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1.
J Prosthet Dent ; 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38493065

RESUMEN

STATEMENT OF PROBLEM: A defective socket is common after tooth extraction in the esthetic zone, but whether an implant can be immediately placed in a defective socket is unclear. PURPOSE: The purpose of this systematic review and meta-analysis was to summarize relevant studies within the last 20 years on implant survival and changes in soft and hard tissues after immediate implant placement in esthetic areas with socket defects. MATERIAL AND METHODS: A search was conducted for the relevant studies in the PubMed/Medline, the Cochrane Library, Web of Science, and Embase databases from January 2000 to March 2022. The literature review, data retrieval, and judgment whether the included studies had a risk of bias were handled independently by 2 reviewers, and a single-arm meta-analysis was performed using a statistical software program. RESULTS: A total of 23 studies evaluating the immediate implant placement of 630 implants (9 studies without a flap and 14 studies with a flap) were included. A 98.1% implant survival rate (95% confidence interval (CI): 96.2%, 100.0%) was determined. Marginal bone loss (MBL) at 6, 12, and ≥24 months were 1.03 mm (95%CI: 1.02, 1.03), 0.72 mm (0.72, 0.73), and 1.15 mm (1.14, 1.16). Gingival recession at 12 months was 0.25 mm (95%CI: 0.17, 0.33). The pink esthetic score (PES) were 12.34 (95%CI: 12.16, 12.52) at 12 months and 12.58 (12.39, 12.76) at ≥24 months. CONCLUSIONS: Current evidence shows that immediate implant placement into defective sockets in esthetic areas is feasible. Immediate implant placement can have a relatively good therapeutic effect in terms of implant survival rate, MBL, gingival recession, and PES.

2.
Small ; 19(42): e2301638, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37345962

RESUMEN

Developing composite materials with optimized mechanics, degradation, and bioactivity for bone regeneration has long been a crucial mission. Herein, a multifunctional Mg/Poly-l-lactic acid (Mg/PLLA) composite membrane based on the "materials plain" concept through the accumulative rolling (AR) method is proposed. Results show that at a rolling ratio of 75%, the comprehensive mechanical properties of the membrane in the rolling direction are self-reinforced significantly (elongation at break ≈53.2%, tensile strength ≈104.0 MPa, Young's modulus ≈2.13 GPa). This enhancement is attributed to the directional arrangement and increased crystallization of PLLA molecular chains, as demonstrated by SAXS and DSC results. Furthermore, the AR composite membrane presents a lamellar heterostructure, which not only avoids the accumulation of Mg microparticles (MgMPs) but also regulates the degradation rate. Through the contribution of bioactive MgMPs and their photothermal effect synergistically, the membrane effectively eliminates bacterial infection and accelerates vascularized bone regeneration both in vitro and in vivo. Notably, the membrane exhibits outstanding rat skull bone regeneration performance in only 4 weeks, surpassing most literature reports. In short, this work develops a composite membrane with a "one stone, four birds" effect, opening an efficient avenue toward high-performance orthopedic materials.


Asunto(s)
Regeneración Ósea , Poliésteres , Ratas , Animales , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Poliésteres/química , Bacterias
3.
J Craniofac Surg ; 34(8): e733-e736, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37428985

RESUMEN

This study aimed to introduce the use of an acellular dermal matrix (ADM) as a posterior lamellar substitution for full-thickness eyelid reconstruction after malignant tumor excision. After resection of the malignant eyelid tumors, anterior lamellar defects were repaired using direct sutures and pedicled flaps in 20 patients (15 men and 5 women). ADM was used to replace the tarsal plate and the conjunctiva. All patients were followed up for 6 months or more to assess the functional and esthetic outcomes of the procedure. The flaps survived in all but 2 cases, wherein they necrosed due to insufficient blood supply. The functionality and esthetic outcomes were excellent in 10 and 9 patients, respectively. There were no changes in visual acuity or corneal epithelial damage after the surgery. The eyeball movement was good. Corneal irritation no longer appeared, and patient comfort was maintained. Furthermore, no tumor recurrence occurred in any patient. ADM is a valuable posterior lamellar material for the full-thickness reconstruction of eyelid defects after the resection of malignant tumors on the eyelids.


