Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 9 de 9
Filter
Add more filters










Database
Publication year range
1.
Int J Dent ; 2022: 8332631, 2022.
Article in English | MEDLINE | ID: mdl-35251183

ABSTRACT

OBJECTIVE: This review aims to summarize different kinds of applications of minimally invasive surgery in improving facial aging to provide a comprehensive and accurate introduction on the issue of esthetic treatment of facial skin. Overview. In the twentieth century, facial rejuvenation has become a new beauty trend. Facial cosmetology has entered a period of antiaging and rejuvenation therapies and microplastic surgery. The pursuit of beauty has promoted the development of minimally invasive plastic surgery. This review introduces the possible causes of facial aging and its related topics with a focus on facial injectable drugs, such as botulinum toxin, main filler materials (hyaluronic acid, calcium hydroxyapatite, poly L-lactic acid, collagen, autologous fat, and polymethyl methacrylate), and some current antiwrinkle technologies, such as thread lift and radiofrequency rhytidectomy. CONCLUSIONS: Despite the difference in mechanisms of action, each technique can address facial aging involving the loss of collagen, displacement and enlargement of fat, and muscle relaxation. Combinations of these treatments can provide patients with reasonable, comprehensive, and personalized treatment plans.

2.
Scanning ; 2021: 9950131, 2021.
Article in English | MEDLINE | ID: mdl-34367410

ABSTRACT

Three-dimensional (3D) printing technologies are advanced manufacturing technologies based on computer-aided design digital models to create personalized 3D objects automatically. They have been widely used in the industry, design, engineering, and manufacturing fields for nearly 30 years. Three-dimensional printing has many advantages in process engineering, with applications in dentistry ranging from the field of prosthodontics, oral and maxillofacial surgery, and oral implantology to orthodontics, endodontics, and periodontology. This review provides a practical and scientific overview of 3D printing technologies. First, it introduces current 3D printing technologies, including powder bed fusion, photopolymerization molding, and fused deposition modeling. Additionally, it introduces various factors affecting 3D printing metrics, such as mechanical properties and accuracy. The final section presents a summary of the clinical applications of 3D printing in dentistry, including manufacturing working models and main applications in the fields of prosthodontics, oral and maxillofacial surgery, and oral implantology. The 3D printing technologies have the advantages of high material utilization and the ability to manufacture a single complex geometry; nevertheless, they have the disadvantages of high cost and time-consuming postprocessing. The development of new materials and technologies will be the future trend of 3D printing in dentistry, and there is no denying that 3D printing will have a bright future.


Subject(s)
Computer-Aided Design , Printing, Three-Dimensional , Dentistry
3.
Sci Total Environ ; 783: 147091, 2021 Aug 20.
Article in English | MEDLINE | ID: mdl-34088115

ABSTRACT

Dissolved organic matter (DOM) is an important organic matter fraction that affects many biological and chemical processes in soil. Biochar can change soil DOM while the effects were paradoxical, and contributions of biochar to soil DOM was not clear yet. In this study, excitation-emission matrix (EEM) fluorescence spectroscopy was applied to determine the biochar-induced changes of DOM composition. Batch experiments were conducted to quantify the contributions of biochar to soil DOM. Biochars were prepared by pyrolyzing wheat straw (S300/700) and cow manure (M300/700) at 300 and 700 °C, respectively. Generally, biochar increased the humification of soil DOM possibly by the release of indigenous DOM and selective adsorption of the small molecule DOM. Besides, contributions of S300 and M300 to soil DOM (37-91%) were higher than that of S700 and M700 (2-19%) irrespective of application rates. The indigenous DOM released from S300 and M300 was 6.4-12.1 times more than the soil DOM adsorbed by S300 and M300, leading to the increase of DOM content. Contrarily, the DOM from S700 and M700 was only 11-17% of the soil DOM adsorbed by them, resulting in the decrease of DOM content. In addition, contributions of biochar to soil DOM increased as the application rate increased, especially for S300 and M300. This study indicated that the release and adsorption of DOM were the key processes determining the effects of biochar on soil DOM, which were closely related to the pyrolysis temperature and application rate of biochar.

