Synthesis and evaluation of 18F-labeled procainamide as a PET imaging agent for malignant melanoma.

Malignant melanoma has an aggressive nature and a high metastatic propensity resulting in the highest mortality rate of any skin cancer. In this study, we synthesized 18F-labeled procainamide (PCA) for detection of melanoma using positron emission tomography (PET), and evaluated its biological characteristics. The non-decay-corrected radiochemical yield of 18F-PCA was 10-15% and its in vitro stability was over 98% for 2 h. At 1 h, cellular uptake of 18F-PCA was 3.8-fold higher in a group with the presence of l-tyrosine than in a non-l-tyrosine-treated group. Furthermore, 18F-PCA permitted visualization of B16F10 (mouse melanoma) xenografts on microPET after intravenous injection, and was retained in the tumor for 60 min, with a high tumor-to-liver uptake ratio. 18F-PCA showed specific melanoma uptake in primary lesions with a high melanin targeting ability in small animal models. 18F-PCA may have potential as a PET imaging agent for direct melanoma detection.

Ultrasensitive detection of malignant melanoma using PET molecular imaging probes.

Malignant melanoma has one of the highest mortality rates of any cancer because of its aggressive nature and high metastatic potential. Clinical staging of the disease at the time of diagnosis is very important for the prognosis and outcome of melanoma treatment. In this study, we designed and synthesized the 18F-labeled pyridine-based benzamide derivatives N-(2-(dimethylamino)ethyl)-5-[18F]fluoropicolinamide ([18F]DMPY2) and N-(2-(dimethylamino)ethyl)-6-[18F]fluoronicotinamide ([18F]DMPY3) to detect primary and metastatic melanoma at an early stage and evaluated their performance in this task. [18F]DMPY2 and [18F]DMPY3 were synthesized by direct radiofluorination of the bromo precursor, and radiochemical yields were ∼15-20%. Cell uptakes of [18F]DMPY2 and [18F]DMPY3 were >103-fold and 18-fold higher, respectively, in B16F10 (mouse melanoma) cells than in negative control cells. Biodistribution studies revealed strong tumor uptake and retention of [18F]DMPY2 (24.8% injected dose per gram of tissue [ID/g] at 60 min) and [18F]DMPY3 (11.7%ID/g at 60 min) in B16F10 xenografts. MicroPET imaging of both agents demonstrated strong tumoral uptake/retention and rapid washout, resulting in excellent tumor-to-background contrast in B16F10 xenografts. In particular, [18F]DMPY2 clearly visualized almost all metastatic lesions in lung and lymph nodes, with excellent image quality. [18F]DMPY2 demonstrated a significantly higher tumor-to-liver ratio than [18F]fluorodeoxyglucose ([18F]FDG) and the previously reported benzamide tracers N-[2-(diethylamino)-ethyl]-5-[18F]fluoropicolinamide ([18F]P3BZA) and N-[2-(diethylamino)-ethyl]-4-[18F]fluorobenzamide ([18F]FBZA) in B16F10-bearing or SK-MEL-3 (human melanoma)-bearing mice. In conclusion, [18F]DMPY2 might have strong potential for the diagnosis of early stage primary and metastatic melanoma using positron emission tomography (PET).

Effects of air blower and pump failures on the performance of A2O processes for wastewater treatment.

The unexpected failure of equipment such as pumps and fans in wastewater treatment plants can reduce wastewater treatment efficiency, leading to direct leakage of untreated wastewater into the environment. It is hence important to predict the possible consequences of equipment failure to minimize the leakage of harmful substances. This study examines the impacts of equipment shutdown on the performance and recovery time of a laboratory-scale anaerobic/anoxic/aerobic system with regard to reactor conditions and water quality. Two days after the air blowers are stopped, the concentrations of the soluble chemical oxygen demand, NH4-N, and PO4-P in the effluent of the settling tank increase to 122 mg/L, 23.8 mg/L, and 46.6 mg/L, respectively. These concentrations return to their initial values after 12, 24, and 48 h of restarting the air blowers. The concentrations of PO4-P and NO3-N in the effluent increase to 58 mg/L and 20 mg/L, respectively, about 24 h after stopping the return activated sludge and mixed liquor recirculation pumps, owing to the release of phosphates in the settling tank and inhibition of denitrification.