Asunto(s)
Dermis Acelular , Neoplasias de los Párpados , Procedimientos de Cirugía Plástica , Masculino , Humanos , Femenino , Estética Dental , Colgajos Quirúrgicos/cirugía , Párpados/cirugía , Neoplasias de los Párpados/cirugía
4.
BMC Oral Health ; 23(1): 364, 2023 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-37277764

RESUMEN

BACKGROUND: The objective of this study was to investigate the characteristics of emergencies and the requirement for emergency treatment after the suspension of orthodontic appointments. The attitude towards orthodontic treatment preference was evaluated as well, including receiving orthodontic treatment and the preference for orthodontic appliances. SUBJECTS AND METHODS: An electronic questionnaire was distributed to the patients, including 4 sections: Section 1 - demographic and basic information; Section 2 - the characteristics of emergencies and emergency treatment requirements; Section 3 - the NRS-11 for pain and Manchester Orofacial Pain Disability Scale used to evaluate the intensity of orofacial pain and disability; and Section 4 - attitudes towards receiving orthodontic treatment and appliance preference. Descriptive statistics, Pearson's chi-square test, Wilcoxon's rank-sum test and stepwise generalized linear model (GLM) were performed with significance set at P < 0.05. RESULT: Most participants' (91.61%) follow-up appointments were suspended. The emergency rate and emergency treatment requirements were not different between the fixed appliance (FA) and clear aligner (CA) groups. Patients who reported emergencies (P < 0.01) in the FA group (P < 0.05) and some emergencies in the FA (P < 0.05) suffered worse pain and disability. More FA participants preferred alternative appliances (P < 0.05) due to pain and disability (P < 0.05). CONCLUSION: FA patients' emergencies caused worse pain and disability when orthodontic appointments were suspended. Pain and disability were not the causes of emergency treatment requirements. The CA group seemed to show a tendency towards orthodontic appliance preference, which was an ideal modality to weather the epidemic, combined with telemedicine.


Asunto(s)
COVID-19 , Humanos , Pandemias , Urgencias Médicas , Aparatos Ortodóncicos , Dolor Facial/etiología , Dolor Facial/terapia
5.
BMC Oral Health ; 23(1): 214, 2023 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-37060002

RESUMEN

BACKGROUND: The purpose of this study was to compare the perception of upper dental midline deviation on the attractiveness of a smile among raters from different ethnicities, professions, genders, and ages and measure to what extent the presence or absence of the associated smiling structures influence the raters' evaluations. METHODS: A male subject (26 years of age) with adequate smile characteristics was selected by 3 experienced orthodontists, and 561 raters from 2 different ethnic groups (281 Chinese raters and 280 Black raters) rated the subject's smile after the subject's upper dental midline was digitally altered from 0 to 5 mm using a 5-point Likert scale on 12 smile photographs divided into two groups: group 1, in the presence of smile related structures, two-thirds of the nose, lips, and chin (NLC), and group 2, in the absence of smile related structures, the lips only (L). RESULTS: There were statistically significant differences (p < 0.05) between the two ethnicities, in 2 mm and 4 mm in-group NLC and 5 mm in-group L, as well as the raters' profession to each midline shift of both groups (NLC) and (L) for both ethnicities except for 0 mm. Regarding the role of associated smile structures, the smile photos were observed in the presence of smile-associated structures, and in its absence (NLC × L), statistically significant differences (p < 0.05) were found when the deviation was 5 mm among the Chinese raters; in 1 mm, and 4 mm among the Black raters. Among different genders, statistical differences were only reported (p < 0.05) for Chinese raters for 5 mm in NLC, while statistical differences were observed for 2 mm and 3 mm in NLC for Black raters. For age categories, differences were observed (p < 0.05) for 4 mm, 5 mm in NLC and 4 mm, and 5 mm in L for Chinese raters, while 5 mm in NLC and 1 mm in L for Black raters. CONCLUSION: Perception of the upper dental midline deviations was influenced by the factors of ethnicity, profession, presence or absence of smile-associated structures, as well as the gender and age of the raters.


