Discovery of TRPA1 Antagonist : Derisking Preclinical Toxicity and Aldehyde Oxidase Metabolism with a Potential First-in-Class Therapy for Respiratory Disease

Transient receptor potential ankyrin 1 (TRPA1) is a nonselective calcium ion channel highly expressed in the primary sensory neurons, functioning as a polymodal sensor for exogenous and endogenous stimuli, and has been implicated in neuropathic pain and respiratory disease. Herein, we describe the optimization of potent, selective, and orally bioavailable TRPA1 small molecule antagonists with strong in vivo target engagement in rodent models. Several lead molecules in preclinical single- and short-term repeat-dose toxicity studies exhibited profound prolongation of coagulation parameters. Based on a thorough investigative toxicology and clinical pathology analysis, anticoagulation effects in vivo are hypothesized to be manifested by a metabolite─generated by aldehyde oxidase (AO)─possessing a similar pharmacophore to known anticoagulants (i.e., coumarins, indandiones). Further optimization to block AO-mediated metabolism yielded compounds that ameliorated coagulation effects in vivo, resulting in the discovery and advancement of clinical candidate GDC-6599, currently in Phase II clinical trials for respiratory indications.

New Constraint on the Local Relic Neutrino Background Overdensity with the First KATRIN Data Runs

We report on the direct search for cosmic relic neutrinos using data acquired during the first two science campaigns of the KATRIN experiment in 2019. Beta-decay electrons from a high-purity molecular tritium gas source are analyzed by a high-resolution MAC-E filter around the end point at 18.57 keV. The analysis is sensitive to a local relic neutrino overdensity ratio of η<9.7×10^{10}/α (1.1×10^{11}/α) at a 90% (95%) confidence level with α=1 (0.5) for Majorana (Dirac) neutrinos. A fit of the integrated electron spectrum over a narrow interval around the end point accounting for relic neutrino captures in the tritium source reveals no significant overdensity. This work improves the results obtained by the previous neutrino mass experiments at Los Alamos and Troitsk. We furthermore update the projected final sensitivity of the KATRIN experiment to η<1×10^{10}/α at 90% confidence level, by relying on updated operational conditions.

Effect of molecular size on interstitial pharmacokinetics and tissue catabolism of antibodies

Advances in antibody engineering have enabled the construction of novel molecular formats in diverse shapes and sizes, providing new opportunities for biologic therapies and expanding the need to understand how various structural aspects affect their distribution properties. To assess the effect of antibody size on systemic pharmacokinetics (PK) and tissue distribution with or without neonatal Fc receptor (FcRn) binding, we evaluated a series of non-mouse-binding anti-glycoprotein D monoclonal antibody formats, including IgG [~150 kDa], one-armed IgG [~100 kDa], IgG-HAHQ (attenuated FcRn binding) [~150 kDa], F(ab')₂ [~100 kDa], and F(ab) [~50 kDa]. Tissue-specific concentration-time profiles were corrected for blood content based on vascular volumes and normalized based on interstitial volumes to allow estimation of interstitial concentrations and interstitial:serum concentration ratios. Blood correction demonstrated that the contribution of circulating antibody on total uptake was greatest at early time points and for highly vascularized tissues. Tissue interstitial PK largely mirrored serum exposure profiles. Similar interstitial:serum ratios were obtained for the two FcRn-binding molecules, IgG and one-armed IgG, which reached pseudo-steady-state kinetics in most tissues. For non-FcRn-binding molecules, interstitial:serum ratios changed over time, suggesting that these molecules did not reach steady-state kinetics during the study. Furthermore, concentration-time profiles of both intact and catabolized molecule were measured by a dual tracer approach, enabling quantification of tissue catabolism and demonstrating that catabolism levels were highest for IgG-HAHQ. Overall, these data sets provide insight into factors affecting preclinical distribution and may be useful in estimating interstitial concentrations and/or catabolism in human tissues.

Sialadenitis as chickenpox complication in a 6-year-old girl

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In the 6.year old girl with chickenpox we diagnosed an typical complication in the shape of sialadenitis (especially submaxillitis).

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Within the last twenty years, only in one child the relationship between sialadenitis and varicella-zoster virus infection has been suggested.

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Our observation has important clinical significance.

Chickenpox is considered as a mild disease, but sometimes it is associated with complications. Among them sialadenitis is mentioned sporadically. We describe a case of the 6-year-old girl suffering from complicated chickenpox. On the basis of clinical data and ultrasound image we diagnosed in her inflammation of both submandibular glands. Moreover, the ultrasound image suggested possibility of an inflammation developing in the left parotid gland.

Physico-chemical investigation of endodontic sealers exposed to simulated intracanal heat application: epoxy resins and zinc oxide-eugenols

AIM

To gain information in a laboratory setting about the effect of thermal treatment of epoxy resin-based and zinc oxide-eugenol-based sealers.