4.
Environ Pollut ; 237: 308-317, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29499574

ABSTRACT

Polybrominated diphenyl ethers (PBDEs) are toxic chemicals widely distributed in the environment, but few studies are available on their potential toxicity to rice at metabolic level. Therefore we exposed ten rice (Oryza sativa) varieties to 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), a predominant congener of PBDEs, in hydroponic solutions with different concentrations. Two varieties that showed different biological effects to BDE-47, YY-9 and LJ-7, were screened as sensitive and tolerant varieties according to changes of morphological and physiological indicators. Metabolic research was then conducted using gas chromatography-mass spectrometry combined with diverse analyses. Results showed that LJ-7 was more active in metabolite profiles and adopted more effective antioxidant defense machinery to protect itself against oxidative damages induced by BDE-47 than YY-9. For LJ-7, the contents of 13 amino acids and 24 organic acids, especially l-glutamic acid, beta-alanine, glycolic acid and glyceric acid were up-regulated significantly which contributed to scavenging reactive oxygen species. In the treatment of 500 µg/L BDE-47, the contents of these four metabolites increased by 33.6-, 19.3-, 10.6- and 10.2-fold, respectively. The levels of most saccharides (such as d-glucose, lactulose, maltose, sucrose and d-cellobiose) also increased by 1.7-12.4 fold which promoted saccharide-related biosynthesis metabolism. Elevation of tricarboxylic acid cycle and glyoxylate and dicarboxylate metabolism enhanced energy-producing processes. Besides, the contents of secondary metabolites, chiefly polyols and glycosides increased significantly to act on defending oxidative stress induced by BDE-47. In contrast, the levels of most metabolites decreased significantly for YY-9, especially those of 13 amino acids (by 0.9%-67.1%) and 19 organic acids (by 7.8%-70.0%). The positive metabolic responses implied LJ-7 was tolerant to BDE-47, while the down-regulation of most metabolites indicated the susceptible nature of YY-9. Since metabolic change might affect the yield and quality of rice, this study can provide useful reference for rice cultivation in PBDEs-polluted areas.


Subject(s)
Halogenated Diphenyl Ethers/toxicity , Oryza/metabolism , Water Pollutants, Chemical/toxicity , Antioxidants , Ether , Gas Chromatography-Mass Spectrometry , Halogenated Diphenyl Ethers/metabolism , Hydroponics , Metabolomics , Oryza/drug effects , Oxidative Stress/physiology
5.
Environ Pollut ; 235: 692-699, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29339338

ABSTRACT

Decabromodiphenyl ether (BDE-209), as a major component of brominated flame retardants, has been detected in the agricultural soil in considerable amount. Given that BDE-209 is toxic, ubiquitous and persistent, BDE-209 might induce toxic effects on rice cultivars planted in contaminated soil. A comparative study was conducted on phytotoxicities and GC-MS based antioxidant-related metabolite levels to investigate the differences of phytotoxicities of BDE-209 to rice cultivars in Yangtze River Delta of China. Rice seedlings were treated with BDE-209 at 0, 10, 50, 100 and 500 µg/L in a hydroponic setup. Results showed that BDE-209-induced phytotoxicites were cultivar-dependent and that the antioxidant defense systems in the cultivars were disturbed differently. Among the three selected cultivars (Jiayou 5, Lianjing 7 and Yongyou 9), Jiayou 5 and Lianjing 7 displayed lower toxic effects than Yongyou 9 in terms of the growth inhibition, lipid peroxidation and DNA damage. The increases of antioxidant enzymes were significantly higher in Jiayou 5 and Lianjing 7 than those in Yongyou 9. Multivariate analysis of antioxidant-related metabolites in the three cultivars indicated that l-tryptophan and l-valine were the most important ones among 10 metabolites responsible for the separation of cultivars. The up-regulation of l-tryptophan and l-valine were likely plant strategies to increase their tolerance. The current results provided an insight into the development of rice cultivars with higher BDE-209 tolerance.


Subject(s)
Flame Retardants/toxicity , Halogenated Diphenyl Ethers/toxicity , Oryza/drug effects , Soil Pollutants/toxicity , Antioxidants/metabolism , China , Hydroponics , Lipid Peroxidation/drug effects , Oryza/metabolism , Seedlings/drug effects , Seedlings/metabolism , Soil/chemistry , Soil Pollutants/metabolism , Tryptophan/metabolism
6.
Environ Sci Pollut Res Int ; 25(1): 12-17, 2018 Jan.
Article in English | MEDLINE | ID: mdl-27699658

ABSTRACT

Hydroxylated polychlorinated biphenyls (OH-PCBs) have been found in the environment with high toxicity. Recently, methoxylated polychlorinated biphenyls (MeO-PCBs) were identified as new pollutants and detected in sewage sludge. This study presents a detailed investigation on the uptake, translocation, and metabolism of OH-PCBs and MeO-PCBs in typical crops including maize, wheat, and rice. The interconversion between OH-PCBs and MeO-PCBs were observed. Demethylation of MeO-PCBs was favored over methylation of OH-PCBs. The metabolites were mainly generated in the roots and then translocated to the shoots. Analog-specific differences showed that the accumulation amounts of MeO-PCBs were higher than those of OH-PCBs in the crops. The translocation abilities followed this order: 3'-OH-CB-65 > 4'-OH-CB-101 > 3'-MeO-CB-65 > 4'-MeO-CB-101. The conversion rates were generally higher for 4'-OH-CB-101 than 3'-OH-CB-65 and higher for 4'-MeO-CB-101 than 3'-MeO-CB-65. Interspecies variability among the crops was also observed. The amounts of metabolites and acropetal translocation inside the plants were the greatest for maize. However, the concentration of compounds normalized by the mass of corresponding plant tissue was highest in wheat. These findings provide valuable information for a better understanding of the phytoaccumulation and phytotransformation of OH-PCBs and MeO-PCBs.