Asunto(s)
Población Negra , Pueblos del Este de Asia , Estética Dental , Sonrisa , Femenino , Humanos , Masculino , Actitud del Personal de Salud , Pueblos del Este de Asia/psicología , Estética Dental/psicología , Incisivo/anatomía & histología , Percepción , Sonrisa/psicología , Adulto , Población Negra/psicología
6.
Macromol Rapid Commun ; 43(19): e2200272, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35640021

RESUMEN

Physically cross-linked hydrogels have great potential for tissue engineering because of their excellent biocompatibility and easy fabrication. However, physical cross-linking points are typically weaker compared to chemical ones and therefore cannot form robust hydrogels with excellent water stability, which greatly hinder their further applications. In this work, a novel hydrogel with high stiffness and outstanding antiswelling performance cross-linked by hydrophobic polymer chains entanglements is reported. The hydrophobic polymer polyimide (PI) is mixed with the hydrophilic polymer poly-(vinyl pyrrolidone) (PVP) to form cross-linking points between the chains. At the equilibrium swelling state, tensile modulus of the hydrogel can be up to 22.57 MPa (higher than most existing hydrogels) and the equilibrium water swelling ratio (ESR) can be as low as 125.0%. By decreasing the PI mass ratio, tensile modulus and ESR of the hydrogel can be tuned in a wide range from 22.57 to 0.005 MPa and 125.0% to 765.6%, respectively. Using PVP/PI solutions as inks, uniform structures and multi-material structures are fabricated having mechanical properties close to cartilage through a direct ink writing 3D printing platform. This current work demonstrates that entangled PVP/PI hydrogels have excellent tailoring capabilities and are promising candidates for tissue engineering applications.


Asunto(s)
Materiales Biocompatibles , Hidrogeles , Materiales Biocompatibles/química , Hidrogeles/química , Polímeros , Pirrolidinonas , Ingeniería de Tejidos , Agua
7.
Mikrochim Acta ; 189(3): 125, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35229221

RESUMEN

A novel electrochemical sensor is reported for the detection of the antiviral drug favipiravir based on the core-shell nanocomposite of flower-like molybdenum disulfide (MoS2) nanospheres and molecularly imprinted polymers (MIPs). The MoS2@MIP core-shell nanocomposite was prepared via the electrodeposition of a MIP layer on the MoS2 modified electrode, using o-phenylenediamine as the monomer and favipiravir as the template. The selective binding of target favipiravir at the MoS2@MIP core-shell nanocomposite produced a redox signal in a concentration dependent manner, which was used for the quantitative analysis. The preparation process of the MoS2@MIP core-shell nanocomposite was optimized. Under the optimal conditions, the sensor exhibited a wide linear response range of 0.01 ~ 100 nM (1.57*10-6 ~ 1.57*10-2 µg mL-1) and a low detection limit of 0.002 nM (3.14*10-7 µg mL-1). Application of the sensor was demonstrated by detecting favipiravir in a minimum amount of 10 µL biological samples (urine and plasma). Satisfied results in the recovery tests indicated a high potential of favipiravir monitoring in infectious COVID-19 samples.


Asunto(s)
Amidas/análisis , Antivirales/análisis , Disulfuros/química , Polímeros Impresos Molecularmente/química , Molibdeno/química , Nanocompuestos/química , Nanosferas/química , Pirazinas/análisis , Amidas/sangre , Amidas/uso terapéutico , Amidas/orina , Antivirales/sangre , Antivirales/uso terapéutico , Antivirales/orina , COVID-19/virología , Técnicas Electroquímicas/métodos , Humanos , Límite de Detección , Oxidación-Reducción , Pirazinas/sangre , Pirazinas/uso terapéutico , Pirazinas/orina , Reproducibilidad de los Resultados , SARS-CoV-2/aislamiento & purificación , Tratamiento Farmacológico de COVID-19
8.
Macromol Rapid Commun ; 41(15): e2000295, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32638470

