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1.
Nature ; 613(7943): 345-354, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36599983

RESUMO

Understanding how a subset of expressed genes dictates cellular phenotype is a considerable challenge owing to the large numbers of molecules involved, their combinatorics and the plethora of cellular behaviours that they determine1,2. Here we reduced this complexity by focusing on cellular organization-a key readout and driver of cell behaviour3,4-at the level of major cellular structures that represent distinct organelles and functional machines, and generated the WTC-11 hiPSC Single-Cell Image Dataset v1, which contains more than 200,000 live cells in 3D, spanning 25 key cellular structures. The scale and quality of this dataset permitted the creation of a generalizable analysis framework to convert raw image data of cells and their structures into dimensionally reduced, quantitative measurements that can be interpreted by humans, and to facilitate data exploration. This framework embraces the vast cell-to-cell variability that is observed within a normal population, facilitates the integration of cell-by-cell structural data and allows quantitative analyses of distinct, separable aspects of organization within and across different cell populations. We found that the integrated intracellular organization of interphase cells was robust to the wide range of variation in cell shape in the population; that the average locations of some structures became polarized in cells at the edges of colonies while maintaining the 'wiring' of their interactions with other structures; and that, by contrast, changes in the location of structures during early mitotic reorganization were accompanied by changes in their wiring.


Assuntos
Células-Tronco Pluripotentes Induzidas , Espaço Intracelular , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Análise de Célula Única , Conjuntos de Dados como Assunto , Interfase , Forma Celular , Mitose , Polaridade Celular , Sobrevivência Celular
2.
Arch Microbiol ; 206(3): 97, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349544

RESUMO

Cordyceps militaris is a well-known medicinal mushroom in Asian countries. This edible fungus has been widely exploited for traditional medicine and functional food production. C. militaris is a heterothallic fungus that requires both the mating-type loci, MAT1-1 and MAT1-2, for fruiting body formation. However, recent studies also indicated two groups of C. militaris, including monokaryotic strains carrying only MAT1-1 in their genomes and heterokaryotic strains harboring both MAT1-1 and MAT1-2. These strain groups are able to produce fruiting bodies under suitable cultivating conditions. In previous work, we showed that monokaryotic strains are more stable than heterokaryotic strains in fruiting body formation through successive culturing generations. In this study, we report a high cordycepin-producing monokaryotic C. militaris strain (HL8) collected in Vietnam. This strain could form normal fruiting bodies with high biological efficiency and contain a cordycepin content of 14.43 mg/g lyophilized fruiting body biomass. The ethanol extraction of the HL8 fruiting bodies resulted in a crude extract with a cordycepin content of 69.15 mg/g. Assays of cytotoxic activity on six human cancer cell lines showed that the extract inhibited the growth of all these cell lines with the IC50 values of 6.41-11.51 µg/mL. Notably, the extract significantly reduced cell proliferation and promoted apoptosis of breast cancer cells. Furthermore, the extract also exhibited strong antifungal activity against Malassezia skin yeasts and the citrus postharvest pathogen Penicillium digitatum. Our work provides a promising monokaryotic C. militaris strain as a bioresource for medicine, cosmetics, and fruit preservation.


Assuntos
Antineoplásicos , Cordyceps , Neoplasias , Penicillium , Humanos , Penicillium/genética , Carpóforos
4.
J Nat Prod ; 83(4): 1201-1206, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32208696

RESUMO

Six new chiro-inositol derivatives (1-6) were isolated from the leaves of Chisocheton paniculatus collected in Vietnam. Their chemical structures were elucidated by 1D and 2D NMR and HRESIMS analyses. All isolated compounds were evaluated for their inhibitory activity against lipopolysaccharide-induced nitric oxide (NO) production in the RAW 264.7 macrophage cell line. Compound 4 exhibited potent inhibitory activity for NO production with an IC50 value of 7.1 µM.


