Morphology and ITS sequences provide insights into the phylogeny of Tongoloa (Apiaceae) from China.

BACKGROUND: Tongoloa is a genus comprising approximately 20 species, primarily distributed in the mountainous regions of southwest China. The insufficiency of specimen materials and morphological similarities among species render it a taxonomically challenging genus within the Apiaceae family. To elucidate the phylogenetic relationships and taxonomy of Chinese Tongoloa, this study utilized a total of 115 nrITS sequences, including 47 recently obtained sequences, for phylogenetic reconstruction. RESULTS: Phylogenetic relationships reconstructed from ITS sequences indicate that the East Asia Clade and the Komarovia Clade are sister groups, and Tongoloa belongs to the East Asia Clade. Species of Tongoloa are subdivided into 3 distinct groups, all sharing similar fruit morphologies and are clearly differentiated from related taxa. Several Tongoloa-like members classified under other genera are interpreted to be closely related to Tongoloa. Morphological and molecular data indicate that Tongoloa, Sinolimprichtia subclade and Chinese Trachydium subclade are separate yet genetically contiguous taxa. It is confirmed that Tongoloa zhongdianensis belongs to the Hymenidium Clade, while Sinocarum is classified within the Acronema Clade. Two new taxa are found in the Hengduan Mountains. CONCLUSION: Tongoloa is a genus within the East Asia Clade of Apiaceae, and the phylogeny reconstructed based on ITS sequences divides it into 3 main groups. By integrating fruit morphology and molecular phylogenetic analyses, we preliminary clarified the intricate taxonomic relationships among Tongoloa and related taxa. These results provide valuable opportunities for a deeper understanding of the phylogeny of Tongoloa.

Prenatal exposure to PM2.5 and childhood body mass index growth trajectories from birth to 6 years old.

This study aimed to determine the relationships between prenatal PM2.5 exposure and childhood growth trajectories during the first 6 years of life. A total of 47,625 pairs of mothers and children were recruited from a prospective birth cohort conducted between 2011 and 2013 in Wuhan, China, and followed for 6 years. We used the group-based trajectory models to classify the population into three trajectory groups: slow growth (n = 13,671, 28.7%), normal growth (n = 29,736, 62.4%), and rapid growth (n = 4218, 8.9%). Multinomial logistic regression models were used to determine the associations of prenatal PM2.5 exposure and childhood growth trajectories. Compared to normal growth trajectory, increased PM2.5 exposure in trimester 1, trimester 2 and the entire pregnancy showed significant associations with an increased risk of the slow growth trajectory but reduced the risk for the rapid growth trajectory, significant association of prenatal PM2.5 exposure with rapid growth trajectory was only observed in the trimester 3. Stratified analyses displayed relatively stronger associations among those mothers with maternal age over 35 years, pre-pregnancy BMI ≥ 25 kg/m2, and previous delivery experience. Prenatal exposure to PM2.5, particularly during the midpoint period of pregnancy, was more likely to have a slow growth trajectory and a lower risk of rapid growth trajectory. Maternal age, pre-pregnancy BMI, and previous delivery experience might modify these associations.

Phellodendron chinense C.K.Schneid: An in vitro study on its anti-Helicobacter pylori effect.

