Viscous behavior of resin composite cements

The objective of this study was to analyze the viscous behavior during setting reaction of resin composite cements and how it is influenced by temperature. Viscous properties during auto-polymerization at 23°C of three adhesive (Panavia V5 [PV5]; RelyX Ultimate [RUL]; Multilink Automix [MLA]) and three self-adhesive (Panavia SA plus [PSA]; RelyX Unicem 2 Automix [RUN]; Multilink SpeedCem [MSC]) resin composite cements were rheometrically measured. Changes in contact angle and temperature during auto-polymerization were evaluated for each cement at 23°C and 37°C. Rheological analysis and temperature measurements corresponded in terms of curve progression. The tested resin composite cements demonstrated strong variations in their viscous behavior during setting reaction. PV5 and PSA become less viscous at 37°C and then polymerize quickly. For RUL and RUN at 37°C, viscosity rises, and polymerization takes place quickly. MLA and MSC start with high viscosity, then MSC polymerizes very fast and MLA rather slowly.

Dijet Resonance Search with Weak Supervision Using sqrt[s]=13 TeV pp Collisions in the ATLAS Detector

This Letter describes a search for narrowly resonant new physics using a machine-learning anomaly detection procedure that does not rely on signal simulations for developing the analysis selection. Weakly supervised learning is used to train classifiers directly on data to enhance potential signals. The targeted topology is dijet events and the features used for machine learning are the masses of the two jets. The resulting analysis is essentially a three-dimensional search A→BC, for m_{A}∼O(TeV), m_{B},m_{C}∼O(100  GeV) and B, C are reconstructed as large-radius jets, without paying a penalty associated with a large trials factor in the scan of the masses of the two jets. The full run 2 sqrt[s]=13  TeV pp collision dataset of 139  fb^{-1} recorded by the ATLAS detector at the Large Hadron Collider is used for the search. There is no significant evidence of a localized excess in the dijet invariant mass spectrum between 1.8 and 8.2 TeV. Cross-section limits for narrow-width A, B, and C particles vary with m_{A}, m_{B}, and m_{C}. For example, when m_{A}=3  TeV and m_{B}≳200  GeV, a production cross section between 1 and 5 fb is excluded at 95% confidence level, depending on m_{C}. For certain masses, these limits are up to 10 times more sensitive than those obtained by the inclusive dijet search. These results are complementary to the dedicated searches for the case that B and C are standard model bosons.

Efficacy of Plasma-Polymerized Allylamine Coating of Zirconia after Five Years

Plasma-polymerized allylamine (PPAAm) coatings of titanium enhance the cell behavior of osteoblasts. The purpose of the present study was to evaluate a PPAAm nanolayer on zirconia after a storage period of 5 years. Zirconia specimens were directly coated with PPAAm (ZA0) or stored in aseptic packages at room temperature for 5 years (ZA5). Uncoated zirconia specimens (Zmt) and the micro-structured endosseous surface of a zirconia implant (Z14) served as controls. The elemental compositions of the PPAAm coatings were characterized and the viability, spreading and gene expression of human osteoblastic cells (MG-63) were assessed. The presence of amino groups in the PPAAm layer was significantly decreased after 5 years due to oxidation processes. Cell viability after 24 h was significantly higher on uncoated specimens (Zmt) than on all other surfaces. Cell spreading after 20 min was significantly higher for Zmt = ZA0 > ZA5 > Z14, while, after 24 h, spreading also varied significantly between Zmt > ZA0 > ZA5 > Z14. The expression of the mRNA differentiation markers collagen I and osteocalcin was upregulated on untreated surfaces Z14 and Zmt when compared to the PPAAm specimens. Due to the high biocompatibility of zirconia itself, a PPAAm coating may not additionally improve cell behavior.

Abstract 2270: RG7769 (PD1-TIM3), a novel heterodimeric avidity-driven T cell specific PD-1/TIM-3 bispecific antibody lacking Fc-mediated effector functions for dual checkpoint inhibition to reactivate dysfunctional T cells