Assuntos
Inositol/química , Lipopolissacarídeos/farmacologia , Óxido Nítrico/biossíntese , Folhas de Planta/química , Animais , Linhagem Celular , Lipopolissacarídeos/química , Macrófagos/metabolismo , Meliaceae/química , Camundongos , Estrutura Molecular , Óxido Nítrico/química , Células RAW 264.7 , Vietnã
5.
Pediatr Neurosurg ; 53(5): 317-321, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30145587

RESUMO

BACKGROUND: Rhabdomyosarcoma originating in the mastoid is rare and may be misdiagnosed as an infectious mastoiditis due to overlapping clinical and imaging features. We aimed to identify distinguishing characteristics to facilitate earlier diagnosis and treatment. METHOD: Here we describe a case report and a systematic review of 23 reports describing previous cases of mastoid rhabdomyosarcoma. We compare these patients to a systematic review of patients with infectious mastoiditis and identify distinguishing clinical features. RESULTS: A total of 43 patients with rhabdomyosarcoma of the mastoid were identified and compared with patients with mastoiditis. Rhabdomyosarcoma patients were more likely to present with a mass (86%) or cranial nerve dysfunction (83.7%), while mastoiditis patients were more likely to have fever (72.4%), pain (48.2%), and present at a younger age (4.4 vs. 6.1 years). The average lifespan with rhabdomyosarcoma of the mastoid was 7.1 months after diagnosis, with 41.7% of patients alive at the time of report. CONCLUSIONS: Based on abstracted and aggregated information, we identified unique features observed more frequently in each of rhabdomyosarcoma and mastoiditis. These predictive features allow for the differentiation of each diagnosis and avoid the delay of proper treatment.


Assuntos
Neoplasias Ósseas/diagnóstico , Processo Mastoide/patologia , Mastoidite/diagnóstico , Mastoidite/patologia , Rabdomiossarcoma/diagnóstico , Rabdomiossarcoma/patologia , Neoplasias Ósseas/patologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Masculino , Prognóstico
6.
J Virol ; 88(18): 10327-39, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24965444

RESUMO

UNLABELLED: HIV transmission efficiency is greatly increased when viruses are transmitted at virological synapses formed between infected and uninfected cells. We have previously shown that virological synapses formed between HIV-pulsed mature dendritic cells (DCs) and uninfected T cells contain interdigitated membrane surfaces, with T cell filopodia extending toward virions sequestered deep inside invaginations formed on the DC membrane. To explore membrane structural changes relevant to HIV transmission across other types of intercellular conjugates, we used a combination of light and focused ion beam scanning electron microscopy (FIB-SEM) to determine the three-dimensional (3D) architectures of contact regions between HIV-1-infected CD4(+) T cells and either uninfected human CD4(+) T cells or human fetal astrocytes. We present evidence that in each case, membrane extensions that originate from the uninfected cells, either as membrane sheets or filopodial bridges, are present and may be involved in HIV transmission from infected to uninfected cells. We show that individual virions are distributed along the length of astrocyte filopodia, suggesting that virus transfer to the astrocytes is mediated, at least in part, by processes originating from the astrocyte itself. Mechanisms that selectively disrupt the polarization and formation of such membrane extensions could thus represent a possible target for reducing viral spread. IMPORTANCE: Our findings lead to new insights into unique aspects of HIV transmission in the brain and at T cell-T cell synapses, which are thought to be a predominant mode of rapid HIV transmission early in the infection process.


Assuntos
Membrana Celular/virologia , Infecções por HIV/virologia , HIV-1/fisiologia , Sinapses/virologia , Astrócitos/ultraestrutura , Astrócitos/virologia , Linfócitos T CD4-Positivos/ultraestrutura , Linfócitos T CD4-Positivos/virologia , Linhagem Celular , Membrana Celular/ultraestrutura , Infecções por HIV/transmissão , Humanos , Imageamento Tridimensional , Microscopia Eletrônica de Transmissão , Sinapses/ultraestrutura
7.
Bioorg Med Chem Lett ; 25(16): 3246-50, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26077495