METHODOLOGY

AH Plus and Pulp Canal Sealer (PCS) were exposed to thermal treatment at 37, 47, 57, 67, 77, 87 and 97 °C for 30 s. According to clinically relevant considerations, intracanal sealer temperature is likely not to exceed 60 °C during warm vertical root canal filling. Heat application is recommended for less than 30 s during continuous wave technique, but might exceed this threshold in complex cases. Furthermore, heat treatment at 97 °C was performed for 60 and 180 s to simulate inappropriate implementation of warm vertical filling techniques. Specimens were heated inside 2-mL plastic tubes in a thermo-controlled water bath until the temperatures were reached and kept at this temperature for the determined period of time. Afterwards, specimens were cooled to body temperature and physical properties (setting time, flow, film thickness according to ISO 6876) were assessed. Chemical properties (Fourier transformed infrared spectroscopy) were assessed after complete setting of the specimens in an incubator at 37 °C and 100% humidity. Statistical analysis of physical properties was performed using Kruskal-Wallis test (P = 0.05).

RESULTS

The setting time of AH Plus and PCS decreased when temperature and duration of heat application increased. Whilst the setting time of AH Plus decreased from 622 min at 20 °C (for 30 s) to 381 min at 97 °C (for 180 s; P < 0.05), heat treatment of PCS at 97 °C for 180 s led to an immediate setting of the material. From 20 °C (for 30 s) to 97 °C (for 30 s), the setting time of PCS decreased from 80.1 to 41.0 h (P < 0.05). Film thickness and flow were not relevantly influenced by thermal treatment except for PCS at 97 °C for 180 s. FT-IR spectroscopy did not reveal any chemical changes of either sealer after thermal treatment.

CONCLUSIONS

Thermal treatment simulating clinically relevant temperature levels and heating times did not lead to any substantial physical or chemical changes at all temperature levels when heating did not exceed 60 s. AH Plus and Pulp Canal Sealer can be considered suitable for warm root filling techniques.

Improved Upper Limit on the Neutrino Mass from a Direct Kinematic Method by KATRIN

We report on the neutrino mass measurement result from the first four-week science run of the Karlsruhe Tritium Neutrino experiment KATRIN in spring 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are energy analyzed by a high-resolution MAC-E filter. A fit of the integrated electron spectrum over a narrow interval around the kinematic end point at 18.57 keV gives an effective neutrino mass square value of (-1.0_{-1.1}^{+0.9})  eV^{2}. From this, we derive an upper limit of 1.1 eV (90% confidence level) on the absolute mass scale of neutrinos. This value coincides with the KATRIN sensitivity. It improves upon previous mass limits from kinematic measurements by almost a factor of 2 and provides model-independent input to cosmological studies of structure formation.

Atomic resolution elemental mapping using energy-filtered imaging scanning transmission electron microscopy with chromatic aberration correction

This paper addresses a novel approach to atomic resolution elemental mapping, demonstrating a method that produces elemental maps with a similar resolution to the established method of electron energy-loss spectroscopy in scanning transmission electron microscopy. Dubbed energy-filtered imaging scanning transmission electron microscopy (EFISTEM) this mode of imaging is, by the quantum mechanical principle of reciprocity, equivalent to tilting the probe in energy-filtered transmission electron microscopy (EFTEM) through a cone and incoherently averaging the results. In this paper we present a proof-of-principle EFISTEM experimental study on strontium titanate. The present approach, made possible by chromatic aberration correction, has the advantage that it provides elemental maps which are immune to spatial incoherence in the electron source, coherent aberrations in the probe-forming lens and probe jitter. The veracity of the experiment is supported by quantum mechanical image simulations, which provide an insight into the image-forming process. Elemental maps obtained in EFTEM suffer from the effect known as preservation of elastic contrast, which, for example, can lead to a given atomic species appearing to be in atomic columns where it is not to be found. EFISTEM very substantially reduces the preservation of elastic contrast and yields images which show stability of contrast with changing thickness. The experimental application is demonstrated in a proof-of-principle study on strontium titanate.

Canal cleanliness using different irrigation activation systems: a SEM evaluation

OBJECTIVES

The purpose of this study was to assess the efficacy of different final irrigation activation methods in removing debris and smear layer in the apical, middle, and coronal portion of straight root canals.

MATERIAL AND METHODS

Straight root canals of 58 freshly extracted mandibular premolars were used. Root canals were prepared to size 40.06. Irrigation was performed using 3% sodium hypochlorite. Samples were divided into four equal groups (n = 12) according to the irrigation activation techniques: (A) manual irrigation (MI), (B) EndoActivator (EA) (Dentsply Maillefer, Ballaigues, Switzerland), (C) sonic activation EDDY (EDDY; VDW, Munich, Germany), and (D) passive ultrasonic irrigation (PUI). Ten teeth served as negative controls. Roots were split longitudinally, and the canal walls were subjected to scanning electron microscopy. The presence of debris and smear layer at coronal, middle, and apical levels were evaluated using a 5-point scoring system and statistically analyzed using Kruskal-Wallis and chi-square tests.

