Intraoral Ultrasound Imaging Using a Rotational Transducer with Periodontal Feature Identification by Machine Learning.

Innovative intraoral ultrasound devices with smart artificial intelligence-based identification for dento-anatomy could provide crucial information for oral health diagnosis and treatment and shed light on real-time detection of developmental dentistry. However, the grand challenge is that the current ultrasound technologies are meant for external use due to their bulkiness and low frequency. We report a compact versatile ultrasound intraoral device that consists of a rotational probe head robustly pivoted around a hand-held and portable handle for real-time imaging of intraoral anatomy using high-frequency ultrasonography (up to 25 MHz). The intraoral ultrasound device that could be adjusted for various orientations of the imaging planes by rotating the head provides real-time, high-resolution ultrasonograms of intraoral structures, including dento-periodontium of most tooth types and maxillary palate. Machine learning-based algorithms are integrated to automate the identification of important structures, including alveolar bone and cementum-enamel junction. The intraoral ultrasound device smartened with artificial intelligence could innovate oral health diagnosis and treatment plans toward precision health and patient care.

Evaluation of Hemodynamic Alterations after Flow Diverter Placement using the AneurysmFlowTM tool.

Background: AneurysmFlow (Phillips Healthcare) is the flow measurement tool, utilizing an optical flow-based algorithm from DSA, lacks sufficient published studies. This study aimed to assess the significance of flow velocity changes and the Mean Aneurysm Flow Amplitude (MAFA) ratio in evaluating outcomes following flow-diverting treatments. Methods: Between June 2021 and October 2022, 41 patients with 42 aneurysms underwent FDS treatment with AneurysmFlow measu-rement at the Bach Mai Radiology Center. Results: The tool achieved a 90.5% success rate in 38 out of 42 patients. Most aneurysms (89.5%) were small to medium-sized (<10 mm), and a decrease in flow velocity post-stent deployment was ob-served in 78.9% of cases. Conversely, 21.1% showed increased flow, mainly in aneurysms smaller than 5 mm. No significant association was found between flow changes or MAFA ratio and aneurysm size characteristics. Twenty-two patients (59.5%) underwent re-examination at 6 months, revealing no correlation in MAFA ratio between completely and incompletely occluded aneurysms. Conclusions: Our current investigation, primarily centered on small and medium-sized aneurysms, did not uncover any link between quantitative flow changes assessed using the AneurysmFlow software and the occlusion status of aneurysms at the 6-month follow-up post-flow diverter treatment. Larger case series with extended follow-up imaging are necessary to further explore these findings.

Ultrasonic mapping of midpalatal suture - An ex-vivo study.

OBJECTIVE: Rapid maxillary expansion is a common orthodontic procedure to correct maxillary constriction. Assessing the midpalatal suture (MPS) expansion plays a crucial role in treatment planning to determine its effectiveness. The objectives of this preliminary investigation are to demonstrate a proof of concept that the palatal bone underlying the rugae can be clearly imaged by ultrasound (US) and the reconstructed axial view of the US image accurately maps the MPS patency. METHODS: An ex-vivo US scanning was conducted on the upper jawbones of two piglet's carcasses before and after the creation of bone defects, which simulated the suture opening. The planar images were processed to enhance bone intensity distribution before being orderly stacked to fuse into a volume. Graph-cut segmentation was applied to delineate the palatal bone to generate a bone volume. The accuracy of the reconstructed bone volume and the suture opening was validated by the micro-computed tomography (µCT) data used as the ground truth and compared with cone beam computed tomography (CBCT) data as the clinical standard. Also included in the comparison is the rugae thickness. Correlation and Bland-Altman plots were used to test the agreement between the two methods: US versus µCT/CBCT. RESULTS: The reconstruction of the US palatal bone volumes was accurate based on surface topography comparison with a mean error of 0.19 mm for pre-defect and 0.15 mm and 0.09 mm for post-defect models of the two samples, respectively when compared with µCT volumes. A strong correlation (R2 ≥ 0.99) in measuring MPS expansion was found between US and µCT/CBCT with MADs of less than 0.05 mm, 0.11 mm and 0.23 mm for US, µCT and CBCT, respectively. CONCLUSIONS: It was possible to axially image the MPS opening and rugae thickness accurately using high-frequency ultrasound. CLINICAL SIGNIFICANCE: This study introduces an ionizing radiation-free, low-cost, and portable technique to accurately image a difficult part of oral cavity anatomy. The advantages of conceivable visualization could promise a successful clinical examination of MPS to support the predictable treatment outcome of maxillary transverse deficiency.