RESUMO

A new polyoxygenated cyclohexene, (-)-3-O-debenzoylzeylenone (1), and a new megastigmane glycoside, grandionoside A (2), were isolated from the aerial parts of Uvaria grandiflora collected in Vietnam, together with ten known compounds including polyoxygenated cyclohexenes (3-6), a triterpenoid (7), an alkaloid (8), a long chain alcohol (9), hexenyl glycopyranoside (10), and saponins (11-12). Their chemical structures were elucidated by a combination of extensive NMR spectroscopy with X-ray crystallographic analysis for 1, and chemical conversion for 2. Compound 1 exhibited significant cytotoxicity against the LU-1 and SK-Mel-2 cell lines with IC50 values of 4.68 and 3.63 µM, respectively. Remarkably, the cytotoxicity of 12 against the LU-1, KB, Hep-G2, MKN-7, and SW-480 cell lines was comparable to that of ellipticine, the positive control, with IC50 values ranging from 1.24 to 1.60 µM.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Cicloexanonas/isolamento & purificação , Cicloexanonas/farmacologia , Cicloexenos/isolamento & purificação , Cicloexenos/farmacologia , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Norisoprenoides/isolamento & purificação , Norisoprenoides/farmacologia , Uvaria/química , Sequência de Carboidratos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Elipticinas/farmacologia , Glicosídeos , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Dados de Sequência Molecular , Difração de Raios X
8.
J Nat Prod ; 78(11): 2726-30, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26516994

RESUMO

Two new clerodane diterpenoids (1 and 2) and the known compound caseanigrescen D (3) were isolated from the leaves of Casearia grewiifolia by bioassay-guided fractionation. Their structures were determined by analyses of MS and 2D NMR data. The absolute configurations of 1 and 3 were established by analysis of X-ray diffraction data. Compounds 1-3 were evaluated for their cytotoxicity against four cancer cell lines, KB (mouth epidermal carcinoma cells), HepG-2 (human liver hepatocellular carcinoma cells), LU-1 (human lung adenocarcinoma cells), and MCF-7 (human breast cancer cells). Caseagrewifolin B (2) had inhibitory activity against KB and HepG-2 cell lines with IC50 values of 6.2 to 7.0 µM, respectively. When tested against the normal cells (NIH/3T3), caseagrewifolin B (2) exhibited a significant selective inhibition against cancer cells in comparison with the normal cells. Caseanigrescen D (3) was cytotoxic against four cancer cell lines; however it had no selective inhibition compared with normal cells.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Casearia/química , Diterpenos Clerodânicos/isolamento & purificação , Diterpenos Clerodânicos/farmacologia , Plantas Medicinais/química , Antineoplásicos Fitogênicos/química , Diterpenos Clerodânicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células Hep G2 , Humanos , Células KB , Estrutura Molecular , Folhas de Planta/química , Vietnã
9.
J Int Soc Prev Community Dent ; 14(1): 78-87, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559638

RESUMO

Retrusive upper lips, retroclined upper incisors, a shorter midface, and a larger maxillary-mandibular difference are the characteristics of borderline Class III malocclusion. Individuals with borderline Class III malocclusion frequently exhibit certain morphologic, dental, and skeletal traits, which should aid in the diagnosis of the condition. To report the case of a 22-year-old Vietnamese woman who complained of having tense front teeth and lacking confidence when smiling. Medical history did not find anything strange, there was root canal treatment of the first premolar on the left of the upper jaw, asymmetrical concave chin, and right deviation. Orthodontic camouflage treatment using anterior bite turbos in combination with early light short Class III elastics and box elastics was proposed since the patient declined to have orthognathic surgery. In just 10 months of treatment, a Class I molar and canine relationship was created, an anterior crossbite was corrected via mandibular retraction, and severe skeletal malocclusions were successfully treated without orthognathic surgery. Smiling currently showcases the patient's maxillary incisors more prominently, and her lower lip fullness has diminished, giving her a more attractive smile and a significant improvement to her facial profile.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38321897

