Tunable Phonon Polariton Hybridization in a van der Waals Hetero-Bicrystal

Phonon polaritons, the hybrid quasiparticles resulting from the coupling of photons and lattice vibrations, have gained significant attention in the field of layered van der Waals heterostructures. Particular interest has been paid to hetero-bicrystals composed of molybdenum oxide (MoO3) and hexagonal boron nitride (hBN), which feature polariton dispersion tailorable via avoided polariton mode crossings. In this work, we systematically study the polariton eigenmodes in MoO3-hBN hetero-bicrystals self-assembled on ultrasmooth gold using synchrotron infrared nanospectroscopy. We experimentally demonstrate that the spectral gap in bicrystal dispersion and corresponding regimes of negative refraction can be tuned by material layer thickness, and we quantitatively match these results with a simple analytic model. We also investigate polaritonic cavity modes and polariton propagation along "forbidden" directions in our microscale bicrystals, which arise from the finite in-plane dimension of the synthesized MoO3 micro-ribbons. Our findings shed light on the unique dispersion properties of polaritons in van der Waals heterostructures and pave the way for applications leveraging deeply sub-wavelength mid-infrared light matter interactions. This article is protected by copyright. All rights reserved.

[Mid-term efficacy evaluation of ABO incompatible living relative kidney transplantation based on protocol biopsy]

Objective: To evaluate the mid-term efficacy of ABO incompatible living donor kidney transplantation (ABOi-KT) based on the results of routine renal biopsy for transplantation. Methods: Retrospective collection of clinical data from 23 pairs of ABOi-KT donors and recipients at the First Affiliated Hospital of Sun Yat-sen University from July 2015 to November 2021. ABOi-KT was performed on recipients after desensitization treatment, and the results of routine kidney transplant biopsy at 1 week, 1 month, 3 months, 6 months, and 12 months after surgery were analyzed. Combined with blood type antibody levels and renal function recovery, the mid-term efficacy of ABOi-KT was evaluated. Results: Among the 23 recipients, there were 19 males and 4 females; age range from 19 to 47 years old [(29.6±6.7) years old], all underwent ABOi-KT successfully after receiving desensitization treatment. The follow-up time was (44.6±22.4) months, of which 22 cases were followed up for more than 1 year. The incidence rates of rejection reactions at 1 week, 1 month, 3 months, 6 months, and 12 months after surgery were 15.0% (3/20), 11.1% (1/9), 7.7% (1/13), 25.0% (3/12), and 12.5% (1/8), respectively. For receptors with rejection reactions, targeted anti-rejection therapy was performed based on clinical symptoms and various indicators. Borderline T cell mediated rejection (TCMR) can be converted to mild tubular inflammation after anti-rejection treatment. The positive rate of complement C4d in peritubular capillaries was 95.0% (19/20) one week after surgery, and the positive rate of complement C4d was 100% at 3 and 12 months after surgery. The cumulative survival rates at 1, 3, 5, and 7 years after surgery were all 100%. The cumulative survival rates at 1, 3, 5, and 7 years after kidney transplantation were 100%, 93.3%, 84.0%, and 84.0%, respectively. Except for 2 recipients who underwent transplantation in 2017 and experienced kidney failure at 30 and 49 months after surgery, all other transplanted kidneys survived. Conclusions: The results of routine renal transplant biopsy show that ABOi-KT has a good mid-term therapeutic effect. The pathological changes of ABOi-KT can be dynamically observed through routine renal transplant biopsy and targeted treatment for rejection reactions can be provided accordingly.

Hyperbolic Polaritonic Rulers Based on van der Waals α-MoO3 Waveguides and Resonators

Low-dimensional, strongly anisotropic nanomaterials can support hyperbolic phonon polaritons, which feature strong light-matter interactions that can enhance their capabilities in sensing and metrology tasks. In this work, we report hyperbolic polaritonic rulers, based on microscale α-phase molybdenum trioxide (α-MoO3) waveguides and resonators suspended over an ultraflat gold substrate, which exhibit near-field polaritonic characteristics that are exceptionally sensitive to device geometry. Using scanning near-field optical microscopy, we show that these systems support strongly confined image polariton modes that exhibit ideal antisymmetric gap polariton dispersion, which is highly sensitive to air gap dimensions and can be described and predicted using a simple analytic model. Dielectric constants used for modeling are accurately extracted using near-field optical measurements of α-MoO3 waveguides in contact with the gold substrate. We also find that for nanoscale resonators supporting in-plane Fabry-Perot modes, the mode order strongly depends on the air gap dimension in a manner that enables a simple readout of the gap dimension with nanometer precision.

Closing the Loop: Toward Sustainable 3D Print Recycling in the Clinic

PURPOSE/OBJECTIVE(S)

THREE-DIMENSIONAL (: 3D) printing is becoming ubiquitous in Radiation Therapy resulting in large amounts of plastic waste generated. We report on the feasibility, workflows, material properties and cost effectiveness of 3D print recycling to increase sustainability of 3D printing in clinics.

MATERIALS/METHODS

Polylactic acid (PLA) prints were recycled using a consumer-grade recycling system consisting of i) plastic shredder to granulate used prints ii) heated extruder to melt material into filament iii) fan-cooled path for rapid cooling iv) spooling rig and v) pelletizer to cut filament into more regularized pellets as input material for step ii). The recovery percentage of material was characterized after each step by weighing inputs/outputs; timing and workloads were also recorded. Resulting recycled filaments were characterized in diameter and tensile strength and were compared between two different extruder nozzle configurations and with vs without pelletization to find an optimal recycling process. Recycled filament was finally used to create clinical items and evaluated. Lastly, a cost analysis over the past 1 year of recycling use was performed to determine the cost effectiveness of the recycling system.

RESULTS

PLA prints were recycled with an overall efficiency of 79.3 ± 12.2% (standard deviation) between color batch runs. The best recycled filament quality was produced using the pelletization process and wider 3.25mm extruder nozzle. Relative to new filament, tensile strength testing showed recycled filament strength was 79% vs 70% (pelletized vs unpelletized) and 86% vs 60% (3.25mm vs 2.85mm nozzle). Extrusion and spooling procedures proved difficult to optimize, requiring lots of operator supervision (∼45 minutes per spool, mean 475g) and achieved a best filament diameter of 2.85 ± 0.09mm. A cost analysis shows that without accounting for operator time, it would require over 25 years to recoup the cost of the recycling system.

CONCLUSION

Over the past 1-year, clinical 3D printing at our site consisted of 40 patient boluses and 25 electron cutouts, consuming about 6.5kg of PLA. Due to infection control concerns only 35% of this material was eligible for recycling, however 3.5 times that amount was collected from other printing activities. Recycling reduced new filament use by 56% ($470). Recycling workflows proved difficult to streamline and resulted in filament diameter that was marginally outside common industry standards and about 20% less strong but deemed adequate for clinical printing. Although the cost savings analysis indicates a poor return on investment, increasing the scale of the operation would be beneficial. To achieve this, we plan to recycle PLA boluses after disinfection and solicit other clinics in our hospital network and local 3D printing hobbyist community to recycle their prints.

An Online AI-Powered Interactive Histological Image Annotation Platform for Analyzing Intestinal Regenerating Crypts in Post-Irradiated Mice

PURPOSE/OBJECTIVE(S)

The goal of this project is to build an online AI-powered interactive annotation platform to accurately and efficiently annotate intestinal regenerating crypts in histological images of mice after abdominal irradiation.

MATERIALS/METHODS

The proposed platform is developed by the seamless integration of a front-end web client and a back-end server. Such client/server design allows the users to access the platform without software installation on local computers. Our front-end client is developed with SvelteJS + WebGL technology stack, allowing access from any common web browsers and enabling user interaction, such as image importing/visualization, interactive crypt annotating, and annotation saving/deleting. The back-end server is responsible for executing the tasks requested from the web client, for instance, image pre-processing, AI-based crypts automatic identification, and database management. The image preprocessing is designed to extract a single cross section image using morphological operations because multiple hematoxylin and eosin (H&E) stained jejunum cross sections from post-irradiated mice are scanned within one slide. The auto-crypt identification is powered by a trained and validated AI engine U-Net, classifying image grid tiles into two groups with and without regenerating crypts. The database is implemented with the self-contained SQLite to support recording and indexing the annotated grid tiles with regenerating crypts. The workflow for crypt analysis on this interactive platform has 5 steps: 1) manually import a whole H&E slide image; 2) auto-preprocess the slide by extracting single cross-section images; 3) auto-identify regenerating crypts with an AI engine; 4) interactively annotate (add, delete, modify) auto-identified crypt markers; 5) save and/or output the annotation to the database or the local drive.

RESULTS

The performance of the developed interactive crypt analysis platform was evaluated in aspects of accuracy and efficiency. The AI-powered crypt auto-identification accuracy was assessed by computing the mean absolute error (MAE) on crypt number per cross section between manual and auto annotation using a testing dataset containing 80 cross sections. It achieved an MAE of 3.5±4.8 crypts per cross section, and 81.25% of the cross sections have no more than 5 crypts difference. The efficiency was assessed under two conditions with the server on the cloud and a local computer. It took about 2-3 minutes to finish the entire workflow on the cloud, while 1-2 minutes on the local by saving ∼1 minute on image uploading.

CONCLUSION

The developed web client/server platform enables online automatic identification and interactive annotation of mice crypts in minutes. It is a convenient tool that allows accurate and efficient crypt analysis and can be extended for other histologic image analyses.

A Pilot Study of an Interactive Virtual Tour Tool for Patient Education Prior to Undergoing High-Dose Rate Brachytherapy for Prostate Cancer

PURPOSE/OBJECTIVE(S)

High-dose rate (HDR) brachytherapy for treatment of prostate cancer is an invasive procedure that can be associated with patient anxiety. Patient education regarding the procedure can allow for better informed decision-making while also decreasing anxiety. We sought to develop and assess the utility of an interactive virtual tour tool that portrays a 360-degree view of the HDR brachytherapy patient experience, with the goals of providing patient education, decreasing patient anxiety, and assisting in wayfinding on the procedure day.

