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1.
Development ; 151(20)2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38646855

RESUMO

Ecdysone-induced protein 93 (E93), known as the 'adult-specifier' transcription factor in insects, triggers metamorphosis in both hemimetabolous and holometabolous insects. Although E93 is conserved in ametabolous insects, its spatiotemporal expression and physiological function remain poorly understood. In this study, we first discover that, in the ametabolous firebrat Thermobia domestica, the previtellogenic ovary exhibits cyclically high E93 expression, and E93 mRNA is broadly distributed in previtellogenic ovarioles. E93 homozygous mutant females of T. domestica exhibit severe fecundity deficiency due to impaired previtellogenic development of the ovarian follicles, likely because E93 induces the expression of genes involved in ECM (extracellular matrix)-receptor interactions during previtellogenesis. Moreover, we reveal that in the hemimetabolous cockroach Blattella germanica, E93 similarly promotes previtellogenic ovarian development. In addition, E93 is also essential for vitellogenesis that is necessary to guarantee ovarian maturation and promotes the vitellogenesis-previtellogenesis switch in the fat body of adult female cockroaches. Our findings deepen the understanding of the roles of E93 in controlling reproduction in insects, and of E93 expression and functional evolution, which are proposed to have made crucial contributions to the origin of insect metamorphosis.


Assuntos
Metamorfose Biológica , Ovário , Reprodução , Animais , Feminino , Reprodução/genética , Metamorfose Biológica/genética , Ovário/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Vitelogênese/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética
2.
Clin Oral Implants Res ; 35(4): 407-418, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38287504

RESUMO

OBJECTIVES: To study bone healing of two-wall bone defects after alveolar ridge preservation using mineralized dentin matrix. MATERIALS AND METHODS: After distal roots extraction of second and fourth premolars (P2, P4) on one lateral mandible in 12 beagles, two-wall bone defects (5 × 5 × 5 mm) were surgically created distally to the remaining mesial roots of P2 and P4. A total of 24 sites were randomly allocated to three groups (implant material- time of execution): mineralized dentin matrix (MDM)-3 m (MDM + collagen membrane; 3 months), MDM-6 m (MDM particles + collagen membrane; 6 months), and C-6 m (collagen membrane only; 6 months). Clinical, radiographic, digital, and histological examinations were performed 3 and 6 months after surgery. RESULTS: The bone healing in MDM groups were better compared to Control group (volume of bone regenerated in total: 25.12 mm3 vs. 13.30 mm3, p = .046; trabecular volume/total volume: 58.84% vs. 39.18%, p = .001; new bone formation rate: 44.13% vs. 31.88%, p = .047). Vertically, the radiological bone level of bone defect in MDM-6 m group was higher than that in C-6 m group (vertical height of bone defect: 1.55 mm vs. 2.74 mm, p = .018). Horizontally, no significant differences in buccolingual bone width were found between MDM and C groups at any time or at any level below the alveolar ridge. The percentages of remaining MDM were <1% in both MDM-3 m and MDM-6 m groups. CONCLUSIONS: MDM improved bone healing of two-wall bone defects and might be considered as a socket fill material used following tooth extraction.


Assuntos
Perda do Osso Alveolar , Aumento do Rebordo Alveolar , Cães , Animais , Alvéolo Dental/cirurgia , Alvéolo Dental/patologia , Processo Alveolar/cirurgia , Processo Alveolar/patologia , Colágeno , Extração Dentária , Dentina , Perda do Osso Alveolar/prevenção & controle , Perda do Osso Alveolar/cirurgia , Perda do Osso Alveolar/patologia
3.
Clin Oral Investig ; 28(7): 375, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878120