Milan system for reporting salivary gland cytology in diagnosis and surgery of parotid gland lesions.

INTRODUCTION: A cytology report is always a challenge for both head and neck surgeons and cytopathologists to diagnose and manage parotid gland (PG) diseases, because of the various similar features between the lesions. OBJECTIVES: The present study was conducted to assess our practice using the Milan System for Reporting Salivary Cytopathology (MSRSGC) and to evaluate the risk of malignancy (ROM) in different categories. PATIENTS AND METHODS: The patients with parotid gland lesions were diagnosed by clinical examination, ultrasound, and FNAC under ultrasound guidance at our hospital from 1 May 2019 to 30 April 2021. The FNAC results were divided into six categories according to the Milan system. We calculated the ROM for each category of the Milan system based on histopathological follow-up. RESULTS: This study included 204 patients. There were 115 men (56 %) aged 46-60 years. Pathology results were 33 cases for malignant and 182 cases for benign. The rate of malignancy for each category according to the MSRSGC were 23.1 % (non-neoplastic), 20 % (atypical), 50 % (neoplastic), 1 % (benign), 10.3 % (salivary neoplasm of uncertain neoplastic potential), 84.6 % (suspicious for malignancy), and 100 % (malignant) categories. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of FNAC with application of Milan system were respectively 90.9 %, 98.2 %, 90.9 %, 98.9 % and 97 %. CONCLUSION: When the Milan system was applied, FNAC had a high efficacy, suggesting that MSRSGC can improve the communication between the cytopathologist and the surgeon. This system can allow the surgeon to decide the extent of the surgery.

Measuring the alveolar bone level in adolescents: A comparison between ultrasound and cone beam computed tomography.

BACKGROUND: Cone beam computed tomography (CBCT) is an imaging modality, which is used routinely in orthodontic diagnosis and treatment planning but delivers much higher radiation than conventional dental radiographs. Ultrasound is a noninvasive imaging method that creates an image without ionizing radiation. AIM: To investigate the reliability of ultrasound and the agreement between ultrasound and CBCT in measuring the alveolar bone level (ABL) on the buccal/labial side of the incisors in adolescent orthodontic patients. DESIGN: One hundred and eighteen incisors from 30 orthodontic adolescent patients were scanned by CBCT with 0.3-mm voxel size and ultrasound at 20 MHz frequency. The ABL, distance from the cementoenamel junction (CEJ) to the alveolar bone crest (ABC), was measured twice to evaluate the agreement between ultrasound and CBCT. In addition, the intra- and inter-rater reliabilities in measuring the ABL by four raters were compared. RESULTS: The mean difference (MD) in the ABL between ultrasound and CBCT was -0.07 mm with 95% limit of agreement (LoA) from -0.47 to 0.32 mm for all teeth. For each jaw, the MDs between the ultrasound and CBCT were -0.18 mm (for mandible with 95% LoA from -0.53 to 0.18 mm) and 0.03 mm (for maxilla with 95% LoA from -0.28 to 0.35 mm). In comparison, ultrasound had higher intra-rater (ICC = 0.83-0.90) and inter-rater reliabilities (ICC = 0.97) in ABL measurement than CBCT (ICC = 0.56-0.78 for intra-rater and ICC = 0.69 for inter-rater reliabilities). CONCLUSION: CBCT parameters used in orthodontic diagnosis and treatment planning in adolescents may not be a reliable tool to assess the ABL for the mandibular incisors. On the contrary, ultrasound imaging, an ionizing radiation-free, inexpensive, and portable diagnostic tool, has potential to be a reliable diagnostic tool in assessing the ABL in adolescent patients.