MATERIALS/METHODS

Using a 360-degree camera, we captured multiple photographs that depicted the various hospital locations that a patient would navigate through on the day of their HDR brachytherapy procedure, including the medical center lobby, pre-operative/post-operative units, and the brachytherapy suite. We then compiled these 360-degree photographs using virtual tour software, to allow users to navigate throughout the locations. We added informational text, spoken audio, and videos associated with key staff, objects, and the brachytherapy procedure that allow the users to interact with and learn about these various components within the virtual tour. This tool was accessible via a website link on a computer, tablet, or smartphone and was provided at the time of consult to patients who were planning to undergo HDR brachytherapy for prostate cancer. A questionnaire assessing the tool's ease of use, educational value, wayfinding utility, and ability to improve anxiety and treatment decision-making was conducted prior to and after their procedure.

RESULTS

Preliminary feedback from healthy volunteers is highly positive, with users finding that the tool is easily accessible, user-friendly, improves understanding of HDR brachytherapy, simulates the treatment experience accurately, helps with wayfinding, and has the potential to decrease patient anxiety and increase comfort with the treatment decision. Data from the patient questionnaires are being collected and will be analyzed.

CONCLUSION

A 360-degree virtual tour tool allows for an easily accessible, immersive, and interactive method of patient education on an invasive, anxiety-associated procedure. This has the potential to decrease patient anxiety and improve comfort regarding treatment decision-making. This tool may be applied toward other relatively involved radiotherapy modalities, including gynecologic HDR brachytherapy, respiratory-gated treatments, and CyberKnife stereotactic radiosurgery.

Deep Learning-Based Pipeline for Automatic Identification of Intestinal Regenerating Crypts in Mouse Histological Images

PURPOSE/OBJECTIVE(S)

A classical approach for evaluating normal tissue radiation response is to count the number of intestinal regenerating crypts in mouse histological images acquired after abdominal radiation. However, manual counting is time-consuming and subject to inter-observer variations. The goal of this study is to build a deep learning-based pipeline for automatically identifying intestinal regenerating crypts to facilitate high-throughput studies.

MATERIALS/METHODS

Sixty-six healthy C57BL/6 female mice underwent 16 MeV whole abdominal electron irradiation. The small bowel was collected from each mouse 4 days post-irradiation, and 9 jejunal cross-sections from each were processed together in a single slide. The slides were stained with hematoxylin and eosin (H&E) and subsequently scanned (x20), providing one electronic histological image per mouse. Regenerating crypts, consisting of more than 10 basophilic crypt epithelial cells, were manually identified using point annotations in histological images. The pipeline was built to take the input of the image containing 9 cross sections and automatically identify the regenerating crypts on each cross section. It mainly consists of two components, cross section segmentation using intensity thresholding and morphological operations and crypt identification using a UNet. The dataset was randomly split into 46, 10, and 10 slide images for UNet training, validation, and testing. Each slide image was split into grid tiles with a voxel size of 200 × 200, and 40 × 40 square masks were placed with centers at manual point annotations on tiles with regenerating crypts. 5203/5198 tiles (w/wo crypt mask) were extracted to train UNet by minimizing dice loss. The mask probability map generated by the UNet was post-processed to identify the crypt position. Postprocessing hyperparameters were tuned using the validation dataset. The model accuracy was evaluated using the testing dataset by computing the mean absolute error (MAE) of the crypt number averaged across all cross sections.

RESULTS

The number of regenerating crypts on testing cross sections ranges from 1 to 63. The testing cross-section-wise MAE achieved by the platform is 3.5±4.8 crypts. 81.25% of testing cross sections have absolute number differences less than or equal to 5 crypts.

CONCLUSION

Our established deep learning-based pipeline can accurately count the number of regenerating crypts in mouse intestinal histological images. We have integrated it into an online platform that enables automatic crypt identification and allows users to interactively modify auto-identified crypt annotations. The acquired annotations from the platform will be used to finetune the deep learning model to achieve better identification performance.

Equivalent Dose Estimation in FLASH Irradiation with a Deep Learning Approach

PURPOSE/OBJECTIVE(S)

Ultra-high dose rate (FLASH) irradiation has been reported to provide decreased normal tissue toxicity without compromising tumor control compared with conventional (CONV) irradiation. However, a comprehensive understanding of the FLASH biological effect requires precise quantification of radiobiology. The study is to explore whether deep learning (DL) can tackle the task. As a proof of concept, we investigate a DL model for estimating FLASH dose to its equivalent CONV dose.

MATERIALS/METHODS

Healthy C57Bl/6 female mice underwent FLASH (200Gy/s; n = 43) or CONV (0.12Gy/s; n = 41) whole abdominal irradiation using ∼16 MeV electron beams with a dose escalation scheme of 5 groups (n = 8 or 9) at 1Gy increments: 12-16Gy FLASH, 11-15Gy CONV. 4 days post-irradiation, 9 jejunum cross-sections per mouse were H&E stained for histological analysis. Each cross-section image was processed to remove lumen background and oversampled into multiple large-scale and small-scale patches along jejunal circumference. In CONV dataset, we randomly selected the data of 32 mice (80%) for model training and the rest (20%) for model validation. A ResNet101-based DL model, pre-trained with an unsupervised contrastive learning scheme, was retrained with only CONV training set to estimate corresponding CONV dose. For comparison, a crypt counting (CC) approach was implemented by manually counting the number of regenerating crypts on each cross-section image. An exponential function of dose vs crypt number was fitted with the CONV training set and used for dose estimation on the testing set. Mean squared error (MSE) was used to assess the accuracy of DL and CC approaches in estimating dose levels in CONV irradiation. The validated DL model was applied to the FLASH set to project FLASH dose into corresponding CONV dose that results in equivalent biological response.

RESULTS

The CONV dose estimated by DL and CC approaches and DL-estimated FLASH equivalent dose were summarized in Table 1. The DL model achieved an MSE of 0.21 Gy2 on CONV testing set compared with 0.32 Gy2 of the CC approach. FLASH equivalent dose estimated by DL model for 12, 13, 14, 15 and 16Gy were 12.16±0.40, 12.53±0.32, 12.72±0.24, 12.85±0.20 and 13.04±0.27 Sv, respectively.

CONCLUSION

Our proposed DL model can accurately estimate the CONV dose based on histological images. The DL predictions of FLASH dataset demonstrate that FLASH may reduce normal tissue toxicity with a lower equivalent dose, especially at high irradiated dose levels. Our study indicates that deep learning can be potentially used to assess the equivalent dose of FLASH irradiation to normal tissue.

Anatomically Realistic 3D Printed Mouse Phantom for Multi-Institutional Benchmarking of FLASH and CONV Irradiation

PURPOSE/OBJECTIVE(S)

It is reported that about US$28B/year is spent on pre-clinical studies that are not reproducible. FLASH studies may suffer from the same reproducibility crisis due to the non-standard nature of the FLASH beamlines and the lack of dosimeters that can function at ultra-high dose-rates. There have been reports of different outcomes with regard to the FLASH effect across different institutions, even though similar beamlines, temporal structure, and nominal dose levels were used. This brings up the question of the accuracy of dosimetry under FLASH conditions for a fair comparison between FLASH and CONV. To answer this question, we develop and characterize an anatomically realistic 3D-printed mouse phantom to be used in a multi-institutional dosimetric benchmarking effort.

MATERIALS/METHODS

Mesh files for bony anatomy, lungs, and soft tissue derived from a CT scan of a mouse were converted to an editable 3D model. The 3D model was cut along the coronal plane and modified to allow the inclusion of radiographic film. A multi-material approach was employed to print the phantom. A dual-nozzle 3D printer was used, where one of the nozzles used Acrylonitrile butadiene styrene (ABS) to mimic soft tissue and the other nozzle used Polyactic acid (PLA) to mimic bone density. The two materials were used together in a single print. Lungs were approximated by lightweight PLA and were printed separately and inserted into corresponding cavities in the phantom. Hounsfield Units (HU) and print-to-print stability were verified. Radiographic films were laser cut for different anatomical sites. Two institutes took part in this study with data pending from 3 more institutions. The institutes were instructed to deliver 10 Gy to the plane of the film for the whole abdomen, whole lung, and brain irradiations. 2D dose maps were compared between FLASH and CONV, and the deviation from the prescribed dose was also measured.

RESULTS

The 3D-printed soft tissue, bone, and lung densities were measured to be ∼ 1.01 g/cc, 1.22 g/cc, and 0.44 g/cc, respectively. For soft tissue and bone, the Hounsfield unit (HU) difference from one print to another was < 10 HU. The greatest variation was within the lungs (54 HU), but this had a minimal effect on the dose distribution (<1%). For the two institutions that completed the survey, the maximum average difference between FLASH and CONV for all irradiations was 0.75 Gy (7.48%). The maximum average difference from the prescribed dose for all irradiations was 0.7 Gy (7.20%) across both institutions. The largest discrepancy was generally observed to be for lung irradiation, indicating that lack of treatment planning systems limits our ability to prescribe accurately in areas of inhomogeneities.

CONCLUSION

A 3D printed anatomically realistic mouse phantom was developed, characterized, and used in a multi-institutional dosimetric benchmarking effort. Such a study is paramount for the clinical translation of FLASH as it facilitates reduced variability from one institution to another.

Technical Infrastructure for Clinical Translation of Electron FLASH

PURPOSE/OBJECTIVE(S)

For safe clinical translation of electron FLASH, hardware tools for real-time beam control and software tools for treatment planning are necessary. The purpose of this study is to prototype high-throughput hardware for real-time beam control, along with accurate beam modeling of a modern clinical Linac configured to deliver FLASH dose-rates.

MATERIALS/METHODS

For real-time beam current monitoring, a beam current transformer (BCT) was initially coupled to a fast digitizer and its linearity was established by varying dose per pulse. The radiation pulse width was modified, and this change was measured using the BCT. The BCT was then used to measure the variability of dose per pulse and pulse width due to a mistuned linear accelerator system. Next, the BCT was interfaced with a field programmable gate array (FPGA) which provides the ability for high-throughput and deterministic control of the Linac based on dose accumulation. For beam modeling, the program, TOol for PArticle Simulation (TOPAS), was used to obtain beam parameters by using Bayesian optimization of the beam energy, source size, angular, and energy spread via comparison of simulated and representative dose profiles. The beam model would then be employed to calculate 3D dose distribution in a CT scan of a 3D-printed anatomically realistic mouse phantom.