RESUMO

OBJECTIVE: To investigate the impact of mineralized dentin matrix (MDM) on the prognosis on bone regeneration and migration of retained roots after coronectomy. MATERIALS AND METHODS: Patients were divided into three groups based on the type of bone graft after coronectomy: Group C (n = 20, collagen), Group T (n = 20, tricalcium phosphate (TCP) + collagen), and Group D (n = 20, MDM + collagen). CBCT scans, conducted immediately and 6 months after surgery, were analyzed using digital software. Primary outcomes, including changes in bone defect depth and retained root migration distance, were evaluated 6 months after surgery. RESULTS: After 6 months, both Groups D and T exhibited greater reduction of the bone defect and lesser retained root migration than Group C (p < 0.001). Group D had greater regenerated bone volume in the distal 2 mm (73 mm3 vs. 57 mm3, p = 0.011) and lesser root migration (2.18 mm vs. 2.96 mm, p < 0.001) than Group T. The proportion of completely bone embedded retained roots was also greater in Group D than in Group C (70.0% vs. 42.1%, p = 0.003). CONCLUSIONS: MDM is an appropriate graft material for improving bone defect healing and reducing retained root migration after coronectomy. CLINICAL RELEVANCE: MDM is an autogenous material prepared chairside, which can significantly improve bone healing and reduce the risk of retained root re-eruption. MDM holds promise as a routine bone substitute material after M3M coronectomy.


Assuntos
Regeneração Óssea , Fosfatos de Cálcio , Colágeno , Tomografia Computadorizada de Feixe Cônico , Dentina , Humanos , Masculino , Feminino , Fosfatos de Cálcio/uso terapêutico , Prognóstico , Pessoa de Meia-Idade , Colágeno/uso terapêutico , Regeneração Óssea/efeitos dos fármacos , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/cirurgia , Adulto , Coroa do Dente/cirurgia , Resultado do Tratamento , Transplante Ósseo/métodos , Substitutos Ósseos/uso terapêutico
4.
Clin Oral Investig ; 28(8): 439, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037593

RESUMO

OBJECTIVES: To conduct a finite element analysis of the impact of different variables on tooth sectioning efficiency and trauma to surrounding tissues when utilizing high-speed surgical handpieces and elevators. METHODS: CBCT data from the horizontally impacted third mandibular molar (M3M) of a patient were utilized to establish digital models of the M3M, adjacent M2M, and surrounding bone. To simulate tooth sectioning, a 3D finite element model was established with the following variables: remaining tooth tissue thickness (1-5 mm), tooth section fissure width (1-3 mm), elevator depth in fissure (2-6 mm), elevator position (buccal, lingual, central), elevator width (2-5 mm), and application of force (rotating, levering). Using this model, the distribution of stress on the M3M and the surrounding tissue was assessed while measuring tooth sectioning efficiency and trauma to the surrounding tissue. RESULTS: Factors associated with uniform stress at the site of sectioning included thin (≤ 3 mm) remaining tooth tissue, appropriate fissure width (~ 2 mm), a wide (≥ 4 mm) elevator, and central elevator positioning. Levering the elevator yielded greater stress on the M3M than rotating force. Greater sectioning efficiency was associated with increased stress placed on the distobuccal side of M2M. CONCLUSIONS: Tooth sectioning efficiency can be improved by adjusting the high-speed surgical handpiece and elevator. However, it is important to remain attentive to the trauma to which adjacent teeth are exposed during this process. CLINICAL SIGNIFICANCE: These results offer guidance for approaches to improving operator efficiency and reducing trauma to surrounding tissues during tooth sectioning.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Análise de Elementos Finitos , Mandíbula , Dente Serotino , Dente Impactado , Humanos , Dente Serotino/cirurgia , Dente Impactado/cirurgia , Dente Impactado/diagnóstico por imagem , Mandíbula/cirurgia , Imageamento Tridimensional , Equipamentos Odontológicos de Alta Rotação , Análise do Estresse Dentário
5.
J Environ Manage ; 354: 120254, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340668

RESUMO

Drylands, as highly vulnerable ecosystems, support environmental functions and human well-being. Nevertheless, widespread land degradation and desertification present significant global and regional environmental challenges, with limited consensus on their area and degree. This study used time-series vegetation productivity and meteorological data from 2000 to 2020 to quantify global land degradation trends and driving factors in drylands. The results show a notable restoration of land degradation in drylands worldwide, with the area of improved land exceeding the degraded area by 1.4 times, although the threat of degradation persists. India and China emerge as pioneers in effective land improvement strategies, offering valuable experiences for other regions. Combined effects, as quantitatively distinguished by our established model, dominate the degradation and improvement processes. Notably, human activities play a decisive role in influencing land degradation trends, with the potential for either exacerbation or reversal. This study provides new perspectives on environmental health and human activities from global and regional observations. Finally, our research provides scientific support for desertification control and contributes to the overall advancement of the SDGs globally.


