Precessing jet nozzle connecting to a spinning black hole in M87.

The nearby radio galaxy M87 offers a unique opportunity to explore the connections between the central supermassive black hole and relativistic jets. Previous studies of the inner region of M87 revealed a wide opening angle for the jet originating near the black hole1-4. The Event Horizon Telescope resolved the central radio source and found an asymmetric ring structure consistent with expectations from general relativity5. With a baseline of 17 years of observations, there was a shift in the jet's transverse position, possibly arising from an 8- to 10-year quasi-periodicity3. However, the origin of this sideways shift remains unclear. Here we report an analysis of radio observations over 22 years that suggests a period of about 11 years for the variation in the position angle of the jet. We infer that we are seeing a spinning black hole that induces the Lense-Thirring precession of a misaligned accretion disk. Similar jet precession may commonly occur in other active galactic nuclei but has been challenging to detect owing to the small magnitude and long period of the variation.

Fcg-Former: Identification of Functional Groups in FTIR Spectra Using Enhanced Transformer-Based Model.

Deep learning (DL) is becoming more popular as a useful tool in various scientific domains, especially in chemistry applications. In the infrared spectroscopy field, where identifying functional groups in unknown compounds poses a significant challenge, there is a growing need for innovative approaches to streamline and enhance analysis processes. This study introduces a transformative approach leveraging a DL methodology based on transformer attention models. With a data set containing approximately 8677 spectra, our model utilizes self-attention mechanisms to capture complex spectral features and precisely predict 17 functional groups, outperforming conventional architectures in both functional group prediction accuracy and compound-level precision. The success of our approach underscores the potential of transformer-based methodologies in enhancing spectral analysis techniques.

Randomized, Double-Blind, Active-Controlled Phase 3 Study to Evaluate Efficacy and Safety of Zastaprazan Compared With Esomeprazole in Erosive Esophagitis.

INTRODUCTION: Zastaprazan is a potent potassium-competitive acid blocker developed to treat gastroesophageal reflux disease. The aim of this study was to evaluate the efficacy and safety of zastaprazan compared with esomeprazole in patient with erosive esophagitis (EE). METHODS: A phase III, multicenter, randomized, double-blind, noninferiority clinical study was conducted with 300 subjects with confirmed EE. Subjects were randomized to receive zastaprazan 20 mg or esomeprazole 40 mg once daily up to 8 weeks. The primary end point was the cumulative proportion of subject with healed EE confirmed by endoscopy at week 8. The secondary end points included the healing rate at week 4, symptom response, and quality of life assessment. Safety profiles and serum gastrin levels were also assessed. RESULTS: In the full analysis set, the cumulative healing rate at week 8 were 97.92% (141/144) for zastaprazan and 94.93% (131/138) ( P = 0.178) for esomeprazole. The healing rate at week 4 in the zastaprazan group was higher than the esomeprazole group (95.14% [137/144] vs 87.68% [121/138]; P = 0.026). There was no significant difference between groups in healing rates (the per-protocol set) at week 8 and week 4, symptom responses, quality of life assessments, and safety profiles. In addition, serum gastrin levels increased during treatment in both groups, with a significant difference between the 2 groups ( P = 0.047), but both decreased after treatment. DISCUSSION: An 8-week therapy of zastaprazan 20 mg is noninferior to esomeprazole 40 mg in subjects with predominantly low-grade EE. The healing rate at week 4 appears to be higher for zastaprazan than esomeprazole.

Gastroparesis might not be uncommon in patients with diabetes mellitus in a real-world clinical setting: a cohort study.

