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1.
Int J Mol Sci ; 23(16)2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-36012750

RESUMEN

Compared to the equiatomic or near-equiatomic NiTinol alloys, Ni-rich NiTi alloys are suitable to be employed in structural applications as they exhibit higher hardness and are dimensionally stable. This research aimed to process two different grades of Ni-rich NiTi alloys, 58NiTi and 60NiTi, from Ni-Ti powder mixtures having about 58 wt.% and 60 wt.% Ni, respectively. This was performed by a laser powder bed fusion technique. At the first stage of this research, the printability of the used powder mixtures was investigated by applying different sets of printing parameters. Two appropriate sets were then selected to print the samples. Microstructural study of the printed parts revealed the existence of inhomogeneity in the microstructures. In addition, depending on the applied set of parameters, some amounts of cracks and pores were also present in the microstructure of these parts. Postprinting hot isostatic pressing procedures, performed at different temperatures, were developed to cause the reaction of phases, homogenize the parts, and possibly eliminate the existing flaws from the samples. Effects of these applied treatments on the microstructure, phase composition, density, dimensional integrity, and hardness of parts were sequentially studied. In essence, 58NiTi and 60NiTi parts having phase compositions complying with those of the equilibrium phase diagram were obtained in this research. However, the mentioned cracks and pores, formed in the microstructure of as-printed parts, could not be fully removed by postprocessing treatments.


Asunto(s)
Aleaciones , Titanio , Aleaciones/química , Rayos Láser , Polvos , Impresión Tridimensional , Titanio/química
2.
J Craniofac Surg ; 25(3): 968-71, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24717315

RESUMEN

INTRODUCTION: A series of retrospectively recorded patients with cleft lip and palate was uniquely investigated to demonstrate and analyze the complications after cleft repairing operations in a selected Chinese population. MATERIAL AND METHODS: From January 2005 to January 2012, a selected group of 2100 patients with cleft lip and/or palate who have complete records were chosen from a large sample in the units. Complete data were retrieved, including sex, age, clinical classification, surgical modality, complications, and follow-up results. The complications were classified into 2 categories: early and long-term complications. After surgery, most patients with cleft lip remained in the hospital for 7 days and cleft palate repairs for 10 days. A standard regimen of antibiotics was administered for 3 to 5 days clinically. RESULTS: Of the 2100 patients, there were 1360 males and 760 females who had congenital cleft deformity with complete clinical records in the department of oral and maxillofacial surgery. The age distribution was as follows: 1600 patients in the group of 3 months to 2 years, 320 patients in the group of 2 to 10 years, 130 patients in the group of 11 to 19 years, and 50 patients in the group of older than 20 years. As to the treatment modality, cleft lips were repaired by rotation advancement method with various minor modifications or Tennison modality. The cleft palates were closed using the von Langenbeck, Veau/Wardill/Kilner, or Furlow technique. The overall complication rate was 16.8% of the patients. Of the early complications, there were 6 cases of asphyxia, 17 cases of pyrexia, 5 cases of edema of the respiratory tract, 8 cases of upper respiratory tract infection, 6 cases of bronchiolitis, 7 cases of pneumonia, 9 cases of diarrhea and vomiting, 6 cases of hemorrhage, 5 patients of odontoptosis, 11 cases of erosion of the corner of mouth, 5 cases of drowsiness, 11 cases of incision dehiscence, 9 cases of wound infection, 6 cases of palatal dehiscence/fistula, 3 cases of nostril floor breakdown, 7 cases of conjunctivitis, as well as 3 cases of mortality. The long-term complications included 30 cases of secondary lip/nasal deformity, 10 cases of dehiscence of lip, 14 cases of palatal fistula/decencies, 18 cases of hearing problem/otitis media, 21 cases of poor ventilation/snoring, 66 cases of velopharyngeal incompetence, and 58 cases of voice disorder. CONCLUSIONS: Complications after cleft surgery are unavoidable clinically. More attention should be paid to the etiologic factors to minimize the prevalence of complications. Mortality can be found in patients with cleft, which is a deadly complication. Problems of respiratory tract and hemorrhage should be emphasized and treated seriously.


Asunto(s)
Labio Leporino/cirugía , Fisura del Paladar/cirugía , Procedimientos de Cirugía Plástica , Complicaciones Posoperatorias/etiología , Cirugía Bucal , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Tiempo de Internación , Masculino , Estudios Retrospectivos , Cirugía Bucal/métodos , Adulto Joven
3.
Talanta ; 280: 126750, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39213890

