PAM4 rolling-shutter demodulation using a pixel-per-symbol labeling neural network for optical camera communications.

The typical optical camera communication (OCC) modulation scheme is based on binary intensity modulation. To increase the transmission data rate, multi-level modulation format is highly desirable. In this work, we bring forward and demonstrate a rolling shutter 4-level pulse amplitude modulation (PAM4) demodulation scheme for OCC systems using pixel-per-symbol labeling neural network (PPSL-NN) for the first time up to the authors' knowledge. A bit-rate distance product of 28.8 kbit/s • m per color is achieved. The proposed scheme is to calculate and re-sample the pixel-per-symbol (PPS) to make sure the same number of pixels in each PAM4 symbol is corresponding to a label for the neural network. Experiment results reveal that the proposed scheme can efficiently demodulate high speed PAM4 signal in the rolling shutter OCC pattern.

Employing DIALux to relieve machine-learning training data collection when designing indoor positioning systems.

We propose and demonstrate using the DIALux software with our proposed linear-regression machine-learning (LRML) algorithm for designing a practical indoor visible light positioning (VLP) system. Experimental results reveal that the average position errors and error distributions of the model trained via the DIALux simulation and trained via the experimental data match with each other. This implies that the training data can be generated in DIALux if the room dimensions and LED luminary parameters are available. The proposed scheme could relieve the burden of training data collection in VLP systems.

Rolling-shutter-effect camera-based visible light communication using RGB channel separation and an artificial neural network.

We propose and demonstrate a light-panel and rolling-shutter-effect (RSE) camera-based visible light communication (VLC) system using Z-score normalization, red/green/blue (RGB) color channel separation, and 1-D artificial neural network (ANN). The proposed scheme can mitigate the high inter-symbol interference (ISI) generated by the RSE pattern due to the low pixel-per-bit and high noise-ratio (NR) of the display contents.

CMOS camera based visible light communication (VLC) using grayscale value distribution and machine learning algorithm.

We demonstrate a visible light communication (VLC) system using light emitting diode (LED) backlight display panel and mobile-phone complementary-metal-oxide-semiconductor (CMOS) camera. The panel is primarily used for displaying advertisements. By modulating its backlight, dynamic contents (i.e. secondary information) can be transmitted wirelessly to users based on rolling shutter effect (RSE) of the CMOS camera. As different display content will be displayed on the panel, the VLC performance is significantly limited if the noise-ratio (NR) is too high. Here, we propose and demonstrate a CMOS RSE pattern demodulation scheme using grayscale value distribution (GVD) and machine learning algorithm (MLA) to significantly enhance the demodulation.

Real-time augmented fluoroscopy-guided lung marking for thoracoscopic resection of small pulmonary nodules.

BACKGROUND: Small pulmonary nodule localization via an endobronchial route is safe and has fewer complications than that with the transthoracic needle approach, but accurate marking without a navigation system remains challenging. We aimed to evaluate the safety and efficacy of endobronchial dye marking using conventional bronchoscopy guided by cone-beam computed tomography-derived augmented fluoroscopy (CBCT-AF) for small pulmonary nodules. METHODS: We retrospectively reviewed the clinical records of 61 nodules in 51 patients who underwent preoperative CBCT-AF-guided bronchoscopic dye marking, followed by thoracoscopic resection, between July 2018 and March 2019. RESULTS: The median nodule size was 8.6 mm [interquartile range (IQR) 7.0-11.8 mm], and the median distance from the pleural space was 15.4 mm (IQR 10.6-23.1 mm). All nodules were identifiable on CBCT images and annotated for AF. The median bronchoscopy duration was 8.0 min (IQR 6.0-11.0 min), and the median fluoroscopy duration was 2.2 min (IQR 1.2-4.0 min). The median radiation exposure (expressed as the dose area product) was 2337.2 µGym2 (IQR 1673.8-4468.8 µGym2). All nodules were successfully marked and resected, and the median duration from localization to surgery was 16.4 h (IQR 4.2-20.7 h). There were no localization-related complications or operative mortality, and the median length of the postoperative stay was 4 days (IQR 3-4 days). CONCLUSIONS: Bronchoscopic dye marking under CBCT-AF guidance before thoracoscopic surgery was safely conducted with satisfactory outcomes in our initial experience.