BACKGROUND: This study investigated the frequency of diabetic gastroparesis and associated risk factors in a real-world clinical setting. METHODS: This retrospective cross-sectional study included patients who underwent assessments of solid gastric emptying time (GET) by technetium-99 m scintigraphy between May 2019 and December 2020. We categorized patients into three groups according to gastric retention of technetium-99 m: rapid (< 65% at 1 h or < 20% at 2 h), normal (≤60% at 2 h and/or ≤ 10% at 4 h), and delayed (> 60% at 2 h and/or > 10% at 4 h). RESULTS: Patients with diabetes mellitus (DM) were more likely to show abnormal GET than those without DM (119 [70.8%] vs. 16 [44.4%]). The mean glycated A1c was 10.3% in DM patients. DM patients with normal GET were significantly younger (57.2 years, P = 0.044) than those with delayed (65.0 years) or rapid GET (60.2 years). Fasting glucose levels were the lowest in the normal GET group and the highest in the rapid GET group (delayed: 176.3 mg/dL, normal: 151.2 mg/dL, rapid: 181.0 mg/dL, P = 0.030). However, glycated A1c was not significantly different among the delayed, normal, and rapid GET groups in patients with DM. Patients with delayed and rapid GET showed a higher frequency of retinopathy (6.0 vs. 15.5%, P = 0.001) and peripheral neuropathy (11.3 vs. 24.4%, P = 0.001) than those with normal GET. In the multinomial logistic regression analysis, retinopathy demonstrated a positive association with delayed GET, while nephropathy showed a significant negative correlation. CONCLUSION: DM gastroparesis in the clinical setting was not uncommon. Abnormal GET, including delayed and rapid GET, was associated with DM retinopathy or peripheral neuropathy.

Novel Water Probe for High-Frequency Focused Transducer Applied to Scanning Acoustic Microscopy System: Simulation and Experimental Investigation.

A scanning acoustic microscopy (SAM) system is a common non-destructive instrument which is used to evaluate the material quality in scientific and industrial applications. Technically, the tested sample is immersed in water during the scanning process. Therefore, a robot arm is incorporated into the SAM system to transfer the sample for in-line inspection, which makes the system complex and increases time consumption. The main aim of this study is to develop a novel water probe for the SAM system, that is, a waterstream. During the scanning process, water was supplied using a waterstream instead of immersing the sample in the water, which leads to a simple design of an automotive SAM system and a reduction in time consumption. In addition, using a waterstream in the SAM system can avoid contamination of the sample due to immersion in water for long-time scanning. Waterstream was designed based on the measured focal length calculation of the transducer and simulated to investigate the internal flow characteristics. To validate the simulation results, the waterstream was prototyped and applied to the TSAM-400 and W-FSAM traditional and fast SAM systems to successfully image some samples such as carbon fiber-reinforced polymers, a printed circuit board, and a 6-inch wafer. These results demonstrate the design method of the water probe applied to the SAM system.

Design and Micro-Fabrication of Focused High-Frequency Needle Transducers for Medical Imaging.

In this study, we report an advanced fabrication technique to develop a miniature focused needle transducer. Two different types of high-frequency (100 MHz) transducers were fabricated using the lead magnesium niobate-lead titanate (PMN-0.3PT) and lithium niobate (LiNbO3) single crystals. In order to enhance the transducer's performance, a unique mass-spring matching layer technique was adopted, in which gold and parylene play the roles of the mass layer and spring layer, respectively. The PMN-0.3PT transducer had a 103 MHz center frequency with a -6 dB bandwidth of 52%, and a signal-to-noise ratio (SNR) of 42 dB. The center frequency, -6 dB bandwidth, and SNR of the LiNbO3 transducer were 105 MHz, 66%, and 44 dB, respectively. In order to compare and evaluate the transducers' performances, an ultrasonic biomicroscopy (UBM) imaging on the fish eye was performed. The results showed that the LiNbO3 transducer had a better contrast resolution compared to the PMN-0.3PT transducer. The fabricated transducer showed an excellent performance with high-resolution corneal epithelium imaging of the experimental fish eye. These interesting findings are useful for the future biomedical implementation of the fabricated transducers in the field of high-resolution ultrasound imaging and diagnosis purpose.

Improved Depth-of-Field Photoacoustic Microscopy with a Multifocal Point Transducer for Biomedical Imaging.

In this study, a photoacoustic microscopy (PAM) system based on a multifocal point (MFP) transducer was fabricated to produce a large depth-of-field tissue image. The customized MFP transducer has seven focal points, distributed along with the transducer's axis, fabricated by separate spherically-focused surfaces. These surfaces generate distinct focal zones that are overlapped to extend the depth-of-field. This design allows extending the focal zone of 10 mm for the 11 MHz MFP transducer, which is a great improvement over the 0.48 mm focal zone of the 11 MHz single focal point (SFP) transducer. The PAM image penetration depths of a chicken-hemoglobin phantom using SFP and MFP transducers were measured as 5 mm and 8 mm, respectively. The significant increase in the PAM image-based penetration depth of the chicken-hemoglobin phantom was a result of using the customized MFP transducer.

