Biomechanical comparisons of three minimally invasive Achilles tendon percutaneous repair suture techniques.

BACKGROUND: While no gold standard exists for the management of Achilles tendon ruptures, surgical repair is common in healthy and active patients. Minimally invasive repair methods have become increasingly popular, while biomechanical equivalency hasn't been proven yet. METHODS: A mid-substance Achilles tendon rupture was created 6 cm proximal to the calcaneal insertion in 27 fresh-frozen cadaveric ankles. Specimens were randomly allocated to 1 of 3 repair techniques: Huttunen et al. (2014) (1) PARS Achilles Jig System, Nyyssönen et al. (2008) (2) Achilles Midsubstance SpeedBridge™, Schipper and Cohen (2017) (3) Dresdner Instrument and subsequently subjected to cyclic loading with 250 cycles each at 1 Hz with 4 different loading ranges (20-100 N, 20-200 N, 20-300 N, and 20-400 N). FINDINGS: After 250 cycles no significant differences in elongation were observed between PARS and Dresdner Instrument(p = 1.0). Furthermore, SpeedBridge™ repairs elongated less than either Dresdner Instrument (p = 0.0006) or PARS (p = 0.102). Main elongation (85%) occurred within the first 10 cycles with a comparable elongation in between 10 and 100 and 100-250 cycles. While all repairs withstood the first 250 cycles of cyclic loading from 20 to 100 N, only the PARS (468 ± 175) and Midsubstance SpeedBridge™ (538 ± 208) survived more cycles. Within all 3 groups suture cut out was seen to be the most common failure mechanism. INTERPRETATION: Within all groups early repair elongation was seen. While this was least obvious within the SpeedBridge™ technique, ultimate strengths of repairs (cycles to failure) were comparable across PARS and SpeedBridge™ with a decline in the Dresdner Instrument group.

The HER2 phenotype of circulating tumor cells in HER2-positive early breast cancer: A translational research project of a prospective randomized phase III trial.

BACKGROUND: HER2 is one of the predominant therapeutic targets in breast cancer. The metastatic selection process may lead to discrepancies between the HER2 status of the primary tumor and circulating tumor cells (CTCs). This study analyzed the HER2 status of CTCs in patients with HER2-positive primary breast cancer at the time of diagnosis. Aim of the study was to assess potential discordance of HER2 status between primary tumor and CTCs, as this may have important implications for the use of HER2-targeted therapy. METHODS: The number and HER2 status of CTCs out of 30ml peripheral blood were assessed in 642 patients using the CellSearch System (Janssen Diagnostics, USA). The cutoff for CTC positivity was the presence of at least 1 CTC, and the cutoff for HER2 positivity of CTCs was the presence of at least 1 CTC with a strong HER2 staining. RESULTS: 258 (40.2%) of the 642 patients were positive for CTCs (median 2; range 1-1,689). 149 (57.8%) of these 258 patients had at least 1 CTC with strong HER2 staining. The presence of HER2-positive CTCs was not associated with tumor size (p = 0.335), histopathological grading (p = 0.976), hormone receptor status (ER: p = 0.626, PR: p = 0.263) or axillary lymph node involvement (p = 0.430). Overall, 83 (32.2%) of the CTC-positive patients exclusively had CTCs with strong HER2 staining, whereas 31 (12.0%) had only CTCs with negative HER2 staining. Within-sample variation in the HER2 status of CTCs was found in 86 (57.8%) of the 149 patients with more than 1 CTC. CONCLUSION: This study demonstrated that discordance between the HER2 expression of CTCs and that of the primary tumor frequently occurs in early breast cancer. Future follow-up evaluation will assess whether this discrepancy may contribute to trastuzumab resistance.

First case of Roussoella percutanea bursitis.

Roussoella percutanea is a novel opportunistic pathogen firstly identified in 2014. It is known to cause subcutaneous infection in immunosuppressed patients. We report on the first case of R. percutanea bursitis in a renal transplant patient. We provide new data about its identification, drug susceptibility, and treatment outcome. Here we demonstrate that R. percutanea is a potential human pathogen.

Polyethylene wear particles induce TLR 2 upregulation in the synovial layer of mice.

A cellular and receptor mediated response to ultra-high-molecular-weight-polyethylene (UHMWPE) wear particles results in a release of proinflammatory cytokines and induces an inflammatory reaction causing osteolysis in total joint replacement. This investigation offers insight into the toll-like receptor (TLR) mediated activation by polyethylene wear particles in the synovial layer of mice. We hypothesized that, similar to recent in vitro results, UHMWPE particles lead to an upregulation of TLR 1 and 2 and TLR 4 in vivo in the synovial tissue of mice as well. Therefore, UHMWPE particles were generated in a common knee simulator according to the ISO standard, separated by acid digestion and determined by scanning electron microscopy. Endotoxin was removed using a method based on ultracentrifugation. A particle suspension (50 µl; 0.1 vol./vol.%) was injected into the left knee joint of female Balb/c mice (n = 8). In a control group, phosphate-buffered saline was injected into the left knee of Balb/c mice (n = 8). The mice were sacrificed after 7 days. Immunohistochemical staining was performed with TLR 1, 2 and 4 polyclonal antibodies for Balb/c mice and evaluated by light microscopy. The particle-stimulated group showed a thickened synovial layer, an increased cellular infiltration and a TLR 2-upregulation in the synovial layer compared to the control group. An increased expression of TLR 1 and TLR 4 could not be demonstrated. These results indicate a mainly TLR 2-induced inflammation to polyethylene wear debris in the synovial layer of mice.