RESULTS

Canal cleanliness decreased from coronal to apical (P = 0.035). Significantly more debris was removed with EA, EDDY, and PUI compared to MI (P < 0.001; total values), but no differences were observed in the different portions of the root canals (P > 0.05). Smear layer removal with PUI, EA, and EDDY was not significantly different (P > 0.05), but only EDDY and PUI were superior to MI (P < 0.01).

CONCLUSION

All activation methods created nearly debris-free canal walls and were superior compared to manual irrigation (P < 0.001). EDDY and PUI also showed significantly better smear layer scores compared to manual irrigation.

CLINICAL RELEVANCE

The sonic activation system EDDY performed equally as well as PUI, and both methods were significantly superior compared with manual irrigation in straight root canals with regard to debris and smear layer removal.

Evaluating the Use of Antibody Variable Region (Fv) Charge as a Risk Assessment Tool for Predicting Typical Cynomolgus Monkey Pharmacokinetics

The pharmacokinetic (PK) behavior of monoclonal antibodies in cynomolgus monkeys (cynos) is generally translatable to that in humans. Unfortunately, about 39% of the antibodies evaluated for PKs in cynos have fast nonspecific (or non-target-mediated) clearance (in-house data). An empirical model relating variable region (Fv) charge and hydrophobicity to cyno nonspecific clearance was developed to gauge the risk an antibody would have for fast nonspecific clearance in the monkey. The purpose of this study was to evaluate the predictability of this empirical model on cyno nonspecific clearance with antibodies specifically engineered to have either high or low Fv charge. These amino acid changes were made in the Fv region of two test antibodies, humAb4D5-8 and anti-lymphotoxin α. The humAb4D5-8 has a typical nonspecific clearance in cynos, and by making it more positively charged, the antibody acquires fast nonspecific clearance, and making it less positively charged did not impact its clearance. Anti-lymphotoxin α has fast nonspecific clearance in cynos, and making it more positively charged caused it to clear even faster, whereas making it less positively charged caused it to clear slower and within the typical range. These trends in clearance were also observed in two other preclinical species, mice and rats. The effect of modifying Fv charge on subcutaneous bioavailability was also examined, and in general bioavailability was inversely related to the direction of the Fv charge change. Thus, modifying Fv charge appears to impact antibody PKs, and the changes tended to correlate with those predicted by the empirical model.

Mycotoxins as antagonistic or supporting agents in the interaction between phytopathogenic Fusarium and Alternaria fungi

The role of mycotoxins in the microbial competition in an ecosystem or on the same host plant is still unclear. Therefore, a laboratory study was conducted to evaluate the influence of mycotoxins on growth and mycotoxin production of Fusarium and Alternaria fungi. Fusarium culmorum Fc13, Fusarium graminearum Fg23 and two Alternaria tenuissima isolates (At18 and At220) were incubated on wheat kernels supplemented with alternariol (AOH), tetramic acid derivates (TeA), deoxynivalenol (DON) and zearalenone (ZEA) in an in vitro test system. Fungal biomass was quantified by determining ergosterol content. Three Fusarium toxins (DON, nivalenol and ZEA) and three Alternaria toxins (AOH, alternariol methyl ether (AME) and altenuene) were analysed by HPLC-MS/MS. If Alternaria strains grew in wheat kernels spiked with Fusarium mycotoxins, their growth rates were moderately increased, their AOH and AME production was enhanced and they were simultaneously capable of degrading the Fusarium mycotoxins DON and ZEA. In contrast, both Fusarium strains behaved quite differently. The growth rate of Fc13 was not distinctly influenced, while Fg23 increased its growth in wheat kernels spiked with AOH. TeA depressed the ergosterol content in Fc13 as well as in Fg23. The DON production of Fc13 was slightly depressed, whereas the ZEA production was significantly increased. In contrast, Fg23 restricted its ZEA production. Both Fusarium strains were not capable of degrading the Alternaria mycotoxin AOH. Mycotoxins might play an important role in the interfungal competitive processes. They influence growth rates and mycotoxin production of the antagonistic combatants. The observed effects between phytopathogenic Alternaria and Fusarium strains and their mycotoxins aid the understanding of the complexity of microbial competitive behaviour in natural environments.

Electron-Diffraction Study on an Amorphous Al-V Alloy Produced by Electron Irradiation of Quasicrystalline Al-16 at-%V

Quasicrystalline Al-16 at-%V was transformed to the amorphous state by low-temperature electron irradiation in a high-voltage electron microscope. Electron diffraction experiments were carried out in the amorphous state and in the crystalline state obtained after subsequent heat treatment. From the results the total structure factor was determined. The pair correlation function was calculated which yields the radii of the different coordination spheres and the total coordination number. The results are discussed in terms of current topological models of the structure of metallic glasses.