Accelerating a spatially varying aberration correction of holographic displays with low-rank approximation.

Correction of spatially varying aberrations in holographic displays often requires intractable computational loads. In this Letter, we introduce a low-rank approximation method that decomposes sub-holograms into a small number of modes, thereby reformulating the computer-generated hologram calculation into a summation of a few convolutions. The low-rank approximation is carried out with two different algorithms: the Karhunen-Loeve transform as the optimum solution with respect to the mean-squared error criterion and a novel, to the best of our knowledge, optimization method to provide uniform image quality over the entire field of view. The proposed method is two orders of magnitude faster than the conventional point-wise integration method in our experimental setup, with comparable image quality.

Off-axis camera-in-the-loop optimization with noise reduction strategy for high-quality hologram generation.

In this Letter, we introduce a noise reduction (NR) strategy in the off-axis camera-in-the-loop (CITL) optimization for high-quality hologram generation. Our proposal adopts the Gaussian blur in the NR strategy to suppress the high-frequency noise and improve the optimization convergence. A double-hologram generation technique is used to reduce the noise further. The off-axis system's aberrations are eliminated by integrating the aberration compensation method as well. Compared with the original CITL method, the image quality of the proposed method is improved by approximately 5.5 dB in the optical experiment.

In situ x-ray-induced acoustic computed tomography with a contrast agent: a proof of concept.

X-ray-induced acoustic computed tomography (XACT) has shown great potential as a hybrid imaging modality for real-time non-invasive x-ray dosimetry and low-dose three-dimensional (3D) imaging. While promising, one drawback of the XACT system is the underlying low signal-to-noise ratio (SNR), limiting its in vivo clinical use. In this Letter, we propose the first use of a conventional x-ray computed tomography contrast agent, Gastrografin, for improving the SNR of in situ XACT imaging. We obtained 3D volumetric XACT images of a mouse's stomach with orally injected Gastrografin establishing the proposal's feasibility. Thus, we believe, in the future, our proposed technique will allow in vivo imaging and expand or complement conventional x-ray modalities, such as radiotherapy and accelerators.

GPS Spoofing Detection Method for Small UAVs Using 1D Convolution Neural Network.

The navigation of small unmanned aerial vehicles (UAVs), such as quadcopters, significantly relies on the global positioning system (GPS); however, UAVs are vulnerable to GPS spoofing attacks. GPS spoofing is an attempt to manipulate a GPS receiver by broadcasting manipulated signals. A commercial GPS simulator can cause a GPS-guided drone to deviate from its intended course by transmitting counterfeit GPS signals. Therefore, an anti-spoofing technique is essential to ensure the operational safety of UAVs. Various methods have been introduced to detect GPS spoofing; however, most methods require additional hardware. This may not be appropriate for small UAVs with limited capacity. This study proposes a deep learning-based anti-spoofing method equipped with 1D convolutional neural network. The proposed method is lightweight and power-efficient, enabling real-time detection on mobile platforms. Furthermore, the performance of our approach can be enhanced by increasing training data and adjusting the network architecture. We evaluated our algorithm on the embedded board of a drone in terms of power consumption and inference time. Compared to the support vector machine, the proposed method showed better performance in terms of precision, recall, and F-1 score. Flight test demonstrated our algorithm could successfully detect GPS spoofing attacks.

Protein arginine methyltransferase 1 contributes to the development of allergic rhinitis by promoting the production of epithelial-derived cytokines.

