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1.
J Cell Physiol ; 234(7): 10771-10781, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30480804

RESUMEN

The purpose of this study was to develop a novel approach to treat bone osteosarcoma using a multipurpose scaffold aiming for local drug delivery. The slowly releasing microspheres was designed to deliver the chemotherapy drug adriamycin (ADM) and a decellularized (D) periosteum scaffold (which is known to be able to promote bone regeneration) was used to carry these microspheres. D-periosteum was obtained by physical and chemical decellularization. Histological results showed that the cellular components were effectively removed. The D-periosteum showed an excellent cytocompatibility and the ability to promote adhesion and growth of fibroblasts. Two kinds of slowly releasing microspheres, adriamycin gelatin microspheres (ADM-GMS) and adriamycin poly (dl-lactide-co-glycolide) gelatin microspheres (ADM-PLGA-GMS), were prepared and anchored to D-periosteum, resulting in two types of drug-releasing regenerative scaffolds. The effectiveness of these two scaffolds in killing human osteosarcoma cells was tested by evaluating cell viability overtime of the cancer cells cultured with the scaffolds. In summary, a gelatin/decellularized periosteum-based biologic scaffold material was designed aiming for local delivery of chemotherapy drugs for osteosarcoma, with the results showing ability of the scaffolds in sustaining release of the cancer drug and in suppressing growth of the cancer cells in vitro.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Neoplasias Óseas/tratamiento farmacológico , Doxorrubicina/administración & dosificación , Portadores de Fármacos , Gelatina/química , Osteosarcoma/tratamiento farmacológico , Periostio/citología , Andamios del Tejido , Animales , Antibióticos Antineoplásicos/efectos adversos , Neoplasias Óseas/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Preparaciones de Acción Retardada , Doxorrubicina/química , Humanos , Masculino , Microesferas , Osteosarcoma/patología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Ratas Sprague-Dawley , Factores de Tiempo
2.
Molecules ; 23(12)2018 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-30513654

RESUMEN

Recently, composite materials with nonlinear dielectric or resistive properties performed well in electric field homogenization and space charge suppression in a high voltage transmission and distribution system. For the purpose of obtaining insulation materials with desirable dielectric and electrical resistance properties, we investigated several fillers with nonlinear electrical properties doped in silicon rubber composites, and their dependency on the temperature and field. The samples of silicone rubber composites with different components were prepared using barium strontium titanate (BST) and zinc oxide (ZnO) as the filler, and high temperature vulcanized silicone rubber (SiR) as the matrix. The investigations revealed that the BST-doped samples showed different dielectric properties compared to ZnO-doped composites, with an increase in the electric field, which was nonlinear. The resistivity of both doped samples was similar. Results demonstrated that it was possible to achieve higher values of permittivity, and lower values of tanδ and resistivity, with respect to unfilled silicone rubber composites over a wide electrical field and temperature range. Discussion of the results attributes these important functional behaviours to the spontaneous polarization of nonlinear nanoparticles and the interaction between the SiR chains and the nonlinear nanoparticles at the interfacial area.


Asunto(s)
Electricidad , Nanopartículas/química , Dinámicas no Lineales , Óxidos/química , Elastómeros de Silicona/química , Estroncio/química , Titanio/química , Óxido de Zinc/química , Simulación por Computador , Conductividad Eléctrica , Nanopartículas/ultraestructura , Difracción de Rayos X
3.
J Craniofac Surg ; 27(3): e228-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27159868

RESUMEN

The straight midline lower lip-splitting incision has traditionally been performed with different types of deep intraoral malignancies for obtaining wide surgical access, and it can also be extended to the submandibular region or the neck to concurrently perform a neck dissection. But meanwhile, it is associated with unfavorable aesthetic and functional complications such as conspicuous facial scar, lip vermilion notching, stenosis of the labial sulcus, decreased lip sensation and movement, and oral incontinence. We designed a more favorable lower-lip incision, namely, para-lower lip incision, using the exposure and en blot resection of deep intraoral tumors. Compared with the traditional incision line, our designed line is shorter, and 20 outpatients (primary tumor site including buccal mucosa, tongue, mandibular gingiva, maxillary sinus, palate, and mouth floor) follow-ups indicated the postoperative scar is inconspicuous, no lip contour deformity and dysfunction or complications of facial paralysis such as distortion of commissure happened. This article reports one case of our patients who underwent para-lower-lip incision approach for the removal of squamous cell carcinoma (T3N2M0) in the left plate and the results of the patient were favorable.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Labio/cirugía , Neoplasias Maxilares/cirugía , Colgajos Quirúrgicos , Neoplasias de la Lengua/cirugía , Carcinoma de Células Escamosas/diagnóstico , Femenino , Humanos , Labio/patología , Neoplasias Maxilares/diagnóstico , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias de la Lengua/diagnóstico
4.
J Environ Sci (China) ; 42: 227-235, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27090715