Abstract 3908: Generation of invasive breast cancer cell lines for in vivo imaging

Whole animal non-invasive imaging contributes significantly to understand tumor behavior. It also plays a critical role in drug discovery and development. Optical imaging is convenient because it does not require radioactive materials for imaging. Especially in preclinical applications, optical imaging can be a very useful tool because genetic modification is feasible. The most popular optical imaging is using bioluminescence. We introduced various cancer cell lines that express firefly luciferase. These cells have stable expression of light emission for prolonged cell culture situation. This enables for researchers to implant the cells into animals and to monitor tumor development and metastasis. In addition, these tumor cells can be detected using fluorescent agents that target tumor cells. As a consequence, one can co-register both bioluminescent and fluorescent images. Cells also can be labeled both bioluminescent and fluorescent markers such as luciferases and fluorescent proteins. Although there are many different types of cell lines available for different tumor types, studying metastasis can be challenging. That is mainly because most popular cell lines show delayed metastasis when implanted in the animal. To expedite the metastasis, intravenous injection or intracardiac injection is performed to generate secondary tumors in the animal. However, these methods do not represent true metastasis from originated organs. One of the most popular breast cancer cell line is MDA-MB-231. When these cells are implanted into mammary fat pads of female nude mice, it typically takes more than 90 days to detect metastasis in the secondary sites. Therefore, to study the tumor behavior or to examine the drug efficacy, one should wait for a long time to see the metastasis. Here, we generated tumor cell lines that were derived from MDA-MB-231 originated cells. We took MDA-MB-231 cells that were labeled with either luciferase (MDA-MB-231-luc2) or luciferase & tdTomato fluorescent protein (MDA-MB-231-luc2-tdTomato). These cells were implanted into mammary fat pads of nude mice and secondary tumors were isolated from lymph nodes. Tissues were dissociated to single cells and clonal cell lines were established (MDA-MB-231-luc2-LN and MDA-MB-231-luc2-tdTomato-LN). The growth patterns of these cells were compared to their corresponding parental cells. To find out the metastasis patterns of these cells, we implanted new cell lines orthotopically into nude mice. Our results showed that these cell lines showed faster metastases than parental cell lines. Moreover, we examined biomarker expression patterns with multiplexing multispectral microscopy. These cells can be used to study tumor metastasis and drug discovery using non-invasive in vivo imaging.

Citation Format: Jae Beom Kim, Kenneth Wong, Konnie Urban. Generation of invasive breast cancer cell lines for in vivo imaging. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3908. doi:10.1158/1538-7445.AM2013-3908

Abstract 4292: In vivo and in vitro imaging of Cyclooxygenase-2 in tumor

Cyclooxygenase-2 (Cox-2) is a biomarker for tumor progression and inflammatory diseases. It is known that normal tissues express minimal amounts of Cox-2 proteins while inflammatory and malignant tumor cells express high levels. Thus, inhibition of Cox-2 is a strategy in the treatment of tumor progression and inflammatory diseases. Recently, many different kinds of molecular imaging reagents for Cox-2 have been developed. Among them, an indomethacin-based Cox-2 probe, fluorocoxib, has been shown to bind to Cox-2 in vitro and in vivo. The binding specificity to Cox-2 was shown using cell culture and tumor xenograph models. In our present study, in order to optimize fluorocoxib imaging conditions, we utilized HCT116 and HT29 cells as low and high Cox-2 expressers, respectively. First, cultured cells were grown overnight on cover slips. Cells were then fixed with paraformaldehyde and incubated with fluorocoxib probe. Multispectral images were taken using a camera equipped with liquid crystal tunable filters. Spectral unmixing was applied to these images to enhance fluorocoxib signals. Our results indicate that HCT116 cells express fair amounts of Cox-2 protein. We also transplanted HCT116 and HT29 cells into the flank regions of nu/nu mice subcutaneously. After tumors grew to sufficient size (∼100 mm3) we injected fluorocoxib intravenously and monitored probe binding to the tumors. Whole animal in vivo imaging indicated that fluorocoxib binds to HT29 tumors after 3 hours. All the probes were eliminated from the animals by 24 hours. On the other hand, HCT116 tumors did not show strong binding of fluorocoxib as expected. However, HCT116 tumors did show some weak binding at the 3 and 6 hr time points. Once there was no longer any probe detected in vivo, we dissected the primary tumors from the HCT116 and HT29 implantations. Tissue sections were made with paraffin embedded tumors. After deparaffinization, tissue sections were incubated with fluorocoxib and fluorescent images were taken using multispectral imaging technology. Spectral unmixing data confirmed that HCT116 tumor sections showed fair amounts of Cox-2 probe expression. The amount of binding was also quantitated using a corresponding software package. Our results demonstrated that fluorescent biomarker probes can be imaged in vitro and in vivo non-invasively. Furthermore, we showed that the expression level can be quantitated using spectral unmixing imaging technology.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4292. doi:1538-7445.AM2012-4292

Our eight-year experience with breast reconstruction using abdominal advancement flap (207 reconstructions)

There are many possibilities for breast reconstruction after mastectomy. The use of abdominal advancement flap in combination with silicone implant is among the less commonly used methods, although it is simple, fast and leads to excellent results. We started to use this technique at our department eight years ago. Since then we have performed 207 breast reconstructions using abdominal advancement flap in combination with silicone implants. We performed follow-up checks on the patients for between one and six years.