Assuntos
Ecossistema , Desenvolvimento Sustentável , Humanos , Conservação dos Recursos Naturais/métodos , China , Atividades Humanas
6.
Odontology ; 111(4): 982-992, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36773195

RESUMO

The aim of this study is to assess the relationship between somatosensory functional changes and inferior alveolar nerve (IAN) exposure after impacted mandibular third molars (M3M) removal. We recruited 35 patients who underwent impacted M3M extraction near the IAN. The M3Ms were extracted by combined endoscopy, piezosurgery, and contra-angle high-speed turbine handpiece. All IAN canal perforations and exposed regions were recorded and measured by endoscopy after extraction and on cone-beam computed tomography (CBCT) images before extraction. The patients were followed up 1, 7, and 35 days after surgery. A standardized quantitative sensory testing (QST) battery was performed on the lower lip skin. All of 35 cases had exposed IAN on CBCT images, 5 of which had no exposed IAN under endoscopy. For the other 30 cases, the endoscopy-measured IAN length and width were shorter than the CBCT measurements (P < 0.001). The warm and mechanical detection thresholds (MDT) on the operation side were significantly higher than the contralateral side after surgery (P < 0.05). Thermal sensory limen, MDT, and cold pain threshold were strongly correlated with the exposed IAN length and MDT also with the exposed IAN width one day after surgery. In conclusion, it was found that not all exposed IAN in CBCT images were real exposure after surgery. The intraoperative exposed IAN endoscopic measurements were smaller than by CBCT and strongly correlated with some QST parameters.


Assuntos
Dente Impactado , Traumatismos do Nervo Trigêmeo , Humanos , Dente Serotino/cirurgia , Mandíbula , Endoscopia , Extração Dentária/métodos , Dente Impactado/diagnóstico por imagem , Dente Impactado/cirurgia , Nervo Mandibular/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Radiografia Panorâmica/métodos
7.
Entropy (Basel) ; 25(9)2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37761657

RESUMO

A vehicular network embodies a specialized variant of wireless network systems, characterized by its capability to facilitate inter-vehicular communication and connectivity with the encompassing infrastructure. With the rapid development of wireless communication technology, high-speed and reliable communication has become increasingly important in vehicular networks. It has been demonstrated that orthogonal time frequency space (OTFS) modulation proves effective in addressing the challenges posed by high-mobility environments, as it transforms the time-varying channels into the delay-Doppler domain. Motivated by this, in this paper, we focus on the theme of integrated sensing and communication (ISAC)-assisted OTFS receiver design, which aims to perform sensing channel estimation and communication symbol detection. Specifically, the estimation of the sensing channel is accomplished through the utilization of a deep residual denoising network (DRDN), while the communication symbol detection is performed by orthogonal approximate message passing (OAMP) processing. The numerical results demonstrate that the proposed ISAC system exhibits superior performance and robustness compared to traditional methods, with a lower complexity as well. The proposed system has great potential for future applications in wireless communication systems, especially in challenging scenarios with high mobility and interference.

8.
Mikrochim Acta ; 188(9): 311, 2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34455515

RESUMO

A simple dual-read assay for uric acid (UA) was developed based on a combined ratiometric fluorescent and colorimetric strategy using nitrogen-doped carbon dots (N-CDs). The biosensor relies on the oxidation of UA by uricase to produce H2O2, which was then converted to •OH radicals by I-, resulting in the oxidation of o-phenylenediamine (OPD) to 2,3-diaminophenazine (DAP). In the presence of UA, the colorless biosensor system changed to yellow. Furthermore, the presence of DAP quenched the fluorescence emission of the N-CDs at 427 nm based on the inner filter effect (IFE). With increasing UA concentrations, the fluorescence intensity of the biosensor at 427 nm decreased but increased at 580 nm, demonstrating the ratiometric response. A strong linearity was observed between the fluorescence intensity ratio of DAP to N-CDs (I580/I427) and the corresponding UA concentration over the range 0.5-150 µM, and a limit of detection (S/N ratio of 3) of 0.06 µM was calculated. The dual-read assay was successfully employed in the quantitation of UA in human serum and urine samples, revealing its potential for measuring UA in clinical samples.