RESUMO

AIM: Anticancer treatment is required to provide effective and safe patient medicines. This research aided in developing and applying nanoparticles (NPs) for cancer treatment. BACKGROUND: The poor solubility of paclitaxel (PTX) restricts its therapeutic efficacy because of allergic side effects caused by formulation excipients. To overcome this, PTX was coupled with artemisinin derivatives and loaded into an NP drug delivery system to enhance its effects while addressing its low solubility. OBJECTIVES: This study prepared and characterized a hybrid PLGA-lecithin NP containing dihydroartemisinin (DHA) and PTX for synergic anticancer therapy. A lyophilization study improved the stability of the NP drug formulations. METHODS: Dual PTX- and DHA-loaded PLGA- and lecithin-based NPs were prepared using a single-step solvent evaporation method. The NP suspensions were lyophilized, and the types and ratios of cryoprotectants were investigated. The physicochemical properties of NPs and lyophilized cakes (Lyo-NPs) were characterized. The stability of the Lyo-NPs was investigated at 2-8°C and room conditions. The anticancer effects of the drug combination, NP suspension, and lyophilized powder were analyzed using an in vitro cytotoxicity assay and an in vivo model. RESULTS: The optimal PTX-DHA loaded PLGA-lecithin-NP was formulated (200 nm, PDI: 0.248 ± 0.003, Zeta potential: -33.60 ± 3.39 mV). Mannitol was selected for lyophilization. Lyo-NPs improved the stability of the NPs (1 year), wherein the physicochemical properties of the NPs were maintained (RDI was close to 1.0). An in-vitro cytotoxicity assay of PTX combined with DHA showed a synergistic anticancer effect (CI <1.0). The suppressive effects of Lyo-NPs on tumor growth in vivo were dose-dependent. While the cocktail of free drugs showed high toxicity (7.5 mg PTX-15 mg DHA/kg) in-vivo, Lyo-NPs showed no statistical differences in hematological and biochemical parameters compared to the control. CONCLUSION: Dual-drug-loaded hybrid PLGA-lecithin NP is a potential system to minimize severe side effects while enhancing antitumor efficacy, in which lyophilization is a key process to increase stability.

.

11.
J Conserv Dent Endod ; 27(1): 51-56, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38389749

RESUMO

Context: Optimal restoration methods for endodontically treated teeth (ETTs) have always remained an ongoing discussion among physicians in this day and age. ETTs have a tendency to fracture when chewing, compared to initial teeth. From the perspective of biology, preserving and restoring tooth structure is critical to maintaining biomechanical, functional, and esthetic harmony. Dental bonding techniques have lessened the necessity for post-and-core restorations in ETTs with severe substance loss. A minimally invasive endodontic restoration technique called "endocrown" was initially introduced by Bindl and Mörmann in 1999. Aims: The aim of the study was to clinically evaluate all-ceramic mandibular molar endocrowns made using computer-aided design/computer-aided manufacturing (CAD/CAM) following 2 years of follow-up. Subjects and Methods: This unblinded study contains 56 patients with 56 mandibular molars, which had severe substance loss. After teeth preparation, lithium disilicate ceramic endocrowns were manufactured with the CEREC CAD/CAM system, and cementation was performed using a composite luting agent. The endocrowns were assessed using the modified United States Public Health Service criteria at baseline, 6 months, 1 year, and 2 years following placement. Patient satisfaction was evaluated using a questionnaire. Statistical Analysis Used: This study used descriptive statistics, including mean, standard deviation, and 95% confidence intervals. Data were processed using STATA version 14.0 (StataCorp LLC, USA). Results: Two endocrowns (3.6%) failed throughout the period of observation. The high clinical rating criteria (96.4%, count of 54) and the increased satisfaction percentage (94.6%, count of 53) remained practically stable during the follow-up assessments at 6 months and after 1-2 years. Conclusions: Endocrown offers a less invasive treatment option that may be a better method for endodontically treated mandibular molars. With contemporary CAD/CAM technology and new materials, time in the chair and esthetics optimally improved, bringing satisfaction to the patient.

12.
Cureus ; 16(4): e59337, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38817523

RESUMO

INTRODUCTION: The mandibular foramen (MnF) and the mental foramen (MF) are essential anatomical landmarks that should be considered before any surgical procedures in the mandible. This study aimed to investigate the characteristics of the MnF and MF in relation to adjacent anatomical structures, as well as age and gender differences, using cone beam computed tomography (CBCT) projections. METHODS: The study was conducted from August 2023 to January 2024 at the Can Tho University of Medicine and Pharmacy Hospital, Vietnam. In this retrospective study, 50 CBCT images of Vietnamese patients were randomly taken for various clinical purposes. Furthermore, relevant data, such as gender and age groups, were selected to evaluate the correlations, along with specific inclusion criteria. Patients within the age range of 18-69 with a symmetrical mandible were included. RESULTS: The distance of the MnF-MN was 29.6±5.0 mm (right) and 30.1±4.6 mm (left) in males and 25.0±4.2 mm (right) and 26.3±5.0 mm (left) in females. The distance of the MnF-posterior border of the ramus (P) was 16.2±3.6 mm (right) and 15.0±2.3 mm (left) in males. For females, it was 17.1±2.9 mm (right) and 13.8±1.7 mm (left). The distance of the MF-body mandible (MB) was 15.4±2.4 mm (right) and 15.6±2.0 mm (left) in males and 14.0±2.1 mm (right) and 14.3±1.6 mm (left) in females. The distance of the MF-mandibular midline (MM) was 27.0±2.6 mm (right) and 27.0±2.9 mm (left) in males and 25.3±2.0 mm (right) and 25.1±2.2 mm (left) in females. These distances showed statistically significant differences depending on gender (P<0.05). CONCLUSION: It can be said that CBCT provides comprehensive information about the MnF and the MF for dentists in research and clinical practice.