Antibiofilm and antivirulence properties of chitosan-polypyrrole nanocomposites to Pseudomonas aeruginosa.

Pseudomonas aeruginosa is an opportunistic human pathogen which exhibits its property of pathogenesis due to several factors, including the formation of biofilm and production of several virulence factors. Development of resistance properties against antibiotics leads to the discovery of certain alternative strategies to combat its pathogenesis. In the present study, a highly stable, biocompatible and water soluble nanocomposites (NCs) are synthesized from chitosan (CS) and the polypyrrole (PPy). The resultant chitosan-polypyrrole nanocomposites (CS-PPy NCs) inhibit the establishment of biofilm and also eradicate the preformed matured biofilm formed by P. aeruginosa. CS-PPy NCs inhibit the hemolytic and protease activities of P. aeruginosa. The NCs significantly reduce the production of many virulence factors such as pyocyanin, pyroverdine and rhamnolipid. CS-PPy NCs also suppress the bacterial motility such as swimming and swarming. The present study showed that highly stable CS-PPy NCs act as a potent antibiofilm and antivirulence drug for the treatment of P. aeruginosa infection.

Synthesis and characterization of chitosan oligosaccharide-capped gold nanoparticles as an effective antibiofilm drug against the Pseudomonas aeruginosa PAO1.

The infection caused by Pseudomonas aeruginosa is a serious concern in human health. The bacterium is an opportunistic pathogen which has been reported to cause nosocomial and chronic infections through biofilm formation and synthesis of several toxins and virulence factors. Furthermore, the formation of biofilm by P. aeruginosa is known as one of the resistance mechanisms against conventional antibiotics. Natural compounds from marine resources have become one of the simple, cost-effective, biocompatible and non-toxicity for treating P. aeruginosa biofilm-related infections. Furthermore, hybrid formulation with nanomaterials such as nanoparticles becomes an effective alternative strategy to minimize the drug toxicity problem and cytotoxicity properties. For this reason, the present study has employed chitosan oligosaccharide for the synthesis of chitosan oligosaccharide-capped gold nanoparticles (COS-AuNPs). The synthesized COS-AuNPs were then characterized by using UV-Visible spectroscopy, Dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), Field emission transmission electron microscopy (FE-TEM), and Energy dispersive X-ray diffraction (EDX). The synthesized COS-AuNPs were applied for inhibiting P. aeruginosa biofilm formation. Results have shown that COS-AuNPs exhibited inhibition to biofilm as well as eradication to pre-existing mature biofilm. Simultaneously, COS-AuNPs were also able to reduce bacterial hemolysis and different virulence factors produced by P. aeruginosa. Overall, the present study concluded that the hybrid nanoformulation such as COS-AuNPs could act as a potential agent to exhibit inhibitory properties against the P. aeruginosa pathogenesis arisen from biofilm formation.

Synthesis of Silica-Coated Magnetic Hydroxyapatite Composites for Drug Delivery Applications.

We have prepared a core-shell magnetic silica-coated hydroxyapatite, Fe3O4@SiO2@HAp composite materials for pH-responsive drug delivery applications. Captopril (Cap) and ibuprofen (Ibu) were chosen as model hydrophilic and hydrophobic drugs, respectively. The drugs were encapsulated into the Fe3O4@SiO2@HAp composite via electrostatic interactions with existing amine and carboxylic acid groups during calcium phosphate shell formation. The formation of calcium phosphate shell not only protects the encapsulated drugs from leaching but also controls the release rate of drugs from the composite system depending on various pH conditions. We have tested the release behavior of Cap and Ibu drugs under different pH conditions such as neutral pH (pH 7.4) and acidic pH (pH 5.0), respectively. The study result reveals that the synthesized Fe3O4@SiO2@HAp composite is suitable for release of both water soluble and water insoluble drugs based on a pH-responsive controlled manner.

Fucoidan-Stabilized Gold Nanoparticle-Mediated Biofilm Inhibition, Attenuation of Virulence and Motility Properties in Pseudomonas aeruginosa PAO1.