Subject(s)
Environmental Pollutants/metabolism , Oryza/metabolism , Polychlorinated Biphenyls/metabolism , Triticum/metabolism , Zea mays/metabolism , Biological Transport , Environmental Pollutants/chemistry , Hydroxylation , Methylation , Models, Theoretical , Polychlorinated Biphenyls/chemistry , Sewage/chemistry , Species Specificity , Structure-Activity Relationship
7.
RSC Adv ; 8(26): 14221-14228, 2018 Apr 17.
Article in English | MEDLINE | ID: mdl-35540748

ABSTRACT

A series of Ag-K/MnO2 nanorods with various molar ratios of K/Ag were synthesized by a conventional wetness incipient impregnation method. The as-prepared catalysts were used for the catalytic oxidation of HCHO. The Ag-K/MnO2 nanorods with an optimal K/Ag molar ratio of 0.9 demonstrated excellent HCHO conversion efficiency of 100% at a low temperature of 60 °C. The structures of the samples were investigated by BET, TEM, SEM, XRD, H2-TPR, O2-TPD and XPS. The results showed that Ag-0.9K/MnO2-r exhibited more facile reducibility and greatly abundant surface active oxygen species, endowing it with the best catalytic activity of the studied catalysts. This work provides new insights into the development of low-cost and highly efficient catalysts for the removal of HCHO.

8.
Zhongguo Gu Shang ; 24(10): 834-7, 2011 Oct.
Article in Chinese | MEDLINE | ID: mdl-22097131

ABSTRACT

OBJECTIVE: To introduce and evaluate the clinical effects of percutaneous reduction and Kirschner pin fixation for the treatment of intraarticular fractures of the calcaneus in children. METHODS: From March 2001 to February 2009,12 patients with intraarticular calcaneal fractures were treated by percutaneous reduction and Kirschner pin fixation (13 feet). There were 8 males and 4 females,ranging in age from 3 to 14,with an average of 8.7 years. According to Essex-Lopresti classification, among 5 feet were tongue fractures and 8 feet were compressed fractures. According to Sanders classification, 9 feet were type II and 4 feet were type III. The Biihler angle and Gissane angle of the calcaneus were obtained before and after operation. All patients were evaluated according to Maryland Foot Score. RESULTS: All the patients were followed up for 16-71 months (means 35.9 months),and all the incisions were healed without complications and infection. The preoperative X-ray film showed that Böhler angle was (19.7+/-5.3) degrees, Gissane angle was (137.3+/-7.5) degrees. The postoperative X-ray film demonstrated that Böhler angle was (32.6+/-3.7) degrees, Gissane angle was (125.4+/-2.9) degrees. There was a significant difference between preoperative and postoperative (P<0.01). The average Maryland score was 96.3+/-2.4 (range, 92 to 100 points). CONCLUSION: Percutaneous reduction and Kirschner pin fixation is an effective minimally invasive way to treat intraarticular fractures of the calcaneus in children, it has many advantages such as minimal invasion, reliable fixation and satisfactory effects.


Subject(s)
Bone Nails , Calcaneus/injuries , Fracture Fixation, Internal/methods , Intra-Articular Fractures/surgery , Adolescent , Calcaneus/surgery , Child , Child, Preschool , Female , Humans , Male
9.
Zhongguo Gu Shang ; 24(8): 681-3, 2011 Aug.
Article in Chinese | MEDLINE | ID: mdl-21928679

ABSTRACT

OBJECTIVE: To study the clinical effects of AO distal humerus plate (DHP) for the treatment of distal humeral fractures in elderly osteoporotic patients. METHODS: From September 2008 to January 2010, 18 elderly osteoporotic patients with distal humeral fractures were treated with open reduction and internal fixation with DHP. There were 3 males and 15 females, ranging in age from 62 to 83 years (averaged, 71.4 years). According to AO classification, 1 patient was Type A2, 3 patients were Type A3; 2 patients were Type B1, 2 patients were Type B2; 3 patients were Type C1, 4 patients were Type C2, 3 patients were Type C3. The surgical approaches were either bilateral or via olecranon process of ulna. Early mobilization was initiated after surgery. Functional results were evaluated according to the Mayo elbow performance score (MEPS). RESULTS: The average duration of follow-up was 14.6 months (ranged from 11 to 24 months). All the patients had a complete healing of their fractures. There was no infection, hardware failure or loss of reduction after the operations. The average Mayo elbow performance score (MEPS) was (92.2 +/- 9.6) (65 to 100 points), among which the score of pain was (42.5 +/- 5.8) (30 to 45 points), the score of motion range was (19.2 +/- 1.9) (15 to 20 points), the score of stability was (9.2 +/- 1.9) (5 to 10 points), and the score of function was (21.4 +/- 2.9) (15 to 25 points). According to MEPS, 11 patients got excellent results, 5 good and 2 fair. CONCLUSION: Treatment of distal humeral fractures in elderly osteoporotic patients with AO distal humeral plates can obtain immediate stabilization which facilitates early mobilization of the elbow.


Subject(s)
Bone Plates , Fracture Fixation, Internal/methods , Humeral Fractures/surgery , Osteoporotic Fractures/surgery , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged
SELECTION OF CITATIONS
SEARCH DETAIL
...