Localization of Small Pulmonary Nodules Using Augmented Fluoroscopic Bronchoscopy: Experience from 100 Consecutive Cases.

BACKGROUND: We developed augmented fluoroscopic bronchoscopy (AFB) for the localization of small pulmonary nodules. Here, we review the results of 100 consecutive cases of AFB localization performed in our institute in order to evaluate its efficacy, safety, and procedural details. METHODS: This study was a retrospective analysis of prospectively collected data. Between July 2018 and September 2019, a total of 100 patients with 124 small lung nodules underwent AFB localization with dye marking and/or microcoil placement. All localizations were performed in a cone-beam computed tomography examination room followed by thoracoscopic resection within 3 days. RESULTS: The mean nodule size was 9.7 mm, and the mean distance from the pleural space was 18.6 mm. Sixty-three patients received dye marking only, and 37 patients received microcoil placement with/without additional dye marking. The mean bronchoscopy duration was 10.4 min, and the mean fluoroscopy duration was 3.4 min. The mean radiation exposure (expressed as the dose-area product) was 3140.8 µGy × m2. The AFB procedures were successful in 94 patients [augmented fluoroscopy discrepancy (n = 2), incomplete C-arm confirmation (n = 3), microcoil unlooping (n = 1)]; of those, 91 received successful marker-guided resection [invisible dye (n = 2), failed nodule resection with first wedge (n = 1)]. The mean length of postoperative stay and chest drainage was 4.2 and 2.9 days, respectively. CONCLUSIONS: The AFB technique is a safe and reproducible alternative for localizing small pulmonary nodules, and various localization strategies can be implemented for different nodule locations and resection plans.

Using logistic regression classification for mitigating high noise-ratio advisement light-panel in rolling-shutter based visible light communications.

We propose and experimentally demonstrated a light-panel and image sensor based visible light communication (VLC) system using machine learning (ML) algorithm. The ML algorithm is compared with the traditional demodulation scheme and the experimental results show that even at very high noise-ratio (NR) light-panel display content, the proposed ML algorithm shows significant bit error rate (BER) improvement.

Cumulative experience of preoperative real-time augmented fluoroscopy-guided endobronchial dye marking for small pulmonary nodules: An analysis of 30 initial patients.

BACKGROUND/PURPOSE: Cone-beam computed tomography-derived augmented fluoroscopy (CBCT-AF) for use in guiding endobronchial dye marking of small pulmonary nodules prior to thoracoscopic surgery is still under development. We sought to evaluate the effect of the cumulative experience on procedural parameters of CBCT-AF-guided endobronchial dye marking for preoperative localization of small pulmonary nodules. METHODS: Clinical variables and treatment outcomes of the 30 initial patients with small pulmonary nodules who were managed with CBCT-AF-guided endobronchial dye marking followed by thoracoscopic resection in our institution were analyzed. Two sequential groups of patients (group I and group II, n = 15 each) were compared with regard to localization time and radiation doses. The Mann-Whitney U test and chi-square test or Fisher exact test were used in the statistical analyses. RESULTS: In the entire cohort, the median size of solitary pulmonary nodules on preoperative computed tomography (CT) images was 9.3 mm (interquartile range, 7.4-13.6 mm), and their median distance from the pleural surface was 15.2 mm (interquartile range, 10.3-27.1 mm). The median tumor depth-to-size ratio was 1.6 (interquartile range, 1.1-2.3). A significant reduction in single DynaCT radiation (3690.4 versus [vs.] 1132.3 µGym2; P < 0.001) and total radiation exposure (median, 4878.8 vs. 1673.8 µGym2; P < 0.001) was noted in group II (late patients) compared with group I. CONCLUSION: Our initial results of CBCT-AF-guided lung marking demonstrate that the cumulative experience with several technical modifications can achieve the same purpose of endobronchial localization with less procedure-related radiation exposure.

Mitigation of performance degradation due to dynamic display contents in visible light communication using TV backlight and CMOS image sensor.