The emergence of antibiotic resistance in Pseudomonas aeruginosa due to biofilm formation has transformed this opportunistic pathogen into a life-threatening one. Biosynthesized nanoparticles are increasingly being recognized as an effective anti-biofilm strategy to counter P. aeruginosa biofilms. In the present study, gold nanoparticles (AuNPs) were biologically synthesized and stabilized using fucoidan, which is an active compound sourced from brown seaweed. Biosynthesized fucoidan-stabilized AuNPs (F-AuNPs) were subjected to characterization using UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), field emission transmission electron microscopy (FE-TEM), dynamic light scattering (DLS), and energy dispersive X-ray diffraction (EDX). The biosynthesized F-AuNPs were then evaluated for their inhibitory effects on P. aeruginosa bacterial growth, biofilm formation, virulence factor production, and bacterial motility. Overall, the activities of F-AuNPs towards P. aeruginosa were varied depending on their concentration. At minimum inhibitory concentration (MIC) (512 µg/mL) and at concentrations above MIC, F-AuNPs exerted antibacterial activity. In contrast, the sub-inhibitory concentration (sub-MIC) levels of F-AuNPs inhibited biofilm formation without affecting bacterial growth, and eradicated matured biofilm. The minimum biofilm inhibition concentration (MBIC) and minimum biofilm eradication concentration (MBEC) were identified as 128 µg/mL. Furthermore, sub-MICs of F-AuNPs also attenuated the production of several important virulence factors and impaired bacterial swarming, swimming, and twitching motilities. Findings from the present study provide important insights into the potential of F-AuNPs as an effective new drug for controlling P. aeruginosa-biofilm-related infections.

Design, Fabrication, and Evaluation of Multifocal Point Transducer for High-Frequency Ultrasound Applications.

The present study illustrates the design, fabrication, and evaluation of a novel multifocal point (MFP) transducer based on polyvinylidene fluoride (PVDF) film for high-frequency ultrasound application. The fabricated MFP surface was press-focused using a computer numerical control (CNC) machining tool-customized multi-spherical pattern object. The multi-spherical pattern has five spherical surfaces with equal area and connected continuously to have the same energy level at focal points. Center points of these spheres are distributed in a linear pattern with 1 mm distance between each two points. The radius of these spheres increases steadily from 10 mm to 13.86 mm. The designed MFP transducer had a center frequency of 50 MHz and a -6 dB bandwidth of 68%. The wire phantom test was conducted to study and demonstrate the advantages of this novel design. The obtained results for MFP transducer revealed a significant increase (4.3 mm) of total focal zone in the near-field and far-field area compared with 0.48 mm obtained using the conventional single focal point transducer. Hence, the proposed method is promising to fabricate MFP transducers for deeper imaging depth applications.

Species-specific role of gene-adjacent retroelements in human and mouse gastric carcinogenesis.

Helicobacter pylori (HP) infection promotes the recruitment of bone marrow stem cells into chronic gastritis lesions. Some of these marrow stem cells can differentiate into gastric epithelial cells and neoplastic cells. We propose that HP-associated methylation could stabilize trans-differentiation of marrow-derived stem cells and that an unstable methylation status is associated with a risk of gastric cancer. Pathobiologic behavior of experimental mouse gastric cancer is mild compared to invasive and metastatic human gastric cancer. Differences in epigenetic stabilization of adult cell phenotypes between humans and mice could provide a foundation to explore the development of invasive and metastatic gastric cancer. Retroelements are highly repetitive sequences that play an essential role in the generation of species diversity. In this review, we analyzed retroelements adjacent to human and mouse housekeeping genes and proposed a possible epigenetic mechanism for HP-associated carcinogenesis.

Marine natural pigments as potential sources for therapeutic applications.

In recent years, marine natural pigments have emerged as a powerful alternative in the various fields of food, cosmetic, and pharmaceutical industries because of their excellent biocompatibility, bioavailability, safety, and stability. Marine organisms are recognized as a rich source of natural pigments such as chlorophylls, carotenoids, and phycobiliproteins. Numerous studies have shown that marine natural pigments have considerable medicinal potential and promising applications in human health. In this review, we summarize the marine natural pigments as potential sources for therapeutic applications, including: antioxidant, anticancer, antiangiogenic, anti-obesity, anti-inflammatory activities, drug delivery, photothermal therapy (PTT), photodynamic therapy (PDT), photoacoustic imaging (PAI), and wound healing. Marine natural pigments will offer a better platform for future theranostic applications.