RESULTS

The area under the current-time curve from the BCT exhibited excellent linearity (response = 12.80 nC/Gy) up to 2.5 Gy/Pulse (R2 = 0.99). The peak beam current for the electron FLASH beam was measured to be ∼10 mA for an instantaneous dose-rate of ∼5×105 Gy/s. The measured radiation pulse width agreed with the expected value (3.7 μs). The pulse width was then shortened and the measurement by the BCT indicated pulse widths of 1.8 μs and 0.5 μs corresponding to 0.7 Gy/pulse and 0.3 Gy/pulse, respectively. The beamline exhibited a ramp-up in dose per pulse and pulse width when using the automatic frequency controller (AFC). For the first pulse, the dose delivered was ∼0.1-0.3 Gy and the pulse width was 0.6 μs. The output stabilized to nominal values of dose and pulse width after 3-4 pulses. This ramp-up was mitigated by manually tuning the RF resonance with the AFC disabled, after which the BCT exhibited constant output and pulse width. The beam modeling work is in progress.

CONCLUSION

We demonstrated that a BCT can provide real-time measurement of per-pulse output suitable as input for FLASH beam control based on dose accumulation. The next steps are to quantify the accuracy of the dose control mechanism with the FPGA-based hardware. Potential failure modes will be identified and mitigated in parallel with the development of the hardware. A 3D-printed mouse phantom has been constructed to facilitate beam modeling work for treatment planning (in progress). On completion of this work, it is expected that we will have key infrastructure elements needed to move towards an eventual FDA investigational device exemption for clinical trials.

Comparison of Tumor Control between FLASH and CONV in an Orthotopic Breast Cancer Model

PURPOSE/OBJECTIVE(S)

Post-lumpectomy radiotherapy (RT) reduces in-breast tumor recurrence by eradicating residual, occult breast cancer (BC) that may be in the mm size scale. The ability of FLASH-RT to eradicate BC relative to conventional dose rate (CONV) RT is unknown. ∼ 20Gy RT is currently used clinically for single-fraction breast IORT. Determine the effectiveness of FLASH compared to CONV in eradicating small tumors in an orthotopic, syngeneic model of BC using single-fraction 20 or 30Gy RT.

MATERIALS/METHODS

Radiation sensitive, mammary tumor cell line Py117 from the transgenic model of the mouse mammary tumor virus promoter driving the polyoma middle T antigen (MMTV- PyMT) efficiently forms non-metastatic, orthotopic tumors in C57BL/6 mice. 106 Py117 cells were injected orthotopically into the left 4th mammary fat pad of C57Bl/6J mice. Radiotherapy was performed with a custom jig that allows for fixed positioning of the target volume (2x2cm radiation field) with 5mm of margin into surrounding tissue. Tumors were irradiated at ∼30mm3 volume or, for comparison, at a range of greater volumes (200-800mm3) with 20 or 30Gy FLASH or CONV with 16-17 MeV electrons.

RESULTS

Small 30mm3 tumors regressed until ∼ day 15 after 20Gy single fraction RT then regrew for both FLASH and CONV. 30mm3 tumors were eradicated with both FLASH and CONV at 30Gy with no regrowth up to day 35 post-RT. Larger tumors irradiated with 30Gy regressed until ∼ day 12 post-RT then regrew for both FLASH and CONV. There was no significant difference in growth delay or tumor eradication between FLASH and CONV in any cohort.

CONCLUSION

FLASH was as effective as CONV in controlling growth and eradicating murine BC. Based on other preclinical studies, single-fraction doses between 20 and 30Gy, as well as hypofractioned RT schedules, may identify FLASH doses that achieve comparable tumor control with less toxicity than CONV. Such findings would encourage clinical trials of FLASH in human BC.

Exfoliated Magnesium Diboride (MgB2) Nanosheets as Solid Fuels

Magnesium diboride (MgB2) has been explored as an alternative fuel to boron (B) due to its high energy density and the additive effect of magnesium (Mg) to promote B combustion. However, the primary oxidation of MgB2 does not occur unless it decomposes at a high temperature (830 °C), which makes ignition difficult and the reaction slow. Recently, two-dimensional (2D) exfoliated MgB2 nanosheets have attracted increasing attention due to their unique properties and potential applications in various fields. In this study, we investigate the potential of 2D exfoliated MgB2 nanosheets as solid fuels for overcoming the challenges of MgB2 combustion. We analyzed their oxidation behavior and energetic performance through material characterization and combustion tests under slow- and fast-heating conditions and compared their performance with those of bulk MgB2, B nanoparticles, and a B/Mg nanoparticle mixture. This study highlights the potential of MgB2 nanosheets as promising solid fuels with superior energetic properties.

The Gcn5-Ada2-Ada3 histone acetyltransferase module has divergent roles in pathogenesis of Candida glabrata

Candida glabrata is an opportunistic fungal pathogen and the second most prevalent species isolated from candidiasis patients. C. glabrata has intrinsic tolerance to antifungal drugs and oxidative stresses and the ability to adhere to mucocutaneous surfaces. However, knowledge about the regulation of its virulence traits is limited. The Spt-Ada-Gcn5 acetyltransferase (SAGA) complex modulates gene transcription by histone acetylation through the histone acetyltransferase (HAT) module comprised of Gcn5-Ada2-Ada3. Previously, we showed that the ada2 mutant was hypervirulent but displayed decreased tolerance to antifungal drugs and cell wall perturbing agents. In this study, we further characterized the functions of Ada3 and Gcn5 in C. glabrata. We found that single, double, or triple deletions of the HAT module, as expected, resulted in a decreased level of acetylation on histone H3 lysine 9 (H3K9) and defective growth. These mutants were more susceptible to antifungal drugs, oxidative stresses, and cell wall perturbing agents compared with the wild-type. In addition, HAT module mutants exhibited enhanced agar invasion and upregulation of adhesin and proteases encoding genes, whereas the biofilm formation of those mutants was impaired. Interestingly, HAT module mutants exhibited enhanced induction of catalases (CTA1) expression upon treatment with H2O2 compared with the wild-type. Lastly, although ada3 and gcn5 exhibited marginal hypervirulence, the HAT double and triple mutants were hypervirulent in a murine model of candidiasis. In conclusion, the HAT module of the SAGA complex plays unique roles in H3K9 acetylation, drug tolerance, oxidative stress response, adherence, and virulence in C. glabrata.

Electrically Driven Hyperbolic Nanophotonic Resonators as High Speed, Spectrally Selective Thermal Radiators

We introduce and experimentally demonstrate electrically driven, spectrally selective thermal emitters based on globally aligned carbon nanotube metamaterials. The self-assembled metamaterial supports a high degree of nanotube ordering, enabling nanoscale ribbons patterned in the metamaterial to function both as Joule-heated incandescent filaments and as infrared hyperbolic resonators imparting spectral selectivity to the thermal radiation. Devices batch-fabricated on a single chip emit polarized thermal radiation with peak wavelengths dictated by their hyperbolic resonances, and their nanoscale heated dimensions yield modulation rates as high as 1 MHz. As a proof of concept, we show that two sets of thermal emitters on the same chip, operating with different peak wavelengths and modulation rates, can be used to sense carbon dioxide with one detector. We anticipate that the combination of batch fabrication, modulation bandwidth, and spectral tuning with chip-based nanotube thermal emitters will enable new modalities in multiplexed infrared sources.

Ultrahigh-Quality Infrared Polaritonic Resonators Based on Bottom-Up-Synthesized van der Waals Nanoribbons

van der Waals nanomaterials supporting phonon polariton quasiparticles possess extraordinary light confinement capabilities, making them ideal systems for molecular sensing, thermal emission, and subwavelength imaging applications, but they require defect-free crystallinity and nanostructured form factors to fully showcase these capabilities. We introduce bottom-up-synthesized α-MoO₃ structures as nanoscale phonon polaritonic systems that feature tailorable morphologies and crystal qualities consistent with bulk single crystals. α-MoO₃ nanoribbons serve as low-loss hyperbolic Fabry-Pérot nanoresonators, and we experimentally map hyperbolic resonances over four Reststrahlen bands spanning the far- and mid-infrared spectral range, including resonance modes beyond the 10th order. The measured quality factors are the highest from phonon polaritonic van der Waals structures to date. We anticipate that bottom-up-synthesized polaritonic van der Waals nanostructures will serve as an enabling high-performance and low-loss platform for infrared optical and optoelectronic applications.

Inorganic Chiral Hybrid Nanostructures for Tailored Chiroptics and Chirality-Dependent Photocatalysis

Inorganic chiral hybrid nanostructures embedding chirality within distinct material compositions can create novel chiral properties and functionalities absent from achiral ones, but remain largely unexplored. We report for the first time a class of chiral plasmonic metal-semiconductor core-shell nanostructures by employing structurally chiral nanoparticles as chirality inducing templates to grow functional shell materials, which allows us to independently control material parameters including core geometry and shell thickness, as well as handedness of the system. We experimentally and theoretically achieve enhanced and tunable chiroptical activity of the hetero-structures as a result of the core-shell strong coupling effect. As a proof-of-concept demonstration, we show the chiral hybrid nanostructures can drive chirality-dependent photocatalytic hydrogen generation under circularly polarized light. This study enables rational design and functionalization of chiral hybrid nanomaterials towards enhanced chiral light-matter interactions and chiral device applications.