Assuntos
Colorimetria/métodos , Corantes Fluorescentes/química , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Ácido Úrico/sangue , Ácido Úrico/urina , Técnicas Biossensoriais/métodos , Carbono/química , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , Nitrogênio/química , Fenilenodiaminas/química , Urato Oxidase/química , Ácido Úrico/química
9.
Clin Oral Investig ; 24(9): 3017-3028, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31853899

RESUMO

OBJECTIVES: This study aimed to quantitatively compare the somatosensory function changes of inferior alveolar nerve (IAN) after mandibular third molar extraction with a surgery protocol of coronectomy, as opposed to the conventional method. MATERIALS AND METHODS: Patients with a lower third molar directly contacting IAN were recruited and assigned either to a test group (coronectomy group) or a control group (conventional extraction). A standardized quantitative sensory testing (QST) battery was performed for four times: one week before surgery and the second, seventh, and 28th days after surgery. Z-scores and the loss/gain coding system were applied for each participant. RESULTS: A total of 140 molars (test group: n = 91, control group: n = 49) were enrolled. The sensitivity of the mechanical detection threshold (MDT) and pressure pain threshold (PPT) significantly increased after surgery more than before surgery in both groups (P ≤ 0.001). After the surgery, the sensitivities of the cold detection threshold (CDT), cold pain threshold (CPT), and heat pain threshold (HPT) were significantly higher in the test group than in the control group (P ≤ 0.027). The risk of IANI was significantly larger (P = 0.041) in the test group than in the control group. CONCLUSIONS: QST was a sensitive way to detect somatosensory abnormalities even with no subjective complaint caused by surgery. Coronectomy had less influence on IAN function than conventional total extraction. CLINICAL RELEVANCE: The somatosensory function changes after mandibular third molar extraction were quantitatively studied, and coronectomy was proved a reliable alternation to reduce IAN injury rate.


Assuntos
Coroa do Dente , Dente Impactado , Traumatismos do Nervo Trigêmeo , Humanos , Mandíbula/cirurgia , Nervo Mandibular , Dente Serotino/cirurgia , Estudos Prospectivos , Extração Dentária , Traumatismos do Nervo Trigêmeo/etiologia
10.
Lipids Health Dis ; 18(1): 34, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30704536

RESUMO

OBJECTIVE: Metabolic syndrome (MS) is a group of risk factors which includes hypertension, hyperglycemia, abnormal cholesterol levels, and obesity. Red blood cell distribution width (RDW) is a parameter that reflects the heterogeneity of erythrocyte volume. But the relationship between MS and RDW is intricate and remains poorly understood. We hypothesized that high RDW was associated with MS via inflammation. Our study aimed to investigate the association between RDW and MS in Chinese elderly large cohort. If RDW had a strong correlation with MS, RDW could become a predictor of MS? METHODS: We recruited 10,887 ostensibly healthy participants aged from 60 to 93 (5795 male, 5092 female). Associations between RDW and other variables were assessed by Pearson correlation. Crude and adjusted odds ratio for MS with 95% confidence intervals was calculated by binary logistic regression models. RESULTS: In elderly Chinese, RDW was significantly higher in males than in females. The prevalence of both men and women decreased with the rise of RDW. For both sexes, RDW demonstrated positive correlations with age, systolic blood pressure (0.070 in males,0.058 in females), high density lipoprotein(0.027in males,0.064 in females), negative correlations with triglycerides (- 0.120 in males,-0.074 in females) and fasting glucose (- 0.048 in males,-0.016 in females). Notably, we detected the associated reduced risks at the the third and fourth quartile of RDW in males. In women, there was no statistical significance. CONCLUSION: We found the adjusted odds ratios of MS was lower at the third and fourth quartile of RDW in males.