BACKGROUND: Arginine methylation is a posttranslational modification mediated by protein arginine methyltransferases (PRMTs). Although previous studies have shown that PRMT1 contributes to the severity of allergic airway inflammation or asthma, the underlying mechanism is poorly understood. OBJECTIVE: This study aimed to explore the role of PRMT1 and its relevant mechanism in the development of allergic rhinitis (AR). METHODS: The expression levels of PRMTs and cytokines were determined by RT-PCR, and the localization of PRMT1 was determined by immunohistochemistry and confocal microscopy. The levels of house dust mite (HDM)-specific immunoglobulins in serum and of cytokines in nasal lavage fluids were determined by ELISA. PRMT1 inhibition was achieved by siRNA and treatment with the pan PRMT inhibitor arginine N-methyltransferase inhibitor-1. RESULTS: PRMT1 expression was significantly increased in the nasal mucosa of patients and mice with AR. The degree of eosinophilic infiltration in the nasal mucosa was reduced in PRMT1+/- AR mice compared with wild-type mice. PRMT1 haploinsufficiency reduced the levels of HDM-specific immunoglobulins in serum and those of TH2 (IL-4, IL-5, and IL-13) and epithelial (thymic stromal lymphopoietin [TSLP], IL-25, and IL-33) cytokines in the nasal lavage fluids of AR mice. In nasal epithelial cells, HDM and IL-4 cooperate to enhance PRMT1 expression through a mitogen-activated protein kinase-dependent pathway. In addition, PRMT1 was essential for the production of TSLP, IL-25, and IL-33 in response to HDM and IL-4. Arginine N-methyltransferase inhibitor-1 treatment alleviated AR in the mouse model. CONCLUSIONS: PRMT1 plays an important role in AR development by regulating epithelial-derived cytokine production and might be a new therapeutic target for AR.

cPlot: Contig-Plotting Visualization for the Analysis of Short-Read Nucleotide Sequence Alignments.

Advances in the next-generation sequencing technology have led to a dramatic decrease in read-generation cost and an increase in read output. Reconstruction of short DNA sequence reads generated by next-generation sequencing requires a read alignment method that reconstructs a reference genome. In addition, it is essential to analyze the results of read alignments for a biologically meaningful inference. However, read alignment from vast amounts of genomic data from various organisms is challenging in that it involves repeated automatic and manual analysis steps. We, here, devised cPlot software for read alignment of nucleotide sequences, with automated read alignment and position analysis, which allows visual assessment of the analysis results by the user. cPlot compares sequence similarity of reads by performing multiple read alignments, with FASTA format files as the input. This application provides a web-based interface for the user for facile implementation, without the need for a dedicated computing environment. cPlot identifies the location and order of the sequencing reads by comparing the sequence to a genetically close reference sequence in a way that is effective for visualizing the assembly of short reads generated by NGS and rapid gene map construction.

Evaluation of fits of metal copings fabricated by using selective laser melting at various angles.

STATEMENT OF PROBLEM: Information on the fabrication of metal by selective laser melting (SLM) systems positioned at different angles is sparse. PURPOSE: The purpose of this in vitro study was to evaluate the extent of marginal and internal gaps in metal copings fabricated at different angles by using an SLM fabrication system. MATERIAL AND METHODS: A master metal model was produced and replicated (N=10) with silicone impressions and dental stone. Standard tessellation language (STL) files of the 10 coping designs were then obtained by using a model scanner and a 3D design software program on a scannable working die. Co-Cr alloy metal copings were fabricated by the SLM fabrication system at 45, 90, and 180 degrees. The marginal and internal gaps were measured by the silicone replica technique. The measured data were analyzed by using the nonparametric Kruskal-Wallis H test (α=.05). RESULTS: The specimens fabricated at 180 degrees showed the best fit in terms of the marginal gap, while the worst fit was observed in the specimens fabricated at 90 degrees. Statistically significant differences were seen among the marginal gaps produced in the 3 groups (P<.001). In terms of internal fit, the axial wall gap showed the best fit, and the occlusal gap the worst. The best fit overall was 66 µm at the axial wall of the 180-degree group, and the worst in the 90-degree group, at 663 µm. Statistically significant differences were observed between the chamfers, axial walls, and the occlusal gaps of the 3 groups (P<.001). CONCLUSIONS: Restorations fabricated by using an SLM system at 180 degrees were clinically acceptable. However, more research is required to investigate the performance of metal copings produced at 45 and 90 degrees to evaluate their clinical acceptability.