Here, we propose and demonstrate a performance degradation mitigation scheme in TV backlight and smart-phone-based visible light communication (VLC) system when the display content in the light-panel is dynamically changing. In order to evaluate the influence of the dynamic display contents to the VLC performance, we use a noise-ratio (NR) and noise-ratio standard deviation (NRSD) as the figure-of-merits for the bright-and-dark contrast of the display content; and the dispersal of the changing display content regarding the bright-and-dark contrast respectively. Performances of 4 dynamic display contents with different combinations of NR and NRSD are analyzed. They are: low NR and low NRSD (NR = 36.69%; NRSD = 0.0226); low NR and high NRSD (NR = 30.09%; NRSD = 0.2698); high NR and low NRSD (NR = 81.66%; NRSD = 0.0052); high NR and high NRSD (NR = 73.91%; and NRSD = 0.2717). The proposed scheme can work well; that is, even the transmission distance is up to 200 cm in both smart-phones. If the proposed scheme is not used, then high success rate can be observed only at the low NR and low NRSD display content when the transmission distance is < 100 cm.

Using advertisement light-panel and CMOS image sensor with frequency-shift-keying for visible light communication.

A frequency-shift-keying (FSK) visible light communication (VLC) system is proposed and demonstrated using advertisement light-panel as transmitter and mobile-phone image sensor as receiver. The developed application program (APP) in mobile-phone can retrieve the rolling shutter effect (RSE) pattern produced by the FSK VLC signal effectively. Here, we also define noise-ratio value (NRV) to evaluate the contrast of different advertisements displayed on the light-panel. Both mobile-phones under test can achieve success rate > 96% even when the transmission distance is up to 200 cm and the NRVs are low.

α-Galactosylceramide but not phenyl-glycolipids induced NKT cell anergy and IL-33-mediated myeloid-derived suppressor cell accumulation via upregulation of egr2/3.

Strategies for cancer immunotherapy include activating immune system for therapeutic benefit or blockade of immune checkpoints. To harness innate immunity to fight cancer, α-galactosylceramide (α-GalCer) has been used to activate NKT cells. Unfortunately, administration of α-GalCer causes long-term NKT cell anergy, but the molecular mechanism is unclear. In this study, we showed that α-GalCer-triggered egr2/3, which induced programmed death 1 and cbl-b in NKT cells, leading to NKT cell anergy. We also uncovered the induction of the immunosuppressive myeloid-derived suppressor cells (MDSCs) in the spleen by α-GalCer that might attenuate its antitumor efficacy. The accumulation of MDSC was accompanied by 20-fold rise in their arg-1 mRNAs and enhanced expression of programmed death 1/programmed death ligand 1. Furthermore, α-GalCer-induced egr-2/3 in hepatic NKT cells upregulated their TRAIL in addition to Fas ligand (FasL) and induced alarm signaling molecule IL-33 in Kupffer cells, presumably because of liver damage triggered by TRAIL/FasL. We further demonstrated that IL-33-stimulated macrophages produce G-CSF, which in turn, boosted MDSCs. Thus, α-GalCer-induced FasL/TRAIL and IL-33 provided a novel mechanism underlying α-GalCer-induced hepatotoxicity and MDSC accumulation. In contrast, analogs of α-GalCer containing phenyl group in the lipid tail could neither induce NKT anergy nor enhance MDSCs accumulation. Furthermore, tumor-infiltrating MDSCs in mice injected repeatedly with α-GalCer were 2-fold higher than those treated with phenyl-glycolipids. These results not only revealed the induction of MDSC via IL-33 as a new mechanism for α-GalCer-elicited immunosuppression but also provided one of the mechanisms underlying the superior antitumor potency of phenyl-glycolipids. Our findings have important implications for the development of NKT-stimulatory glycolipids as vaccine adjuvants and anticancer therapeutics.

Immunogenicity study of Globo H analogues with modification at the reducing or nonreducing end of the tumor antigen.

Globo H-based therapeutic cancer vaccines have been tested in clinical trials for the treatment of late stage breast, ovarian, and prostate cancers. In this study, we explored Globo H analogue antigens with an attempt to enhance the antigenic properties in vaccine design. The Globo H analogues with modification at the reducing or nonreducing end were synthesized using chemoenzymatic methods, and these modified Globo H antigens were then conjugated with the carrier protein diphtheria toxoid cross-reactive material (CRM) 197 (DT), and combined with a glycolipid C34 as an adjuvant designed to induce a class switch to form the vaccine candidates. After Balb/c mice injection, the immune response was studied by a glycan array and the results showed that modification at the C-6 position of reducing end glucose of Globo H with the fluoro, azido, or phenyl group elicited IgG antibody response to specifically recognize Globo H (GH) and the GH-related epitopes, stage-specific embryonic antigen 3 (SSEA3) (also called Gb5) and stage-specific embryonic antigen 4 (SSEA4). However, only the modification of Globo H with the azido group at the C-6 position of the nonreducing end fucose could elicit a strong IgG immune response. Moreover, the antibodies induced by these vaccines were shown to recognize GH expressing tumor cells (MCF-7) and mediate the complement-dependent cell cytotoxicity against tumor cells. Our data suggest a new potential approach to cancer vaccine development.