Based on the unprecedented clinical efficacy of PD-1/PD-L1 pathway checkpoint inhibitors (CPI), non-redundant immune checkpoints like TIM-3, LAG-3, TIGIT or BTLA are currently being targeted, by combinatorial approaches using monospecific or bispecific antibodies. Up-regulation of TIM-3 has been described as an adaptive CPI resistance mechanism, and internal prevalence data on archival samples of CPI-naïve and -experienced patients showed co-expression of PD-1 and TIM-3 in various tumor types, consistent with literature reports. Here, we describe RG7769 (PD1-TIM3), a novel avidity driven heterodimeric PD-1/TIM-3 1+1 bispecific CrossMabVH-VL intentionally designed as high affinity PD-1 (KD 250 pM, 37°C) and low affinity TIM-3 (KD 130 nM, 37°C) Fab-moieties to specifically target PD-1+ and PD-1+ TIM-3+ T cells through avidity gain, while bypassing PD-1- TIM3+ myeloid and NK cells. In contrast to IgG4-based PD-1 antibodies and conventional IgG1-based TIM-3 Fc-effector function competent antibodies, RG7769 harbors a PG LALA containing heterodimeric KiH IgG1 Fc-region rendering the BsAb refractory to drug shaving by FcgR-expressing macrophages in the TME, while retaining IgG-pharmacokinetics. RG7769 binds to PD-1 with higher affinity than pembrolizumab and nivolumab. X-ray crystallography demonstrated that the humanized PD-1 binding Fab recognizes a unique glycosylated epitope on PD-1, and potently blocks the PD-1/PD-L1 and PD-1/PD-L2 interactions in both biochemical and reporter cell line assays. The humanized TIM-3 binding arm was identified for maximal functional activity using mixed lymphocyte reaction (MLR) assays. Compared with bivalent TIM-3 antibodies, RG7769 shows reduced binding to TIM-3+ myeloid and NK cells, but binds preferentially to dysfunctional T cells expressing PD-1 or both PD-1 and TIM-3, like tumor infiltrating lymphocytes (TILs) in the tumor microenvironment. By virtue of its monovalency, RG7769 induced low antibody internalization on activated T cells when compared with bivalent TIM-3 antibodies, overcoming a major cellular sink for TIM-3 antibodies. In functional assays, RG7769 showed increased IFN-γ secretion by in vitro generated tumor-specific T-cells, increased ex vivo tumor-specific effector functions of T cells from PBMCs of melanoma patients, and enhanced the anti-tumor-activity of TILs from melanoma patients when compared to the monospecific parental PD-1 antibody. Finally, RG7769 showed superior efficacy in controlling s.c. MC38 tumor growth in huPD-1/huTIM-3 transgenic C57/BL6 mice compared to the parental PD-1 antibody. In summary, these preclinical data support the use of RG7769 as a monotherapy and as combination partner for the treatment of patients with solid/hematological tumors. A phase I study is currently ongoing in patients with advanced metastatic solid tumors (NCT03708328).

Citation Format: Laura Laura Codarri Deak, Stefan Seeber, Mario Perro, Patrick Weber, Laura Lauener, Standford Chen, Sonja Offner, Stefan Dengl, Friederike Hesse, Adrian Zwick, Marco Boettger, Alexander Bujotzek, Jörg Benz, Guy Georges, Georg Fertig, Valeria Lifke, Jens Fischer, Stephane Leclair, Victor Levitsky, Marta Canamero, Juha Lindner, Sara Colombetti, Stefanie Bendels, Christophe Boetsch, Matthias Fueth, Merlind Muecke, Henry Kao, Pablo Umana, Christian Klein. RG7769 (PD1-TIM3), a novel heterodimeric avidity-driven T cell specific PD-1/TIM-3 bispecific antibody lacking Fc-mediated effector functions for dual checkpoint inhibition to reactivate dysfunctional T cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2270.

CP Properties of Higgs Boson Interactions with Top Quarks in the tt[over ¯]H and tH Processes Using H→γγ with the ATLAS Detector

A study of the charge conjugation and parity (CP) properties of the interaction between the Higgs boson and top quarks is presented. Higgs bosons are identified via the diphoton decay channel (H→γγ), and their production in association with a top quark pair (tt[over ¯]H) or single top quark (tH) is studied. The analysis uses 139  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of sqrt[s]=13  TeV with the ATLAS detector at the Large Hadron Collider. Assuming a CP-even coupling, the tt[over ¯]H process is observed with a significance of 5.2 standard deviations. The measured cross section times H→γγ branching ratio is 1.64_{-0.36}^{+0.38}(stat)_{-0.14}^{+0.17}(sys)  fb, and the measured rate for tt[over ¯]H is 1.43_{-0.31}^{+0.33}(stat)_{-0.15}^{+0.21}(sys) times the Standard Model expectation. The tH production process is not observed and an upper limit on its rate of 12 times the Standard Model expectation is set. A CP-mixing angle greater (less) than 43 (-43)° is excluded at 95% confidence level.

