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1.
J Orthop Surg Res ; 18(1): 913, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38031095

RESUMEN

BACKGROUND: Our experience with the surgical flip-dislocation of the bicolumnar (SFDB) approach for type AO 13C3 humeral fractures indicates that this surgical approach can be performed safely and effectively in appropriately selected patients. We aimed to evaluate the clinical outcomes of the SFDB approach without olecranon osteotomy (OO) for type AO 13C3 distal humeral fractures. METHODS: We retrospectively reviewed 65 cases of type AO 13C3 distal humeral fractures treated between April 2008 and July 2018; 33 patients were treated with the SFDB approach, and the remaining were treated with OO. Propensity score matching was used to control for sex, age, and the American Society of Anesthesiology score. Elbow pain, range of motion, stability, and function were assessed using the Mayo Elbow Performance Index (MEPI) and the Disabilities of the Arm, Shoulder, and Hand questionnaire. Clinical complications, reoperation rates, and radiographic results were compared between the groups. RESULTS: Operative time and blood loss were significantly lower in the SFDB group than in the OO group (P = 0.001, P = 0.002, respectively). At the final follow-up, the mean postoperative MEPI did not significantly differ between the groups (P = 0.628). According to Morrey's criteria, a typical functional range of elbow motion was achieved in 12 and 15 patients in the SFDB and OO groups, respectively. CONCLUSIONS: The SFDB approach achieves superior exposure of the articular surface without injury to the extensor mechanism in type 13C3 articular surface fracture treatment. This approach also results in good early functional recovery and clinical outcomes, with a low risk of complications.


Asunto(s)
Articulación del Codo , Fracturas Humerales Distales , Fracturas del Húmero , Luxaciones Articulares , Olécranon , Humanos , Olécranon/cirugía , Estudios de Cohortes , Estudios Retrospectivos , Resultado del Tratamiento , Fijación Interna de Fracturas/métodos , Articulación del Codo/diagnóstico por imagen , Articulación del Codo/cirugía , Fracturas del Húmero/diagnóstico por imagen , Fracturas del Húmero/cirugía , Osteotomía/métodos , Rango del Movimiento Articular , Luxaciones Articulares/etiología
2.
Inorg Chem ; 62(13): 5105-5113, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-36933227

RESUMEN

The introduction of a secondary interaction is an efficient strategy to modulate transition-metal-catalyzed ethylene (co)polymerization. In this contribution, O-donor groups were suspended on amine-imine ligands to synthesize a series of nickel complexes. By adjusting the interaction between the nickel metal center and the O-donor group on the ligands, these nickel complexes exhibited high activities for ethylene polymerization (up to 3.48 × 106 gPE·molNi-1·h-1) with high molecular weight up to 5.59 × 105 g·mol-1 and produced good polyethylene elastomers (strain recovery (SR) = 69-81%). In addition, these nickel complexes can catalyze the copolymerization of ethylene with vinyl acetic acid, 6-chloro-1-hexene, 10-undecylenic, 10-undecenoic acid, and 10-undecylenic alcohol to prepare the functionalized polyolefins.

3.
Molecules ; 27(10)2022 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-35630591

RESUMEN

We report that the pincer nickel complexes display prostate cancer antitumor properties through inhibition of cell proliferation. Notably, they display better antitumor properties than cisplatin. Mechanistic studies reveal that these pincer nickel complexes trigger cell apoptosis, most likely due to cell cycle arrest. Interestingly, these complexes also inhibit androgen receptor (AR) and prostate-specific antigen (PSA) signaling, which are critical for prostate cancer survival and progression. Our study reveals a novel function of pincer nickel complexes as potential therapeutic drugs in prostate cancer.