ETHNOPHARMACOLOGICAL RELEVANCE: Phellodendron chinense C.K.Schneid(P. chinense Schneid) is known in TCM as Huang Bo, is traditionally used to support gastrointestinal function and alleviate stomach-related ailments, including gastric ulcer bleeding and symptoms of gastroesophageal reflux disease. Helicobacter pylori (H. pylori) is classified by the WHO as a Group 1 carcinogen. However, the specific activity and mechanism of action of P. chinense Schneid against H. pylori infection remain unclear. It has been noted that Huangjiu processing may alter the bitter and cold properties of P. chinense Schneid, but its effect on antimicrobial activity requires further investigation. Additionally, it remains uncertain whether berberine is the sole antimicrobial active component of P. chinense Schneid. AIM OF STUDY: This study aims to elucidate the anti-H. pylori infection activity of P. chinense Schneid, along with its mechanism of action and key antimicrobial active components. MATERIALS AND METHODS: Phytochemical analysis was carried out by UPLC-MS/MS. HPLC was employed to quantify the berberine content of the extracts. Antimicrobial activity was assessed using the micro broth dilution method. Morphology was observed using SEM. The impact on urease activity was analyzed through in vitro urease enzyme kinetics. RT-qPCR was employed to detect the expression of virulence genes, including adhesin, flagellum, urease, and cytotoxin-related genes. The adhesion effect was evaluated by immunofluorescence staining and agar culture. RESULTS: P. chinense Schneid exhibited strong antimicrobial activity against both antibiotic-sensitive and resistant H. pylori strains, with MIC ranging from 40 to 160 µg/mL. Combination with amoxicillin, metronidazole, levofloxacin, and clarithromycin did not result in antagonistic effects. P. chinense Schneid induced alterations in bacterial morphology and structure, downregulated the expression of various virulence genes, and inhibited urease enzyme activity. In co-infection systems, P. chinense Schneid significantly attenuated H. pylori adhesion and urease relative content, thereby mitigating cellular damage caused by infection. Huangjiu processing enhanced the anti-H. pylori activity of P. chinense Schneid. Besides berberine, P. chinense Schneid contained seven other components with anti-H. pylori activity, with palmatine exhibiting the strongest activity, followed by jatrorrhizine. CONCLUSIONS: This study sheds light on the potential therapeutic mechanisms of P. chinense Schneid against H. pylori infection, demonstrating its capacity to disrupt bacterial structure, inhibit urease activity, suppress virulence gene transcription, inhibit adhesion, and protect host cells. The anti-H. pylori activity of P. chinense Schneid was potentiated by Huangjiu processing, and additional components beyond berberine were identified as possessing strong anti-H. pylori activity. Notably, jatrorrhizine, a core component of P. chinense Schneid, exhibited significant anti-H. pylori activity, marking a groundbreaking discovery.

Studies on the mechanisms of Helicobacter pylori inhibition by Syzygium aromaticum aqueous extract.

BACKGROUND: The aqueous extract of the dried buds of Syzygium aromaticum (SAAE) have the potential to alleviate Helicobacter pylori infection, but the specific molecular mechanism has not been fully elucidated. PURPOSE: This study aimed to investigate the underlying mechanisms of SAAE on H. pylori pathogenicity. METHODS: The inhibitory kinetics and anti-H. pylori adhesive capacity assays were conducted to examine the effects of SAAE on the growth and adhesive capability of H. pylori. The H. pylori outer membrane vesicles (OMVs) were purified from the culture supernatant through high-speed centrifugation, filtration, and two rounds of ultracentrifugation. Their characteristics and protein composition were then identified using transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and qualitative proteomics study. Subsequently, the effect of SAAE on the pathogenicity of H. pylori OMVs was investigated using the Griess reagent assay, enzyme-linked immunosorbent assay (ELISA), quantitative proteomics study, TEM, and western blotting assay. RESULTS: SAAE exhibited inhibitory effects on H. pylori growth and adhesion. The isolated H. pylori OMVs showed particle size of 27-242 nm and Zeta potential of -9.67 ± 0.53 mV. A total of 599 proteins were identified in the OMVs. Proteomics study indicated that the differential expressed proteins induced by OMVs with or without SAAE commonly enriched in P53 and autophagy pathways. Besides, SAAE counteracted the increased production of pro-inflammatory cytokines and attenuated the induction of cell autophagy caused by H. pylori OMVs. Furthermore, SAAE normalized the abnormal regulation of downstream targets (AIFM2 and IGFBP3) in the P53 signaling pathway caused by H. pylori OMVs. CONCLUSION: SAAE can inhibit the growth and adhesion of H. pylori, reduce the inflammation and autophagy induced by H. pylori OMVs, and combated the abnormal regulation of P53 signaling pathway caused by H. pylori OMVs. These findings may help elucidate the mechanisms through which SAAE reduces the pathogenicity of H. pylori.