Biodegradable, lignin-based encapsulation enables delivery of Trichoderma reesei with programmed enzymatic release against grapevine trunk diseases

Antagonistic fungi such as Trichoderma reesei are promising alternatives to conventional fungicides in agriculture. This is especially true for worldwide occurring grapevine trunk diseases, causing losses of US$1.5 billion every year, at which conventional fungicides are mostly ineffective or prohibited by law. Yet, applications of Trichoderma against grapevine trunk diseases are limited to preventive measures, suffer from poor shelf life, or uncontrolled germination. Therefore, we developed a mild and spore-compatible layer-by-layer assembly to encapsulate spores of a new mycoparasitic strain of T. reesei IBWF 034-05 in a bio-based and biodegradable lignin shell. The encapsulation inhibits undesired premature germination and enables the application as an aqueous dispersion via trunk injection. First injected into a plant, the spores remain in a resting state. Second, when lignin-degrading fungi infect the plant, enzymatic degradation of the shell occurs and germination is selectively triggered by the pathogenic fungi itself, which was proven in vitro. Germinated Trichoderma antagonizes the fungal pathogens and finally supplants them from the plant. This concept enables Trichoderma spores for curative treatment of esca, one of the most infective grapevine trunk diseases worldwide.

Surface structuring of zirconia to increase fibroblast viability

OBJECTIVE

The neck area of zirconia implants or abutments is currently either machined, polished and in some cases additionally heat-treated. The aim of the present study was to determine how the surface topography and crystalline structure of zirconia affects the viability of human gingival fibroblasts (HGF-1).

METHODS

Zirconia discs with a diameter of 13mm were either polished [Zp], polished and heat-treated [Zpt], machined [Zm], machined and heat-treated [Zmt] or sandblasted, etched and heat-treated [Z14] which is the surface topography of the endosseous part of a zirconia implant. The specimen surfaces were analyzed using scanning electron microscopy (SEM), characterized in terms of monoclinic to tetragonal phase ratio, storage effect on wettability and roughness. The viability and morphology of HGF-1 cells was then tested on all surfaces after 24h.

RESULTS

The effect of the heat-treatment was visualized for the polished specimens with SEM. Contact angle of water was significantly decreased after 2 weeks air storage of the zirconia. Cell viability was significantly higher on smooth surfaces (Zpt, Zm, Zmt) when compared to Z14. HGF-1 cells spread very flat and attached tightly to the smoother surfaces Zp, Zpt, Zm and Zmt while on Z14, cells did not fully extend into the etched morphology of zirconia and stretched over longer distances.

SIGNIFICANCE

For the structuring of the neck part of zirconia implants or abutments, a smooth surface with exposed grains might be suggested as the optimal substrate for human gingival fibroblasts. The wettability with water of zirconia decreases with prolonged air storage.

Antiferromagnetic textures in BiFeO3 controlled by strain and electric field

Antiferromagnetic thin films are currently generating considerable excitement for low dissipation magnonics and spintronics. However, while tuneable antiferromagnetic textures form the backbone of functional devices, they are virtually unknown at the submicron scale. Here we image a wide variety of antiferromagnetic spin textures in multiferroic BiFeO₃ thin films that can be tuned by strain and manipulated by electric fields through room-temperature magnetoelectric coupling. Using piezoresponse force microscopy and scanning NV magnetometry in self-organized ferroelectric patterns of BiFeO₃, we reveal how strain stabilizes different types of non-collinear antiferromagnetic states (bulk-like and exotic spin cycloids) as well as collinear antiferromagnetic textures. Beyond these local-scale observations, resonant elastic X-ray scattering confirms the existence of both types of spin cycloids. Finally, we show that electric-field control of the ferroelectric landscape induces transitions either between collinear and non-collinear states or between different cycloids, offering perspectives for the design of reconfigurable antiferromagnetic spin textures on demand.

Tailoring antiferromagnetic domains is critical for the development of low-dissipative spintronic and magnonic devices. Here the authors demonstrate the control of antiferromagnetic spin textures in multiferroic bismuth ferrite thin films using strain and electric fields.

Influence of Material and Surface Roughness of Resin Composite Cements on Fibroblast Behavior

Clinical Relevance

A well-polished cement surface increases the viability and spreading of gingival fibroblasts. The tested resin composite cements did not reveal any cytotoxic effects.

SUMMARY

Objective: This in vitro study aimed to investigate the effect of cement type and roughness on the viability and cell morphology of human gingival fibroblasts (HGF-1).

Methods and Materials: Discs of three adhesive (Panavia V5 [PV5], Multilink Automix [MLA], RelyX Ultimate [RUL] and three self-adhesive (Panavia SA plus [PSA], SpeedCem plus [SCP], RelyX Unicem [RUN]) resin composite cements were prepared with three different roughnesses using silica paper grit P180, P400, or P2500. The cement specimens were characterized by surface roughness and energy-dispersive X-ray spectroscopic mapping. A viability assay was performed after 24 hours of incubation of HGF-1 cells on cement specimens. Cell morphology was examined with scanning electron microscopy.