Asunto(s)
Antineoplásicos , Neoplasias de la Próstata , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Humanos , Masculino , Níquel , Pelvis/patología , Neoplasias de la Próstata/patología
4.
J Biomed Mater Res B Appl Biomater ; 110(9): 2100-2109, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35441415

RESUMEN

Peripheral nerve injury (PNI) exists widely and seriously affects patients' daily lives. However, the effect of nerve repair is still limited, and only 50% of patients can recover useful functions. To overcome these obstacles, collagen-coated poly(lactic-co-glycolic acid) (PLGA) conduits loaded with CBD-IGF-1 were designed and tested in vitro and in vivo. The physical characterization of the conduit was tested by scanning electron microscopy, and the static water contact angle, release rate, and nerve regeneration ability of the conduit were verified in a rat sciatic nerve injury model. The results showed that the PLGA/col/CBD-IGF-1 conduit had a rough surface and good hydrophilicity. CBD-IGF-1 could be released slowly from the PLGA/col/CBD-IGF-1 conduit. In the in vivo experiment, gait analysis and electrophysiological evaluation showed that the sciatic functional index and electrophysiological parameters were best in the group treated with the PLGA/col/CBD-IGF-1 conduit. The pathological examination results for the sciatic nerve and gastrocnemius muscle in the group treated with the PLGA/col/CBD-IGF-1 conduit were better than those in the other three groups. In short, this study demonstrated the beneficial effects of CBD-IGF-1 in nerve regeneration. The PLGA/col/CBD-IGF-1 conduit has therapeutic potential for use in the treatment of PNI.


Asunto(s)
Traumatismos de los Nervios Periféricos , Ácido Poliglicólico , Animales , Colágeno/farmacología , Glicoles/farmacología , Factor I del Crecimiento Similar a la Insulina/farmacología , Ácido Láctico/química , Regeneración Nerviosa , Traumatismos de los Nervios Periféricos/terapia , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacología , Ratas , Nervio Ciático/fisiología
5.
J Agric Food Chem ; 70(2): 615-625, 2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-35005957

RESUMEN

A total of 11 new (1-11) and 2 known (12 and 13) ent-kaurane diterpene derivatives were identified from the roasted beans of Coffea cultivar S288. Their structures were established by extensive spectroscopic analysis, including one- and two-dimensional nuclear magnetic resonance (heteronuclear single-quantum correlation, heteronuclear multiple-bond correlation, correlation spectroscopy, and rotating-frame Overhauser enhancement spectroscopy), high-resolution electrospray ionization mass spectrometry, and X-ray analyses. Cafespirone acid A (1) represents the first example of diterpene featuring a spirocyclic skeleton constructed from a 6/6/5 tricyclic system. Cafeane acid A (2) possesses a 6/6/6/5 tetracyclic system as a result of the C/D ring rearrangement. Furthermore, compounds 1-12 were evaluated for their α-glucosidase inhibitory activity. The results showed that compounds 2, 4, 5, 6, 7, 10, and 11 had a moderate inhibitory effect on α-glucosidase, and half-maximal inhibitory concentration values of compounds 4, 6, 7, and 10 were 18.76 ± 1.46, 4.88 ± 0.03, 12.35 ± 0.91, and 12.64 ± 0.59 µM, respectively, compared to the positive control acarbose (60.71 ± 16.45 µM). Additionally, the molecular docking experiments showed that the carbonyl group at C-19 of compounds 4, 6, and 7 formed strong hydrogen bonds with ARG315, which may make them have moderate inhibitory activity.