Effect of layer thickness setting on the adaptation of stereolithography apparatus-fabricated metal frameworks for removable partial dentures: An in vitro study.

STATEMENT OF PROBLEM: A staircase effect is noted in the fabrication of metal frameworks for removable partial dentures (RPDs) when using stereolithography apparatus (SLA). It affects the adaptation of the definitive metal framework depending on the layer thickness setting. However, studies on the effect of the layer thickness setting on the adaptation of metal frameworks are lacking. PURPOSE: The purpose of this in vitro study was to determine the optimal layer thickness through comparative analysis of the adaptation of SLA-fabricated metal frameworks with different layer thickness settings. MATERIAL AND METHODS: A total of 15 metal RPD frameworks were SLA-fabricated by using 3 different layer thickness settings (16 µm, 50 µm, and 100 µm). The adaptation of the frameworks was measured by using the silicone replica technique, sectioned at the canine, first molar, and second molar regions by using a guide. The thickness of the light-body silicone was measured with a digital microscope at 3 points in each of the 3 areas. The measurements of the adaptation were statistically analyzed using the nonparametric Kruskal-Wallis test and post hoc Mann-Whitney U test with Bonferroni correction. RESULTS: The gaps measured in each area showed statistically significant differences in all 3 groups (P<.05). In the anterior, middle, and posterior areas, the 16-µm metal framework group showed the narrowest gaps (207 ±46 µm, 195 ±49 µm, and 188 ±40 µm, respectively). The 3 groups showed statistically significant differences in total gaps in the RPD frameworks relative to the layer thickness settings (P<.05); the total gap was lowest (197 ±42 µm) for the 16-µm group. CONCLUSIONS: For SLA, 50 µm is the recommended layer thickness considering the effect of layer thickness settings on the adaptation of the RPD framework and the fabrication time.

Distortion corrected tomographic near-eye displays using light field optimization.

Several multifocal displays have been proposed to provide accurate accommodation cues. However, multifocal displays have an undesirable feature, which is especially emphasized in near-eye displays configuration, that the field of views (FOVs) of the virtual planes change over depth. We demonstrate that this change in FOV causes image distortions, which reduces overall image quality, and depth perception error due to the variation of image sizes according to depths. Here, we introduce a light field optimization technique to compensate for magnification variations among the focal planes. Our approach alleviates image distortions, especially noticeable in the contents with large depth discontinuity, and reconstructs the image size to precise depths, while maintaining a specific tolerance length for the target eye relief. To verify the feasibility of the algorithm, we employ this optimization method for the tomographic near-eye display system to acquire the optimal image and backlight sequences for a volumetric scene. In general, we confirm that the structural similarity index measure of reconstructed images against ground truth increases by 20% when the eye relief is 15 mm, and the accommodation cue is appropriately stimulated at the target depth with our proposed method.

3D printing-based mirrored image component for seamless modular curved-edge displays.

A facile method for designing and fabricating a concave mirror from a 3D printed mold is proposed for a seamless modular curved-edge display. The concave mirror is placed on the seam of modular curved-edge display, thereby reflecting images at the curved-edge area toward the observer direction. By investigating the concave mirror structures based on parametric modeling, we obtain a continuous image in a modular curved-edge display by optically concealing the seam. We also analyze the luminance distribution and the viewing angle of the seamless modular curved-edge display to show the capability of concealing the seam by the concave mirror.

Bisoprolol-based 18F-PET tracer: Synthesis and preliminary in vivo validation of ß1-blocker selectivity for ß1-adrenergic receptors in the heart.