Results: The roughness of the specimens did not differ significantly among the different resin composite cements. Mean Ra values for the three surface treatments were 1.62 ± 0.34 μm for P180, 0.79 ± 0.20 μm for P400, and 0.17 ± 0.08 μm for P2500. HGF-1 viability was significantly influenced by the cement material and the specimens’ roughness, with the highest viability for PSA ≥ RUN = MLA ≥ SCP = PV5 > RUL (p<0.05) and for P2500 = P400 > P180 (p<0.001). Cell morphology did not vary among the materials but was affected by the surface roughness.

Conclusion: The composition of resin composite cements significantly affects the cell viability of HGF-1. Smooth resin composite cement surfaces with an Ra of 0.2–0.8 μm accelerate flat cell spreading and formation of filopodia.

Guidelines for treatment of umbilical and epigastric hernias from the European Hernia Society and Americas Hernia Society

BACKGROUND

Umbilical and epigastric hernia repairs are frequently performed surgical procedures with an expected low complication rate. Nevertheless, the optimal method of repair with best short- and long-term outcomes remains debatable. The aim was to develop guidelines for the treatment of umbilical and epigastric hernias.

METHODS

The guideline group consisted of surgeons from Europe and North America including members from the European Hernia Society and the Americas Hernia Society. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach, the Scottish Intercollegiate Guidelines Network (SIGN) critical appraisal checklists, and the Appraisal of Guidelines for Research and Evaluation (AGREE) instrument were used. A systematic literature search was done on 1 May 2018, and updated on 1 February 2019.

RESULTS

Literature reporting specifically on umbilical and epigastric hernias was limited in quantity and quality, resulting in a majority of the recommendations being graded as weak, based on low-quality evidence. The main recommendation was to use mesh for repair of umbilical and epigastric hernias to reduce the recurrence rate. Most umbilical and epigastric hernias may be repaired by an open approach with a preperitoneal flat mesh. A laparoscopic approach may be considered if the hernia defect is large, or if the patient has an increased risk of wound morbidity.

CONCLUSION

This is the first European and American guideline on the treatment of umbilical and epigastric hernias. It is recommended that symptomatic umbilical and epigastric hernias are repaired by an open approach with a preperitoneal flat mesh.

EHS and AHS guidelines for treatment of primary ventral hernias in rare locations or special circumstances

Background

Rare locations of hernias, as well as primary ventral hernias under certain circumstances (cirrhosis, dialysis, rectus diastasis, subsequent pregnancy), might be technically challenging. The aim was to identify situations where the treatment strategy might deviate from routine management.

Methods

The guideline group consisted of surgeons from the European and Americas Hernia Societies. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used in formulating the recommendations. The Scottish Intercollegiate Guidelines Network (SIGN) critical appraisal checklists were used to evaluate the quality of full‐text papers. A systematic literature search was performed on 1 May 2018 and updated 1 February 2019. The Appraisal of Guidelines for Research and Evaluation (AGREE) instrument was followed.

Results

Literature was limited in quantity and quality. A majority of the recommendations were graded as weak, based on low quality of evidence. In patients with cirrhosis or on dialysis, a preperitoneal mesh repair is suggested. Subsequent pregnancy is a risk factor for recurrence. Repair should be postponed until after the last pregnancy. For patients with a concomitant rectus diastasis or those with a Spigelian or lumbar hernia, no recommendation could be made for treatment strategy owing to lack of evidence.

Conclusion

This is the first European and American guideline on the treatment of umbilical and epigastric hernias in patients with special conditions, including Spigelian and lumbar hernias. All recommendations were weak owing to a lack of evidence. Further studies are needed on patients with rectus diastasis, Spigelian and lumbar hernias.