Asunto(s)
Coffea , Diterpenos de Tipo Kaurano , Diterpenos , Coffea/metabolismo , Café , Espectroscopía de Resonancia Magnética , Simulación del Acoplamiento Molecular , Estructura Molecular , alfa-Glucosidasas/metabolismo
6.
World J Clin Cases ; 9(25): 7478-7483, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34616815

RESUMEN

BACKGROUND: Forearm crisscross injury is rare in children; there is no relevant literature so far. Surgeons lack experience and knowledge in treating this type of crisscross injury. We report a case of forearm crisscross injury in a child for the first time and analyze its mechanism. CASE SUMMARY: An 8-year-old boy experienced pain in his left forearm when he accidentally fell while skateboarding. Physical examination revealed swelling and deformity of the left forearm. We performed imaging and the results revealed left radial head dislocation, left distal radial epiphyseal separation from the shaft, and interruption of the continuity of the dorsal cortex of the left distal ulna. Anteroposterior and lateral X-ray films showed that the radius and ulna were crisscrossed. A diagnosis of superior radioulnar joint dislocation, left distal radial epiphyseal injury, and left distal ulnar fracture was made. After unsuccessful manual reduction, we adopted a minimally invasive procedure and succeeded. After a 14-wk period of follow-up, the patient had good left upper limb function, no complaints of pain or limited range of motion, and good follow-up results. CONCLUSION: This is the first report of a child with a forearm crisscross injury in which the mechanism and the differences from adult crisscross injury are analyzed. Minimally invasive surgery with intramedullary fixation can achieve a good therapeutic effect. This case provides a reference for the treatment of similar patients in the future.

7.
J Virol Methods ; 296: 114226, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34217779

RESUMEN

BACKGROUND: Clinical importance of commercially available quantitative HBV markers has not been fully investigated. OBJECTIVE: To choice and to evaluate clinically valuable HBV markers for predicting phases of natural history with chronic HBV infection. METHODS: 472 naïve patients with chronic HBV infection were enrolled, in which 21 and 220 were confirmed as HBeAg-positive inactive and active hepatitis (EPIH and EPAH), respectively, and 106 and 125 were confirmed as HBeAg-negative inactive and active hepatitis (ENIH and ENAH), respectively. HBsAg, HBcrAg and anti- HBc were measured using chemiluminescent immunoassay, and HBV DNA was measured using PCR-fluorescence probing assay. RESULTS: There were all statistical differences in medians of HBsAg, anti-HBc, HBcrAg and HBV DNA between EPIH and EPAH and between ENIH and ENAH (all P < 0.01). According to binary logistic stepwise regressions, HBsAg and anti-HBc were preferred variables for predicting EPAH, and HBcrAg and HBV DNA were preferred variables for predicting ENAH. Based on normalization for coefficients of preferred variables entering regression equations, a handy model of MEPAH for predicting EPAH and of MENAH for predicting ENAH was constructed, respectively. Area under receiver operating characteristic curves of MEPAH and MENAH for predicting EPAH and ENAH were 0.882 and 0.931, respectively. With standard of MEPAH ≤ 5.997 and MENAH > 10.535, sensitivity or specificity of which for predicting EPAH and ENAH were about 81.0 % and 87.0 %, respectively. CONCLUSION: HBsAg and anti-HBc for predicting EPAH and HBcrAg and HBV DNA for predicting ENAH are dependable markers; MEPAH for predicting EPAH and MENAH for predicting ENAH have very good performance.


Asunto(s)
Biomarcadores/sangre , Hepatitis B Crónica/diagnóstico , ADN Viral/sangre , Anticuerpos contra la Hepatitis B/sangre , Antígenos del Núcleo de la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/sangre , Humanos
8.
Food Chem ; 353: 129471, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33730668

RESUMEN

Defatted walnut meal protein was hydrolyzed using alcalase to yield tyrosinase inhibitory peptides. After separation by ultrafiltration and Sephadex G-25, the fraction with the highest tyrosinase inhibitory activity was identified using liquid chromatography-tandem mass spectrometry and 606 peptides were obtained. Then, molecular docking was used to screen for tyrosinase inhibitory peptides and to clarify the theoretical interaction mechanism between the peptides and tyrosinase. A peptide with the sequence Phe-Pro-Tyr (FPY, MW: 425.2 Da) was identified and the synthesized peptide inhibited tyrosine monophenolase and diphenolase with IC50 values of 1.11 ± 0.05 and 3.22 ± 0.09 mM, respectively. The inhibition of tyrosinase by FPY was competitive and reversible. Good stability of FPY toward digestion was observed in an in vitro gastrointestinal digestion simulation experiment. These results indicated that FPY can be used as a potential tyrosinase inhibitor in the food, medicine, and cosmetics industries.