[Bone healing capacity in patients undergoing total hip arthroplasty]

PURPOSE OF THE STUDY

To identify some characteristics of bone repair capacity in elderly patients who undergo total hip arthroplasty, which requires good healing ability of bone for implant osteointegration and bone defect repair, particularly if revision arthroplasty is necessary.

MATERIAL AND METHODS

In a group of 27 patients (mean age, 70 ± 7 years; range, 60 to 81 years) a coincidence of osteoarthritis and osteopenia/ osteoporosis was assessed, and mesenchymal stem cells (MSC) were isolated and their numbers, viability and proliferative capacity were evaluated. The MSC populations were examined for their behaviour on bone tissue scaffolds used in orthopaedic surgery for treatment of bone lesions. Each patient underwent bone densitometry examination before total hip arthroplasty. Bone marrow was harvested intra-operatively from the trochanteric region of the femur. From a portion of bone marrow, MSCs were isolated and cultured, and a mononuclear cell concentrate was obtained. Either whole bone marrow or a mononuclear cell concentrate was applied to selected matrices (allograft, demineralised bone matrix, porous beta-tricalcium phosphate (-TCP), pressed hydroxyapatite or calcium sulphate). The production of new collagen and extracellular mineralized matrix were first assessed in expansion medium and, when the production was low, differentiation medium was used.

RESULTS

A coincidence of osteoarthritis and osteopenia/osteoporosis was found in 50% of the patients. All were women with a low body mass index and had been post-menopausal for an average of 23 years. The isolated MSCs contained a high percentage of viable cells (mean, 95%). The mesenchymal cells of patients with osteopenia, as compared with those having normal bone density, showed markedly lower numbers of fibroblastic colony forming units (CFU-F) per ml and had a lower proliferative capacity because the population doubling time during the first four passages was much longer. Of the scaffolds tested, allografts showed the most marked collagen and extracellular mineralized matrix production in expansion medium with either whole bone marrow or a monocyte concentrate; porous -TCP was the best of bone graft substitutes in collagen and extracellular mineralized matrix production by both whole bone marrow and a monocyte concentrate, but this was only in differential medium.

DISCUSSION

The coincidence of ostearthritis with osteopenia/osteoporosis was found in a higher number of our patients than is reported in the literature. Also, a lower MSC proliferative capacity and a low number of CFU-F/ml in the patients with low bone density were interesting findings. Better bone regeneration would generally be achieved with higher MSC numbers and the use of growth factors for stimulation of osteoinduction and angiogenesis. Bone marrow harvesting for MSC isolation, cultivation and subsequent transplantation is currently feasible only in an experiment. A bone marrow aspirate can be applied, but it may not provide a sufficient number of MSCs. In addition to autologous bone grafts, the best collagen production was on allografts. In bone graft substitutes, the porous structure played an important role because on a non-porous material (calcium sulphate) the formation of collagen was very low. There was no difference in collagen and extracellular mineralized matrix production between whole bone marrow and monocyte concentrates.

CONCLUSIONS

Elderly patients have reduced bone healing capacity also because of osteopenia/osteoporosis that occurs more often than it is generally diagnosed, including its coincidence with osteoarthritis. The mesenchymal stem cells isolated from osteopenic bone give a lower number of CFU-F/ml and have a lower proliferative capacity. Of the matrices for new bone formation, allografts showed the best results because collagen was produced already in expansion medium. Of the graft substitutes, porous -TCP was the best, but with collagen production in differential medium. The use of bone marrow aspirate is currently a method of choice in order to increase MSC numbers at the site of bone healing. The use of growth factors is an expensive treatment. To achieve the goal of reliable promotion of osteogenesis with cultured MSC transplantation and use of composite materials with pro-osteogenic and pro-angiogenic factors will still require many experimental and clinical studies.

Abstract 5228: Multi-modal in vivo imaging of breast cancer cells expressing dual reporters