Thermal-tagging photoacoustic remote sensing flowmetry.

Ultrasound coupling is one of the critical challenges for traditional photoacoustic (or optoacoustic) microscopy (PAM) techniques transferred to the clinical examination of chronic wounds and open tissues. A promising alternative potential solution for breaking the limitation of ultrasound coupling in PAM is photoacoustic remote sensing (PARS), which implements all-optical non-interferometric photoacoustic measurements. Functional imaging of PARS microscopy was demonstrated from the aspects of histopathology and oxygen metabolism, while its performance in hemodynamic quantification remains unexplored. In this Letter, we present an all-optical thermal-tagging flowmetry approach for PARS microscopy and demonstrate it with comprehensive mathematical modeling and ex vivo and in vivo experimental validations. Experimental results demonstrated that the detectable range of the blood flow rate was from 0 to 12 mm/s with a high accuracy (measurement error:±1.2%) at 10-kHz laser pulse repetition rate. The proposed all-optical thermal-tagging flowmetry offers an effective alternative approach for PARS microscopy realizing non-contact dye-free hemodynamic imaging.

1,3,6-Trigalloylglucose: A Novel Potent Anti-Helicobacter pylori Adhesion Agent Derived from Aqueous Extracts of Terminalia chebula Retz.

1,3,6-Trigalloylglucose is a natural compound that can be extracted from the aqueous extracts of ripe fruit of Terminalia chebula Retz, commonly known as "Haritaki". The potential anti-Helicobacter pylori (HP) activity of this compound has not been extensively studied or confirmed in scientific research. This compound was isolated using a semi-preparative liquid chromatography (LC) system and identified through Ultra-high-performance liquid chromatography-MS/MS (UPLC-MS/MS) and Nuclear Magnetic Resonance (NMR). Its role was evaluated using Minimum inhibitory concentration (MIC) assay and minimum bactericidal concentration (MBC) assay, scanning electron microscope (SEM), inhibiting kinetics curves, urea fast test, Cell Counting Kit-8 (CCK-8) assay, Western blot, and Griess Reagent System. Results showed that this compound effectively inhibits the growth of HP strain ATCC 700392, damages the HP structure, and suppresses the Cytotoxin-associated gene A (Cag A) protein, a crucial factor in HP infection. Importantly, it exhibits selective antimicrobial activity without impacting normal epithelial cells GES-1. In vitro studies have revealed that 1,3,6-Trigalloylglucose acts as an anti-adhesive agent, disrupting the adhesion of HP to host cells, a critical step in HP infection. These findings underscore the potential of 1,3,6-Trigalloylglucose as a targeted therapeutic agent against HP infections.

In vitro anti-Helicobacter pylori activity and the underlining mechanism of an empirical herbal formula - Hezi Qingyou.

Background: Helicobacter pylori (H. pylori) is thought to primarily colonize the human stomach and lead to various gastrointestinal disorders, such as gastritis and gastric cancer. Currently, main eradication treatment is triple or quadruple therapy centered on antibiotics. Due to antibiotic resistance, the eradication rate of H. pylori is decreasing gradually. Therefore, searching for anti-H. pylori drugs from herbal sources has become a strategy for the treatment. Our team proposed a Hezi Qingyou Formula (HZQYF), composed of Chebulae Fructus, Ficus hirta Vahl and Cloves, and studied its anti-H. pylori activity and mechanism. Methods: Chemical components of HZQYF were studied using UHPLC-MS/MS and HPLC. Broth microdilution method and agar dilution method were used to evaluate HZQYF's antibacterial activity. The effects of HZQYF on expression of adhesion genes (alpA, alpB, babA), urease genes (ureE, ureF), and flagellar genes (flaA, flaB) were explored using Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR) technology. Effects on morphology and permeability of the extracellular membrane were studied using scanning electron microscopy (SEM) and N-phenylnaphthalen-1-amine (NPN) uptake. Effect on urease activity was studied using a urease kinetics analysis in vitro. Immunofluorescence staining method was used to examine the effect on adhesion. Western blot was used to examine the effect on cagA protein. Results: Minimum inhibitory concentration (MIC) values of the formula against H. pylori clinical strains and standard strains were 80-160 µg/mL, and minimum bactericidal concentration (MBC) values were 160-320 µg/mL. The formula could down-regulate the expression of adhesion genes (alpA, alpB, babA), urease genes (ureE, ureF) and flagellar genes (flaA, flaB), change the morphology of H. pylori, increase its extracellular membrane permeability, and decrease its urease activity. Conclusion: Present studies confirmed that HZQYF had promising in vitro anti-H. pylori activities and demonstrated its possible mechanism of action by down-regulating the bacterial adhesion, urease, and flagellar gene expression, which provided scientific bases for further clinical investigations.