Assuntos
Índices de Eritrócitos , Síndrome Metabólica/sangue , Idoso , Idoso de 80 Anos ou mais , Glicemia/análise , Pressão Sanguínea , China , Estudos Transversais , Feminino , Humanos , Lipoproteínas HDL/sangue , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Triglicerídeos/sangue
11.
Endocr Pract ; 24(8): 733-739, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30113215

RESUMO

OBJECTIVE: The association between subclinical thyroid dysfunction and waist circumference (WC) is still controversial, especially from the perspective of sex differences. We aimed to explore the impact of sex on this relationship in a large Chinese cohort. METHODS: This cross-sectional study recruited 13,505 healthy participants (8,346 males, 5,159 females) who were enrolled in a health check program. Clinical data were collected. The association between subclinical thyroid dysfunction and WC of both sexes was analyzed separately after dividing WC into quartiles. Odds ratios (ORs) were calculated by binary logistic regression models, and linear regression analysis was also performed. RESULTS: The prevalence rates of subclinical hyper-and hypothyroidism were significantly lower in males. Binary logistic regression models showed that WC in females with subclinical hypothyroidism had a detrimental effect with an OR of 1.011, but the effect disappeared when we included other covariates. The other ORs indicated no significant effects. The weak negative relationship between WC and thyrotropin was also indicated by linear regression analyses with very low R2 values. CONCLUSION: The current research did not show WC as a risk factor for subclinical thyroid dysfunction in either sex. Regional and ancestral origin differences may account for the variations with other studies. ABBREVIATIONS: ALT = alanine aminotransferase; BMI = body mass index; FT3 = free triiodothyronine; FT4 = free thyroxine; TG = triglycerides; TSH = thyroid-stimulating hormone; UA = uric acid; WC = waist circumference.


Assuntos
Doenças Assintomáticas/epidemiologia , Hipertireoidismo/epidemiologia , Hipotireoidismo/epidemiologia , Obesidade Abdominal/epidemiologia , Circunferência da Cintura , Adulto , Idoso , China/epidemiologia , Estudos de Coortes , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Hipertireoidismo/sangue , Hipotireoidismo/sangue , Modelos Lineares , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Fatores Sexuais , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
12.
Angew Chem Int Ed Engl ; 53(22): 5643-7, 2014 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-24737675

RESUMO

An enantioselective synthesis of spiropyrazolones from allenoate-derived MBH acetates and pyrazolones through a phosphine-mediated [4+1] annulation process has been developed. Spiropyrazolones were readily prepared in good chemical yields and good to high enantioselectivities. This is the first asymmetric example in which α-substituted allenoates were utilized as a C4 synthon for phosphine-catalyzed [4+1] annulation.


Assuntos
Fosfinas/química , Pirazolonas/química , Compostos de Espiro/química , Catálise , Cristalografia por Raios X , Reação de Cicloadição , Conformação Molecular , Pirazolonas/síntese química , Estereoisomerismo
13.
Heliyon ; 10(9): e30286, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38765150

RESUMO

In this work, the corrosion behavior of pure Mg, Mg3Ag, Mg6Ag, and MgZnYNd alloys in different fixatives (ethyl alcohol (EA), 85 % ethyl alcohol (85 % EA), 10 % neutral buffered formalin (10 % NBF), 4 % glutaric dialdehyde (4 % GD), and 4 % paraformaldehyde (4 % PFA)) was investigated to provide a valuable reference for the selection of fixatives during the histological evaluation of Mg implants. Through the hydrogen evolution test, pH test, and corrosion morphology and product characterization, it was found that corrosion proceeded slowest in the EA and 85 % EA groups, slightly faster in 4 % GD, faster in 10 % NBF, and fastest in 4 % PFA. After corrosion, the EA group surface remained unchanged, while the 85%EA group surface developed minor cracks and warping. The 4%GD fixative formed a dense needle-like protective layer on the Mg substrate. The 10%NBF group initially grew a uniform layer, but later developed irregular pits due to accelerated corrosion. In contrast, the 4%PFA solution caused more severe corrosion attributed to chloride ions. The main corrosion products in the EA and 85%EA groups were MgO and Mg(OH)2, while the other fixatives containing diverse ions also yielded phosphates like Mg3(PO4)2 and MgHPO4. In 4 % PFA, AgCl formed on the surface of Mg6Ag alloy after corrosion. Therefore, to minimize Mg alloy corrosion without compromising staining quality, EA or 85 % EA is recommended, while 4 % PFA is not recommended due to its significant impact.