Alginate-Capped Silver Nanoparticles as a Potent Anti-mycobacterial Agent Against Mycobacterium tuberculosis

Tuberculosis (TB) is a leading cause of death from a single infectious agent, Mycobacterium tuberculosis (Mtb). Although progress has been made in TB control, still about 10 million people worldwide develop TB annually and 1.5 million die of the disease. The rapid emergence of aggressive, drug-resistant strains and latent infections have caused TB to remain a global health challenge. TB treatments are lengthy and their side effects lead to poor patient compliance, which in turn has contributed to the drug resistance and exacerbated the TB epidemic. The relatively low output of newly approved antibiotics has spurred research interest toward alternative antibacterial molecules such as silver nanoparticles (AgNPs). In the present study, we use the natural biopolymer alginate to serve as a stabilizer and/or reductant to green synthesize AgNPs, which improves their biocompatibility and avoids the use of toxic chemicals. The average size of the alginate-capped AgNPs (ALG-AgNPs) was characterized as nanoscale, and the particles were round in shape. Drug susceptibility tests showed that these ALG-AgNPs are effective against both drug-resistant Mtb strains and dormant Mtb. A bacterial cell-wall permeability assay showed that the anti-mycobacterial action of ALG-AgNPs is mediated through an increase in cell-wall permeability. Notably, the anti-mycobacterial potential of ALG-AgNPs was effective in both zebrafish and mouse TB animal models in vivo. These results suggest that ALG-AgNPs could provide a new therapeutic option to overcome the difficulties of current TB treatments.

[Analysis of gene mutation profile of adult soft tissue sarcomas using high-throughput sequencing technology]

Objective: To understand the genetic variation of soft tissue sarcomas, and to provide a scientific evidence for the individualized treatment. Methods: The somatic mutation and germline mutation of 45 adult soft tissue sarcomas had been detected by high-throughput sequencing technology, the clinical data were also analyzed. Results: A total of 88 gene mutations were detected in 45 samples, including 78 single nucleotide variation (SNV), 13 insertion/deletion (Indel) and 19 copy number variation (CNV). The most common mutant genes are TP53, CDKN2A, MDM2, CDK4, NF1 and PTEN. Among them, the mutation rates of TP53-MDM2/MDM4-CDKN2A pathway, CDKN2A/CDK4/RB1 pathway, and RAS/NF1/PTEN/PI3K pathway were more frequent (32/88, 36%). In terms of immunotherapy biomarkers among 10 samples, the median value of tumor mutation burden was 2.02 muts/Mb (0-4.24 muts/Mb), and all were microsatellite stable. Conclusions: This study analyzes the genetic variation of soft tissue sarcoma, and determines the high-frequency gene mutations and pathways, which may be the potential drug targets. This finding can provide scientific evidences for the personalized treatment of soft tissue sarcoma.

[Association between both maternal and fetal angiotensinogen gene single nucleotide polymorphism and preeclampsia/eclampsia]

Objective: To explore the association between preeclampsia/eclampsia and maternal and fetal angiotensinogen SNPs. Methods: From January 2008 to October 2015, a case-parents/mother-control designed study was conducted among 347 preeclampsia/eclampsia cases and 700 controls to collect related information on their demographic characteristics and to detect the related angiotensinogen SNPs' genotypes. Both log-linear and unconditional logistic regression methods were employed to investigate the genetic effects of maternal/fetal angiotensinogen SNPs on preeclampsia/eclampsia. Multivariate binary unconditional logistic regression model and covariance were used to analyze the relationship between BMI before pregnancy, weight gain during pregnancy and overweight and obesity in preschool children. Results: Both fetal angiotensinogen rs3789679 GA and AA genotype were associated with the reduced risks of preeclampsia/eclampsia, with ORs as 0.73 (95%CI: 0.55-0.96) and 0.62 (95%CI: 0.39-0.98), respectively. For fetal angiotensinogen rs2493132, individuals that carrying the TT genotype, presented a positive association with the risk of preeclampsia/eclampsia, with OR as 1.60 (95%CI: 1.08-2.37). However, these associations were not statistically significant after the correction of the false discovery rate. It was observed that fetal rs3789679 could reduce the risk of preeclampsia/eclampsia (OR=0.73, 95%CI: 0.55-0.96) under the dominant model (GA+AA/GG) while fetal rs2493132 increased the risk of preeclampsia/eclampsia (OR=1.66, 95%CI: 1.13-2.44) under the recessive model (TT/CC+CT). Maternal rs5051 presented an association with preeclampsia/eclampsia (OR=1.33, 95%CI: 1.01-1.76) under the dominant model (TC+CC/TT). Conclusions: Results from the dominant model showed that both fetal rs3789679 GA and AA genotype reduced the risk of preeclampsia/eclampsia and maternal rs5051 TC while CC genotype increased the risk of preeclampsia/eclampsia. Fetal rs2493132 TT genotype seemed to be associated with the risk of preeclampsia/eclampsia under the recessive model.

Prognosis of surgical hernia repair in cirrhotic patients with refractory ascites

BACKGROUND

Abdominal wall hernias are common in patients with ascites. Elective surgical repair is recommended for the treatment of abdominal wall hernias. However, surgical hernia repair in cirrhotic patients with refractory ascites is controversial. In this study, we aimed to evaluate the outcomes of elective surgical hernia repair in patients with liver cirrhosis with and without refractory ascites.

METHOD

From January 2005 to June 2018, we retrospectively reviewed the records of consecutive patients with liver cirrhosis who underwent a surgical hernia repair.

RESULTS

This study included 107 patients; 31 patients (29.0%) had refractory ascites. Preoperatively, cirrhotic patients with refractory ascites had a higher median model for end-stage liver disease (MELD) score (13.0 vs 11.0, P = 0.001) than those without refractory ascites. The 30-day mortality rate (3.2% vs 0%, P = 0.64) and the risk of recurrence (hazard ratio 0.410; 95% CI 0.050-3.220; P = 0.39) did not differ significantly between cirrhotic patients with refractory ascites and cirrhotic patients without refractory ascites. Among cirrhotic patients with refractory ascites, albumin (P = 0.23), bilirubin (P = 0.37), creatinine (P = 0.97), and sodium levels (P = 0.35) did not change significantly after surgery.

CONCLUSION

In advanced liver cirrhosis patients with refractory ascites, hernias can be safely treated with elective surgical repair. Mortality rate within 30 days did not differ by the presence or absence of refractory ascites. Elective hernia repair might be beneficial for treatment of abdominal wall hernia in cirrhotic patients with refractory ascites.

Favorable impact of non-alcoholic fatty liver disease on the cerebral white matter hyperintensity in a neurologically healthy population

BACKGROUND AND PURPOSE

Although non-alcoholic fatty liver disease (NAFLD) shares common cardiovascular risk factors with cerebral white matter hyperintensity (WMH), few studies have reported the association between NAFLD and WMH. The association between the presence of NAFLD with its severity and the volume of WMH was investigated.

METHODS

This cross-sectional study was conducted for 2460 subjects who voluntarily participated in health screening check-ups including brain magnetic resonance imaging and liver ultrasonography at the Health Promotion Center at Seoul National University Hospital from 2009 to 2013. Ultrasonography was used to detect the presence and severity of NAFLD combined with the NAFLD fibrosis score and the FIB-4 index. The volume of WMH was measured using a semi-automated quantification method by a trained neurologist.

RESULTS

The prevalence of NAFLD was 36.5%, and the median volume of WMH in all the subjects was 1.1 ml (interquartile range 0.2-2.7 ml). The presence of NAFLD was associated with a smaller volume of WMH [β (standard error, SE) -0.051 (0.046); P = 0.012]. Moderate to severe NAFLD was associated with a smaller volume of WMH than was non-NAFLD [β (SE) -0.067 (0.061); P = 0.002]. The negative correlation observed between NAFLD severity and WMH volume was persistent only in those with low FIB-4 index and low NAFLD fibrosis scores, whereas there was a positive association in those with high FIB-4 index and NAFLD fibrosis scores.

CONCLUSIONS

Non-alcoholic fatty liver disease, and its severity, showed a favorable association with WMH volume. However, its causality and mechanism should be evaluated in further relevantly designed studies.

Tunable Hyperbolic Metamaterials Based on Self-Assembled Carbon Nanotubes

We show that packed, horizontally aligned films of single-walled carbon nanotubes are hyperbolic metamaterials with ultrasubwavelength unit cells and dynamic tunability. Using Mueller matrix ellipsometry, we characterize the films' optical properties, which are doping level dependent, and find a broadband hyperbolic region tunable in the mid-infrared. To characterize the dispersion of in-plane hyperbolic plasmon modes, we etch the nanotube films into nanoribbons with differing widths and orientations relative to the nanotube axis, and we observe that the hyperbolic modes support strong light localization. An agreement between the experiments and theoretical models using the ellipsometry data indicates that the packed carbon nanotubes support bulk anisotropic responses at the nanoscale. Self-assembled films of carbon nanotubes are well-suited for applications in thermal emission and photodetection, and they serve as model systems for studying light-matter interactions in the deep subwavelength regime.

[A survey on night sleep quality and daytime tiredness among shift nurses in a tertiary teaching hospital]

Objective: To explore the night sleep quality of shift nurses and the current situation of their daytime tiredness, sleepiness, and to provide evidence for nursing administrators and managers to allocate human resources reasonably and prevent adverse events. Methods: The cross-sectional method was utilized to conduct a questionnaire survey among shift nurses in a tertiary teaching hospital in Shandong Province from March to May inclusive, 2017. Results: There was a total of 233 valid questionnaires returned. The prevalence of sleep disorder, daytime tiredness and sleepiness was 45.92%, 16.31% and 13.30%, respectively. The differences of the nurses' sleep quality at night between different ages, marriages, educational backgrounds and professional titles were statistically significant (P<0.05) , while the differences of daytime burnout and sleep state between different shift systems were statistically significant (P<0.01) . Night sleep quality was positively correlated with daytime tiredness and sleepiness (P<0.05) . The results of multiple linear regression analysis showed that age, marriage, educational background and professional title had an impact on nurses' sleep quality at night (P<0.05) . Shift system had an impact on nurses' daytime burnout and sleep apnea (P<0.01) . Conclusion: There was a high prevalence of night sleep disorder, daytime tiredness and sleepiness among the shift nurses. Nursing administrators and managers should pay more attention to the night sleep quality of nurses who aged over 30 years old, married, without a bachelor degree and those with a lower professional rank. Furthermore, the current situation of daytime tiredness and sleepiness among two-shift only nurses was worrisome.