Asunto(s)
Juglans/metabolismo , Monofenol Monooxigenasa/antagonistas & inhibidores , Péptidos/química , Sitios de Unión , Digestión , Hidrólisis , Cinética , Simulación del Acoplamiento Molecular , Monofenol Monooxigenasa/metabolismo , Nueces/metabolismo , Péptidos/aislamiento & purificación , Péptidos/metabolismo , Extractos Vegetales/metabolismo
9.
J Org Chem ; 86(1): 947-958, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33351617

RESUMEN

A NaOH-mediated sustainable synthesis of functionalized quinoxalines is disclosed via redox condensation of o-nitroamines with diols and α-hydroxy ketones. Under optimized conditions, various o-nitroamines and alcohols are well tolerated to generate the desired products in 44-99% yields without transition metals and external redox additives.

10.
Ann Lab Med ; 39(1): 67-75, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30215232

RESUMEN

BACKGROUND: We examined changes in hepatitis B core-related antigen (HBcrAg) during the four sequential phases of chronic hepatitis B virus (HBV) infection: hepatitis B e antigen (HBeAg)-positive chronic infection (EPCI) and hepatitis (EPCH), followed by HBeAg-negative chronic infection (ENCI) and hepatitis (ENCH). We compared the performance of serum HBcrAg, hepatitis B surface antigen (HBsAg), and HBV DNA in predicting EPCH and ENCH. METHODS: We enrolled 492 consecutive patients: 49 with EPCI, 243 with EPCH, 101 with ENCI, and 99 with ENCH. HBcrAg was detected by chemiluminescent enzyme immunoassays. HBsAg and HBeAg were detected by chemiluminescent microparticle immunoassays. HBV DNA was detected by real-time PCR. Predictive performance of HBcrAg, HBsAg, and HBV DNA was evaluated using ROC curves. RESULTS: Areas under ROC curves (AUCs) of HBcrAg, HBsAg, and HBV DNA for predicting EPCH were 0.738, 0.812, and 0.717, respectively; optimal cutoffs were ≤1.43×105 kU/mL, ≤1.89×104 IU/mL, and ≤3.97×107 IU/mL, with sensitivities and specificities of 66.3% and 77.6%, 65.0% and 93.9%, and 60.5% and 79.6%, respectively. AUCs of HBcrAg, HBsAg, and HBV DNA for predicting ENCH were 0.887, 0.581, and 0.978, respectively; optimal cutoffs were >26.8 kU/mL, >2.29×10² IU/mL, and >8.75×10³ IU/mL, with sensitivities and specificities of 72.7% and 95.1%, 86.9% and 39.6%, and 89.9% and 92.1%, respectively. CONCLUSIONS: HBsAg and HBV DNA were the best predictors of EPCH and ENCH, respectively. HBcrAg is an important surrogate marker for predicting EPCH and ENCH.


Asunto(s)
ADN Viral/sangre , Antígenos del Núcleo de la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/metabolismo , Adolescente , Adulto , Anciano , Área Bajo la Curva , Femenino , Virus de la Hepatitis B/genética , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/virología , Humanos , Inmunoensayo , Mediciones Luminiscentes , Masculino , Persona de Mediana Edad , Curva ROC , Reacción en Cadena en Tiempo Real de la Polimerasa , Sensibilidad y Especificidad , Adulto Joven
11.
RSC Adv ; 8(6): 3250-3263, 2018 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-35541186