We previously engineered tumor cell lines with bioluminescent markers and fluorescent proteins for whole animal imaging. In addition to conventional non-invasive tumor growth detection, these cells when harvested from animals can also be used to analyze cell-cell interactions by immunohistochemistry. Moreover, fluorescent cells can be isolated using fluorescent activated cell sorting (FACS) for gene expression profiling. In this study, we used a mouse mammary gland tumor cell line 4T1 that was labeled with firefly luciferase and tdTomato fluorescent protein (4T1-luc2-tdTomato). The generated cell line was tested for in vitro signal stability with respect to bioluminescence and fluorescence prior to injection into the animals. Tumor cells were implanted subcutaneously and monitored for tumor development by acquisition of bioluminescent and fluorescent images. In a separate study, 4T1-luc2-tdTomato cells were implanted orthotopically into mammary fat pads. Tumor growth was monitored and signals from the implantation sites were reconstructed into three dimensional images. In order to non-invasively detect bone metastases by 4T1-luc2-tdTomato cells, we applied both microCT and optical imaging. For this, an interchangeable imaging platform between an optical imager and microCT machine was developed. 4T1-luc2-tdTomato cells were injected into nu/nu mice by intracardiac injection. Bioluminescent imaging was performed immediately to verify the injection of cells into the left ventricle. Fluorescent signals were not detected, likely due to the small number of cells in the secondary tumor sites. Animals demonstrating substantial whole body bioluminescence were selected for further monitoring until post injection day 9. We found that bioluminescent signals were located in the knee joint regions. For these animals, bioluminescent and X-ray images were also taken without changing the positions of the animals using the interchangeable platform. Bioluminescent images in the knee joints were reconstructed using a diffused luminescence imaging tomography algorithm. These images were then co-registered with microCT images. The results showed that bioluminescent signals were colocalized within the joint area obtained by microCT. Moreover, high resolution images of the joints from these mice revealed bone erosion in the tibia induced by 4T1-luc2-tdTomato cells. These findings demonstrate that multimodal imaging can pinpoint the tumor lesions non-invasively. In addition, low dose microCT imaging can be used to acquire high resolution skeletal images longitudinally without inducing adverse effects on the animals.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 5228. doi:10.1158/1538-7445.AM2011-5228

Grain Boundaries In Diamond Films On Si(001)

Grain boundaries in [001]-oriented diamond films deposited on Si(001) by microwave-assisted chemical vapor deposition have been investigated in plan-view and cross-section samples using high-resolution electron microscopy. The poly-crystalline diamond films used in this study had large fractions of [001]-oriented grains with typical lateral dimensions of 2 μm at film thicknesses beyond 10 μm. Grains with growth orientations near (001) exhibit generally small-angle orientation deviations between their crystal lattices. Small-angle grain boundaries of symmetric and asymmetric geometry with misorientation angles below 15° are investigated in both [110]- and [001]-directions. It is found that the structures of such small-angle grain boundaries can be described by a dislocation model. These grain boundaries are on average parallel to the {110}-plane and contain in many cases micro-facets parallel to {lll}-planes. Large-angle grain boundaries with tilt angles up to 40° are also observed in interconnected films of smaller thickness. In all cases structural units with large open volumes and additional second phases are not found at the grain boundaries.

Quantitative HRTEM investigation of an obtuse angle dislocation reaction in gold with a CScorrected field emission microscope

We investigate quantitatively the non periodic arrangement of atom columns surrounding an obtuse angle dislocation reaction in gold utilizing a CM200 FEG instrument equipped with a spherical aberration corrector. The in-plane component of the Burgers vector of the observed stair-rod dislocation is ⅙ [110]. Column positions are determined from single lattice images and compared with those from a reconstructed electron exit wave. We find that absolute position measurements of 1–3 pm require knowledge of the defocus to better than 1 nm which can be achieved by a reconstruction of the exit-plane wave. In contrast, a defocus value of 8.9 nm already leads to apparent displacements as large as 35 pm if single lattice images are considered. Such discrepancies are either caused by residual lens aberrations or by the superposition of delocalization effects at interfaces caused by defocusing of the objective lens. Commonly, however, only relative displacements are of interest. In this case the CS corrector improves the interpretability of single defocused lattice images with a remarkable signal to noise ratio which is advantageous for in-situ experiments. As an example for analyzing in-situ experiments we determine displacements recorded in a time resolved experiment of radiation induced atom motion on surfaces.

[Valgus high tibial osteotomy - long-term results]

PURPOSE OF THE STUDY

The aim of the study was to evaluate the long-term results in a group of patients treated by proximal tibial valgus osteotomy.

MATERIAL

A group of 92 high tibial osteotomies performed in the 1985/1994 period were evaluated. All were indicated for primary osteoarthritis. Closing wedge osteotomy was the technique used. Staple-fixed osteotomy was immobilised in a plaster cast for 6 weeks in 44 cases. Osteotomy fixed with a plate in 35 or with a cerclage in 13 cases was immobilised for two weeks.

METHODS

Recurrent intensive pain and walking problems were regarded as a termination of the favourable effect of osteotomy. This was evaluated by the Kaplan-Meier survival analysis. The tibio-femoral angle 5 to 10 degrees of valgus was considered as an optimal deformity correction. The results were compared in relation to complications, correction, duration of immobilisation and patient age.

RESULTS

The mean age of the patients was 59.8 ± 8.7 years (range, 42 to 78). During surgery, medial unicompartmental arthritis, grade II or higher, was recorded in 59 patients (64.1%) and multicompartmental knee arthritis was found in 66 patients (71.7%). The absence of noticeable problems was reported by 80.4% of the patients at 10 years and by 30.4 % at 15 years after osteotomy. Surgery decreased the range of motion from 100 ± 6.9 to 94.5 ± 17.7 degrees flexion (p = 0.04). Poor correction and post-operative complications were found in 21 patients (22.8 %) who also experienced significantly worse outcomes (p = 0.003). Good results after 10 and 15 years were reported by 47.6% and 14.3% of the patients, respectively. Of 71 patients (77.2%) who had good correction and surgery without complications, the osteotomy showed a good effect in 90.1% at 10 post-operative years and in 35.2% at 15 years. A longer immobilisation resulted in significantly worse results (p = 0.04) and a restricted range of motion (p = 0.02). The patients younger than 60 years achieved better results than the elderly patients (p = 0.38), but the difference was not significant.