RESUMEN

A method is reported for making hollow channels within hydrogels decorated with cell-adhesion peptides exclusively at the channel surface. Sacrificial fibers of different diameters are used to introduce channels within poly(ethylene glycol) hydrogels crosslinked with maleimide-thiol chemistry, which are backfilled with a cysteine-containing peptide solution which is conjugated to the lumen with good spatial efficiency. This allows for peptide patterning in only the areas of the hydrogel where they are needed when used as cell-guides, reducing the amount of required peptide 20-fold when compared to bulk functionalization. The power of this approach is highlighted by successfully using these patterned hydrogels without active perfusion to guide fibroblasts and olfactory ensheathing cells-the latter having unique potential in neural repair therapies.


Asunto(s)
Adhesión Celular , Técnicas de Cultivo de Célula/métodos , Hidrogeles/química , Péptidos/química , Polietilenglicoles/química , Impresión Tridimensional , Animales , Proliferación Celular , Supervivencia Celular , Hidrogeles/síntesis química , Maleimidas/química , Ratones , Microscopía Fluorescente , Células 3T3 NIH , Compuestos de Sulfhidrilo/química
9.
J Gastroenterol Hepatol ; 34(9): 1563-1570, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30597598

RESUMEN

BACKGROUND AND AIM: Salivary characteristics are altered in gastrointestinal diseases and related to oral taste disorder. However, specific salivary biochemical characteristics and their relationships with oral taste disturbances in chronic non-atrophy gastritis (CNAG) remain uncertain. METHODS: Seventy patients with CNAG and 70 subjects in healthy control group (HCG) were enrolled in our study. The levels of salivary flow rate (SFR), pH, salivary α-amylase (sAA) activity, total protein density (TPD), chloride concentration, and calcium concentration were determined before and after citric acid stimulation and compared between CNAG with and without oral taste disturbances. RESULTS: Average body mass index (BMI) of CNAG (17.75 ± 2.08) was lower than that of HCG (21.96 ± 1.72, P < 0.01). Compared with HCG, CNAG showed increased TPD and calcium concentration but decreased SFR both before and after acid stimulation (P < 0.01), as well as reduced sAA and salivary chloride responses to acid stimulation (P < 0.01). Compared with CNAG with normal BMI (24.29%, 17/70), sAA activity response to acid stimulation was reduced in those with low BMI (75.71%, 53/70, P < 0.05). Under resting condition, CNAG with dry mouth (55.71%, 39/70) showed increased SFR and decreased TPD (P < 0.05), as compared with CNAG without dry mouth (44.29%, 31/70). Compared with CNAG without bitter taste (57.14%, 40/70), pH was decreased in those with bitter taste (42.86%, 30/70) under both resting and stimulated conditions (P < 0.05). CONCLUSION: Decreased sAA activity may reflect malnutrition state and be one potential marker of poor digestion, decreased salivary pH may contribute to bitter taste perception, and reduced TPD might be a cause of dry mouth in CNAG.


Asunto(s)
Ácido Cítrico/administración & dosificación , Gastritis/metabolismo , Saliva/metabolismo , Salivación , Adulto , Biomarcadores/metabolismo , Estudios de Casos y Controles , Enfermedad Crónica , Estudios Transversales , Digestión , Femenino , Gastritis/diagnóstico , Gastritis/fisiopatología , Humanos , Concentración de Iones de Hidrógeno , Masculino , Persona de Mediana Edad , Proteínas/metabolismo , alfa-Amilasas Salivales/metabolismo , Gusto , Xerostomía/metabolismo , Xerostomía/fisiopatología
10.
Planta ; 247(5): 1077-1087, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29350280