13.
PLOS Glob Public Health ; 4(2): e0002932, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38416739

RESUMO

The working conditions for teachers in Vietnam were characterized by increased workload and pressure, burdening teachers' well-being. The study aims to investigate anxiety prevalence and identify some related factors among primary and secondary school teachers in Hanoi after the first COVID-19 outbreak in 2020. This paper analyzed data of 481 teachers working at ten primary and secondary schools in Hanoi city. Anxiety was measured using the anxiety component of the Depression, Anxiety, and Stress scale 42 items. Multivariable logistics regression was performed to examine anxiety-related factors using SPSS 20.0 at a significant level p less than 0.05. The prevalence of anxiety symptoms was 42.4% and similar between primary and secondary school teachers. More secondary teachers reported moderate to severe anxiety symptoms than primary teachers did (31.6% and 27.7%). Primary school teachers who felt discomfort with their supervisor's assessment, high responsibility for student safety, and ever thinking of leaving their current job were more likely to report anxiety symptoms (OR (95%CI) = 2.8 (1.2-6.5), 3.6 (1.0-12.8), and 2.6 (1.3-5.4), respectively). Meanwhile, the discomfort of caring for many students or problematic students, repetitive work, and disagreement with coworkers were risk factors of anxiety among secondary school teachers (OR (95%CI) = 2.6 (1.2-5.8), 3.2 (1.1-9.2), 3.4 (1.3-8.8), and 3.7 (1.1-12.6), respectively). In conclusion, the prevalence of teachers with anxiety symptoms is on the rise, caused by the characteristics of the job and professional relationships. Tailored support for teachers in different grades is necessary to improve and prevent teachers' anxiety.

14.
Nat Protoc ; 19(2): 565-594, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38087082

RESUMO

To produce abundant cell culture samples to generate large, standardized image datasets of human induced pluripotent stem (hiPS) cells, we developed an automated workflow on a Hamilton STAR liquid handler system. This was developed specifically for culturing hiPS cell lines expressing fluorescently tagged proteins, which we have used to study the principles by which cells establish and maintain robust dynamic localization of cellular structures. This protocol includes all details for the maintenance, passage and seeding of cells, as well as Matrigel coating of 6-well plastic plates and 96-well optical-grade, glass plates. We also developed an automated image-based hiPS cell colony segmentation and feature extraction pipeline to streamline the process of predicting cell count and selecting wells with consistent morphology for high-resolution three-dimensional (3D) microscopy. The imaging samples produced with this protocol have been used to study the integrated intracellular organization and cell-to-cell variability of hiPS cells to train and develop deep learning-based label-free predictions from transmitted-light microscopy images and to develop deep learning-based generative models of single-cell organization. This protocol requires some experience with robotic equipment. However, we provide details and source code to facilitate implementation by biologists less experienced with robotics. The protocol is completed in less than 10 h with minimal human interaction. Overall, automation of our cell culture procedures increased our imaging samples' standardization, reproducibility, scalability and consistency. It also reduced the need for stringent culturist training and eliminated culturist-to-culturist variability, both of which were previous pain points of our original manual pipeline workflow.