RESUMEN

Methanesulfonate (MSA-), found in substantial concentrations in the atmosphere, is expected to enhance aerosol nucleation and the growth of nanoparticles, but the details of methanesulfonate clusters are poorly understood. In this study, MSA- was chosen along with ammonia (NH3) or three common amines and water (H2O) to discuss the roles of ternary homogeneous nucleation and ion-induced nucleation in aerosol formation. We studied the structural characteristics and thermodynamics of the clusters using density functional theory at the PW91PW91/6-311++G(3df,3pd) level. The analysis of noncovalent interactions predicts that the amines can form more stable clusters with MSA- than NH3, in agreement with the results from structures and thermodynamics; however, the enhancement in stability for amines is not large enough to overcome the difference in the concentrations of NH3 and amines under typical atmospheric conditions. In addition, the favorable free energies of formation for the (MSA-)(NH3/amines)(H2O) n (n = 0-3) clusters at 298.15 K show that MSA- could contribute to the aerosol nucleation process with binding NH3/amines and H2O up to n = 3. There are strong temperature and humidity dependences for the formation of complexes; higher humidity and temperature promote the formation of larger hydrates. Finally, for the (MSA-)(NH3/amines)(H2O) n clusters, the evaporation rates were determined to further investigate the atmospheric implications.

12.
BMC Gastroenterol ; 17(1): 140, 2017 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-29202690

RESUMEN

BACKGROUND: The current clinical practice on chronic hepatitis B (CHB) requires better on-treatment monitoring of viral persistence. Quantified assays for hepatitis B surface antigen (HBsAg) and core-related antigen (HBcrAg) hold promise for further optimization of therapy. Here, we aimed to characterize HBcrAg during the natural course of CHB. METHODS: Four-hundred and forty four treatment naïve CHB patients, who all underwent liver histology examination, were enrolled in this cross-sectional study. Their HBV DNA, HBsAg, HBeAg and HBcrAg titres were quantified and analyzed in the context of four distinct clinical phases. Correlation of HBcrAg and HBsAg with other markers were performed. The relationship between liver and serum antigen levels were also assessed. RESULTS: HBcrAg, like HBsAg, exhibited high degree of correlation with HBV DNA. However, a more significant linear relationship was found between HBcrAg and HBeAg titre in immune tolerant (IT) and immune clearance (IC) phases, while in HBeAg negative hepatitis (ENH) group, HBV DNA is a major determinant of HBcrAg. Significant difference was observed in liver HBcAg score and HBcrAg level in both IT and IC phases whereas barely significant positive correlations between liver HBsAg score and HBsAg titre was documented. CONCLUSION: HBcrAg titre exhibited distinct correlative profile in a phase-specific manner. In addition, its level is well-related to the intrahepatic expression of core antigen. It has a considerable utility in monitoring and refining antiviral therapy.


Asunto(s)
Antígenos del Núcleo de la Hepatitis B/sangre , Hepatitis B Crónica/sangre , Adulto , Antivirales/uso terapéutico , Biomarcadores/sangre , Estudios Transversales , ADN Viral/sangre , Femenino , Hepatitis B/genética , Hepatitis B/inmunología , Antígenos del Núcleo de la Hepatitis B/metabolismo , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/virología , Humanos , Modelos Lineales , Hígado/metabolismo , Masculino , Carga Viral
13.
J Zhejiang Univ Sci B ; 18(8): 727-732, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28786249

RESUMEN

Obesity has been reported to be associated with many diseases. However, common obesity-induced biological processes have not been evaluated across these diseases. We identified genes associated with obesity and obesity-related diseases, and used them to construct protein‒protein interaction networks. We also analyzed gene ontology (GO) in those genes overlapping between obesity and disease. Our work identifies gene modules common to obesity and obesity-related diseases, which can provide a basis for understanding the process of how obesity induces disease.