14.
Biosens Bioelectron ; 249: 115985, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38219465

RESUMO

Multidrug resistance (MDR) remains a significant challenge in cancer therapy, with inherent and acquired resistance distinct. While conventional drug selection processes enable the isolation of cancer cells with acquired multidrug resistance, identifying cancer cells with inherent drug resistance remains challenging. Herein, we proposed a molecular beacon (MB)-based strategy to identify and isolate the inherent MDR cancer cells. A lipid/PLGA core-shell nanoparticulate system (DNCP) was designed to deliver MB for intracellular MDR1 mRNA imaging. DNCP-MB - possess a surface potential of -8 mV and a size of 150 nm - demonstrated effective delivery of MB, remarkable selectivity towards the selected intracellular mRNA targets, and low cytotoxicity. Following DNCP transfection, fluorescence-activated cell sorting (FACS) was employed to differentiate MCF-7 cells into two distinct sub-populations: the Top 10 cells with a high level of MDR gene expression and the Bottom 10 cells with a low level of MDR gene expression, which represent inherent drug-resistant and non-drug-resistant cells, respectively. Intriguingly, we observed a positive correlation between elevated MDR1 mRNA expression and increased migration, enhanced proliferation rate, and tighter spheroid formation. Moreover, we conducted RNA sequencing analysis on the Top 10, Bottom 10, and MCF-7/ADR cells. The findings revealed a notable disparity in the gene ontology enrichment analysis of differentially expressed genes between the Top 10 and Bottom 10 cells when compared to the Bottom 10 and MCF-7/ADR cells. This novel approach provides a promising avenue for isolating inherent drug-resistant cells and holds significant potential in unraveling the mechanisms underlying inherent drug resistance.


Assuntos
Técnicas Biossensoriais , Neoplasias , Humanos , Doxorrubicina , Resistencia a Medicamentos Antineoplásicos/genética , Resistência a Múltiplos Medicamentos/genética , Células MCF-7 , RNA Mensageiro , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Neoplasias/genética
15.
Talanta ; 265: 124905, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37421789

RESUMO

Organophosphorus pesticides (OPs) are widely used in agricultural production, but their residues could cause pollution to the environment and living organisms. In this paper, a simple dual-readout method for OPs detection was proposed based on ChOx single enzyme inhibition. Firstly, ChOx can catalyze the production of H2O2 from choline chloride (Ch-Cl). Bifunctional iron-doped carbon dots (Fe-CDs) with good peroxidase-like activity and superior fluorescence properties can catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to blue oxidized TMB (oxTMB) by H2O2 formed, and oxTMB could quench the fluorescence of Fe-CDs. In light of the fact that OPs exhibited activity in inhibiting ChOx, less H2O2 and the decreasing oxTMB led to a result that the fluorescence of the system recovered and the solution became lighter in blue color. Moreover, the process of ChOx inhibition by OPs was analyzed by molecular docking technique and it was found that OPs interact with key amino acid residues catalyzed by ChOx (Asn510, His466, Ser101, His351, Phe357, Trp331, Glu312). Finally, a dual-mode (colorimetry and fluorescence) sensor was created for the detection of OPs with the detection limit of 6 ng/L, and was successfully used in the quantitative determination of OPs in actual samples with satisfactory results.


Assuntos
Técnicas Biossensoriais , Praguicidas , Praguicidas/análise , Compostos Organofosforados , Acetilcolinesterase/metabolismo , Peróxido de Hidrogênio/química , Simulação de Acoplamento Molecular , Técnicas Biossensoriais/métodos , Colorimetria/métodos
16.
J Dent ; 139: 104762, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37898432