Avidity of CD1d-ligand-receptor ternary complex contributes to T-helper 1 (Th1) polarization and anticancer efficacy.

Invariant natural killer T cell (NKT) cells (iNKT cells) produce both T-helper 1 (Th1) and T-helper 2 cytokines in response to α-Galactosylceramide (α-GalCer) stimulation and are thought to be the important effectors in the regulation of both innate and adaptive immunity involved in autoimmune disorders, microbial infections, and cancers. However, the anticancer effects of α-GalCer were limited in early clinical trial. In this study, several analogs of α-GalCer, containing phenyl groups in the lipid tails were found to stimulate murine and human iNKT cells to secrete Th1-skewed cytokines and exhibit greater anticancer efficacy in mice than α-GalCer. We explored the possibility of different Vß usages of murine Vα14 iNKT or human Vα24 iNKT cells, accounting for differential cytokine responses. However, T-cell receptor Vß analysis revealed no significant differences in Vß usages by α-GalCer and these phenyl glycolipid analogs. On the other hand, these phenyl glycolipids showed greater binding avidity and stability for iNKT T-cell receptor when complexed with CD1d. These findings suggest that CD1d-phenyl glycolipid complexes may interact with the same population of iNKT cells but with higher avidity and stability to drive Th1 polarization. Thus, this study provides a key to the rational design of Th1 biased CD1d reactive glycolipids in the future.

An Adjuvanted Vaccine-Induced Pathogenesis Following Influenza Virus Infection.

An incomplete Freund's adjuvant elicited an overt pathogenesis in vaccinated mice following the intranasal challenge of A/California/07/2009 (H1N1) virus despite the induction of a higher specific antibody titer than other adjuvanted formulations. Aluminum hydroxide adjuvants have not induced any pathogenic signs in a variety of formulations with glycolipids. A glycolipid, α-galactosyl ceramide, improved a stimulatory effect of distinct adjuvanted formulations on an anti-influenza A antibody response. In contrast to α-galactosyl ceramide, its synthetic analogue C34 was antagonistic toward a stimulatory effect of an aluminum hydroxide adjuvant on a specific antibody response. The aluminum hydroxide adjuvant alone could confer complete vaccine-induced protection against mortality as well as morbidity caused by a lethal challenge of the same strain of an influenza A virus. The research results indicated that adjuvants could reshape immune responses either to improve vaccine-induced immunity or to provoke an unexpected pathogenic consequence. On the basis of these observations, this research connotes the prominence to develop a precision adjuvant for innocuous vaccination aimed at generating a protective immunity without aberrant responses.

In vivo protection provided by a synthetic new alpha-galactosyl ceramide analog against bacterial and viral infections in murine models.

Alpha-galactosyl ceramide (α-GalCer) has been known to bind to the CD1d receptor on dendritic cells and activate invariant natural killer T (iNKT) cells, which subsequently secrete T-helper-cell 1 (Th1) and Th2 cytokines, which correlate with anti-infection activity and the prevention of autoimmune diseases, respectively. α-GalCer elicits the secretion of these two cytokines nonselectively, and thus, its effectiveness is limited by the opposing effects of the Th1 and Th2 cytokines. Reported here is the synthesis of a new α-GalCer analog (compound C34), based on the structure of CD1d, with a 4-(4-fluorophenoxy) phenyl undecanoyl modification of the N-acyl moiety of α-GalCer. Using several murine bacterial and viral infection models, we demonstrated that C34 has superior antibacterial and antiviral activities in comparison with those of several other Th1-selective glycolipids and that it is most effective by administering it to mice in a prophylactic manner before or shortly after infection.

Single-stage hybrid localization: a combination of bronchoscopic lung mapping followed by post-mapping computed tomographic reconstruction and additional transthoracic needle localization in a cone beam computed tomography room.