DISCUSSION

Good results were recorded up to 10 years after osteotomy, although some patients had had worse arthritis than recommended for this procedure. Inadequate correction and complications deteriorated the effect of osteotomy. With the opening wedge technique it is easier to achieve good correction, and stable fixation allows for active physical therapy. Better long-lasting results are achieved with total knee arthroplasty (TKA). However, in young active adults TKA can fail prematurely. Osteotomy can postpone the necessity of this implantation. If TKA is performed after osteotomy, functional outcomes are similar to those after primary implantation.

CONCLUSIONS

Corrective osteotomy is an effective method in patients below 60 years who have an early-stage osteoarthritis of the knee with axial mal-alignment. If the tibio-femoral angle is over-corrected to more than 10 degrees valgus, patelo-femoral pain will ensue. Post-operative active physical therapy is necessary. After bone healing, implants must be removed. Corrective osteotomy has not been overcome by the development of joint replacement techniques, but both methods are complementary in the treatment of osteoarthritis.

[Venous thromboembolism prophylaxis after total hip arthroplasty]

PURPOSE OF THE STUDY The authors compare the frequency of thromboembolic disease in the patients receiving prophylactic therapy for 10 days with that in the patients having a prolonged course of preventive treatment recommended for up to 35 days after total hip arthroplasty (THA). MATERIAL The group first evaluated comprised patients undergoing total hip replacement in 2005 and 2006 when enoxaparin was administered for 10 days after surgery. Patients with revision THA were not included. The other group included patients operated on in 2008 who received preventive treatment for 35 post-operative days either with enoxaparin for the whole time, or with enoxaparin for 10 days of hospital stay and then warfarin up to the 35th day after surgery. Patients under going revision THA and those taking other prophylactic agents were not evaluated. METHODS The evaluation of the 2005/6 group included retrospective reviews of medical records, questionnaires sent to the patients and information received from their general practitioners. The 2008 group assessment was based on the information obtained at the patient's follow-up visit at 3 months and completed with data from the questionnaires and medical notes. We focused on the records of distal or proximal deep vein thrombosis in lower extremities and of pulmonary embolism including cases with a fatal outcome. Complications associated with pharmacological prevention were also recorded. RESULTS In the 2005/6 group including 478 patients with an average age of 67.2 years, 23 (4.8 %) patients developed thrombo- embolic disease within 3 months of surgery, six patients had pulmonary embolism of which two of them died. The thromboembolic complication developed at a median of 30.5 post-operative days, i.e., after patient discharge from hospital. In the 2008 group comprising 289 patients with an average age of 63.8 years, three patients (1 %) developed thromboembolic disease within 3 months of surgery. Of them, one woman had deep vein thrombosis in relation to a high factor VIII level; and one developed pulmonary embolism with no fatal outcome. Only the minority of patients (6.9 %) continued enoxaparin therapy, the majority (93.1 %) preferred conversion to warfarin after discharge from hospital. Of the total number of 289 patients evaluated, complications associated with prophylactic treatment were recorded in 52 patients (18 %), name- ly, in 35 patients (12.1 %) it was difficult to establish the correct dosage of warfarin, in 13 patients (4.5 %) warfarin caused minor bleeding or dyspepsia and in 4 patients (1.4 %) major bleeding was recorded. DISCUSSION In our study the patients receiving a 10-day prophylactic therapy showed a slightly higher occurrence of thromboembolic disease within 3 months of THA surgery (4.8 %) than the patients reported by Eikelboom et al. (4.3 %). The results of prolonged prophylactic treatment for at least 35 days were similar, thromboembolic disease was found in 1 % of the patients. The development of thromboembolic event was recorded in our study at a median of 30.5 post-operative days, as compared with a median of 17 days in the study by Liebermann et al. In both studies, most of the thromboembolic complications developed after the patients had been discharged from hospital. The majority of patients chose warfarin for prolonged preventive treatment. There was a high complication rate (18 %) due to not finding the correct warfarin dosage or because of its overdose CONCLUSIONS Patients undergoing THA are at high risk of developing deep vein thrombosis. The risk can be markedly reduced by prolonged pharmacological ophylaxis It is recommended that the use of warfarin for this prolonged therapy should be care- fully considered, because its optimal dose is difficult to establish and its overdose may cause serious complications.