14.
J Virol Methods ; 235: 92-98, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27230224

RESUMEN

The objective of this study was to evaluate the validities of serum hepatitis B core-related antigen (HBcrAg) for predicting the pathological status of liver tissues of chronic hepatitis B (CHB). A total of 205 Chinese patients with CHB, including 121 HBeAg-positive and 84 HBeAg-negative patients, were enrolled in this study. In HBeAg-positive patients, AUCs of serum HBcrAg for predicting severe necro-inflammation and advanced fibrosis were greater than 0.70; using serum HBcrAg<=4.81×10(4)kUmL(-1) and <=2.45×10(4)kUmL(-1) as cutoffs, the sensitivities, specificities, accuracies for predicting severe necro-inflammation and advanced fbrosis were 0.697, 0.716, 0.711 and 0.818, 0.778, 0.785, respectively. In HBeAg-negative patients, the AUCs of serum HBcrAg for predicting significant necro-inflammation and significant fibrosis were greater than 0.70; using serum HBcrAg>=1.70×10(2)kUmL(-1) and >=4.02kUmL(-1) as cutoffs, the sensitivities, specificities, accuracies for predicting significant necro-inflammation and significant fibrosis were 0.929, 0.964, 0.952 and 1.000, 1.000, 1.000, respectively. These results indicated favorable performances of serum HBcrAg for predicting severe necro-inflammation and advanced fibrosis in HBeAg-positive patients and significant necro-inflammation and significant fibrosis in negative patients.


Asunto(s)
Antígenos del Núcleo de la Hepatitis B/sangre , Hepatitis B Crónica/patología , Cirrosis Hepática/diagnóstico , Hígado/patología , Adolescente , Adulto , Anciano , ADN Viral/sangre , Femenino , Antígenos del Núcleo de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/virología , Humanos , Hígado/virología , Cirrosis Hepática/patología , Cirrosis Hepática/virología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Adulto Joven
15.
Acta Biomater ; 40: 153-161, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26969525

RESUMEN

UNLABELLED: A crosslinkable zwitterionic copolymer PMBT was coated onto the surfaces of polypropylene hollow fiber membrane (PP-HFM) oxygenator and its connecting tubes. The PMBT copolymer coating on the oxygenator circuit formed a cell outer membrane mimetic surface with excellent stability. The hemocompatibility of the PMBT copolymer coated PP-HFM oxygenator circuit was evaluated by animal extracorporeal circulation. The concentrations of clotting components fibrinogen and platelet in the blood were almost unchanged during the circulation through the PMBT copolymer coated oxygenator circuits. By contrast, the concentrations of fibrinogen and platelet were significantly reduced to 52% and 56% respectively in the uncoated oxygenator group due to adsorption and thrombogenesis of the blood during 2h circulation. Moreover, concentration of activation marker beta-thromboglobulin for platelet in the blood was remarkably lower in the PMBT group than the uncoated control group (p<0.01). All the results strongly supported that the hemocompatibility of the PP-HFM oxygenator circuit could be improved significantly by coating a stable and densely assembled zwitterionic polymer film. This simple, stable and highly effective cell membrane mimetic coating strategy may be applicable in developing advanced oxygenator systems and other artificial organs. STATEMENT OF SIGNIFICANCE: Although a number of studies have reported the fabrication of zwitterionic phosphorylcholine coated oxygenators to resist the adsorption and activation of blood components and eliminate heparin-induced thrombocytopenia, none of them have fabricated stable and densely assembled film, especially with crosslinkable amphiphilic random copolymer described in our manuscript. The novel features of our work include.