The selectivity of a drug toward various isoforms of the target protein family is important in terms of toxicology. Typically, drug or candidate selectivity is assessed by in vitro assays, but in vivo investigations are currently lacking. Positron emission tomography (PET) allows the non-invasive determination of the in vivo distribution of a radiolabeled drug, which can provide in vivo data regarding drug selectivity. Since the discovery of propranolol, a non-selective ß-blocker inhibiting both ß1- and ß2-adrenoreceptors (ß-ARs), various selective ß1-blockers, including bisoprolol, have been developed to overcome disadvantages associated with ß2-AR inhibition. As a proof of concept, we performed an in vivo PET study to understand the selectivity and efficacy of bisoprolol as a selective ß-blocker toward ß1-AR, as the heart and peripheral smooth muscles demonstrate distinct populations of ß1- and ß2-ARs. Biodistribution of 18F-labeled bisoprolol (1, [18F]bisoprolol) showed the retention of its uptake in the heart compared with other ß-AR-rich organs at late time points post-injection. The competitive blocking assay using unlabeled bisoprolol exhibited no inhibition of [18F]bisoprolol uptake in any organ but exhibited significantly rapid loss of radioactivity between two different time points in ß1-AR-rich organs such as the heart and brain. Furthermore, the organ-to-blood ratio revealed the slow excretion and better accumulation of [18F]bisoprolol inside the heart. Collectively, the ex vivo biodistribution and blocking study presented insightful evidence to better comprehend the in vivo distribution pattern of bisoprolol as a selective inhibitor targeting ß1-ARs in the heart and provided the possibility of PET as an in vivo technique for evaluating drug selectivity.

Treatment of Radial Longitudinal Deficiency: An International Survey.

PURPOSE: The treatment of radial longitudinal deficiency (RLD) is highly variable without clear guidelines in the literature. The current study investigated variability among hand surgeons in treatment approaches for RLD patients with anomalies of the thumb and forearm. METHODS: An online survey was distributed to 105 self-identified North American pediatric hand surgeons and 23 international pediatric hand surgeons. The survey was developed after consideration of the controversies in RLD treatment. Variations in diagnostic approach, timing of treatment, surgical indications, and surgical techniques were presented in a 21-question survey. RESULTS: Seventy-four (57.8%) surgeons completed the survey. For type 2 hypoplastic thumb reconstruction, 81% of surgeons prefer the flexor digitorum superficialis transfer with others using the abductor digiti minimi transfer. Ninety-four percent and 100% of surgeons favored pollicization for type 3B and type 4 hypoplastic thumb, respectively. When performing pollicization, 88% of surgeons strive for tip-to-tip pinch, with 50% preferring 100° rotation and 38% greater than 120°, compared with 12% who preferred tip-to-side pinch. Nearly half of surgeons stated they would not recommend pollicization for a patient with a stiff index finger who utilizes ulnar prehension. Ninety percent of surgeons preferred observation for a type 1 radius. Type 2 treatment preferences were highly variable, the most common response being radius lengthening. For type 3/4 radius deficiency, surgeons were divided between soft tissue release with bilobed flap and centralization (42% and 36%, respectively). If radial deviation could not be passively corrected, 63% preferred an external fixator for soft tissue distraction before centralizing. Ulnar prehension functional pattern changed treatment for 45% of surgeons in type 3/4 radius. CONCLUSIONS: This study provides information on areas of agreement and disagreement in the treatment of RLD. Specifically, there was consensus for treatment of types 3B and 4 thumbs and type 1 radius. Consensus was lacking for the amount of rotation in positioning of the pollicized digit, the role of pollicization with the stiff index finger, and also in the treatment of types 2, 3, or 4 radius. CLINICAL RELEVANCE: This study provides a framework to establish treatment guidelines for thumb hypoplasia and RLD and has identified areas lacking consensus and that require additional study.

Congenital Upper-Extremity Differences: A Thematic Analysis of On-Line Discussion Boards.