Self-injury and suicidal ideation among Chinese adolescents involved in different subtypes of aggression: The role of gender.

BACKGROUND: Although aggression associated self-injury and suicidal ideation, but the specific impact of different subtypes of aggression is unclear. Therefore, the current study aims to quantify the associations between five subtypes of aggression, self-injury, and suicidal ideation in Chinese adolescents. METHOD: A total of 18,532 students were recruited in grades 7 to 12 using a stratified cluster sampling across five representative provinces in China. The Functional Assessment of Self-Mutilation (CH-FASM) and Buss and Warren's Aggression Questionnaire (BWAQ) assess self-injury and aggression, respectively. RESULTS: During the last year, the proportion of self-injury, suicidal ideation, and self-injury plus suicidal ideation (SSI) were 13.4 %, 10.0 %, 12.4 %, respectively. Multivariate logistic regression indicated that hostility was associated with self-injury-only (OR = 1.033, 95 % CI = 1.021-1.044), suicidal ideation-only (OR = 1.075, 95 % CI = 1.061-1.088), and SSI (OR = 1.100, 95 % CI = 1.087-1.114) (all P < 0.001) across five subtypes of aggression. In gender stratification, physical aggression was risk factor for self-injury-only, suicidal ideation-only, and SSI (OR = 1.028, 95 % CI = 1.018-1.037, P < 0.001) in females. While anger was association with self-injury-only and suicidal ideation-only in males (P < 0.05). LIMITATIONS: This study was a cross-sectional design and self-reported questionnaire. CONCLUSION: Hostility is a strong predictor of self-injury and suicidal ideation across five subtypes of aggression. There are gender differences in relationships. Prevention programs for adolescents' self-injury and suicidal ideation should consider different subtypes of aggression and gender differences.

The symbiont Wolbachia alleviates pesticide susceptibility in the two-spotted spider mite Tetranychus urticae through enhanced host detoxification pathways.

The two-spotted spider mite (Tetranychus urticae) is one of the most well-known pesticide-resistant agricultural pests, with resistance often attributed to changes such as target-site mutations and detoxification activation. Recent studies show that pesticide resistance can also be influenced by symbionts, but their involvement in this process in spider mites remains uncertain. Here, we found that infection with Wolbachia, a well-known bacterial reproductive manipulator, significantly increased mite survival after exposure to the insecticides abamectin, cyflumetofen, and pyridaben. Wolbachia-infected (WI) mites showed higher expression of detoxification genes such as P450, glutathione-S-transferase (GST), ABC transporters, and carboxyl/cholinesterases. RNA interference experiments confirmed the role of the two above-mentioned detoxification genes, TuCYP392D2 and TuGSTd05, in pesticide resistance. Increased GST activities were also observed in abamectin-treated WI mites. In addition, when wild populations were treated with abamectin, WI mites generally showed better survival than uninfected mites. However, genetically homogeneous mites with different Wolbachia strains showed similar survival. Finally, abamectin treatment increased Wolbachia abundance without altering the mite's bacterial community. This finding highlights the role of Wolbachia in orchestrating pesticide resistance by modulating host detoxification. By unraveling the intricate interplay between symbionts and pesticide resistance, our study lays the groundwork for pioneering strategies to combat agricultural pests.