Assuntos
Células-Tronco Pluripotentes Induzidas , Humanos , Microscopia , Reprodutibilidade dos Testes , Técnicas de Cultura de Células/métodos , Automação
15.
J Orthod Sci ; 12: 58, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37881667

RESUMO

OBJECTIVE: To investigate the impact of platelet-rich plasma (PRP) on canine movement acceleration. METHODS: Randomized clinical trial split-mouth study with a double-blind design and controlled group on 31 orthodontic patients, which had been indicated bilateral maxillary first premolar extraction. Each patient recorded clinical features, analyzed lateral cephalometric film, and evaluated the acceleration on dental models at every specific interval. RESULT: The cumulative distance to the distal canines was larger for the PRP injection group than for the control group at three time points (4 weeks, 8 weeks, and 12 weeks), all of which were statistically significant. The PRP injection group's canine distal width increased from the first 4 weeks (ΔT1) to the highest in the middle 4 weeks (ΔT2 = 1.78 ± 0.11 mm/month), and then it gradually decreased in the last 4 weeks (ΔT3). The speed of the PRP-injected canine was faster than the control group by 1.51 times. CONCLUSION: PRP can accelerate the speed of canine movement in orthodontics and can be applied for severe cases, for example, impacted tooth retraction, molar protraction or retraction, and other cases.

16.
Nat Prod Res ; 37(15): 2559-2567, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35337228

RESUMO

Sixteen sesquiterpenoids including two new ones, homalolides A - B (1‒2), were firstly isolated from the methanolic extract of the rhizomes of Homalomena pendula collected in Vietnam. The structures and relative stereochemistry of new compounds were elucidated by 1D-/2D-NMR, IR, UV and HRESIMS analyses. The GCMS experiment demonstrated that homalolide A (1) is an artifact due to the methylation during methanolic extraction process. All isolates (1‒16) were tested for their inhibitory activities against lipopolysaccharide-induced nitric oxide production in the RAW 264.7 macrophage cell line. Compounds 1, 3, 6‒8, 10‒12 displayed moderate inhibitory effect on NO production with IC50 values ranging from 35.41 to 64.06 µM.


Assuntos
Araceae , Sesquiterpenos , Animais , Camundongos , Rizoma/química , Células RAW 264.7 , Macrófagos , Sesquiterpenos/química , Araceae/química , Anti-Inflamatórios/química , Óxido Nítrico , Estrutura Molecular
17.
Bioinorg Chem Appl ; 2023: 3848456, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324575

RESUMO

Lotus seedpods (LSPs) are an abundant and underutilized agricultural residue discarded from lotus seed production. In this study, ZnCl2 and FeCl3 coactivation of LSP for one-pot preparation of magnetic activated carbon (MAC) was explored for the first time. X-ray diffraction (XRD) results showed that Fe3O4, Fe0, and ZnO crystals were formed in the LSP-derived carbon matrix. Notably, transmission electron microscopy (TEM) images showed that the shapes of these components consisted of not only nanoparticles but also nanowires. Fe and Zn contents in MAC determined by atomic absorption spectroscopy (AAS) were 6.89 and 3.94 wt%, respectively. Moreover, SBET and Vtotal of MAC prepared by coactivation with ZnCl2 and FeCl3 were 1080 m2/g and 0.51 cm3/g, which were much higher than those prepared by single activation with FeCl3 (274 m2/g and 0.14 cm3/g) or ZnCl2 (369 m2/g and 0.21 cm3/g). MAC was subsequently applied as an oxidation catalyst for Fenton-like degradation of acid orange 10 (AO10). As a result, 0.20 g/L MAC could partially remove AO10 (100 ppm) with an adsorption capacity of 78.4 mg/g at pH 3.0. When 350 ppm H2O2 was further added, AO10 was decolorized rapidly, nearly complete within 30 min, and 66% of the COD was removed in 120 min. The potent catalytic performance of MAC might come from the synergistic effect of Fe0 and Fe3O4 nanocrystals in the porous carbon support. MAC also demonstrated effective stability and reusability after five consecutive cycles, when total AO10 removal at 20 min of H2O2 addition slightly decreased from 93.9 ± 0.9% to 86.3 ± 0.8% and minimal iron leaching of 1.14 to 1.19 mg/L was detected. Interestingly, the MAC catalyst with a saturation magnetization of 3.6 emu/g was easily separated from the treated mixture for the next cycle. Overall, these findings demonstrate that magnetic activated carbon prepared from ZnCl2 and FeCl3 coactivation of lotus seedpod waste can be a low-cost catalyst for rapid degradation of acid orange 10.