[Genetic and clinical analysis of children with early-onset epilepsy encephalopathy caused by KCNT1 gene mutation]

Objective: To study the mutational characteristics of KCNT1 and its clinical features in children with early-onset epileptic encephalopathy. Methods: Retrospective analysis of clinical data of 175 children with early onset epilepsy from the Department of Pediatrics at Peking University First Hospital from January 2012 to December 2017. Gene-based analysis was performed on children with targeted capture second-generation sequencing and the source of mutations was verified by PCR-Sanger. The clinical features of children with KCNT1 mutation were summarized. Results: In 175 infants with early-onset epileptic encephalopathy, 6 children were found to have KCNT1 mutations, all of which were new mutations with an overall mutation rate of 3.4% (6/175). All the mutations were missense mutations. The age of onset was from 2 days to 32 days. Five children were diagnosed with epilepsy of infancy with migrating focal seizure, one case was diagnosed with epilepsy, focal seizures, focal seizures with generalization. A total of 6 children were treated with multi-antiepileptic drugs. The disease in 4 patients were partially controlled, while in 2 patients, the disease was not significantly alleviated. One patient died of "severe pneumonia" at one year and 4 months of age. Then, four cases were treated with quinidine. The seizure frequency had no change in 3 cases, the frequency decreased and then relapsed in 1 case. The case once ketogenic diet and failed. Ketogenic diet treatment was applied to 5 cases, no significant effect was achieved. All the 6 patients had severe developmental delay. They could not sit alone, follow the light and objects and had no language. Conclusions: The mutation of KCNT1 gene is mainly de novo. The onset of the disease was early, and mostly occurs in neonate and early infancy. The main seizure type was epilepsy of infancy with migrating focal seizure. Patients usually had severe psychomotor developmental delay. Antiepileptic drugs are ineffective. The efficacy of quinidine was not significant. Though, it still need studies on a large sample.

Comparison of overall survival between antiviral-induced viral suppression and inactive phase chronic hepatitis B patients

Nucleot(s)ide analogues (NAs) reduce the risk of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients. However, the risk of HCC is reportedly higher for NA-treated patients than for patients in the inactive CHB phase. This study aimed to compare the long-term outcomes of CHB patients with NA-induced viral suppression and those of patients with inactive CHB. This retrospective study involved 1118 consecutive CHB patients whose HBV DNA level was continuously <2000 IU/mL during follow-up with/without antiviral agents. The patients were classified into inactive CHB (n = 373) or NA groups (n = 745). The primary endpoint was overall survival. Secondary endpoints included development of HCC and other liver-related events. The median duration of follow-up was 41.0 (interquartile range = 26.5-55.0) months. The difference in overall survival between the NA group vs. the inactive CHB group was not significant (hazard ratio [HR] = 0.78; 95% confidence interval [CI] = 0.33-1.85; P = .57). The NA group showed a significantly higher risk of HCC (HR = 3.44; 95% CI = 1.82-6.52; P < .01), but comparable risk for non-HCC liver-related events (HR = 1.02; 95% CI = 0.66-1.59; P = .93), compared with the inactive CHB group. Among patients with cirrhosis, the NA group showed a significantly lower risk of death (HR = 0.31; 95% CI = 0.097-0.998; P = .05) and non-HCC liver-related events (HR = 0.51; 95% CI = 0.31-0.83; P < .01), but a slightly higher risk of HCC (HR = 2.39; 95% CI = 0.85-6.75; P = .09), compared to the inactive CHB group. The overall survival of untreated patients with inactive CHB and of CHB patients achieving viral suppression with NA was comparable. However, NA treatment of cirrhotic patients was significantly associated with longer overall survival and lower risk of liver-related events.

[Analysis of clinicopathological characteristics and prognostic factors of foot and ankle soft tissue and bone tumors]

Objective: To evaluate the clinicopathological characteristics of foot and ankle soft tissue and bone tumor, and to analyze the prognosis and the related factors of malignant tumors in this site. Methods: 74 patients with soft tissue and bone tumors of foot and ankle from January 2006 to February 2017 were retrospectively analyzed. The clinicopathological characteristics, the treatment and survival status of malignant tumors were followed up, and the clinical and therapeutic factors related to prognosis were analyzed. Results: Of the 74 patients, 34 were males and 40 were females. The male to female ratio was 1∶1.18; the age ranged from 12 to 64 years and the median age was 42 years. Tumors located in forefoot of 22 cases, 22 in midfoot, 10 in hind foot, 14 in ankle joint and 6 in multiple sites. 14 cases were bone tumors, including 7 benign and 7 malignant, and 60 cases were soft tissue tumors, including 14 benign and 46 malignant. The most common malignant soft tissue tumors were synovial sarcomas (13 cases), and the most common benign soft tissue tumors were hemangiomas (4 cases). 44 cases of malignant tumors underwent surgery were followed up, of which were 7 bone and 37 soft tissue malignant tumors. Limb salvage surgeries were performed in 33 cases and amputation in 11 cases. The median follow-up time was 69.8 months, and the median survival time was 40.7 months. The 1-year, 3-year and 5-year survival rate of soft tissue malignant tumors was 88.0%, 73.0%, and 63.0%, respectively. The 1-year, 3-year and 5-year survival rate of bone malignant tumors was 86.0%, 57.0% and 57.0%, respectively. Univariate analysis showed that the prognostic factors affecting 5-year survival rate were tumor size and adjuvant therapy (P<0.05). Patient's gender, age, tumor location, histological type and surgical procedure had no effect on overall survival(P>0.05). Multivariate analysis showed that tumor size was an independent prognostic factor (RR=7.262, P=0.005). Conclusions: Forefoot and midfoot are more common in foot and ankle soft tissue and bone tumors. Synovial sarcoma is the most common diagnosis in malignant soft tissue tumors, and hemangioma is the most common diagnosis in benign soft tissue tumors. The prognostic factor of malignant soft tissue and bone tumors in foot and ankle is tumor size. Patients with the tumor size of 5 cm or more have a worse prognosis.

Protein kinase A governs growth and virulence in Candida tropicalis

Candida tropicalis is one of the most important human fungal pathogens causing superficial infections in locations such as the oral mucosa and genital tract, as well as systemic infections with high mortality. In its sister species Candida albicans, the cyclic AMP/protein kinase A (cAMP/PKA) pathway regulates fungal adhesion and dimorphism, both of which correlate closely with virulence. CaTpk1 and CaTpk2, the catalytic subunits of PKA, not only share redundant functions in hyphal growth, adhesion, and biofilm formation, but also have distinct roles in stress responses and pathogenesis, respectively. However, studies on PKA in the emerging fungal pathogen C. tropicalis are limited. Our results suggest that Tpk1 is involved in cell wall integrity and drug tolerance. The tpk2/tpk2 mutants, which have no protein kinase A activity, have reduced hyphal growth and adhesion. In addition, the tpk1/tpk1 tpk2/tpk2 double deletion mutant demonstrated delayed growth and impaired hyphal formation. In a murine model of systemic infection, both TPK1 and TPK2 were required for full virulence. We further found that EFG1 and HWP1 expression is regulated by PKA, while BCR1, FLO8, GAL4, and RIM101 are upregulated in the tpk1/tpk1 tpk2/tpk2 mutant. This study demonstrates that Tpk1 is involved in drug tolerance and cell wall integrity, while Tpk2 serves as a key regulator in dimorphism and adhesion. Both Tpk1 and Tpk2 are required for growth and full virulence in C. tropicalis.

[Comparison of effects of oleic acid and palmitic acid on lipid deposition and mTOR / S6K1 / SREBP-1c pathway in HepG2 cells]

Objective: To explore the effects of oleic acid and palmitic acid on lipid deposition and mTOR/S6K1/SREBP-1c pathways in HepG2 cells. Methods: The model of steatosis was established with induction of oleic acid and palmitic acid and was intervened by rapamycin. The changes in lipid droplets were observed after staining the cells with oil Red O. Intracellular triglyceride (TG) contents in cells were measured by TG kit. mTOR, S6K1, and SREBP-1c mRNA expression levels were detected using QRT-PCR. Western blot was used to determine protein expression levels of mTOR, S6K1 and SREBP-1c. Results: Both fatty acids increased lipid droplets in HepG2 cells. Fatty degeneration with elevated TG occurred with significant changes in oleic acid group lipids. Rapamycin alleviated lipid deposition caused by oleic acid and palmitic acid and inhibited their induction of increased expression of mTOR, S6K1, and SREBP-1c. QRT-PCR and Western blot results showed that mRNA and protein expressions of mTOR, S6K1, and SREBP-1c in oleic acid and palmitic acid group were significantly higher than the control group (P < 0.05). The increase was more pronounced in the palmitic acid group (P < 0.05); however, after rapamycin intervention, the expression of mRNA and protein in the three groups were significantly lower (P < 0.05), and the change in palmitic acid group was more pronounced (P < 0.05). Conclusion: Oleic acid and palmitic acid can induce lipid deposition in HepG2 cells and increase expression of every component of mTOR/S6K1/SREBP-1c pathway; however, Oleic acid-induced lipid deposition is more pronounced, and the mTOR, S6K1, and SREBP-1c pathway change is more obvious in palmitic acid. Rapamycin has high potent inhibitory effect on palmitic acid-induced lipid deposition. These results specify that lipid synthesis involved in the mTOR/S6K1/SREBP-1c pathways are mainly associated to palmitic acid in HepG2 cells, whereas other signaling pathway may mediate oleic acid-induced lipid synthesis.