High-Performance PMN-PT Single-Crystal-Based 1-3 Composite Transducer Integrated with a Biopsy Needle.

To address the need for high-resolution imaging in lung nodule detection and overcome the limitations of the shallow imaging depth associated with high-frequency ultrasound and the complex structure of lung tissue, we successfully integrated 50 MHz ultrasound transducers with 18-gauge biopsy needles. Featuring a miniaturized size of 0.6 × 0.5 × 0.5 mm3, the 50 MHz micromachined 1-3 composite transducer was tested to perform mechanical scanning of a nodule within a lung-tissue-mimicking phantom in vitro. The high-frequency transducer demonstrated the ability to achieve imaging with an axial resolution of 30 µm for measuring nodule edges. Moreover, the integrated biopsy needle prototype exhibited high accuracy (1.74% discrepancy) in estimating nodule area compared to actual dimensions in vitro. These results underscore the promising potential of biopsy-needle-integrated transducers in enhancing the accuracy of endoscopic ultrasound-guided fine needle aspiration biopsy (EUS-FNA) for clinical applications.

Unraveling the complex roles of macrophages in obese adipose tissue: an overview.

Macrophages, a heterogeneous population of innate immune cells, exhibit remarkable plasticity and play pivotal roles in coordinating immune responses and maintaining tissue homeostasis within the context of metabolic diseases. The activation of inflammatory macrophages in obese adipose tissue leads to detrimental effects, inducing insulin resistance through increased inflammation, impaired thermogenesis, and adipose tissue fibrosis. Meanwhile, adipose tissue macrophages also play a beneficial role in maintaining adipose tissue homeostasis by regulating angiogenesis, facilitating the clearance of dead adipocytes, and promoting mitochondrial transfer. Exploring the heterogeneity of macrophages in obese adipose tissue is crucial for unraveling the pathogenesis of obesity and holds significant potential for targeted therapeutic interventions. Recently, the dual effects and some potential regulatory mechanisms of macrophages in adipose tissue have been elucidated using single-cell technology. In this review, we present a comprehensive overview of the intricate activation mechanisms and diverse functions of macrophages in adipose tissue during obesity, as well as explore the potential of drug delivery systems targeting macrophages, aiming to enhance the understanding of current regulatory mechanisms that may be potentially targeted for treating obesity or metabolic diseases.

Switchable Two-Dimensional AND and Exclusive OR Operation Based on Dual-Wavelength Metasurfaces.

Logic operation serves as the foundation and core element of computing networks; it will bring huge vitality to advanced information processing with its adaptation in the optical domain. As fundamental logic operations, AND and exclusive OR (XOR) operations serve a multitude of purposes, such as their ability to cooperate in enabling image processing and interpretation. Here, we propose and experimentally demonstrate a wavelength multiplexed AND and XOR function based on metasurfaces. By combining two cosine gratings with distinct frequencies and an initial phase difference of π/2, we extract the similarities and differences between two input images simultaneously by illuminating them with 445 and 633 nm wavelengths. Additionally, we explore its potential in information encryption, where overall security is enhanced by distributing distinct parts of initial information and encoded keys to different receivers. This design possesses the benefits of convenient mode switching and high-quality imaging, facilitating advanced applications in pattern recognition, machine vision, medical diagnosis, etc.

Mobile phone addiction and suicide behaviors among Chinese adolescents: The mediation of poor sleep quality.