Estimating Crestal Thickness of Alveolar Bones on Intra-oral Ultrasonograms.

OBJECTIVE: Alveolar crestal bone thickness and level provide important diagnostic and prognostic information for orthodontic treatment, periodontal disease management and dental implants. Ionizing radiation-free ultrasound has emerged as a promising clinical tool in imaging oral tissues. However, the ultrasound image is distorted when the wave speed of the tissue of interest is different from the mapping speed of the scanner and, therefore, the subsequent dimension measurements are not accurate. This study was aimed at deriving a correction factor that can be applied to the measurements to correct for discrepancy caused by speed variation. METHODS: The factor is a function of the speed ratio and the acute angle that the segment of interest makes with the beam axis perpendicular to the transducer. The phantom and cadaver experiments were designed to validate the method. DISCUSSION: The comparisons agree well with absolute errors not more than 4.9%. Dimension measurements on ultrasonographs can be properly corrected by applying the correction factor without recourse to the raw signals. CONCLUSION: The correction factor has reduced the measurement discrepancy on the acquired ultrasonographs for the tissue whose speed is different from the scanner's mapping speed.

Temporomandibular joint segmentation in MRI images using deep learning.

OBJECTIVES: Temporomandibular joint (TMJ) internal derangements (ID) represent the most prevalent temporomandibular joint disorder (TMD) in the population and its diagnosis typically relies on magnetic resonance imaging (MRI). TMJ articular discs in MRIs usually suffer from low resolution and contrast, and it is difficult to identify them. In this study, we applied two convolutional neural networks (CNN) to delineate mandibular condyle, articular eminence, and TMJ disc in MRI images. METHODS: The models were trained on MRI images from 100 patients and validated on images from 40 patients using 2D slices and 3D volume as input, respectively. Data augmentation and five-fold cross-validation scheme were applied to further regularize the models. The accuracy of the models was then compared with four raters having different expertise in reading TMJ-MRI images to evaluate the performance of the models. RESULTS: Both models performed well in segmenting the three anatomical structures. A Dice coefficient of about 0.7 for the articular disc, more than 0.9 for the mandibular condyle, and Hausdorff distance of about 2mm for the articular eminence were achieved in both models. The models reached near-expert performance for the segmentation of TMJ articular disc and performed close to the expert in the segmentation of mandibular condyle and articular eminence. They also surpassed non-experts in segmenting the three anatomical structures. CONCLUSION: This study demonstrated that CNN-based segmentation models can be a reliable tool to assist clinicians identifying key anatomy on TMJ-MRIs. The approach also paves the way for automatic diagnosis of TMD. CLINICAL SIGNIFICANCE: Accurately locating the articular disc is the hardest and most crucial step in the interpretation of TMJ-MRIs and consequently in the diagnosis of TMJ-ID. Automated software that assists in locating the articular disc and its surrounding structures would improve the reliability of TMJ-MRI interpretation, save time and assist in reader training. It will also serve as a foundation for additional automated analysis of pathology in TMJ structures to aid in TMD diagnosis.

Comparative genomics of Nocardia seriolae reveals recent importation and subsequent widespread dissemination in mariculture farms in the South Central Coast region, Vietnam.

Between 2010 and 2015, nocardiosis outbreaks caused by Nocardia seriolae affected many permit farms throughout Vietnam, causing mass fish mortalities. To understand the biology, origin and epidemiology of these outbreaks, 20 N. seriolae strains collected from farms in four provinces in the South Central Coast region of Vietnam, along with two Taiwanese strains, were analysed using genetics and genomics. PFGE identified a single cluster amongst all Vietnamese strains that was distinct from the Taiwanese strains. Like the PFGE findings, phylogenomic and SNP genotyping analyses revealed that all Vietnamese N. seriolae strains belonged to a single, unique clade. Strains fell into two subclades that differed by 103 SNPs, with almost no diversity within clades (0-5 SNPs). There was no association between geographical origin and subclade placement, suggesting frequent N. seriolae transmission between Vietnamese mariculture facilities during the outbreaks. The Vietnamese strains shared a common ancestor with strains from Japan and China, with the closest strain, UTF1 from Japan, differing by just 220 SNPs from the Vietnamese ancestral node. Draft Vietnamese genomes range from 7.55 to 7.96 Mbp in size, have an average G+C content of 68.2 % and encode 7 602-7958 predicted genes. Several putative virulence factors were identified, including genes associated with host cell adhesion, invasion, intracellular survival, antibiotic and toxic compound resistance, and haemolysin biosynthesis. Our findings provide important new insights into the epidemiology and pathogenicity of N. seriolae and will aid future vaccine development and disease management strategies, with the ultimate goal of nocardiosis-free aquaculture.