Heterogeneous Clusters of Phthalocyanine and Water Prepared and Probed in Superfluid Helium Nanodroplets

Superfluid helium nanodroplets comprised of thousands to millions of helium atoms can serve as a reactor for the synthesis of heterogeneous molecular clusters at cryogenic conditions. The cluster synthesis occurs via consecutive pick-up of the cluster building blocks by the helium droplet and their subsequent coalescence within the droplet. The effective collision cross section of the building blocks is determined by the helium droplet size and thus exceeds by orders of magnitude that of a reactive collision in the gas phase. Moreover, the cryogenic helium environment (at 0.38 K) as a host promotes the formation of metastable cluster configurations. The question arises as to the extent of the actual involvement of the helium environment in the cluster formation. The present study deals with clusters of single phthalocyanine (Pc) molecules with single water molecules. A large fluorophore such as Pc offers several sites where the water molecule can attach. The resulting isomeric variants of the Pc-H₂O complex can be selectively identified by electronic spectroscopy. We compare the experimental electronic spectra of the Pc-H₂O complex generated in superfluid helium nanodroplets with the results of quantum-chemical calculations on the same cluster but under gas-phase conditions. The number of isomeric variants observed in the helium droplet experiment comes out the same as that obtained from our gas-phase calculations.

[Career Prospects for Young Physicians in Infectious Diseases]

Infectious Diseases are a cross-sectional area connected to various medical disciplines and offer interested physicians multiple working opportunities. The spectrum of infectious diseases covers both out- and inpatient care as well as basic, clinical and epidemiological research. The need for infectious diseases specialists is increasing, thus career prospects are promising. Working conditions in infectious diseases are comparatively family-friendly. With this article we intend to arouse interest for working in the fascinating fields of infectious diseases and provide information on career opportunities. Data from a recently conducted survey among members of the German Society of Infectious Diseases deliver insight, how infectious disease specialists work today.

HF etching of CAD/CAM materials: influence of HF concentration and etching time on shear bond strength

Background

The required pretreatment of CAD/CAM ceramic materials before resin composite cement application varies among studies. The aim of the present study was to evaluate the effect of hydrofluoric acid concentration and etching time on the shear bond strength (SBS) of two adhesive and two self-adhesive resin composite cements to different CAD/CAM ceramic materials.

Methods

SBS of two adhesive (Panavia V5, Kuraray, [PV5]; Vita Adiva F-Cem, Vita Zahnfabrik, [VAF]) and two self-adhesive (RelyX Unicem 2 Automix, 3 M Espe, [RUN]; Vita Adiva S-Cem, Vita, [VAS]) cements to four different CAD/CAM materials (Vitablocs Mark II, Vita, [VM]; Vita Enamic, Vita, [VE]; e.max CAD, Ivoclar Vivadent, [EC]; Vita Suprinity PC, Vita, [VS]) was measured. The effect of the surface pretreatment by using two different hydrofluoric acid products (HF5% Vita Ceramics Etch, Vita and HF9% buffered, Ultradent Porcelain Etch, Ultradent Products) were assessed at etching times of 0 s, 5 s, 15 s, 30s and 60s for each cement and restorative material combination (n = 10 per group, total n = 1440).

Results

Significant effects were found for the etching time and cement for all materials with highest shear bond strength for etching times of 60s = 30s = 15 s ≥ 5 s > 0 s and for RUN>PV5 = VAF > VAS (p < 0.05). Etching with HF5% for 5 s to 15 s resulted in higher SBS values, while no differences were observed between HF5% and HF9% buffered when the substrates were etched for 30s to 60s (p < 0.05).

Conclusions

Within the limitations of this study the recommended surface pretreatment of silicate ceramics is HF etching with concentrations of 5% or 9% for 15 s to 60s to achieve highest shear bond strength while the glassy matrix is sufficiently dissolved. The tested resin composite cements can be applied with all tested materials and suggested for clinical application.

[Influence of culture and religion on the treatment of cancer patients]

Religion, which is one of the most important sources of human identity, has so far hardly been taken into account in the clinic. In the largely secularized society of Germany, this has played a highly subordinate role. Currently, however, the development towards a multireligious society is emerging, which will also be reflected in everyday medical care. Disease and mortality in patients can affect different cultural-religious spheres. Although distinction between cultural and religious aspects is possible, it is not necessary for clinical practice. In the situation of oncological therapy, questions may arise which must be answered differently in the religions Christianity, Judaism and Islam and which should be taken into account when selecting therapy. The consideration of cultural-religious rules can intensify the patient's acceptance, but it can also impair it in case of disregard. Such peculiarities can be the separation into male and female spheres or the restriction of certain auxiliary substances or drugs (blood products, narcotics). Kübler-Ross's phase model is suitable for determining where cultural-religious sensitivities should be taken into account in the phases of disease and how cultural-religious offerings can benefit the course of therapy. Due to large individual, regional, cultural and confessional differences, no systematic catalogue of procedures can be provided here. However, knowledge of such differences, more sensitive interaction with patients and their families and cooperation with hospital pastors can strengthen the relationship of trust between doctor and patient and thus improve the conditions for successful oncological therapy. These aspects should not be underestimated when treating people of other faiths in Germany's secular society.