Background and aims: Mobile phone addiction (MPA) is emerging among adolescents, especially during the COVID-19 pandemic. Nevertheless, there is a dearth of knowledge regarding the correlation between MPA and suicide behaviors and its mechanism. The objective of the current study is exploring the direct effect of MPA on suicide behaviors and the indirect effect through poor sleep quality. Methods: A total of 18,900 Chinese adolescents aged 12 to 18 were recruited via a multi-stage cluster sampling method. Results: The prevalence of MPA and poor sleep quality was 26.2 and 23.1%, respectively. During the past year, 24.4% participants were involved in suicide behaviors. Specifically, suicide ideators, suicide planners, and suicide attempters were 10.7, 8.4, and 5.3%, respectively. Particularly, rural females had the highest prevalence of suicide behaviors, MPA, and poor sleep quality. Logistic regression analysis showed that MPA was significantly associated with suicide ideators (OR = 1.22, 95% CI: 1.09-1.37, p < 0.001) and planners (OR = 1.18, 95% CI: 1.04-1.34, p < 0.05), but not for suicide attempters (p > 0.05). Structural equation modelling demonstrated that MPA had direct effect on suicide behaviors (ß = 0.145, 95% CI = 0.127-0.160), and poor sleep quality partially mediated the relationship (the mediating ratio was 46.7%). The mediating ratio of poor sleep quality was the highest in urban males. Conclusions: MPA has both direct and indirect effects on suicide behaviors. For suicide prevention, limited mobile phone use and improvement sleep quality may be practical for adolescents. Additionally, more efforts of intervention could give priority to rural girls.

Specific and cumulative effects of childhood maltreatment on nonsuicidal self-injury in Chinese adolescents: The moderating effect of sleep disturbance.

BACKGROUND: Numerous studies have examined the relationship between childhood maltreatment (CM) and nonsuicidal self-injury (NSSI). However, few studies have explored both the specific and cumulative effects of CM on NSSI. Additionally, the impact of sleep disturbance on the association between CM and NSSI remains unclear. OBJECTIVES: To comprehensively explore the effects of CM on NSSI, and to determine whether these effects are moderated by sleep disturbance. PARTICIPANTS AND SETTING: A retrospective study was conducted in April 2021 among a representative sample of 21,340 students aged 11-20 years in China. METHODS: All participants completed questionnaires assessing CM, sleep disturbance, and NSSI. Adjusted multivariate logistic regression models were utilized to evaluate the associations between CM and NSSI, as well as the impact of sleep disturbance. RESULTS: The findings revealed that 13.0 % of adolescents reported occasional NSSI, while 25.2 % reported repetitive NSSI. Except for sexual abuse, all subtypes of CM were significantly associated with increased odds of both occasional and repetitive NSSI. A significant dose-response relationship was observed between cumulative CM and repetitive NSSI. Stratification analyses by sleep disturbance indicated that adolescents reporting sleep disturbance had a higher risk of developing repetitive NSSI, irrespective of the type of CM experienced. Furthermore, a dose-response relationship was identified between cumulative CM and repetitive NSSI among adolescents reporting sleep disturbance. CONCLUSION: This study demonstrated that CM increases the risk of NSSI among Chinese adolescents, and sleep disturbance plays a moderating role. Interventions targeting sleep disturbance may hold significance in reducing NSSI.

Evolving from Didactic to Dialogic: How to Improve Faculty Development and Support Faculty Developers by Using Action Research.

Problem: Since competency-based medical education has gained widespread acceptance to guide curricular reforms, faculty development has been regarded as an indispensable element to make these programs successful. Faculty developers have striven to design and deliver myriad of programs or workshops to better prepare faculty members for fulfilling their teaching roles. However, how faculty developers can improve workshop delivery by researching their teaching practices remains underexplored. Intervention: Action research aims to understand real world practices and advocates for formulation of doable plans through cycles of investigations, and ultimately contributes to claims of knowledge and a progression toward the goal of practice improvement. This methodology aligns with the aim of this study to understand how I could improve a faculty development workshop by researching my teaching practices. Context: In 2016, we conducted four cycles of action research in the context of mini-Clinical Evaluation Exercise (mini-CEX) workshops within a faculty development program aiming for developing teaching and assessment competence in faculty members. We collected multiple sources of qualitative data for thematic analysis, including my reflective journal, field notes taken by a researcher-observer, and post-workshop written reflection and feedback in portfolio from fourteen workshop attendees aiming to develop faculty teaching and assessment competence. Impact: By doing action research, I scrutinized each step as an opportunity for change, enacted adaptive practice and reflection on my teaching practices, and formulated action plans to transform a workshop design through each cycle. In so doing, my workshop evolved from didactic to dialogic with continuous improvement on enhanced engagement, focused discussion and participant empowerment through a collaborative inquiry into feedback practice. Moreover, these processes of action research also supported my growth as a faculty developer. Lessons Learned: The systematic approach of action research serves as a vehicle to enable faculty developers to investigate individual teaching practices as a self-reflective inquiry, to examine, rectify, and transform processes of program delivery, and ultimately introduce themselves as agents for change and improvement.