Abstract 5228: Bioluminescent reporter assays to identify signaling pathways in vivo

Whole animal optical imaging provides new ways to detect tumor cells and other biological activities in the system. Bioluminescent imaging has advantages over fluorescent imaging since animal tissues have less autoluminescence. Due to high signal to background ratio, bioluminescent imaging can detect subtle changes of light emission in the animals. Luciferases are the most popular enzymes for optical imaging. Lights are produced by enzymatic reactions in the presence of substrates. Commonly used luciferases were cloned from firefly (Photinus pyralis) and Sea Pansy (Renilla reniformis). Firefly and Renilla luciferase uses D-luciferin and coelenterazine as a substrate, respectively. Since these luciferases use different kinds of substrates, they can be used in a reporter assay simultaneously. Bioluminescent reporter assays can be achieved by conjugating transcription factor responding elements and a luciferase reporter gene. Upon signals from the outside of the cells, luciferase expression can be regulated. Using multiple responding elements for unique transcription factors, one can identify signaling pathways that are responsive to drug treatments. We have tested 10 different lentivirus reporters that carry destabilized firefly luciferase along with basal promoter element joined to tandem repeats of distinct transcription responding element. PC3M human prostate cancer cells were permanently transfected and stable cell lines were generated. As a control, constitutively active Renilla luciferase reporter was co-transfected to each reporter line. In order to identify signaling pathways that are responding to drug treatment, we plated equal number of reporter cells in well plates and treated cells with various compounds. Cisplatin, lipopolysaccaride (LPS), Paclitaxel, PMA, SB203580 or PD98059 was used for different duration. Bioluminescent images were taken at multiple time points and light emissions were quantitated. Among the compound tested, LPS generated more than 50 fold increase of bioluminescence in NF-kB luciferase (NFkB-luc) reporter cell line in vitro. In addition, the assay showed dose-dependent response. Renilla luciferase activities remained same in all reporter cell lines. To validate in vivo response, PC3M NFkB-luc cells were implanted into male nu/nu mice subcutaneously. As controls, we also implanted a non-responding reporter upon LPS treatment (TGFb-luc) and negative control without responding elements (Neg-luc). Animals were administered with LPS and in vivo bioluminescence images were taken using a cooled CCD camera. Our results showed that animals implanted with NFkB-luc mice showed 6 fold increase of luciferase activity while TGFb-luc or Neg-luc implanted animals showed little change in luciferase activity. Present study demonstrates that bioluminescent reporter assays can be applied to elucidate the mode of action of a drug.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5228.

Non-invasive detection of a small number of bioluminescent cancer cells in vivo

Early detection of tumors can significantly improve the outcome of tumor treatment. One of the most frequently asked questions in cancer imaging is how many cells can be detected non-invasively in a live animal. Although many factors limit such detection, increasing the light emission from cells is one of the most effective ways of overcoming these limitations. Here, we describe development and utilization of a lentiviral vector containing enhanced firefly luciferase (luc2) gene. The resulting single cell clones of the mouse mammary gland tumor (4T1-luc2) showed stable light emission in the range of 10,000 photons/sec/cell. In some cases individual 4T1-luc2 cells inserted under the skin of a nu/nu mouse could be detected non-invasively using a cooled CCD camera in some cases. In addition, we showed that only few cells are needed to develop tumors in these mice and tumor progression can be monitored right after the cells are implanted. Significantly higher luciferase activity in these cells allowed us to detect micrometastases in both, syngeneic Balb/c and nu/nu mice.

Manganese adlayers on i-Al-Pd-Mn quasicrystal: growth and electronic structure

Pseudomorphic growth of thin elemental metal films is often observed on a variety of crystalline solids. On quasicrystalline surfaces with their complex structure and the absence of translational periodicity, the situation is different since elemental metals do not exhibit quasicrystalline order, and hence the specific interaction between overlayer and substrate is decisive. Here we study the growth of manganese films on an icosahedral i-Al-Pd-Mn alloy with a view to establishing the growth mode and electronic structure. Although we observe an exponential intensity variation of the adlayer and substrate related x-ray photoemission spectroscopy (XPS) peaks, low energy electron diffraction (LEED) shows that Mn adlayers do not exhibit quasicrystallinity. The detailed structure of the Mn 2p core level line reveals considerable electronic structure differences between the quasicrystalline and elemental metal environment. Evidence of a substantial local magnetic moment on the Mn atoms in the overlayer (about 2.8  µ(B)) is obtained from the Mn 3s exchange splitting.

Effect of a single dislocation in a heterostructure layer on the local polarization of a ferroelectric layer

We study, on an atomic scale, the influence of a single dislocation in a SrTiO3 sublayer on the local ferroelectric polarization of the neighboring ferroelectric PbZr0.2Ti0.8O3 (PZT) sublayer in an epitaxial SrTiO3/PbZr0.2Ti0.8O3/SrTiO3 three-layer heterostructure. The strain field of the dislocation in the SrTiO3 layer propagates across the interface into the PZT layer and leads to a strong variation of the c-lattice parameter of the PZT layer. Accompanying a strong reduction of the c-lattice parameter, the off-center displacements of the Zr/Ti atoms away from the center of the oxygen octahedra are also strongly decreased, resulting in a decrease of the local spontaneous polarization by up to 48%.