Fish bone peptide promotes osteogenic differentiation of MC3T3-E1 pre-osteoblasts through upregulation of MAPKs and Smad pathways activated BMP-2 receptor.

Fish bone, a by-product of fishery processing, is composed of protein, calcium, and other minerals. The objective of this study was to investigate the effects of a bioactive peptide isolated from the bone of the marine fish, Johnius belengerii, on the osteoblastic differentiation of MC3T3-E1 pre-osteoblasts. Post consecutive purification by liquid chromatography, a potent osteogenic peptide, composed of 3 amino acids, Lys-Ser-Ala (KSA, MW: 304.17 Da), was identified. The purified peptide promoted cell proliferation, alkaline phosphatase activity, mineral deposition, and expression levels of phenotypic markers of osteoblastic differentiation in MC3T3-E1 pre-osteoblast. The purified peptide induced phosphorylation of mitogen-activated protein kinases, including p38 mitogen-activated protein kinase, extracellular regulated kinase, and c-Jun N-terminal kinase as well as Smads. As attested by molecular modelling study, the purified peptide interacted with the core interface residues in bone morphogenetic protein receptors with high affinity. Thus, the purified peptide could serve as a potential pharmacological substance for controlling bone metabolism.

Coating Chitosan Thin Shells: A Facile Technique to Improve Dispersion Stability of Magnetoliposomes.

Magnetoliposomes (ML) have been emerging as a novel multifunctional nanoparticle with a wide range of biomedical and therapeutic applications over the past decade. Although the ML system has shown excellent performances, the stability and lipid peroxidation of liposomal components are still remaining as key issues and need to be solved for intensive applications. Changing zeta potential of nanoparticles' surface can be seen as a potential way to achieve the stable dispersion. In this work, we have employed the positive charged, abundant and cheap chitosan to coat ML in order to change the zeta potential of the ML system and examined the stability of chitosan@magnetoliposomes (CML) in long-term storage. The combining of pH-sensitive chitosan with temperature-sensitive phospholipid formed a novel pH- and temperature-sensitive nanoparticles which can be promisingly used as controllable drug release applications. These novel CML with chitosan thin shells showed excellent stability in long-term storage; meanwhile, the bare ML sample showed aggregations and forming micrometer-size particles. The CML system can achieve a drug encapsulation efficiency of nearly 50% and an enhanced drug release behavior under pH 5 at 45 °C.

Photothermal-triggered control of sub-cellular drug accumulation using doxorubicin-loaded single-walled carbon nanotubes for the effective killing of human breast cancer cells.

Single-walled carbon nanotubes (SWNTs) are often the subject of investigation as effective photothermal therapy (PTT) agents owing to their unique strong optical absorption. Doxorubicin (DOX)-loaded SWNTs (SWNTs-DOX) can be used as an efficient therapeutic agent for combined near infrared (NIR) cancer photothermal and chemotherapy. However, SWNTs-DOX-mediated induction of cancer cell death has not been fully investigated, particularly the reaction of DOX inside cancer cells by PTT. In this study, we examined how the SWNTs-DOX promoted effective MDA-MB-231 cell death compared to DOX and PTT alone. We successfully synthesized the SWNTs-DOX. The SWNTs-DOX exhibited a slow DOX release, which was accelerated by NIR irradiation. Furthermore, DOX released from the SWNTs-DOX accumulated inside the cells at high concentration and effectively localized into the MDA-MB-231 cell nucleus. A combination of SWNTs-DOX and PTT promoted an effective MDA-MB-231 cell death by mitochondrial disruption and ROS generation. Thus, SWNTs-DOX can be utilized as an excellent anticancer agent for early breast cancer treatment.

Rabbit model of tracheal stenosis using cylindrical diffuser.