RESUMEN

The discovery of pancreatic lipase (PL) inhibitors is an essential route to develop new anti-obesity drugs. In this experiment, chitosan was used to add amino groups to cellulose filter paper (CFP) and then glutaraldehyde was used to covalently combine PL with amino-modified CFP through the Schiff base reaction. Under optimal immobilization conditions, CFP immobilized PL has a wide range of pH and temperature tolerance, as well as excellent reproducibility, reusability and storage stability. Subsequently, 26 natural products (NPs) were screened by immobilized PL with black tea extract having the highest inhibition rate. Three compounds with binding effects on PL (epigallocatechin gallate, theaflavin-3-gallate and theaflavin-3,3'-digallate) were captured. Molecular docking proved that these three compounds have a strong binding affinity for PL. Fluorescence spectra further revealed that theaflavin-3,3'-digallate could statically quench the intrinsic fluorescence of pancreatic lipase. The molecular docking and thermodynamic parameters indicated that electrostatic interaction was considered as the main interaction force between PL and theaflavin-3,3'-digallate. Finally, the potential anti-obesity targets and pathways of the three compounds were discussed through network pharmacology. This study not only proposes a simple and efficient method for screening PL inhibitors, but also sheds light on the anti-obesity mechanism of active compounds in black tea.


Asunto(s)
Fármacos Antiobesidad , Celulosa , Inhibidores Enzimáticos , Enzimas Inmovilizadas , Lipasa , Simulación del Acoplamiento Molecular , Lipasa/antagonistas & inhibidores , Lipasa/metabolismo , Lipasa/química , Celulosa/química , Celulosa/análogos & derivados , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/antagonistas & inhibidores , Enzimas Inmovilizadas/metabolismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Fármacos Antiobesidad/farmacología , Fármacos Antiobesidad/química , Farmacología en Red , Páncreas/enzimología , Catequina/análogos & derivados , Catequina/química , Catequina/farmacología , Catequina/metabolismo , Papel , Té/química , Evaluación Preclínica de Medicamentos
4.
Clin Oral Investig ; 17(9): 2003-10, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23358705

RESUMEN

OBJECTIVE: The purpose of this study is to retrospectively explore the utilization of coralline hydroxyapatite in maxillary sinus augmentation. METHOD: One hundred and eighteen cases of sinus lift with coralline hydroxyapatite (CHA) were included in this study. In detail, simultaneous implantation was conducted in 78 patients (174 implants) and delayed implantation was done in 40 cases (82 implants) around 6 months after bone transplantation. The clinical features and X-ray radiographs after operation were analyzed to evaluate osseointegration procedures according to a planned medical follow-up. In the delayed group, around 6 months, a bone biopsy was taken just during implant placement in order to evaluate the new formed bone from a histological and histomorphometrical point of view. A further 6 months later, abutment connection was performed, and the patients received prosthetic restoration of the missing teeth. RESULT: Clinically, the incisions healed well. No abnormal reactions were found during follow-up period. All the 174 simultaneous implants were successful after 1-5 years of medical review; Out of 82 delayed implants, 3 were found to be loose. Histologically, all the specimens showed signs of active remodeling, and all the tissues had a large amount of osteocyte at sixth month after sinus augmentation. New bone formed dramatically. Radiologically, the density of CHA gradually reduced since the beginning of the third month, and CHA may be completely resolved at about fifth year. CONCLUSION: CHA is proven an ideal bone graft material for its reliable clinical results and favorable histocompatibility in the treatment of sinus atrophy or other kinds of insufficient bone volume in this region. Moreover, CHA's signal application can achieve desired clinical effect. CLINICAL RELEVANCE: This study shows the clinic application of CHA in maxillary sinus augmentation. Compared with popular mixture of autogenous bone and grafting materials, our results show CHA's signal application can achieve ideal osseointegration interface and satisfying clinic effect.


Asunto(s)
Cerámica/farmacología , Hidroxiapatitas/farmacología , Elevación del Piso del Seno Maxilar , Humanos , Estudios Retrospectivos
5.
Sci Total Environ ; 789: 147938, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34058585

RESUMEN

As an emerging pollutant, microplastic has been demonstrated to widely cover water and sediments in marine and freshwater environments globally. Due to the differences in the regional functions of cities, the abundance and characteristics of microplastic pollution in rivers are different. Taking the Minjiang River as the research object, which flows through the Chengdu Plain, the abundance, composition, shape, and size of microplastics in the water and sediments of the Minjiang River were investigated. The results showed that serious microplastic pollution occurred in the Chengdu section of the Minjiang River, with an abundance ranging from 6.11-44.08 n/L in the water and from 573.84-2878.97 n/kg in the sediments. By using the "regional function index (Q)", the relationships between the characteristics of microplastic pollution and regional functions were analyzed. Areas with a high Q proved to be more polluted by microplastics. Densely populated areas with large construction areas and high human activity intensity tended to generate microplastics with larger sizes and a more fiber-like shapes. Rayon (RA) and nylon (PA) were identified as typical urban microplastics, while polypropylene (PP) and polyethylene (PE) were identified as typical agricultural microplastics. This study elucidated the microplastic pollution in the Chengdu section of the Minjiang River, a tributary in the upper reaches of the Yangtze River. It also provided a new direction for the study of microplastic pollution characteristics of freshwater environments with different regional functions and microplastic pollution source control.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Ciudades , Monitoreo del Ambiente , Humanos , Plásticos , Ríos , Contaminantes Químicos del Agua/análisis
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