Ethical and Policy Implications of Financial Burden in Family Caregivers.

Palliative care nurses are key members of the health care team and provide support to patients and their families navigating chronic and life-limiting illness. Financial burden is an issue inherent to chronic illness, yet has not been fully addressed in family caregivers. The purpose of this article is to (1) provide a case study of a family caregiver navigating chronic illness with her daughter and the associated financial and employment consequences and (2) review the nursing ethical, policy, and practice implications of financial burden for family caregivers. The ethical implications of financial burden in family caregivers relate to health equity and health outcomes for both the patient and family caregiver in treatment access and quality. The policy implications include state and federal policies related to caregiver compensation and support and family medical leave. Palliative care nurses play an integral role in addressing caregiver financial burden through assessment, education, referral, and policy support. Family caregivers are essential to the palliative care team, and palliative care nurses have the opportunity to lead initiatives to support the financial well-being of family caregivers in practice, research, and policy settings.

Effect of mechanical thrombectomy with vs. without intravenous thrombolysis in acute ischemic stroke.

Background: The results of mechanical thrombectomy (MT), wi-thout or with intravenous thrombolysis, were evaluated and compared in 178 patients with acute ischemic stroke (AIS) due to large vessel occlusions (LVO) at Bach Mai Hospital. Methods: A total of 178 patients with AIS due to LVO were assigned to undergo MT alone (MT-alone group) or MT preceded by intravenous alteplase (the combined group), at a dose of 0.9 mg per kilogram, administered within 4.5 hours after symptom onset (combined group). The successful recanalization rate (assessed as thrombolysis in cerebral infarction [TICI] classification of 2b-3) and the incidence of good clinical recovery outcomes (modified Rankin Scale [mRS] ≤2) after 3 months were analyzed in both groups and compared. Results: A total of 178 patients were enrolled (median age, 65 years; 55% men; median National Institutes of Health Stroke Scale [NIHSS]: 14.3). Favorable outcomes were reported in 76 patients (66.7%) in the MT-alone group and 42 patients (65.6%) in the com-bined group, with no significant between-group difference (P = 0.31 for noninferiority). However, MT alone was associated with a lower percentage of patients with successful reperfusion after MT compared with the combined group (87.7% vs. 90.6%). Mortality at 90 days was 12.2% (14 patients) in the MT-alone group and 17.2% (11 patients) in the combined group. The incidence of symptomatic intracerebral hemorrhage was not significantly different between groups (6 [5.3%] vs. 1 [1.6%]; P = 0.42). Conclusion: Among patients with AIS due to LVO in our study, MT alone was noninferior in terms of functional outcomes compared with MT preceded by the administration of intravenous alteplase within 4.5 hours after symptom onset.

The Fused Methionine Sulfoxide Reductase MsrAB Promotes Oxidative Stress Defense and Bacterial Virulence in Fusobacterium nucleatum.