RESUMO

OBJECTIVES: The study represents a preliminary evaluation of the accuracy of the dynamic navigation system (DNS) in coronectomy of the mandibular third molar (M3M). METHODS: The study included participants with an impacted M3M near the inferior alveolar canal. The coronectomy planes were designed before the surgery using cone-beam computed tomography (CBCT) imaging data and then loaded into the DNS program. Intraoperatively, the navigation system was used to guide the complete removal of the target crown. Postoperative CBCT imaging was used to assess any three-dimensional deviations of the actual postoperative from the planned preoperative section planes for each patient. RESULTS: A total of 12 patients (13 teeth) were included. The root mean square (RMS) deviation of the preoperatively designed plane from the actual postoperative surface was 0.69 ± 0.21 mm, with a maximum of 1.45 ± 0.83/-1.87 ± 0.63 mm deviation. The areas with distance deviations < 1 mm, 1-2 mm, and 2-3 mm were 71.97 ± 5.72 %, 22.96 ± 6.57 %, and 4.52 ± 2.28 %, respectively. Most patients showed extremely high convexity of the surface area located in the mesial region adjacent to the base of the extraction socket. There was no observable evidence of scratching of the buccolingual bone plate at the base of the extraction socket by the handpiece drill. CONCLUSIONS: These results provide preliminary support for the use of DNS-based techniques when extracting M3M using a buccal approach. This would improve the accuracy of coronectomy and reduce the potiential damage to the surrounding tissue. CLINICAL SIGNIFICANCE: DNS is effective for guiding coronectomy.


Assuntos
Dente Serotino , Traumatismos do Nervo Trigêmeo , Humanos , Dente Serotino/diagnóstico por imagem , Dente Serotino/cirurgia , Projetos Piloto , Extração Dentária , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Tomografia Computadorizada de Feixe Cônico , Computadores , Nervo Mandibular/diagnóstico por imagem
17.
ACS Appl Bio Mater ; 6(11): 4703-4713, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37865928

RESUMO

The utilization of guided tissue regeneration membranes is a significant approach for enhancing bone tissue growth in areas with bone defects. Biodegradable magnesium alloys are increasingly being used as guided tissue regeneration membranes due to their outstanding osteogenic properties. However, the degradation rates of magnesium alloy bone implants documented in the literature tend to be rapid. Moreover, many studies focus only on the initial 3-month period post-implantation, limiting their applicability and impeding clinical adoption. Furthermore, scant attention has been given to the interplay between the degradation of magnesium alloy implants and the adjacent tissues. To address these gaps, this study employs a well-studied magnesium-aluminum (Mg-Al) alloy membrane with a slow degradation rate. This membrane is implanted into rat skull bone defects and monitored over an extended period of up to 48 weeks. Observations are conducted at various intervals (2, 4, 8, 12, 24, and 48 weeks) following the implantation. Assessment of degradation behavior and tissue regeneration response is carried out using histological sections, micro-CT scans, and scanning electron microscopy (SEM). The findings reveal that the magnesium alloy membranes demonstrate remarkable biocompatibility and osteogenic capability over the entire observation duration. Specifically, the Mg-Al alloy membranes sustain their structural integrity for 8 weeks. Notably, their osteogenic ability is further enhanced as a corrosion product layer forms during the later stages of implantation. Additionally, our in vitro experiments employing extracts from the magnesium alloy display a significant osteogenic effect, accompanied by a notable increase in the expression of osteogenic-related genes. Collectively, these results strongly indicate the substantial potential of Mg-Al alloy membranes in the context of guided tissue regeneration.


Assuntos
Ligas , Magnésio , Ratos , Animais , Ligas/farmacologia , Ligas/química , Magnésio/farmacologia , Magnésio/química , Alumínio/farmacologia , Regeneração Óssea , Osteogênese
18.
Anal Chim Acta ; 1221: 340110, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35934352

RESUMO

A novel sulfate-loaded iron-nitrogen co-doped carbon quantum dots (SO42--CQDs)-based fluorescent method was synthesized by the facile and environmentally friendly pyrolysis of persimmon frost (carbon source) and (NH4)2Fe(SO4)2·6H2O. After SMMC-7721 cells were incubated with the SO42--CQDs for 24 h, more than 95% of the cells remained viable, even at a high concentration of the SO42--CQDs, indicating excellent biocompatibility and low toxicity. In addition, it was able to be taken up by the cells to emit their bright blue fluorescence after excitation at 365 nm, indicating suitable cell permeability. The SO42--CQDs also exhibited a unique response to changes in pH, which was applied in the detection of OPs by relying on the production of acetic acid from the hydrolysis of acetylcholine (ACh) by acetylcholinesterase (AChE), which decreased the pH and engendered an increase in the fluorescence of the SO42--CQDs; however, the inhibition of AChE by glyphosate resulted in little influence on fluorescence intensity due to the lack of acetic acid produced. This mechanism was the basis for the development of a sensitive assay for the detection of glyphosate. The resulting assay had a limit of detection of 0.066 ng/mL. Furthermore, the method was successfully applied for the precise and accurate monitoring of the concentration, distribution, and variation of glyphosate residues in chives and cultivated soil. Therefore, the proposed method was anticipated to provide a promising alternative for other detection methods to enable the reliable analysis of OPs in food products.