BACKGROUND: Bronchoscopic lung mapping is a multispot dye-marking technique, which should be performed under real-time fluoroscopic guidance and post-mapping computed tomographic reconstruction. This study aimed to investigate the feasibility of lung mapping followed by post-mapping computed tomography (CT) and additional needle localization in a cone bean CT (CBCT) room. METHODS: Between February 1, 2018 and August 31, 2018, 11 consecutive patients presenting with 14 lung lesions underwent bronchoscopic lung mapping in a CBCT room followed by thoracoscopic surgery. The efficacy and safety of the procedure were assessed through a retrospective chart review. RESULTS: The median size of the pulmonary lesions was 8.1 mm [interquartile range (IQR), 7.2-10.8 mm] with a median depth-to-size ratio (D-S) ratio of 2.43 (IQR, 1.56-2.79). Additional needle localizations were performed in 4 patients, of which 3 and 1 patients underwent dual localization with dye and microcoil and localization with dye only, respectively. The median total localization time was 28 min (IQR, 18-69 min), and the median radiation exposure was 345.0 mGy (IQR, 161.8-486.6 mGy). A total of 8 wedge resections, 5 segmentectomies, and 1 lobectomy were performed. The final pathological diagnoses were as follows: primary lung cancer (n=6), lung metastases (n=4), and benign lung lesions (n=4). No adverse events were observed, and the median length of postoperative stay was 4 days (IQR, 3-5 days). CONCLUSIONS: Bronchoscopic lung mapping followed by post-mapping CT and additional needle localization can be performed together in a single examination room equipped with a C-arm CBCT, and the results of localization are contributory to the surgery.

Phenyl Glycolipids with Different Glycosyl Groups Exhibit Marked Differences in Murine and Human iNKT Cell Activation.

Glycosphingolipids (GSLs) bearing the α-galactosyl headgroup and the acyl chain terminated with a phenyl derivative were found to be more potent than α-galactosyl ceramide (αGalCer) to stimulate both murine and human invariant natural killer T (iNKT) cells and to induce an antibody isotope switch to IgG. In this study, we replaced the galactosyl group with glucose (αGlc) and its fluoro-analogs and found that phenyl GSLs with αGlc (C34-Glc) and its fluoro-analog 6F-C34-Glc were stronger than those with αGal in stimulating human iNKT cells but weaker in mice. Their activities have a strong correlation with the binding avidities of the ternary interaction between the iNKT-cell receptor (iNKTCR) and CD1d-GSL complex. It was the iNKTCR rather than CD1d that dictated the species-specific responses. C34-Glc was further used as an adjuvant for a SSEA4-crm-197 vaccine, and after immunization in mice, the vaccine was highly effective against Lewis lung carcinoma.

Potent adjuvant effects of novel NKT stimulatory glycolipids on hemagglutinin based DNA vaccine for H5N1 influenza virus.

H5N1 influenza virus is a highly pathogenic virus, posing a pandemic threat. Previously, we showed that phenyl analogs of α-galactosylceramide (α-GalCer) displayed greater NKT stimulation than α-GalCer. Here, we examined the adjuvant effects of one of the most potent analogs, C34, on consensus hemagglutinin based DNA vaccine (pCHA5) for H5N1 virus. Upon intramuscular electroporation of mice with pCHA5 with/without various α-GalCer analogs, C34-adjuvanted group developed the highest titer against consensus H5 and more HA-specific IFN-γ secreting CD8 cells (203±13.5) than pCHA5 alone (152.6±13.7, p<0.05). Upon lethal challenge of NIBRG-14 virus, C34-adjuvanted group (84.6%) displayed higher survival rate than pCHA5 only group (46.1%). In the presence of C34 as adjuvant, the antisera displayed broader and greater neutralizing activities against virions pseudotyped with HA of clade 1, and 2.2 than pCHA5 only group. Moreover, to simulate an emergency response to a sudden H5N1 outbreak, we injected mice intramuscularly with single dose of a new consensus H5 (pCHA5-II) based on 1192 full-length H5 sequences, with C34 as adjuvant. The latter not only enhanced the humoral immune response and protection against virus challenge, but also broadened the spectrum of neutralization against pseudotyped HA viruses. Our vaccine strategy can be easily implemented for any H5N1 virus outbreak by single IM injection of a consensus H5 DNA vaccine based on updated HA sequences using C34 as an adjuvant.