Fusobacterium nucleatum, an anaerobic Gram-negative bacterium frequently found in the human oral cavity and some extra-oral sites, is implicated in several important diseases: periodontitis, adverse pregnancy outcomes, and colorectal cancer. To date, how this obligate anaerobe copes with oxidative stress and host immunity within multiple human tissues remains unknown. Here, we uncovered a critical role in this process of a multigene locus encoding a single, fused methionine sulfoxide reductase (MsrAB), a two-component signal transduction system (ModRS), and thioredoxin (Trx)- and cytochrome c (CcdA)-like proteins, which are induced when fusobacterial cells are exposed to hydrogen peroxide. Comparative transcriptome analysis revealed that the response regulator ModR regulates a large regulon that includes trx, ccdA, and many metabolic genes. Significantly, specific mutants of the msrAB locus, including msrAB, are sensitive to reactive oxygen species and defective in adherence/invasion of colorectal epithelial cells. Strikingly, the msrAB mutant is also defective in survival in macrophages, and it is severely attenuated in virulence in a mouse model of preterm birth, consistent with its failure to spread to the amniotic fluid and colonize the placenta. Clearly, the MsrAB system regulated by the two-component system ModRS represents a major oxidative stress defense pathway that protects fusobacteria against oxidative damage in immune cells and confers virulence by enabling attachment and invasion of multiple target tissues. IMPORTANCE F. nucleatum colonizes various human tissues, including oral cavity, placenta, and colon. How this obligate anaerobe withstands oxidative stress in host immune cells has not been described. We report here that F. nucleatum possesses a five-gene locus encoding a fused methionine sulfoxide reductase (MsrAB), a two-component signal transduction system (ModRS), and thioredoxin- and cytochrome c-like proteins. Regulated by ModRS, MsrAB is essential for resistance to reactive oxygen species, adherence/invasion of colorectal epithelial cells, and survival in macrophage. Unable to colonize placenta and spread to amniotic fluid, the msrAB mutant failed to induce preterm birth in a murine model.

Localization of cementoenamel junction in intraoral ultrasonographs with machine learning.

OBJECTIVE: Our goal was to automatically identify the cementoenamel junction (CEJ) location in ultrasound images using deep convolution neural networks (CNNs). METHODS: Three CNNs were evaluated using 1400 images and data augmentation. The training and validation were performed by an experienced nonclinical rater with 1000 and 200 images, respectively. Four clinical raters with different levels of experience with ultrasound tested the networks using the other 200 images. In addition to the comparison of the best approach with each rater, we also employed the simultaneous truth and performance level estimation (STAPLE) algorithm to estimate a ground truth based on all labelings by four clinical raters. The final CEJ location estimate was obtained by taking the first moment of the posterior probability computed using the STAPLE algorithm. The study also computed the machine learning-measured CEJ-alveolar bone crest distance. RESULTS: Quantitative evaluations of the 200 images showed that the comparison of the best approach with the STAPLE-estimate yielded a mean difference (MD) of 0.26 mm, which is close to the comparison with the most experienced nonclinical rater (MD=0.25 mm) but far better than the comparison with clinical raters (MD=0.27-0.33 mm). The machine learning-measured CEJ-alveolar bone crest distances correlated strongly (R = 0.933, p < 0.001) with the manual clinical labeling and the measurements were in good agreement with the 95% Bland-Altman's lines of agreement between -0.68 and 0.57 mm. CONCLUSIONS: The study demonstrated the feasible use of machine learning methodology to localize CEJ in ultrasound images with clinically acceptable accuracy and reliability. Likelihood-weighted ground truth by combining multiple labels by the clinical experts compared favorably with the predictions by the best deep CNN approach. CLINICAL SIGNIFICANCE: Identification of CEJ and its distance from the alveolar bone crest play an important role in the evaluation of periodontal status. Machine learning algorithms can learn from complex features in ultrasound images and have potential to provide a reliable and accurate identification in subsecond. This will greatly assist dental practitioners to provide better point-of-care to patients and enhance the throughput of dental care.

Three-dimensional periodontal investigations using a prototype handheld ultrasound scanner with spatial positioning reading sensor.

AIM: To demonstrate the feasibility of the 3D ultrasound periodontal tissue reconstruction of the lateral area of a porcine mandible using standard 2D ultrasound equipment and spatial positioning reading sensors. MATERIAL AND METHOD: Periodontal 3D reconstructions were performed using a free-hand prototype based on a 2D US scanner and a spatial positioning reading sensor. For automated data processing, deep learning algorithms were implemented and trained using semi-automatically seg-mented images by highly specialized imaging professionals. RESULTS: US probe movement analysis showed that non-parallel 2D frames were acquired during the scanning procedure. Comparing 3 different 3D periodontal reconstructions of the same porcine mandible, the accuracy ranged between 0.179 mm and 0.235 mm. CONCLUSION: The present study demonstrated the diagnostic potential of 3D reconstruction using a free-hand 2D US scanner with spatial positioning readings. The use of auto-mated data processing with deep learning algorithms makes the process practical in the clinical environment for assessment of periodontal soft tissues.