18.
J Orthod Sci ; 12: 35, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37351396

RESUMO

BACKGROUND AND PURPOSE: The soft-tissue layer and facial skeleton influence the harmony and equilibrium of the face. The evaluation of the patient's structural and soft-tissue features is one of the most crucial steps in preparing for the diagnosis and treatment of oral-maxillofacial orthodontics. Clinicians can intervene with the proper treatment at the proper time to achieve the best results by being aware of the traits and variations of soft tissue at various developmental stages and in various races. To obtain a consistent treatment result in terms of function and aesthetically pleasing results, patients, and forecast, the growth that may take place after the orthopedic therapy has concluded. OBJECTIVE: To examine the soft-tissue features of the oral-maxillofacial area in Vietnamese adults (aged 18-25 years) by evaluating cephalometric radiographs. MATERIALS AND METHODS: In a cross-sectional descriptive study, 85 students from Can Tho University of Medicine and Pharmacy took part. Students' lateral cephalograms were taken in compliance with the sample requirements. RESULTS: Men's lip protrusion (4.30 ± 0.71) was higher than women's (3.88 ± 0.97) (P = 0.024 <.05) and men's (-4.88 ± 0.93) chin lip groove depth was higher than women's (-4.24 ± 0.93) (P = 0.002), both with a P value of. 05. CONCLUSIONS: The study identified a statistically significant difference in the protrusion of the top lip and the depth of the cleft lip between the male and female, demonstrating that the soft-tissue features of Vietnamese students were distinct from those of other races.

19.
Dent J (Basel) ; 11(9)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37754321

RESUMO

OBJECTIVE: To assess the perceptions of faculty members from dental schools in Southeast Asian countries regarding the implementation of online learning during the COVID-19 pandemic. METHODS: A previously implemented questionnaire comprising 43 questions was utilized in this study. Lecturers from four universities in Southeast Asia were invited to participate in the study. STATISTICAL ANALYSIS: The data were analyzed using SPSS version 25.0 through several types of comparative and correlation analyses. RESULTS: There were 183 lecturers who participated in the study. The overall responses suggest that the perceived effectiveness of online learning in dentistry was centered on a neutral value. The participants faced challenges when implementing online learning during the COVID-19 pandemic, with the lack of interaction being the most challenging factor. They agreed that online learning had many advantages, specifically in time flexibility and communication. The participants had stronger perceptions relating the advantages and opportunities of online teaching, and recognized that the effectiveness of offline teaching alone was limited. CONCLUSION: The perceptions of Southeast Asian dental school faculty members were inclined toward a positive outlook on blended learning for implementation in dentistry, as a means of providing opportunities to use online learning beyond COVID-19 in the future.

20.
Dent J (Basel) ; 10(12)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36547054

RESUMO

BACKGROUND: Smile aesthetics has a vital role to play in an individual's life and one of the factors affecting the beauty of the smile is gingival color. A gingival color change or gingival hyperpigmentation causes an unesthetic smile line, especially in patients with a gummy smile, which is also known as a black gummy smile. Numerous gingival depigmentation methods have been performed successfully for ablating gingival melanin pigmented epithelium. Thus, the aim of this study is to evaluate the treatment efficacy of gingival hyperpigmentation by using a carbon dioxide (CO2) laser. METHODS: A cross-sectional descriptive study was carried out with 38 patients at a hospital in Vietnam. Ponnaiyan classification and the Hedin melanin index were used to assess the distribution and extent of gingival pigmentation in the study. Pain assessment was performed using the Visual Analog Scale (VAS) to evaluate the intensity of pain during the laser treatment. In addition, clinical evaluation (i.e., wound healing) of each treatment procedure was conducted using the three level Dummett-Gupta Oral Pigmentation Index (DOPI) assessment. RESULTS: This study showed that less pain was experienced by patients treated by CO2 laser; the rates of no pain, mild pain and moderate pain after treatment were, respectively, 21%, 76% and 2.6%; there was 100% complete epithelization after 1 week. The DOPI rates for turning from a DOPI score of 1, 2 or 3 to a DOPI score of 0 after a 12-week treatment were 87.5%, 76.9% and 24%, respectively. CONCLUSIONS: Using a CO2 laser for gingival melanin pigmentation treatment is a safe and effective procedure.

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