RESUMEN

MAIN CONCLUSION: Six types of lignin-carbohydrate complex (LCC) fractions were isolated from Eucalyptus. The acidic dioxane treatment applied significantly improved the yield of LCCs. The extraction conditions had a limited impact on the LCC structures and linkages. Characterization of the lignin-carbohydrate complex (LCC) structures and linkages promises to offer insight on plant cell wall chemistry. In this case, Eucalyptus LCCs were extracted by aqueous dioxane, and then precipitated sequentially by 70% ethanol, 100% ethanol, and acidic water (pH = 2). The composition and structure of the six LCC fractions obtained by selective precipitation were investigated by sugar analysis, molecular weight determination, and 2D HSQC NMR. It was found that the acidic (0.05-M HCl) dioxane treatment significantly improved the yield of LCCs (66.4% based on Klason lignin), which was higher than the neutral aqueous dioxane extraction, and the extraction condition showed limited impact on the LCC structures and linkages. In the fractionation process, the low-molecular-weight LCCs containing a high content of carbohydrates (60.3-63.2%) were first precipitated by 70% ethanol from the extractable solution. The phenyl glycoside (PhGlc) bonds (13.0-17.0 per 100Ar) and highly acetylated xylans were observed in the fractions recovered by the precipitation with 100% ethanol. On the other hand, such xylan-rich LCCs exhibited the highest frequency of ß-O-4 linkages. The benzyl ether (BE) bonds were only detected in the fractions obtained by acidic water precipitation.


Asunto(s)
Carbohidratos/aislamiento & purificación , Eucalyptus/metabolismo , Lignina/aislamiento & purificación , Metabolismo de los Hidratos de Carbono , Carbohidratos/química , Precipitación Química , Dioxanos/uso terapéutico , Lignina/química , Lignina/metabolismo , Espectroscopía de Resonancia Magnética , Peso Molecular
11.
Macromol Rapid Commun ; 39(4)2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29171681

RESUMEN

In this study, a novel hydrogel patterning approach using 3D covalent transfer stamping from a fugitive ink is introduced. A model transfer molecule (7-diethylamino-3-(4'maleimidylphenyl)-4-methylcoumarin (CPM)) is absorbed into a 3D fugitive ink stamp made from poly(caprolactone), and then encapsulated in a poly(ethylene glycol) hydrogel. As the CPM diffuses from the fugitive ink to the curing hydrogel it is selectively covalently bound at the boundary of the ink and the hydrogel. Removal of the fugitive ink by solvent exchange leads to a negative copy of interconnected channels patterned with the localized transfer of the molecules at the hydrogel interface. The results suggest that small molecules can be patterned in porous hydrogels in a spatially controllable manner and that the transferred amount can be tuned.


Asunto(s)
Cumarinas/química , Hidrogeles/química , Polietilenglicoles/química , Solventes/química , Cumarinas/síntesis química , Hidrogeles/síntesis química , Tinta , Poliésteres/química , Propiedades de Superficie
12.
Biomacromolecules ; 18(3): 865-876, 2017 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-28240872

RESUMEN

To alleviate the hemorrhagic side effect of thrombolysis therapy, a thrombus targeted drug delivery system based on the specific affinity of Annexin V to phosphatidylserine exposed on the membrane surface of activated platelet was developed. The amphiphilic and biodegradable biomaterial, polycaprolactone-block-poly(2-(dimethylamino)ethyl methacrylate)-block-poly(2-hydroxyethyl methacrylate) (PCL-b-PDMAEMA-b-PHEMA (PCDH)) triblock polymer, was synthesized via ring opening polymerization (ROP) and atom transfer radical polymerization (ATRP) to use as the nanocarriers of thrombolytic drug. In order to conjugate Annexin V to the polymer, PCDH was modified by succinic anhydride via ring-opening reaction to introduce the carboxyl group (PCDH-COOH). After preparation of PCDH/PCDH-COOH (9/1, m/m) mixed micelles, Annexin V was coupled with the micelles using carbodiimide chemistry. The blood clot lysis assay in vitro confirmed that lumbrokinase-loaded targeted micelles (LKTM) had stronger thrombolysis potency than free lumbrokinase (LK) and LK-loaded nontargeted micelles (LKM, P < 0.05). In vivo thrombolytic assay, multispectral, optoacoustic tomography (MSOT) was used to assess the target ability of LKTM. The results of MSOT images indicated the fluorescence intensity of the LKTM group located in the blood clot position were significantly stronger than the LKM group. A 5 mm of carotid artery containing blood clot was cut out 24 h later after administration to assess the degree of thrombolysis. The results of thrombolytic assay in vivo were consistent with the assay in vitro, which the differences between LK, LKM, and LKTM groups were both statistically significant. All the results of thrombolysis assays above proved that the capacity of thrombolysis in the LKTM group was optimal. It suggested that Annexin V-conjugated micelles will be a potential drug delivery system for targeted thrombolysis.