Entecavir and tenofovir reduce hepatitis B virus-related hepatocellular carcinoma recurrence more effectively than other antivirals

Nucleos(t)ide analogues (NAs) have been shown to decrease the risk of hepatocellular carcinoma (HCC) recurrence. This study evaluated whether high-potency NAs (entecavir and tenofovir disoproxil fumarate [TDF]) reduce the risk of tumour recurrence more potently than low-potency NAs after curative treatment of hepatitis B virus (HBV)-related HCC. This study included 607 consecutive HBV-related HCC patients treated with surgical resection or radiofrequency ablation. The patients were categorized into three groups according to antiviral treatment: group A (no antiviral; n = 261), group B (low-potency NA; n = 90) and group C (high-potency NA; n = 256). The primary end-point was recurrence-free survival (RFS). During the duration of follow-up, the median RFS was 29.4, 25.1, and 88.2 months in groups A, B and C, respectively (P < .001, log-rank test). The multivariate Cox analysis indicated that group C had a significantly longer RFS than both group A (adjusted hazard ratio [HR] = 0.39, P < .001) and group B (adjusted HR = 0.47, P < .001). When baseline characteristics were balanced using inverse probability weighting, group C still had a significantly longer RFS than group A (adjusted HR = 0.46, P < .001) and group B (adjusted HR = 0.59, P = .007). Group C had significantly lower risk of viral breakthrough than group B (HR = 0.19, P < .001). Viral breakthrough was an independent risk factor for shorter RFS among groups B and C (adjusted HR = 2.03, P = .007, time-dependent Cox analysis). Antiviral agents with high genetic barrier to resistance (entecavir and TDF) reduced the risk of HCC recurrence compared with other antivirals and no antiviral treatment, especially in patients with high baseline viral load.

Intensity of surveillance for hepatocellular carcinoma determines survival in patients at risk in a hepatitis B-endemic area

BACKGROUND

Data are insufficient regarding the survival benefit of surveillance for hepatocellular carcinoma (HCC).

AIM

To investigate the effectiveness of HCC surveillance in a hepatitis B-endemic population.

METHODS

This retrospective cohort study included 1402 consecutive patients who were newly diagnosed with HCC between 2005 and 2012 at a single tertiary hospital in Korea. The primary endpoint was overall survival. Lead-time and length-time biases were adjusted (sojourn time = 140 days) and sensitivity analyses were performed.

RESULTS

The most common aetiology was hepatitis B (80.4%). Cirrhosis was present in 78.2%. HCC was diagnosed during regular surveillance (defined as mean interval of ultrasonography <8 months, n = 834), irregular surveillance (n = 104) or nonsurveillance (n = 464). Patients in the regular surveillance group were diagnosed at earlier stages ([very] early stage, 64.4%) than the irregular surveillance (40.4%) or nonsurveillance (26.9%) groups and had more chance for curative treatments (52.4%) than the irregular surveillance (39.4%) or nonsurveillance (23.3%) groups (all P < 0.001). Mortality risk was significantly lower in the regular surveillance group (adjusted hazard ratio [aHR], 0.69; 95% [CI], 0.57-0.83) but not in the irregular surveillance group (aHR, 0.94; 95% CI, 0.69-1.28) compared with the nonsurveillance group after adjusting for confounding factors and lead-time. When the subjects were restricted to cirrhotic patients or Child-Pugh class A/B patients, similar results were obtained for mortality risk reduction between groups.

CONCLUSIONS

HCC surveillance was associated with longer survival owing to earlier diagnosis and curative treatment. Survival advantage was significant with regular surveillance but not with irregular surveillance.

[The role of preoperative (18)F-FDG PET-CT in lymphatic metastasis diagnosis of cutaneous malignant melanoma on extremities and trunk]

Objective: To evaluate the clinical value of preoperative (18)F-Fludeoxyglucose ((18)F-FDG PET-CT) in lymphatic metastasis diagnosis of cutaneous melanoma on extremities and trunk. Methods: 112 patients with cutaneous melanoma pathologically of extremities and trunk from January 2006 to December 2016, who received (18)F-FDG PET-CT examination preoperatively, were retrospectively reviewed. The correlations between the maximal diameters of lymph nodes, the maximal standard uptake value (SUV) and the diagnostic impression grades of PET-CT examination, and the final pathological diagnosis were analyzed. The correlations between Breslow thickness of primary lesions and the diagnostic impression of PET-CT examination were also analyzed. All the above were analyzed with Receiver Operating Characteristic (ROC) curve to get the cut-off value. Based on the final results of pathological diagnosis of lymph nodes as the golden standard, the statistically significant indicators of ROC curve analysis were used to evaluate the diagnostic effect, as well as to calculate the sensitivity, specificity and accuracy. With gender, age, maximal diameter of lymph nodes, maximal SUV, diagnosis impressions, and Breslow thickness as the independent variables and pathological diagnosis results of lymph nodes as the dependent variable, two-class stepwise Logistic regression analysis was used to determine the independence of diagnostic indicators. ROC curve analysis and log rank test were used to analyze the relationship between Breslow thickness and patient survival. Results: To evaluate melanoma patients' lymph node status, the results of ROC curve analysis showed that the area under the curve of lymph node maximal diameter, maximal SUV, diagnosis impression of PET-CT examinations were 0.789, 0.786 and 0.816, respectively (all P<0.05). The cut-off values were 0.85 cm, 1.45 and 2.5, respectively. The sensitivity of the cut-off values to determine the status of lymph nodes in melanoma patients were 71.4%, 64.9% and 72.1% respectively, and the specificities were 85.2%, 88.7% and 87.0% respectively. Multivariate Logistic regression analysis showed that PET-CT diagnosis impressions had independent diagnostic significance for the lymph node status of melanoma patients (OR=11.296, 95%CI: 2.550~50.033). The area under the curve of Breslow thickness evaluating PET-CT diagnostic impression is 0.664 (P=0.042) and the cut-off value was 4.25 mm. The survival rate of the patients with Breslow thickness ≥ 4.25 mm was lower than that in the group <4.25 mm (P=0.006). Conclusions: (18)F-FDG PET-CT can help to evaluate metastases and make treatment decisions for cutaneous melanoma of extremities and trunk, especially for patients whose primary lesion's Breslow thickness has reached more than 4.25 mm. For the patients whose maximal SUV of regional lymph node is higher than 1.45 and short diameter of the largest lymph node is larger than 0.85cm, the possibility of metastases should be considered.

Delayed viral suppression during antiviral therapy is associated with increased hepatocellular carcinoma rates in HBeAg-positive high viral load chronic hepatitis B

The treatment option in chronic hepatitis B (CHB) patients with persistent low-level viremia despite entecavir or tenofovir monotherapy is unclear. This study investigated the development of hepatocellular carcinoma (HCC) or cirrhosis in hepatitis B e antigen (HBeAg)-positive high viral load CHB patients, according to the time needed to achieve complete viral suppression. A total of 325 HBeAg-positive CHB patients with high viral load who were recently started on antiviral therapy with entecavir or tenofovir were included. The enrolled patients were divided into 2 groups with 4 separate criteria based on the time needed to achieve complete viral suppression: within 1, 2, 3 or 4 years of therapy initiation. The outcomes were development of HCC and cirrhosis. The cumulative incidence of HCC was significantly higher in patients failing complete viral suppression within 1 year (hazard ratio (HR), 4.54; 95% confidence interval (CI), 1.03-19.93; P = .045) or 2 years (HR, 3.38; 95% CI, 1.24-9.23; P = .018), than patients who achieved complete viral suppression within 1 or 2 years, respectively. Cumulative incidence of cirrhosis was also significantly higher in patients failing suppression within 1 year (HR, 1.95; 95% CI, 1.04-3.66; P = .037) or 2 years (HR, 2.44; 95% CI, 1.41-4.22; P = .001). When the time for achieving viral suppression exceeded 2 years, the cumulative incidence of HCC or cirrhosis was not different regardless of viral suppression. Complete hepatitis B virus suppression within 2 years of antiviral therapy initiation is associated with risk reduction in HCC or cirrhosis development.

[Reliability and validity of the simplified Chinese version of the fecal incontinence quality of life questionnaire in the patients with fecal incontinence]

Objective: To develop the Chinese version of the fecal incontinence quality of life (FIQL) questionnaire, and to validate them in Chinese population. Methods: Our study included 52 cases recruiting from outpatients diagnosed with fecal incontinence in Peking Union Medical College Hospital, fecal incontinence in Beijing City nursing homes for the elderly, and patients received perineal repair surgeries who suffered from perineal laceration and laceration in in Peking Union Medical College Hospital from October 2013 to 2016 December.The Original English Fecal Incontinence Quality of Life scale questionnaires were translated into Chinese and they were linguistically validated following the Cross-cultural adaptation of health-related quality of life measures.The reliability and validity of the Chinese version of FIQL questionnaires in Chinese population were evaluated. Results: Fifty-two patients completed the FIQL and the SF-12 questionnaires, as well as Cleveland Clinic Incontinence Score.The Cronbach's alpha of FIQL was 0.949, test-retest reliability ICC was 0.437-0.866. FIQL scores were positively correlated with SF-12 (Spearman correlation coefficient was 0.588, P<0.01) and negatively correlated with Cleveland Clinic Incontinence Score (Spearman correlation coefficient was -0.617, P<0.01). Factor analysis showed that there were 6 common factors in FIQL. Conclusions: Chinese version of FIQL have high reliability and validity in Chinese population, there fore it is suitable for clinic and research.

Coherent Discriminatory Modal Manipulation of Acoustic Phonons at the Nanoscale

Understanding and controlling the phononic characteristics in solids is crucial to elucidate many physical phenomena and develop new phononic devices with optimal performance. Although substantial progress on the spatial control of phonons by material design has been achieved, the manipulation of phonons in the time domain has been less studied but can elucidate in-depth insight into various phonon-coupling processes. In this work, we explore different time-domain pump-control(s)-probe phonon manipulation schemes in both simulations and experiments with good consistency. In particular, we use an Au-Ag core-shell nanoparticle with a manifestation of multiple phonon vibrational modes as a model system for multimodal-phonon manipulation, and we demonstrate that the simple addition of a femtosecond optical control pulse to an all-optical pump-probe phonon measurement can enhance or suppress the fundamental breathing phonon mode of nanoparticles depending on the time separation between the pump and the control pulses. A more advanced control of the higher-order phonon modes and their interplay has also been achieved using two sequential and independently tunable optical control pulses, which enables the discriminatory modal manipulation of phonons for the first time. This work represents a significant step toward a deep understanding of the phonon-mediated physical and chemical processes and a development of new nanoscale materials with desirable functionalities and properties.