Novel adaptive loss weighted transfer network for partial domain fault diagnosis.

Mechanical fault transfer diagnosis has been confirmed as a feasible approach for tackling intelligent diagnosis with incomplete fault information and scarce labeled data on the basis of big data through the transfer of diagnostic knowledge from one or more conditions to any other condition. However, existing research has developed a hypothesis, i.e., the target domain shares an identical label space with the source domain, making it unfeasible to address the practical issue that the target domain label space is a subset of the source domain label space, resulting in low transfer diagnosis accuracy. To address this issue, a novel unsupervised intelligent diagnosis approach named double classifiers-dependent transfer diagnosis network is developed. In this approach, the label distribution weights are generated through the probability output of the classifier of source domain label space to target domain samples, by which small weights are assigned to irrelevant source samples to avoid negative transfer in the global-local maximum mean discrepancies (GL-MMD). In addition, classifiers of the source domain label space and the shared label space are built separately to improve the reliability of label distribution weights and GL-MMD. By training the network in the shared label space, diagnostic knowledge in partial domain issues is effectively transferred. Two cases are implemented to verify the effectiveness of the developed approach. Compared with other transfer diagnosis approaches, the developed approach achieved better diagnostic performance.

A Backing-Layer-Shared Miniature Dual-Frequency Ultrasound Probe for Intravascular Ultrasound Imaging: In Vitro and Ex Vivo Validations.

Intravascular ultrasound (IVUS) imaging has been extensively utilized to visualize atherosclerotic coronary artery diseases and to guide coronary interventions. To receive ultrasound signals within the vessel wall safely and effectively, miniaturized ultrasound transducers that meet the strict size constraints and have a simple manufacturing procedure are highly demanded. In this work, the first known IVUS probe that employs a backing-layer-shared dual-frequency structure and a single coaxial cable is introduced, featuring a small thickness and easy interconnection procedure. The dual-frequency transducer is designed to have center frequencies of 30 MHz and 80 MHz, and both have an aperture size of 0.5 mm × 0.5 mm. The total thickness of the dual-frequency transducer is less than 700 µm. In vitro phantom imaging and ex vivo porcine coronary artery imaging experiments are conducted. The low-frequency transducer achieves spatial resolutions of 40 µm axially and 321 µm laterally, while the high-frequency transducer exhibits axial and lateral resolutions of 17 µm and 247 µm, respectively. A bandpass filter is utilized to separate the ultrasound images. Combining in vitro phantom imaging analysis with ex vivo imaging validation, a comprehensive demonstration of the promising application of the proposed miniature ultrasound probe is established.

Flexible Ultrasonic Transducers for Wearable Biomedical Applications: A Review on Advanced Materials, Structural Designs, and Future Prospects.

Due to the rapid developments in materials science and fabrication techniques, wearable devices have recently received increased attention for biomedical applications, particularly in medical ultrasound imaging, sensing, and therapy. Ultrasound is ubiquitous in biomedical applications because of its non-invasive nature, nonionic radiating, high precision, and real-time capabilities. While conventional ultrasound transducers are rigid and bulky, flexible transducers can be conformed to curved body areas for continuous sensing without restricting tissue movement or transducer shifting. This article comprehensively reviews the application of flexible ultrasound transducers in the field of biomedical imaging, sensing, and therapy. First, we review the background of flexible ultrasound transducers. Following that, we discuss advanced materials and fabrication techniques for flexible ultrasound transducers and their enabling technology status. Lastly, we highlight and summarize some promising preliminary data with recent applications of flexible ultrasound transducers in biomedical imaging, sensing, and therapy. We also provide technical barriers, challenges, and future perspectives for further research and development.