Asunto(s)
Anexina A5/química , Sistemas de Liberación de Medicamentos , Micelas , Terapia Trombolítica , Animales , Materiales Biocompatibles/química , Células Cultivadas , Metacrilatos/química , Ratones , Nanopartículas/química , Nylons/química , Tamaño de la Partícula , Poliésteres/química , Polimerizacion , Trombosis/tratamiento farmacológico
13.
Neuro Endocrinol Lett ; 37(4): 265-268, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27857041

RESUMEN

We report an 8-year-old boy diagnosed with both CMT1 and narcolepsy, which were not reported simultaneously presenting in one person. The boy presented with a history of increased suddenly falling frequency and excessive daytime sleepiness for 3 months. CMT1 was diagnosed by electrophysiology and genetic testing. Narcolepsy had not been diagnosed until the frequently falling caused by sudden and transient episodes of legs weakness triggered by emotion was found. Multiple sleep latency test showed multiple sleep onset REM periods with reduced sleep latency. When CMT1 and narcolepsy were coexist in an individual, the latter might be overlooked. Cataplexy caused by narcolepsy might be disregard as distal muscle weakness of CMT1. The daytime sleepiness might also be ignored. Therefore, we recommend that patients with sleep disorders should be queried about the symptoms of narcolepsy.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/complicaciones , Narcolepsia/complicaciones , Enfermedad de Charcot-Marie-Tooth/genética , Enfermedad de Charcot-Marie-Tooth/fisiopatología , Niño , Humanos , Masculino , Proteínas de la Mielina/genética , Narcolepsia/diagnóstico , Conducción Nerviosa , Polisomnografía
14.
Mol Pharm ; 12(3): 769-82, 2015 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-25625539

RESUMEN

The design of nanoscale drug delivery systems for the targeted codelivery of multiple therapeutic drugs still remains a formidable challenge (ACS Nano, 2013, 7, 9558-9570; ACS Nano, 2013, 7, 9518-9525). In this article, both mitomycin C (MMC) and methotrexate (MTX) loaded DSPE-PEG micelles (MTX-M-MMC) were prepared by self-assembly using the dialysis technique, in which MMC-soybean phosphatidylcholine complex (drug-phospholipid complex) was encapsulated within MTX-functionalized DSPE-PEG micelles. MTX-M-MMC could coordinate an early phase active targeting effect with a late-phase synergistic anticancer effect and enable a multiple-responsive controlled release of both drugs (MMC was released in a pH-dependent pattern, while MTX was released in a protease-dependent pattern). Furthermore, MTX-M-MMC could codeliver both drugs to significantly enhance the cellular uptake, intracellular delivery, cytotoxicity, and apoptosis in vitro and improve the tumor accumulation and penetration and anticancer effect in vivo compared with either both free drugs treatment or individual free drug treatment. To our knowledge, this work provided the first example of the systemically administrated, orthogonally functionalized, and self-assisted nanoscale micelles for targeted combination cancer chemotherapy. The highly convergent therapeutic strategy opened the door to more simplified, efficient, and flexible nanoscale drug delivery systems.


Asunto(s)
Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos , Metotrexato/administración & dosificación , Mitomicina/administración & dosificación , Animales , Biofarmacia , Portadores de Fármacos/química , Sinergismo Farmacológico , Femenino , Células HeLa , Humanos , Metotrexato/farmacocinética , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Micelas , Mitomicina/farmacocinética , Nanocápsulas/química , Nanotecnología , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Fosfatidiletanolaminas/química , Polietilenglicoles/química , Ratas , Ratas Sprague-Dawley , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 32(2): 493-6, 2015 Apr.
Artículo en Zh | MEDLINE | ID: mdl-26211279

RESUMEN

Dental composite resin is a kind of material which has been widely used in dental restoration. Research has found that the influence of residual monomer on the material mechanical, chemical and biological properties cannot be ignored. This paper elaborates these harms of residual monomers. The effects of resin matrix, inorganic filler and initiating system, illumination, secondarily treatment on the degree of conversion were also analyzed. The paper also discusses the effective measures to increase the conversion, and offers theoretical basis for the clinical application and development of composite resin.