Asunto(s)
Plaquetas/metabolismo , Materiales Biocompatibles Revestidos/química , Membranas Artificiales , Oxigenadores de Membrana , Adhesividad Plaquetaria , Polipropilenos/química , Adsorción , Animales , Adhesión Celular , Perros , Masculino
16.
J Mater Chem B ; 3(11): 2350-2361, 2015 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-32262065

RESUMEN

The design and easy fabrication of biocompatible and antifouling coatings on different materials are extremely important for biotechnological and biomedical devices. Here we report a substrate-independent biomimetic modification strategy for fabricating a biocompatible and antifouling ultra-thin coating. Cell membrane antifouling phosphorylcholine (PC) and/or mussel adhesive catechol (c) groups are grafted at the amino-ends of an 8-armed poly(ethylene glycol). The PC groups are introduced by grafting a random copolymer bearing both PC and active ester groups. The modified 8-arm PEGs (PEG-2c-23PC, PEG-6c-23PC and PEG-8c) anchor themselves onto various substrates from aqueous solution and form cell outer membrane mimetic surfaces. Static contact angle, atomic force microscope (AFM) and X-ray photoelectron spectra (XPS) measurements confirm the successful fabrication of coatings on polydopamine (PDA) precoated surfaces. Real-time interaction results between proteins/bacteria and the coatings measured by surface plasmon resonance (SPR) technique suggest excellent anti-protein adsorption and short-term anti-bacteria adhesion performance. The long-term bacteria adhesion, platelet and L929 cell attachment results strongly support the SPR conclusions. Furthermore, the cell membrane mimetic and mussel adhesive protein mimetic PEG-2c-23PC shows hardly any toxicity to L929 fibroblasts, and the coating surface demonstrates the best anti-biofouling performance. This PDA-assisted immobilization of PC and/or catechol modified multi-arm PEGs provides a convenient and universal way to produce a biocompatible and fouling-resistant surface with tailor-made functions, which hopefully can be expanded to a wider range of applications based on both structure and surface superiorities.

17.
J Mater Chem B ; 3(20): 4181-4190, 2015 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-32262295

RESUMEN

Mussel inspired polydopamine (PDA) coating has been proven to be a simple and effective method for surface modification of biomaterials. However, the adhesive functional groups remaining on the surface of PDA coating may promote the attachment of nonspecific proteins and microorganisms and hinder anti-biofouling performance. In this study, the PDA coating formation process is monitored in real-time by a sensitive surface plasmon resonance (SPR) technique at different pH values, initial dopamine concentrations and deposition times. The coating morphology is observed by atomic force microscopy (AFM). Nonspecific protein adsorption, platelet and fibroblast cell adhesion, as well as bacteria attachment on the PDA coatings of different thicknesses are measured to evaluate their anti-biofouling performance. Thickness-dependent biofouling of the PDA coatings is demonstrated by the accumulation of adhesive functional groups within the PDA matrix. In order to reduce the biofouling, we treat the PDA coating by FeCl3 coordination, NaIO4 oxidation, heating in air and grafting with a phosphorylcholine copolymer bearing active ester groups. The modified surfaces are characterized by X-ray photoelectron spectroscopy (XPS) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy measurements. Interestingly, all the treatments help to resist protein adsorption significantly. More excitingly, the simple grafting strategy with a phosphorylcholine copolymer can resist more than 99% of platelet, fibroblast, and bacteria cell attachment, 98% of bovine serum albumin and 95% of bovine plasma fibrinogen adsorption on the PDA coating. These results may find applications in the vast area of surface antifouling, especially for most biomedical devices.

18.
Ecotoxicol Environ Saf ; 111: 256-62, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25450942

RESUMEN

Medicinal insects have been widely used to cure human diseases for ages. Nevertheless, knowledge about the toxic chemicals accumulated in medicinal insects and their effects on human health was insufficient. In the present study, sixteen priority polycyclic aromatic hydrocarbons (PAHs) and nine halogenated PAHs (HPAHs) were determined in farmed medicinal cockroaches to address this issue. Total concentrations of PAHs in young nymphs, old nymphs, and adults ranged from 162 to 1025, 252 to 967, and 267 to 1168 ng/g, respectively. Levels of the sum of HPAHs varied from 0.84 to 9.17, 1.86 to 5.21, and 1.01 to 8.60 ng/g for young nymphs, old nymphs, and adults, respectively. The daily intake and excess cancer risk of PAHs and HPAHs were calculated for people who take cockroach-related drugs. Our results indicated that females and children have slightly higher exposure levels from the perspectives of gender and age, respectively. The estimated excess cancer risk of PAHs and HPAHs were both lower than the priority risk level (10(-4)), indicating a low potential carcinogenic risk with the medicinal cockroach consumption.