PURPOSE: On-line discussion boards (DBs) are used by patients and family members to pose questions and share experiences with a broader community. Systematic analysis of the text posted to DBs about congenital upper-extremity (UE) differences may allow physicians to identify and address patients' questions and concerns better. METHODS: We used Google and Yahoo! Internet search engines to identify on-line DBs pertaining to congenital UE differences. Posts written between January 1, 2009 and January 1, 2019 were collected and analyzed. Each on-line post was coded by 2 researchers using 3 rounds of grounded theory: open coding, axial coding, and selective coding. This allowed comprehensive, central themes of the DBs to emerge. RESULTS: We collected 521 posts and analyzed 420 posts from 152 threads. A total of 163 unique users contributed to posts. Parents of a child with a congenital UE difference accounted for the majority of users (65%), most of which were postnatal (91%). Of posts written by patients, 48% expressed negative emotions pertaining to their difference, whereas 17% conveyed a positive experience. Five selective codes were identified from posts written by non-administrators: (1) Connecting With Others, (2) Emotional Aspects, (3) Treatment, (4) Diagnosis, and (5) Function. Connecting With Others was the most frequently assigned selective code; users were looking to establish a connection in 73% of posts. Posts seeking information (n = 106) were more often technical in nature than were posts providing information (54% vs 44%). Posts providing information (n = 206) were more often emotional (18% vs 13%). CONCLUSIONS: Individuals accessing on-line DBs are commonly searching for technical and emotional support from others. Through analysis and identification of the themes from these posts, we believe physicians should be proactive in addressing technical concerns through education and counseling, but should also validate emotional concerns and assist families and patients via support groups or connections to others. CLINICAL RELEVANCE: Treating surgeons can improve their care of patients with congenital UE differences by better understanding the needs of patients and their families that may not be elucidated in a traditional patient encounter.

Dietary Collagen Hydrolysates Ameliorate Furrowed and Parched Skin Caused by Photoaging in Hairless Mice.

Collagen hydrolysates have been suggested as a favorable antiaging modality in skin photoaged by persistent exposure to ultraviolet radiation (UV). The current study evaluated the beneficial effect of collagen hydrolysates (fsCH) extracted from Pangasius hypophthalmus fish skin on wrinkle formation and moisture preservation in dorsal skin of hairless mice challenged with UV-B. Inter-comparative experiments were conducted for anti-photoaging among fsCH, retinoic acid (RA), N-acetyl-D-glucosamine (NAG), and glycine-proline-hydroxyproline (GPH). Treating human HaCaT keratinocytes with 100-200 µg/mL fsCH reciprocally ameliorated the expression of aquaporin 3 (AQP3) and CD44 deranged by UV-B. The UV-B-induced deep furrows and skin thickening were improved in parched dorsal skin of mice supplemented with 206-412 mg/kg fsCH as well as RA and GPH. The UV-B irradiation enhanced collagen fiber loss in the dorsal dermis, which was attenuated by fsCH through enhancing procollagen conversion to collagen. The matrix metalloproteinase expression by UV-B in dorsal skin was diminished by fsCH, similar to RA and GPH, via blockade of collagen degradation. Supplementing fsCH to UV-B-irradiated mice decreased transepidermal water loss in dorsal skin with reduced AQP3 level and restored keratinocyte expression of filaggrin. The expression of hyaluronic acid synthase 2 and hyaluronidase 1 by UV-B was remarkably ameliorated with increased production of hyaluronic acid by treating fsCH to photoaged mice. Taken together, fsCH attenuated photoaging typical of deep wrinkles, epidermal thickening, and skin water loss, like NAG, RA, or GPH, through inhibiting collagen destruction and epidermal barrier impairment.

Estimating the Insertion Depth of a Peripherally Inserted Central Catheter in Newborns Using Weight and Gestational Age Measurements.

The objective of this study was to estimate the peripherally inserted central catheter (PICC) insertion depth in newborns. We retrospectively reviewed the records of 790 neonates who underwent PICC insertion for intravenous injections administered for 6 days or more following neonatal intensive care unit admission at our institution between January 2011 and October 2015. We analyzed patients' electronic medical records and chest standard radiographs. PICC insertion depths were calculated using the following equation: Insertion depth = Section + (ß1 × Body weight). The predicted equation was checked for accuracy using Bland-Altman plots. Of 835 included neonates, 790 (94.6%) had properly positioned PICCs. Forty-three of 45 unsuitable patients (5.4%) had catheters inserted into the cephalic veins. Of the 790 patients with correctly inserted catheter tips, regression equations and standard errors were calculated for the average insertion depth and timing of PICC insertion. The catheter depth increased with every 100 g of weight gain and week of gestational age. More than 90% of the 4 vessels incorporating PICCs were included within the standard deviation of ±2.0, indicating high predictive validity. This study established a standard for accurately measuring PICC insertion depths.