Asunto(s)
Resinas Acrílicas , Resinas Compuestas , Poliuretanos , Humanos , Luz , Polímeros
16.
Molecules ; 19(7): 9838-49, 2014 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-25006789

RESUMEN

The immobilized thermophilic esterase from Archaeoglobus fulgidus was successfully constructed through the glutaraldehyde-mediated covalent coupling after its physical adsorption on a hydrophobic macroporous resin, Sepabeads EC-OD. Through 0.05% glutaraldehyde treatment, the prevention of enzyme leaching and the maintenance of catalytic activity could be simultaneously realized. Using the enzymatic ring-opening polymerization of ε-caprolactone as a model, effects of organic solvents and reaction temperature on the monomer conversion and product molecular weight were systematically investigated. After the optimization of reaction conditions, products were obtained with 100% monomer conversion and Mn values lower than 1010 g/mol. Furthermore, the cross­linked immobilized thermophilic esterase exhibited an excellent operational stability, with monomer conversion values exceeding 90% over the course of 12 batch reactions, still more than 80% after 16 batch reactions.


Asunto(s)
Enzimas Inmovilizadas/química , Esterasas/química , Poliésteres/síntesis química , Reactivos de Enlaces Cruzados/química , Estabilidad de Enzimas , Glutaral/química , Cinética , Polimerizacion , Temperatura
17.
Chemosphere ; 358: 142133, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38670511

RESUMEN

The impact of Fenton-ultrasound treatment on the production of polyphenols and humic acid (HA) during corn stalk composting was investigated by analyzing the potential for microbial assimilation of polysaccharides in corn stalks to generate polyphenols using a13C-glucose tracer. The results showed that Fenton-ultrasound treatment promoted the decomposition of lignocellulose and increased the HA content, degree of polymerization (DP), and humification index (HI). The primary factor could be attributed to Fenton-ultrasound treatment-induced enhanced the abundance of lignocellulose-degrading microorganisms, as Firmicutes, Actinobacteria phylum and Aspergillis genus, which serve as the primary driving forces behind polyphenol and HA formation. Additionally, the utilization of a13C isotope tracer revealed that corn stalk polysaccharide decomposition products can be assimilated by microbes and subsequently secrete polyphenolic compounds. This study highlights the potential of microbial activity to generate phenolic compounds, offering a theoretical basis for increasing polyphenol production and promoting HA formation during composting.


Asunto(s)
Compostaje , Sustancias Húmicas , Polifenoles , Zea mays , Polifenoles/metabolismo , Polifenoles/química , Lignina/química , Lignina/metabolismo , Peróxido de Hidrógeno/metabolismo , Hierro/química , Hierro/metabolismo , Ondas Ultrasónicas , Microbiología del Suelo , Biodegradación Ambiental
18.
Front Oral Health ; 5: 1369494, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38774040

RESUMEN

Objectives: This article reports on four rare cases involving multiple trauma-induced adjacent missing anterior teeth in the maxillary or mandibular region. These cases were successfully treated using a 4-axial implant-based alternative insert and an immediate loading protocol. Material and methods: This series of cases was summarized by retrospective study that 4 patients who received a total of 20 immediately loaded implants. These patients had suffered from trauma-induced loss of 8-9 adjacent anterior teeth. The 4-axial-implants were inserted with the assistance of digital pioneer drill guides. The surgical procedure involved alveolar bone trimming or ultrasonic osteotomy, eliminating the need for traditional large-area bone augmentation. Pre- and post-operative CBCT was matched using DTX Studio Implant software, the deviation of implant between actual position and preoperative design was measured and compared using SPSS software package. Results: The average follow-up duration 48 months after implant prostheses, the cumulative retention rate of the implants was 100%, the marginal bone loss averaged 0.53 mm (SD 0.15 mm), and buccal plate bone loss averaged 0.62 mm (SD 0.41 mm). Conclusions: This retrospective clinical report demonstrates the successful treatment of several patients with multiple adjacent maxillary or mandibular anterior teeth using four implant-supported screws to fix the frame and employing immediate loading. The approach resulted in long-term stable clinical outcomes. Moreover, the method not only shortens the period of edentulism but also facilitates easy disassembly, maintenance, and cleaning. Consequently, it emerges as a highly favorable clinical option for patients suffering from extensive tooth loss.