Rural-urban differences in preferences for influenza vaccination among women of childbearing age: implications for local vaccination service implementation in Vietnam.

OBJECTIVES: Pregnant women and new mothers are among the most vulnerable to seasonal influenza; however, little is known about their preferences for flu vaccination. We examined the rural-urban differences in uptake, demand and willingness to pay (WTP) for influenza vaccination among women of childbearing age, to assess the feasibility of implementing locally produced vaccines in Vietnam. METHODS: A cross-sectional study was performed in both urban and rural areas of Hanoi in 2018. Socio-demographic characteristics, history of vaccination, demand and WTP for influenza vaccines were obtained. A multivariate logistic regression model was employed to identify the associated factors. RESULTS: Of 750 participants, 29.9% had had flu shots in the current or previous flu season and 64.3% indicated demand for this vaccine. The median of the maximum amount of WTP for influenza vaccination services was US$ 8.5 (IQR: 8.5-17.0). Women living in rural areas had a significantly lower uptake and higher demand, and were willing to pay less than women in urban locations (21.1% vs. 36.6%; 69% vs. 60.2%; and US $8.5 vs. US $11.7, respectively). For urban participants, factors associated with higher demand and WTP for flu shots included having ANC in health facilities and having been vaccinated against influenza in the past; for rural women, these factors were having suffered from influenza and hearing about it. CONCLUSIONS: This study informs the feasibility of implementing locally produced influenza vaccines in Vietnam. Educational programs, along with counselling services and government subsidies, should be implemented to improve the coverage, demand and WTP for the vaccine.

OBJECTIFS: Les femmes enceintes et les nouvelles mères sont parmi les plus vulnérables à la grippe saisonnière; cependant, on en sait peu sur leurs préférences pour la vaccination contre la grippe. Nous avons examiné les différences entre les zones rurales et urbaines dans l'adoption, la demande et la volonté de payer pour la vaccination antigrippale chez les femmes en âge de procréer, afin d'évaluer la faisabilité de la mise en œuvre de vaccins produits localement au Vietnam. MÉTHODES: Une étude transversale a été réalisée dans les zones urbaines et rurales de Hanoi en 2018. Les caractéristiques sociodémographiques, les antécédents de vaccination, la demande et la volonté de payer pour les vaccins antigrippaux ont été obtenus. Un modèle de régression logistique multivariée a été utilisé pour identifier les facteurs associés. RÉSULTATS: Sur 750 participantes, 29,9% s'étaient fait vacciner contre la grippe au cours de la saison grippale actuelle ou précédente, 64,3% ont indiqué une demande pour ce vaccin. La médiane du montant maximal de la volonté de payer pour les services de vaccination contre la grippe était de 8,5 USD (IQR: 8,5 à 17,0). Les femmes vivant dans les zones rurales avaient une adoption nettement plus faible, une demande plus élevée et étaient prêtes à payer moins que les femmes des zones urbaines (21,1% contre 36,6%; 69% contre 60,2%; et 8,5 USD contre 11,7 USD, respectivement). Pour les participantes urbaines, les facteurs associés à une demande plus élevée et à la volonté de payer pour les vaccins contre la grippe comprenaient le fait d'avoir des soins prénatals dans les établissements de santé et d'avoir été vaccinés contre la grippe dans le passé; pour les femmes rurales, ces facteurs comprenaient, avoir souffert de la grippe et en avoir entendu parler. CONCLUSIONS: Cette étude informe sur la faisabilité de la mise en œuvre de vaccins antigrippaux produits localement au Vietnam. Des programmes éducatifs, ainsi que des services de conseil et des subventions gouvernementales devraient être mis en œuvre pour améliorer la couverture, la demande et la volonté de payer pour le vaccin.

Attitudes about and practices for skin cancer prevention among patients with dermatological issues in Hanoi, Vietnam: a cross-sectional study.