Breast Cancer: State of the Art and New Findings.

Advances in research have a highly influential role to play in the strategy of early detection, treatment and aftercare of breast cancer and therefore everyday clinical practice. Newly-defined prognosis factors and a new form of molecular subtype classification, for example, are intended to help identify patients who will actually benefit from chemotherapy. In the field of neoadjuvant chemotherapy, the inclusion of the angiogenesis inhibitor Bevacizumab and dual antiHER2 therapy is being discussed. What's more, where defined criteria are met, even with positive sentinel lymph nodes, axillary dissection is not performed; besides bisphosphonates RANKL antibody Denosumab is now an option in the treatment of bone metastases.

Optimization of a LSO-Based Detector Module for Time-of-Flight PET.

We have explored methods for optimizing the timing resolution of an LSO-based detector module for a single-ring, "demonstration" time-of-flight PET camera. By maximizing the area that couples the scintillator to the PMT and minimizing the average path length that the scintillation photons travel, a single detector timing resolution of 218 ps fwhm is measured, which is considerably better than the ~385 ps fwhm obtained by commercial LSO or LYSO TOF detector modules. We explored different surface treatments (saw-cut, mechanically polished, and chemically etched) and reflector materials (Teflon tape, ESR, Lumirror, Melinex, white epoxy, and white paint), and found that for our geometry, a chemically etched surface had 5% better timing resolution than the saw-cut or mechanically polished surfaces, and while there was little dependence on the timing resolution between the various reflectors, white paint and white epoxy were a few percent better. Adding co-dopants to LSO shortened the decay time from 40 ns to ~30 ns but maintained the same or higher total light output. This increased the initial photoelectron rate and so improved the timing resolution by 15%. Using photomultiplier tubes with higher quantum efficiency (blue sensitivity index of 13.5 rather than 12) improved the timing resolution by an additional 5%. By choosing the optimum surface treatment (chemically etched), reflector (white paint), LSO composition (co-doped), and PMT (13.5 blue sensitivity index), the coincidence timing resolution of our detector module was reduced from 309 ps to 220 ps fwhm.

Long-term effects of language intensity in preventive messages on planned family solar protection.

A series of sun safety messages containing highly intense language and deductive logical style achieved the most immediate compliance by parents, particularly when they intended to improve protection. Inductive messages were more successful when no intentions existed (D. B. Buller, Borland, & Burgoon, 1998; D. B. Buller et al., 2000). Interviewers recontacted 568 parents during the winter following message dissemination and assessed solar protection. A 2 (language intensity) x 2 (logical style) x 3 (behavioral intention) x 2 (person) mixed-model analysis of variance showed that parents receiving high-intensity, deductive messages reported the most improved solar protection and improvement was greatest when parents intended to improve protection. Over the long term, high language intensity may reinforce decisions to take preventive action and does not appear to provoke psychological reactance or resistance to these highly directive messages.

Scintillation crystals for PET.

In PET, inorganic scintillator crystals are used to record gamma-rays produced by the annihilation of positrons emitted by injected tracers. The ultimate performance of the camera is strongly tied to both the physical and scintillation properties of the crystals. For this reason, researchers have investigated virtually all known scintillator crystals for possible use in PET. Despite this massive research effort, only a few different scintillators have been found that have a suitable combination of characteristics, and only 2 (thallium-doped sodium iodide and bismuth germanate) have found widespread use. A recently developed scintillator crystal, cerium-doped lutetium oxyorthosilicate, appears to surpass all previously used materials in most respects and promises to be the basis for the next generation of PET cameras.

Using language intensity to increase the success of a family intervention to protect children from ultraviolet radiation: predictions from language expectancy theory.

BACKGROUND: Even though people are informed about skin cancer prevention, they do not always comply with prevention advice. From Language Expectancy Theory, it was predicted that messages with high language intensity would improve compliance with sun safety recommendations and that this effect would be enhanced with deductive argument style. METHODS: Parents (N = 841) from a pediatric clinic and elementary schools received sun safety messages (newsletters, brochures, tip cards) by mail that varied in language intensity and logical style. Effects on attitudes and behavior were tested in a pretest-posttest factorial design. RESULTS: As hypothesized, parents receiving messages with high- as opposed to low-intensity language complied more with sun safety advice. Messages with highly intense language were more persuasive when the arguments were formatted in a deductive style; low language intensity was more persuasive in inductively styled messages. CONCLUSIONS: By carefully adjusting messages features, health professionals can obtain further compliance beyond that produced by educating people about health risks and creating favorable attitudes and self-efficacy expectations. Highly intense language may be a good general strategy in prevention messages and works better when conclusions and recommendations are offered explicitly to recipients, especially when advice is aimed at reducing their personal risk.

Thermoluminescent determination of prehistoric heat treatment of chert artifacts.

In recent years archeologists have become interested in the extent to which prehistoric peoples heat-treated chert prior to shaping it into tools. Thermoluminescent determination of the radiation dose accumulated by an artifact since it was formed or last heated provides a simple, reliable test for such heat treatment. This test can be applied to single artifacts without the need for raw source material for comparison. Results on 25 artifacts from four sites indicate that, for many chert sources, color and luster are not useful indicators of heat treatment by prehistoric peoples.