cancer (PCa). To explore the role of nuclear eNOS in the acquisition of aggressive phenotype in PCa, we performed ChIP-Sequencing on chromatin-associated eNOS from cells from a primary tumor with poor outcome and from metastatic LNCaP cells. We found that: 1. the eNOS-bound regions (peaks) are widely distributed across the genome encompassing multiple transcription factors binding sites, including Estrogen Response Elements. 2. E2 increased the number of peaks, indicating hormone-dependent eNOS re-localization. 3. Peak distribution was similar with/without E2 with ≈ 55% of them in extragenic DNA regions and an intriguing involvement of the 5′ domain of several miRs deregulated in PCa. Numerous potentially novel eNOS-targeted genes have been identified suggesting that eNOS participates in the regulation of large gene sets. The parallel finding of downregulation of a cluster of miRs, including miR-34a, in PCa cells associated with poor outcome led us to unveil a molecular link between eNOS and SIRT1, an epigenetic regulator of aging and tumorigenicity, negatively regulated by miR-34a and in turn activating eNOS. E2 potentiates miR-34a downregulation thus enhancing SIRT1 expression, depicting a novel eNOS/SIRT1 interplay fine-tuned by E2-activated ER signaling, and suggesting that eNOS may play an important role in aggressive PCa.