BACKGROUND: Raising awareness and educating people regarding practices for skin cancer or melanoma prevention are critical in the context of the adversely increasing effects of global climate change. This study aimed to explore the knowledge, attitudes, and practices regarding skin cancer prevention and to determine the associated factors to knowledge, attitudes, and practices among dermatological patients in Vietnam. METHODS: This cross-sectional study included 590 dermatological patients between 18 and 82 years of age, who received an examination or treatment from the National Hospital of Dermatology in Hanoi, Vietnam, from September to December 2018. The respondents' attitudes on skin cancer and cancer prevention were assessed via face-to-face interviews with a structured questionnaire conducted by trained interviewers. RESULTS: Of the 590 respondents, the majority of people had correct responses to the question regarding skin cancer knowledge. Among the total participants, 39.8% thought that they were at risk of skin cancer, and 13.8% believed their occupation increased their skin cancer risk. The majority of respondents used hats (94.9%) and sunscreen skin coats (89.5%) and went into the shade (86.3%) when exposed to the sun. Women were less likely to be aware of their skin cancer risk but were more likely to practice prevention behaviors. CONCLUSION: Our results show that dermatological patients have acceptable knowledge towards skin cancer prevention, but still need to change their behavior to prevent the risk of skin cancer. This study highlights the importance of education to raise awareness regarding skin cancer in order to promote practice prevention strategies for skin cancer in Vietnam.

Allelopathic Potential of Rice and Identification of Published Allelochemicals by Cloud-Based Metabolomics Platform.

The methanol extracts of nine popular cultivated Vietnamese rice cultivars (Oryza sativa L.cv. OM 2395, 5451, 6976, 380, 5930, 4498, 3536, N406, and 7347) were used to explore their allelopathic potential on barnyardgrass (Echinochola crus-galli L.). At 0.1 g mL-1, OM 5930, OM 4498, and OM 6976 correlatively possessed greatest phytotoxicity on barnyardgrass shoot (98.77%, 90.75%, and 87.17%) and root (99.39%, 92.83%, and 86.56%) growth. The following study aimed to detect previously-known allelochemicals in those rice using XCMS online cloud-based metabolomics platform. Twenty allelochemicals were semi-quantified and seven of them were detected predominantly and five was putatively confirmed in OM 5930 (mg/ 100g fresh rice) as salicylic acid (5.0076), vanillic acid (0.1246), p-coumaric acid (0.1590), 2,4-dimethoxybenzoic acid (0.1045), and cinnamic acid (3.3230). These compounds were active at concentrations greater than 0.5 mM and the average EC50 were 1.24 mM. The results indicated that OM 5930 may use as promising candidates in weed biological control for rice production.

Polyacrylamide/Alginate double-network tough hydrogels for intraoral ultrasound imaging.

HYPOTHESIS: Intraoral ultrasound is a safer and economical approach to image dento-periodontal tissues and diagnose periodontal diseases compared with X-ray. A gel pad is often used as a couplant between the transducer and oral tissue to delay the ultrasound signals for better identification. However, the current commercial couplant, such as Aquaflex gel pad (AF), face many challenges, including low stability in water, poor mechanical properties, low coefficient of friction, and potential cytotoxicity issues. Polyacrylamide/sodium alginate (PAM/Alginate) double-network (DN) tough hydrogel could address these issues as the potential couplant for intraoral ultrasound imaging. EXPERIMENTS: Different critical properties required for intraoral ultrasound imaging, including stability in water, mechanical properties, frictional properties, ultrasound properties and biocompatibility of PAM/Alginate DN tough hydrogels were evaluated and compared with those of AF. FINDINGS: The PAM/Alginate DN hydrogel not only possesses better stability in water as well as improved mechanical properties and higher coefficients of friction than AF but also can provide similar ultrasound image quality as AF does. Moreover, the PAM/Alginate DN hydrogel shows lower cytotoxicity to both cancer (Hela) and fibroblast cells (MRC-5). With all these significant features, such tough hydrogels serve as a proof-of-concept ultrasound couplant with great potential in intraoral ultrasound imaging.