[Selective preimplantation pathological evaluation in renal transplantation: a single center's experience]

Objective: To summarize the clinical data of pre-implantation biopsy donors in our hospital and explore the clinical characteristics of those donors in pathological high-risk, and to provide references for the selective histological evaluation of extended criteria donor kidneys. Methods: We retrospectively reviewed the clinical data and pre-implantation renal pathologic score of donors from January 1, 2015 to May 1, 2017.During this period, 247 cases of donation after citizen's death (DCD) occurred.After clinical evaluation and selective machine perfusion( Lifeport) evaluation, 30 cases of pre-implantation pathological evaluation were performed.According to Remuzzi scores, donors were divided into low-risk and high-risk group.Nine cases of low-risk group (bilateral kidney's Remuzzi score ≤3) and 16 cases of high-risk group (bilateral or unilateral kidney's Remuzzi score ≥4, severe glomerular micro-thrombi or severe tubular necrosis) were included.Five cases of donors were excluded due to only unilateral renal pathological result available.Both high-risk and low-risk groups' clinical data, including sex, age, height, body weight, body mass index, proteinuria, hematuria, urinary glucose, baseline or admission serum creatinine, serum creatinine before procurement, history of hypertension and/or diabetes mellitus, cardiopulmonary resuscitation or not, with or without the history of shock, urine output prior to acquisition, macroscopical manifestations of donor kidney, cause of death were statistically analyzed. Results: The donors' baseline serum creatinine/upper limit of normal serum creatinine range in high-risk group were significantly higher than that in low-risk group [(129.8±42.2)% vs(92.4±30.5)%, P=0.029]. The poor macroscopical manifestations of donor kidneys were significantly more frequent in high-risk group than that in low-risk group (12/16 vs 0/9, P= 0). No significant differences between two groups were found regarding their age, height, weight, BMI, proteinuria, hematuria, urine glucose, pre-procure creatinine level, history of hypertension and/or diabetes mellitus, cause of death and so on (P>0.05). Conclusions: After clinical evaluation and selective Lifeport evaluation, donor grafts of whose baseline serum creatinine levels increased beyond normal range and of whose grafts' macroscopical manifestations were poor, should undergo pre-implantation pathological evaluation further.Also, it is reasonable to perform pre-implantation biopsy in cases of equivocal results after Lifeport evaluation.This will be beneficial to identify histological high-risk donors and also be predictive to allocate the grafts.

Rifaximin treatment is associated with reduced risk of cirrhotic complications and prolonged overall survival in patients experiencing hepatic encephalopathy

BACKGROUND

Rifaximin might decrease the risk of portal hypertension-related complications by controlling small intestinal bacterial overgrowth.

AIM

To evaluate whether rifaximin was associated with the risk of death and cirrhotic complications.

METHODS

We conducted a retrospective study that included 1042 patients experiencing hepatic encephalopathy (HE): 421 patients without hepatocellular carcinoma (HCC; the non-HCC cohort) and 621 patients with HCC (the HCC cohort). The primary endpoint was overall survival and secondary endpoints were recurrence of HE and the development of spontaneous bacterial peritonitis (SBP), hepatorenal syndrome (HRS) and variceal bleeding.

RESULTS

In the non-HCC cohort, 145 patients received rifaximin plus lactulose (the rifaximin group) and 276 patients received lactulose alone (the control group). The multivariate analysis revealed that rifaximin was significantly associated with lower risk of death (adjusted hazard ratio [aHR], 0.697; P = .024) and reduced the risk of recurrent HE (aHR, 0.452; P < .001), SBP (aHR, 0.210; P < .001) and variceal bleeding (aHR, 0.425; P = .011) but not HRS (aHR, 0.598; P = .08). In the HCC cohort, 173 patients received rifaximin plus lactulose and 448 patients received lactulose. Rifaximin was not associated with the risk of death (aHR, 1.177; P = .121). Rifaximin was associated with lower risk of SBP (aHR, 0.323; P < .001) but not with variceal bleeding (aHR, 0.660; P = .104) or recurrent HE (aHR, 0.689; P = .057). The risk of Clostridium difficile-associated diarrhoea was not different between the groups (aHR, 0.028; P = .338).

CONCLUSIONS

In patients without HCC, rifaximin treatment was significantly associated with prolonged overall survival and reduced risks of spontaneous bacterial peritonitis, variceal bleeding and recurrent hepatic encephalopathy.

[Clinicopathological features and prognosis of malignant peripheral nerve sheath tumor: a retrospective study of 140 cases]

Objective: To investigate the clinicopathological features and prognosis of malignant peripheral nerve sheath tumors (MPNST). Methods: We retrospectively reviewed the clinical data of MPNST patients who were treated at Cancer Institute & Hospital, Chinese Academy of Medical Science from January 1999 to January 2016. A total of 140 patients with 66 male and 74 female with MPNST were enrolled in the study. The median age was 40 at the time of diagnosis. Survival analysis were estimated by Kaplan-Meier method and Log rank test. Multivariate analysis were estimated by Cox proportional hazards regression model. Results: The median follow-up time was 43.0 months. The 3- and 5-year overall survival (OS) rates were 56.4% and 48.6%, respectively. The 3-year local recurrence (LR) rate and distant metastasis (DM) rates were 42.9% and 49.3%, respectively. Univariate analysis showed that the tumor location, AJCC stage, S-100, radiotherapy and margin status affected 5-year OS rate (all P<0.05). The tumor location, AJCC stage, S-100, Ki-67 staining, margin status, radiotherapy and chemotherapy affected 3-year LR rate (all P<0.05). The tumor location, AJCC stage, S-100, Ki-67 staining and margin status affected 3-year DM rate (all P<0.05). Multivariate analysis showed that the tumor location, AJCC stage, S-100 were independent factors for 5-year OS rate (all P<0.05). The tumor location, Ki-67 staining and chemotherapy were independent factors for LR (all P<0.05) while the AJCC stage, margin status and Ki-67 staining were independent factors for DM (all P<0.05). Conclusions: MPSNT is an aggressive tumor with poor prognosis. Multiple factors were identified in this study. Patients with the tumor located at head and neck, advanced AJCC stage and negative S-100 usually have a low 5-year overall survival rate. Patients with the tumor located at head and neck, Ki-67 staining ≥ 20% and without chemotherapy had a higher tendency of local recurrence. Poor prognosis factors for DM were advanced AJCC stage, positive margin and Ki-67 staining ≥ 20%.

Cooperative expression of atomic chirality in inorganic nanostructures

Cooperative chirality phenomena extensively exist in biomolecular and organic systems via intra- and inter-molecular interactions, but study of inorganic materials has been lacking. Here we report, experimentally and theoretically, cooperative chirality in colloidal cinnabar mercury sulfide nanocrystals that originates from chirality interplay between the crystallographic lattice and geometric morphology at different length scales. A two-step synthetic scheme is developed to allow control of critical parameters of these two types of handedness, resulting in different chiral interplays expressed as observables through materials engineering. Furthermore, we adopt an electromagnetic model with the finite element method to elucidate cooperative chirality in inorganic systems, showing excellent agreement with experimental results. Our study enables an emerging class of nanostructures with tailored cooperative chirality that is vital for fundamental understanding of nanoscale chirality as well as technology applications based on new chiroptical building blocks.

Anakinra Protects Against Serum Deprivation-Induced Inflammation and Functional Derangement in Islets Isolated From Nonhuman Primates

We investigated whether serum deprivation induces islet amyloid polypeptide (IAPP) oligomer accumulation and/or a proinflammatory response and, if so, whether the addition of interleukin (IL)-1 receptor antagonist to the culture medium can relieve the proinflammatory response during serum-deprived culture of nonhuman primate (NHP) islets. After culture in medium with and without Ana under serum-deprived culture conditions, IAPP oligomer/amyloid accumulation, in vitro viability, islet function, cytokine secretion, and posttransplantation outcome in streptozotocin-induced diabetic nude mice were determined in islets isolated from heterozygote human IAPP transgenic (hIAPP^+/- ) mice and/or NHP islets. Serum deprivation induced accumulation of IAPP oligomer, but not amyloid, in NHP islets. Anakinra (Ana) protected islets from the serum deprivation-induced impairment of in vitro viability and glucose-stimulated insulin secretion and attenuated serum deprivation-induced caspase-1 activation, transcription, and secretion of IL-1β, IL-6, and tumor necrosis factor-α in hIAPP^+/- mice and NHP islets. Supplementation of medium with Ana during serum-deprived culture also improved posttransplantation in vivo outcomes of NHP islets. In conclusion, serum deprivation induced accumulation of IAPP oligomers and proinflammatory responses in cultured isolated islets. Supplementation of the culture medium with Ana attenuated the functional impairment and proinflammatory responses induced by serum deprivation in ex vivo culture of NHP islets.

New facets of antifungal therapy

Invasive fungal infections remain a major cause of morbidity and mortality in immunocompromised patients, and such infections are a substantial burden to healthcare systems around the world. However, the clinically available armamentarium for invasive fungal diseases is limited to 3 main classes (i.e., polyenes, triazoles, and echinocandins), and each has defined limitations related to spectrum of activity, development of resistance, and toxicity. Further, current antifungal therapies are hampered by limited clinical efficacy, high rates of toxicity, and significant variability in pharmacokinetic properties. New antifungal agents, new formulations, and novel combination regimens may improve the care of patients in the future by providing improved strategies to combat challenges associated with currently available antifungal agents. Likewise, therapeutic drug monitoring may be helpful, but its present use remains controversial due to the lack of available data. This article discusses new facets of antifungal therapy with a focus on new antifungal formulations and the synergistic effects between drugs used in combination therapy.