19.
Sheng Wu Gong Cheng Xue Bao ; 40(1): 226-238, 2024 Jan 25.
Artículo en Zh | MEDLINE | ID: mdl-38258643

RESUMEN

TCP family as plant specific transcription factor, plays an important role in different aspects of plant development. In order to screen TCP family members in tobacco, the homologous sequences of tobacco and Arabidopsis TCP family were identified by genome-wide homologous alignment. The physicochemical properties, phylogenetic relationships and cis-acting elements were analyzed by bioinformatics. The homologous genes of AtTCP3/AtTCP4 were screened, and RT-qPCR was used to detect the changes of gene expression upon 20% PEG6000 treatment. The results show that tobacco contains 63 TCP family members. Their amino acid sequence length ranged from 89 aa to 596 aa, and their protein hydropathicity grand average of hydropathicity (GRAVY) ranged from -1.147 to 0.125. The isoelectric point (pI) ranges from 4.42 to 9.94, the number of introns is 0 to 3, and the subcellular location is all located in the nucleus. The results of conserved domain and phylogenetic relationship analysis showed that the tobacco TCP family can be divided into PCF, CIN and CYC/TB1 subfamilies, and each subfamily has a stable sequence. The results of cis-acting elements in gene promoter region showed that TCP family genes contain low docile acting elements (LTR) and a variety of stress and metabolic regulation related elements (MYB, MYC). Analysis of gene expression patterns showed that AtTCP3/AtTCP4 homologous genes (NtTCP6, NtTCP28, NtTCP30, NtTCP33, NtTCP42, NtTCP57, NtTCP63) accounted for 20% PEG6000 treatment significantly up-regulated/down-regulated expression, and NtTCP30 and NtTCP57 genes were selected as candidate genes in response to drought. The results of this study analyzed the TCP family in the tobacco genome and provided candidate genes for the study of drought-resistance gene function and variety breeding in tobacco.


Asunto(s)
Arabidopsis , Nicotiana , Nicotiana/genética , Filogenia , Fitomejoramiento , Secuencia de Aminoácidos , Polietilenglicoles
20.
J Mater Chem B ; 12(12): 3092-3102, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38445378

RESUMEN

Conductive hydrogel sensors have attracted attention for use in human motion monitoring detection, but integrating excellent biocompatibility, mechanical, self-adhesive, and self-healing properties, and high sensitivity into a hydrogel remains a challenge. In this work, a novel multifunctional conductive particle was designed and added to a polyacrylamide (PAM) matrix to prepare the hydrogel. It is worth noting that with the addition of polydopamine@poly(3,4-ethylenedioxythiophene) (PDA@PEDOT), the PAM/PDA@PEDOT hydrogel (PAPP hydrogel) showed excellent mechanical properties and high adhesion strength on different substrate surfaces. Meanwhile, the PAPP hydrogel shows outstanding self-healing properties, the mechanical properties of PAPP hydrogel broken from the middle recovered 92% tensile strength and 95% elongation at break after 12 h, respectively. Furthermore, assembled as strain wireless sensors, the PAPP sensor displays high sensitivity, where the gauge factor (GF) is 2.82, which can be used to accurately detect human facial micro-expressions and movements. Overall, the PAPP hydrogel with excellent mechanical, self-adhesive, and self-healing properties, and high sensitivity, demonstrated promise for use in wearable devices and bionic skins.


Asunto(s)
Biónica , Cementos de Resina , Humanos , Nanogeles , Conductividad Eléctrica , Hidrogeles
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