Assuntos
Pontos Quânticos , Acetilcolinesterase , Carbono/química , Corantes Fluorescentes/química , Glicina/análogos & derivados , Concentração de Íons de Hidrogênio , Nitrogênio/química , Pontos Quânticos/química , Glifosato
19.
Front Oncol ; 12: 889284, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35957867

RESUMO

Objectives: Anaplastic thyroid cancer (ATC) cells cannot retain the radionuclide iodine 131 (131I) for treatment due to the inability to uptake iodine. This study investigated the feasibility of combining radionuclides with photothermal agents in the diagnosis and treatment of ATC. Methods: 131I was labeled on human serum albumin (HSA) by the standard chloramine T method. 131I-HSA and indocyanine green (ICG) were non-covalently bound by a simple stirring to obtain 131I-HSA-ICG nanoparticles. Characterizations were performed in vitro. The cytotoxicity and imaging ability were investigated by cell/in vivo experiments. The radio-photothermal therapy efficacy of the nanoparticles was evaluated at the cellular and in vivo levels. Results: The synthesized nanoparticles had a suitable size (25-45 nm) and objective biosafety. Under the irradiation of near-IR light, the photothermal conversion efficiency of the nanoparticles could reach 24.25%. In vivo fluorescence imaging and single-photon emission CT (SPECT)/CT imaging in small animals confirmed that I-HSA-ICG/131I-HSA-ICG nanoparticles could stay in tumor tissues for 4-6 days. Compared with other control groups, 131I-HSA-ICG nanoparticles had the most significant ablation effect on tumor cells under the irradiation of an 808-nm laser. Conclusions: In summary, 131I-HSA-ICG nanoparticles could successfully perform dual-modality imaging and treatment of ATC, which provides a new direction for the future treatment of iodine-refractory thyroid cancer.

20.
Bioinorg Chem Appl ; 2022: 4941635, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371192

RESUMO

We explored the feasibility and efficacy of a degradable magnesium (Mg) alloy guided bone regeneration (GBR) in the treatment of bone defects after tooth extraction. A GBR membrane (MAR-Gide (MG)) was used to treat a mandibular second molar (M2M)-distal bone defect (DBD). In eight beagle dogs, bilateral mandibular second and fourth premolars were hemi-sected. The distal roots were removed to create a two-wall bony defect of dimension 5 mm × 5 mm × 5 mm to simulate M2M-DBD. Thirty-two bone defects were assigned randomly into four groups according to GBR membranes (MG and Bio-Gide (BG)) applied and the time of killing (3 months and 6 months after surgery). The osteogenesis of bone defects and MG degradation were analyzed using micro-CT, histology (staining, tartrate-resistant acid phosphatase), and inductively coupled plasma mass spectrometry. MG did not increase the prevalence of infection, wound dehiscence, or subcutaneous emphysema compared with those using BG. Trabecular volume/total volume at 3 months (63.71 ± 10.4% vs. 59.97 ± 8.94%) was significantly higher in the group MG than that in the group BG. Implanted MG was degraded completely within 3 months, and "island-shaped" new bone was found near MG degradation products. A significant difference was not found in vertical bone height or percent of new bone formation (45.44 ± 12.28% vs. 43.49 ± 7.12%) between the groups. The concentration of rare-earth elements in mandibular lymph nodes of the group MG was significantly higher than that of the group BG (P ≤ 0.017) but did not lead to histopathological changes. In summary, MG exhibited good biocompatibility and clinical applicability compared with BG in vivo. The osteogenic effect of MG could be enhanced by regulating the degradation rate of Mg-alloy.

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