Association between the CYP11B2 gene -344T>C polymorphism and coronary artery disease: a meta-analysis

Numerous studies have evaluated the association between the CYP11B2 gene -344T>C polymorphism and coronary artery disease (CAD) risk. However, the specific association is still controversial. To address this issue, PubMed, EMBASE, and China National Knowledge Infrastructure databases were searched for eligible articles that reported on the relationship between the CYP11B2 gene -344T>C polymorphism and CAD, and were published before April 2014. Data from five separate studies with 3687 subjects were analyzed by meta-analysis. No significant variation in CAD risk was detected by any of the genetic models in the overall study population. Taking into account the effect of ethnicity, further stratified analyses demonstrated significant association in both Caucasian (TT vs TC: OR = 0.80, 95%CI = 0.64-1.00) and Asian populations (TT vs TC: OR = 1.25, 95%CI = 1.01-1.54; dominant model: OR = 0.80, 95%CI = 0.66-0.98). The pooled ORs were not substantially altered after the exclusion of one study in the control group that deviated from Hardy-Weinberg equilibrium, highlighting the reliability of our meta-analysis results. In conclusion, this meta-analysis suggested that the -344T>C polymorphism in the CYP11B2 gene might be associated with susceptibility to CAD in Caucasians and Asians.

Candida albicans OPI1 regulates filamentous growth and virulence in vaginal infections, but not inositol biosynthesis

ScOpi1p is a well-characterized transcriptional repressor and master regulator of inositol and phospholipid biosynthetic genes in the baker’s yeast Saccharomyces cerevisiae. An ortholog has been shown to perform a similar function in the pathogenic fungus Candida glabrata, but with the distinction that CgOpi1p is essential for growth in this organism. However, in the more distantly related yeast Yarrowia lipolytica, the OPI1 homolog was not found to regulate inositol biosynthesis, but alkane oxidation. In Candida albicans, the most common cause of human candidiasis, its Opi1p homolog, CaOpi1p, has been shown to complement a S. cerevisiae opi1∆ mutant for inositol biosynthesis regulation when heterologously expressed, suggesting it might serve a similar role in this pathogen. This was tested in the pathogen directly in this report by disrupting the OPI1 homolog and examining its phenotypes. It was discovered that the OPI1 homolog does not regulate INO1 expression in C. albicans, but it does control SAP2 expression in response to bovine serum albumin containing media. Meanwhile, we found that CaOpi1 represses filamentous growth at lower temperatures (30°C) on agar, but not in liquid media. Although, the mutant does not affect virulence in a mouse model of systemic infection, it does affect virulence in a rat model of vaginitis. This may be because Opi1p regulates expression of the SAP2 protease, which is required for rat vaginal infections.

Association of a microRNA-323b polymorphism with the persistence of hepatitis B virus infection by the enhancement of viral replication

Recent studies have shown that some mammalian microRNAs (miRNAs) play a role in antiviral defence. However, little is known about the role of miRNA-323b in hepatitis B virus (HBV)-host interaction. We explored whether single nucleotide polymorphism (SNP) of miRNA-323b affects HBV replication in a Korean HBV cohort. Genotyping was performed in a total of 1439 subjects composed of 404 spontaneously recovered (SR) subjects as normal controls and 1035 chronic carriers (CC) of HBV who were further classified into 313 patients with chronic hepatitis, 305 patients with liver cirrhosis and 417 patients with hepatocellular carcinoma. To confirm the effect of SNP of miRNA-323b on HBV replication in vitro, HepAD38 cells were transfected with miRNA-323b wild type or miRNA-323b SNP plasmid vectors, and HBV replication was induced for 5 days. HBV DNA was isolated and quantified using real-time PCR. The polymorphism rs56103835C>T in the pre-miRNA region of miRNA-323b revealed significant minor allele frequency (0.273). rs56103835C>T SNP showed significantly affect persistence of HBV in CC group compared with SR group (OR = 1.29, P = 0.009 in a codominant model; OR = 1.29, P = 0.03 in a dominant model; and OR = 1.78, P = 0.03 in a recessive model). In vitro, the total intracellular HBV DNA content was significantly reduced by miRNA-323b wild-type plasmid vector transfection (P = 0.014). The polymorphism of miRNA-323b was significantly associated with persistence of HBV by the enhancement of HBV replication (P = 0.021). Our findings provide a novel perspective on the role SNP of miRNAs in host-virus interactions in HBV infection.

Telbivudine protects renal function in patients with chronic hepatitis B infection in conjunction with adefovir-based combination therapy

Previous studies have demonstrated that the treatment of chronic hepatitis B (CHB) infection with adefovir (ADV) can impair renal function. In contrast, treatment with telbivudine (LdT) improves renal function in CHB patients. The aim of this study was to evaluate the renoprotective effect of LdT in CHB patients receiving ADV-based combination therapy. The effects of treatment with ADV + LdT on renal function were compared to those resulting from treatment with ADV + entecavir (ETV), ADV + lamivudine (LAM), ADV alone and ETV alone. The consecutive cohort analysis included 831 CHB patients who received ADV + LdT, ADV + LAM, ADV + ETV, ADV alone or ETV alone for 96 weeks. Alterations in estimated glomerular filtration rate (eGFR) were compared between the five groups using a linear mixed-effects model. HBV DNA levels were also compared between the five groups during the 96-week period. Among the five treatment groups, significant improvements in eGFR were observed in the ADV + LdT and ADV + LAM groups over time (P < 0.001 for each group compared with baseline eGFR). In patients with a baseline eGFR between 50 and 90 mL/min, the change in eGFR was the most significant in the ADV + LdT group (+0.641 mL/min; P < 0.001). Age, gender, baseline eGFR and treatment option were significant predictive factors for eGFR changes. In conclusion, our results suggest that the combination therapy of LdT and ADV is significantly associated with renoprotective effects in CHB patients when compared with other ADV-based combination or single therapies.

Relationship between polymorphisms near the IL28B gene and spontaneous HBsAg seroclearance: a systematic review and meta-analysis

Polymorphisms near the interleukin (IL) 28B gene have been proposed to be associated with spontaneous clearance of the hepatitis C virus. The purpose of this study was to assess the relationship between IL28B polymorphisms and the rate of spontaneous hepatitis B surface antigen (HBsAg) seroclearance by means of meta-analysis. MEDLINE/PubMed and EMBASE were utilized to identify relevant studies. Odds ratio (OR) and 95% confidence interval (CI) were analysed together to assess the strength of the association. Subgroup analyses were mainly performed according to ethnicity. A total of 4028 cases with persistent chronic hepatitis B and 2327 spontaneously recovered controls were included from 11 studies. The single nucleotide polymorphism (SNP), rs12979860, had no significant association with HBsAg seroclearance (OR = 0.98, 95% CI: 0.84-1.14 in the dominant model; OR = 1.00, 95% CI: 0.68-1.46 in the recessive model; and OR = 0.95, 95% CI: 0.82-1.09 in the allelic model). The SNP, rs12980275, had no significant association either (OR = 1.03, 95% CI: 0.84-1.26 in the dominant model; OR = 1.17, 95% CI: 0.46-2.96 in the recessive model; and OR = 1.04, 95% CI: 0.86-1.26 in the allelic model), nor did the SNP, rs8099917 (OR = 0.94, 95% CI: 0.77-1.15 in the dominant model; OR = 0.74, 95% CI: 0.34-1.62 in the recessive model; and OR = 0.93, 95% CI: 0.77-1.13 in the allelic model). Similarly, the results of subgroup analyses by ethnicity also showed no association in either the Asian group or non-Asian group. We concluded that there was no significant association between common IL28B polymorphisms and the rate of spontaneous HBsAg seroclearance.

P3-17-08: Macroautophagy Protects Breast Cancer MCF-7 Cells from TAM-Induced Apoptosis Via Mitogen-Activated Protein Kinase (MAPK) Pathway

Tamoxifen (TAM) has been used ubiquitously for endocrine therapy for the hormone-sensitive breast cancer. Several studies have revealed that tamoxifen treatment induced apoptosis and at the same time tamoxifen increased autophagic levels in MCF-7 cells. The previous studies attempt to elaborate the significance and mechanism of autophagy induced by TAM in breast cancer cells, however, there are contradictions among their conclusions, it is still not clear that autophagy protects MCF-7 from apoptosis or promotes apoptosis. Better understanding of the effect of autophagy induced by TAM in breast cancer cells on apoptosis will be of the important clinical significance in endocrine therapy for breast cancer.

The present study shows that tamoxifen treatment significantly increased autophagic levels by inducing autophagic vacuoles formation in MCF-7 cells observed by means of transmission electron microscopy and enhancing the expression of autophagy marker, icrotubule-associated protein light chain 3 measured by Western blot. Our research shows tamoxifen enhanced the phosphorylation of MAPKs when inducing autophagy and autophagy decreased significantly when kinase inhibitors were separately used to inhibit the phosphorylation of ERK, JNK, p38 MAPK. MAPK signal transduction pathway was involved in the process of autophagy in MCF-7 cells.

To investigate whether Estrogen receptor-α participated in autophagy caused by tamoxifen, we constructed Estrogen receptor-α gene ESR/1 shRNA expression vector and it could effectively inhibit the expression of ER-α in MCF-7 cells. Our research shows that autophagy was decreased with the downregulation of ER-α, so we conclude that Estrogen receptor-a also involved in autophagy induced by tamoxifen in MCF-7 cells.

To find out the specifical role of autophagy in tamoxifen treated breast cancer cell MCF-7, we inhibited autophagy producing after tamoxifen treatment by pretreating the cells with chloroquine and 3-methyladenine, both commonly used as autophagy inhibitors. Another method for autophagy inhibition was Becline-1 siRNA transfection into MCF-7 cells. Than we stained MCF-7 cells with anti-Annexin V FITC and PI and examinated apoptotic rate by flow cytometer and we also detected activity of caspase7 in MCF-7 cells. The results indicate that inhibition of autophagy by the methods mentioned induced higher apoptotic level, therefore, autophagy protected MCF-7 from apoptosis and inhibiting autophagy may be a new strategy to augment the theraputic effect of tamoxifen treatment. In our study, we induced breast cancer cell MCF-7 resistant to TAM in vitro and we found much higher autophagic level in TAM resisitant cells compared with TAM not resisitant MCF-7 cells. We draw the conclusion that inhibition of autophagy induced by tamoxifen may be a new therapy for tamoxifen resisitant breast cancer.

Key words: tamoxifen, breast cancer, autophagy, MCF-7 cells, MAPKs, estrogen receptor, inhibition, apoptosis

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-17-08.