Asunto(s)
Cucarachas/química , Exposición a Riesgos Ambientales/análisis , Hidrocarburos Halogenados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Adulto , Animales , Niño , Femenino , Humanos , Masculino , Ninfa/química , Adulto Joven
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(1): 151-6, 2014 Jan.
Artículo en Chino | MEDLINE | ID: mdl-24783551

RESUMEN

The present paper,on the basis of analyzing the terrain scattering characteristics, proposed a novel supervised classification method combined with complex Wishart classifier ideology. This method used coherent matrix which almost contains all the polarization information to make subsequent adjustments for the supervised classification result to achieve higher accuracy division categories. For the first beginning, supervised classification was carried out on the Cloude & Pottier polarimetric characteristics combination to get the initial classification result. Then, in order to achieve the purpose to correct the mistakes resulting from just using the spatial distribution of feature vectors in supervised classification, we did some analysis as follow. The accuracy analysis of the classification results and the analysis of study area feature scattering similarity play an important role in our study to help us make the determination that the pixels need to be adjusted. Furthermore, taking the mean value of each category coherence matrix as the initial cluster centers of subsequent iterations, and using Kernel Fuzzy C-Means algorithm to adjust the fixed pixel set categories by subsequent category iterative correction, the fine and high-accuracy classification results were obtained, combined with complex Wishart distribution of coherence matrix. The domestic X-band full polarization SAR data of Lingshui area in Hainan province was applied in this classification experiment. The experiment results demonstrate that the proposed method can obtain a favorable classification accuracy polarization SAR image classification results, and better meet the scattering characteristics of the surface objects compared to the original method.

20.
J Biomed Mater Res A ; 102(9): 2972-81, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24115737

RESUMEN

Control over cell-material surface interactions is the key to many new and improved biomedical devices. In this study, we present a simple yet effective surface modification method that allows for the surface reconstruction and formation of cell outer membrane mimetic structure on coatings that have significantly increased hemocompatibility. To achieve this, a phosphorylcholine end-capped poly(butylene succinate) (PBS-PC) was synthesized and dip-coated on coverslips. The surface structure of the amphiphilic PBS-PC film was reconstructed by heating in a vacuum oven to obtain the less hydrophilic surface and by immersing in hot water to obtain the more hydrophilic surface. Significant changes in the surface element concentration were observed by X-ray photoelectron spectroscopy analysis and changes in surface wettability were measured by sensitive dynamic contact angle technique. Scanning electron microscope images showed different morphologies of the reconstructed surfaces. Interestingly, the reconstruction between the less hydrophilic and more hydrophilic surfaces is reversible. More importantly, both the reconstructed surfaces are stable in room condition for more than 6 months, and both the surfaces show significant improvement in hemocompatibility as revealed by protein adsorption and platelet adhesion measurements. This reversible surface reconstruction strategy and the interesting results may be significant for fabricating stable and hemocompatible surfaces on differently shaped biomedical devices.


Asunto(s)
Butileno Glicoles/química , Materiales Biocompatibles Revestidos/química , Fosforilcolina/química , Polímeros/química , Plaquetas/citología , Butileno Glicoles/metabolismo , Materiales Biocompatibles Revestidos/metabolismo , Humanos , Ensayo de Materiales , Fosforilcolina/metabolismo , Espectroscopía de Fotoelectrones , Adhesividad Plaquetaria , Polímeros/metabolismo , Propiedades de Superficie
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