BACKGROUND AND OBJECTIVE: Variable methods of animal model have been introduced to develop tracheal stenosis. However, none of the prior models allow for predictable determination of the grade of stenosis. This study sought to establish an animal model of tracheal stenosis by using a cylindrical diffuser and to evaluate the feasibility of a reproducible model. STUDY DESIGN/MATERIALS AND METHODS: A cylindrical diffuser was developed to have a 5 mm active segment to emit laser light circumferentially. Twenty one New Zealand white rabbits were enrolled in this study. The cylindrical diffuser was inserted transorally under bronchoscopic view and the diffused light was delivered to tracheal mucosa 2 cm below the level of vocal cord. Input power of irradiation was 10 W, 5 seconds in group A (n = 7), 10 W, 7 seconds in group B (n = 7), and 8 W, 5 seconds in group C (n = 7). The degree of tracheal stenosis was observed weekly and the rabbits were euthanized 4 weeks after the laser irradiation. RESULTS: The degree of stenosis in group B (90-98%) was significantly larger than that of group A (75-92%) (P = 0.004), while degree in group C (24-35%) was significantly smaller than that of group A (P < 0.001). Two rabbits of group A were euthanized at 3 weeks due to costal retraction. In group B, six rabbits died within 3 weeks after laser irradiation due to severe tracheal stenosis and tracheal malacia, while one rabbit was euthanized 16 days after the irradiation. All rabbits in group C survived up to 4 weeks. Survival between three groups showed significant difference (P = 0.001). CONCLUSION: The degree of stenosis was significantly different according to the delivered optical energy to tracheal mucosa. Therefore, the proposed model may be used in animal studies to emulate variable grades of tracheal stenosis. Lasers Surg. Med. 49:372-379, 2017. © 2016 Wiley Periodicals, Inc.

Synergistic Antibacterial Effects of Chitosan-Caffeic Acid Conjugate against Antibiotic-Resistant Acne-Related Bacteria.

The object of this study was to discover an alternative therapeutic agent with fewer side effects against acne vulgaris, one of the most common skin diseases. Acne vulgaris is often associated with acne-related bacteria such as Propionibacteriumacnes, Staphylococcusepidermidis, Staphylococcusaureus, and Pseudomonasaeruginosa. Some of these bacteria exhibit a resistance against commercial antibiotics that have been used in the treatment of acne vulgaris (tetracycline, erythromycin, and lincomycin). In the current study, we tested in vitro antibacterial effect of chitosan-phytochemical conjugates on acne-related bacteria. Three chitosan-phytochemical conjugates used in this study exhibited stronger antibacterial activity than that of chitosan (unmodified control). Chitosan-caffeic acid conjugate (CCA) showed the highest antibacterial effect on acne-related bacteria along with minimum inhibitory concentration (MIC; 8 to 256 µg/mL). Additionally, the MIC values of antibiotics against antibiotic-resistant P. acnes and P.aeruginosa strains were dramatically reduced in combination with CCA, suggesting that CCA would restore the antibacterial activity of the antibiotics. The analysis of fractional inhibitory concentration (FIC) indices clearly revealed a synergistic antibacterial effect of CCA with antibiotics. Thus, the median sum of FIC (∑FIC) values against the antibiotic-resistant bacterial strains ranged from 0.375 to 0.533 in the combination mode of CCA and antibiotics. The results of the present study suggested a potential possibility of chitosan-phytochemical conjugates in the control of infections related to acne vulgaris.

Marine microorganisms as potential biofactories for synthesis of metallic nanoparticles.

The use of marine microorganisms as potential biofactories for green synthesis of metallic nanoparticles is a relatively new field of research with considerable prospects. This method is eco-friendly, time saving, and inexpensive and can be easily scaled up for large-scale synthesis. The increasing need to develop simple, nontoxic, clean, and environmentally safe production methods for nanoparticles and to decrease environmental impact, minimize waste, and increase energy productivity has become important in this field. Marine microorganisms are tiny organisms that live in marine ecosystems and account for >98% of biomass of the world's ocean. Marine microorganisms synthesize metallic nanoparticles either intracellularly or extracellularly. Marine microbially-produced metallic nanoparticles have received considerable attention in recent years because of their expected impact on various applications such as medicine, energy, electronic, and space industries. The present review discusses marine microorganisms as potential biofactories for the green synthesis of metallic nanoparticles and their potential applications.