Mitochondrial dysfunction regulates the JAK-STAT pathway via LKB1-mediated AMPK activation ER-stress-independent manner.

Mitochondria affect cellular functions alone or in cooperation with other cellular organelles. Recent research has demonstrated the close relationship of mitochondria with the endoplasmic reticulum (ER), both at the physical and the functional level. In an effort to define the combined effect of mitochondrial dysfunction (MD) and ER stress in the proinflammatory activities of macrophages, the human macrophage-like monocytic leukemia cell line THP-1 was treated with mitochondrial electron transport chain (ETC) blockers, and changes in the cellular responses upon stimulation by interferon (IFN)-γ were analyzed. Inducing mitochondrial dysfunction (MD) with ETC blockers resulted in suppression of IFN-induced activation of JAK1 and STAT1/3, as well as the expression of STAT1-regulated genes. In addition, experiments utilizing pharmacological modulators of adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) and liver kinase B1 (LKB1)-deficient HeLa cells demonstrated that these suppressive effects are mediated by the LKB1-AMPK pathway. Treatment with pharmacological inhibitors of ER stress sensors failed to affect these processes, thus indicating that involvement of ER stress is not required. These results indicate that MD, induced by blocking the ETC, affects IFN-induced activation of JAK-STAT and associated inflammatory changes in THP-1 cells through the LKB1-AMPK pathway independently of ER stress.

Novel Small Molecule Targeting the Hemagglutinin Stalk of Influenza Viruses.

Combating influenza is one of the perennial global public health issues to be managed. Antiviral drugs are useful for the treatment of influenza in the absence of an appropriate vaccine. However, the appearance of resistant strains necessitates a constant search for new drugs. In this study, we investigated novel anti-influenza drug candidates using in vitro and in vivo assays. We identified anti-influenza hit compounds using a high-throughput screening method with a green fluorescent protein-tagged recombinant influenza virus. Through subsequent analyses of their cytotoxicity and pharmacokinetic properties, one candidate (IY7640) was selected for further evaluation. In a replication kinetics analysis, IY7640 showed greater inhibitory effects during the early phase of viral infection than the viral neuraminidase inhibitor oseltamivir. In addition, we observed that hemagglutinin (HA)-mediated membrane fusion was inhibited by IY7640 treatment, indicating that the HA stalk region, which is highly conserved across various (sub)types of influenza viruses, may be the molecular target of IY7640. In an escape mutant analysis in cells, amino acid mutations were identified at the HA stalk region of the 2009 pandemic H1N1 (pH1N1) virus. Even though the in vivo efficacy of IY7640 did not reach complete protection in a lethal challenge study in mice, these results suggest that IY7640 has potential to be developed as a new type of anti-influenza drug.IMPORTANCE Anti-influenza drugs with broad-spectrum efficacy against antigenically diverse influenza viruses can be highly useful when no vaccines are available. To develop new anti-influenza drugs, we screened a number of small molecules and identified a strong candidate, IY7640. When added at the time of or after influenza virus infection, IY7640 was observed to successfully inhibit or reduce viral replication in cells. We subsequently discovered that IY7640 targets the stalk region of the influenza HA protein, which exhibits a relatively high degree of amino acid sequence conservation across various (sub)types of influenza viruses. Furthermore, IY7640 was observed to block HA-mediated membrane fusion of H1N1, H3N2, and influenza B viruses in cells. Although it appears less effective against strains other than H1N1 subtype viruses in a challenge study in mice, we suggest that the small molecule IY7640 has potential to be optimized as a new anti-influenza drug.