RESUMEN

The colloidal properties of biogenic elemental sulfur (S(0)) cause solid-liquid separation problems, such as poor settling and membrane fouling. In this study, the separation of S(0) from bulk liquids was performed using flocculation. Polyaluminum chloride (PAC), polyacrylamide (PAM) and microbial flocculant (MBF) were compared to investigate their abilities to flocculate S(0) produced during the treatment of sulfate-containing wastewater. A novel approach with response surface methodology (RSM) was employed to evaluate the effects and interactions of flocculant dose, pH and stirring intensity, on the treatment efficiency in terms of the S(0) flocculation and the supernatant turbidity removal. The dose optimization results indicated that the S(0) flocculation efficiency decreased in the following order PAC>MBF>PAM. Optimum S(0) flocculation conditions were observed at pH4.73, a stirring speed of 129 r/min and a flocculant dose of 2.42 mg PAC/mgS. During optimum flocculation conditions, the S(0) flocculation rate reached 97.53%. Confirmation experiments demonstrated that employing PAC for S(0) flocculation is feasible and RSM is an efficient approach for optimizing the process of S(0) flocculation. The results provide basic parameters and conditions for recovering sulfur during the treatment of sulfate-laden wastewaters.


Asunto(s)
Azufre/análisis , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Resinas Acrílicas/química , Hidróxido de Aluminio/química , Floculación , Residuos Industriales , Azufre/química , Contaminantes Químicos del Agua/química
5.
Anal Chem ; 87(20): 10535-41, 2015 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-26393404

RESUMEN

Intracellular temperature has a fundamental effect on cellular events. Herein, a novel fluorescent polymer ratiometric nanothermometer has been developed based on transferrin protein-stabilized gold nanoclusters as the targeting and fluorescent ratiometric unit and the thermosensitve polymer as the temperature sensing unit. The resultant nanothermometer could feature a high and spontaneous uptake into the HeLa cells and the ratiometric temperature sensing over the physiological temperature range. Moreover, the precise temperature sensing for intracellular heat generation in HeLa cells following calcium ions stress has been achieved. This practical intracellular thermometry could eliminate the interference of the intracellular surrounding environment in cancer cells without a microinjection procedure, which is user-friendly. The prepared new nanothermometer can provide tools for unveiling the intrinsic relationship between the intracellular temperature and ion channel function.


Asunto(s)
Fenómenos Fisiológicos Celulares , Polímeros/química , Temperatura , Termómetros , Supervivencia Celular , Fluorescencia , Células HeLa , Humanos , Polímeros/síntesis química , Espectrometría de Fluorescencia , Termogénesis
6.
Anal Chem ; 87(9): 4765-71, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25822074

RESUMEN

Recently, semiconducting polymer dots (Pdots) have become a novel type of ultrabright fluorescent probes which hold great promise in biological imaging and analytical detection. Here we developed a visual sensor based on Pdots for Pb(2+) detection. We first embedded near-infrared (NIR) dyes into the matrix of poly[(9,9-dioctylfluorene)-co-2,1,3-benzothiadiazole-co-4,7-di(thiophen-2-yl)-2,1,3-benzothiadiazole] (PFBT-DBT) polymer and then capped the Pdots with polydiacetylenes (PDAs), in which parts of the PDAs were prefunctionalized with 15-crown-5 moieties to form Pdots. The high selectivity of these Pdots for lead ions is attributed to the formation of 2:1 15-crown-5-Pb(2+)-carboxylate sandwich complex on the Pdot surface. After Pb(2+) chelation, the conjugation system of the PDA was perturbed and strained, causing a chromatic change of the PDA from blue to red. At the same time, the encapsulated NIR dyes were liable to leach out that resulted in an emission variation of the Pdots. Accordingly, lead ions can be recognized by either color change or emission variation of the Pdots. We also loaded these nanoprobes into live HeLa cells through endocytosis, and then monitored changes in Pb(2+) levels within cells, demonstrating their utility for use in cellular and bioimaging applications. In addition, we fabricated easy-to-prepare test strips impregnated with Pdot-poly(vinyl alcohol) films to identify Pb(2+) in real samples, which proved their applicability for in situ on-site detection. Our results suggest that this Pdot-based visual sensor shows promising potential for advanced environmental and biological applications.


Asunto(s)
Colorimetría , Colorantes Fluorescentes/análisis , Plomo/análisis , Polímeros/química , Semiconductores , Supervivencia Celular , Colorantes Fluorescentes/química , Células HeLa , Humanos , Iones/análisis , Estructura Molecular , Espectrometría de Fluorescencia
7.
J Oral Maxillofac Surg ; 73(4): 675.e1-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25795579

RESUMEN

PURPOSE: Some believe that the recurrence of sublingual ranula results from incomplete removal of the sublingual gland (SLG), but recurrence remains in some patients who undergo repeated excision of the remnant SLG, and the final solution to the recurrence is to remove the ipsilateral submandibular gland (SMG). In the authors' experience, preoperative aspirate from a sublingual ranula was a thick mucus-like fluid resembling egg white, whereas that from recurrent cyst after removal of the SLG was thin serous fluid. Based on the difference of the aspirated fluids, the authors speculated that the recurrent cystic mass might not be a ranula, but rather iatrogenic saliva leakage from the SMG through the previous surgically damaged excretory duct of the SLG (Bartholin duct) that opens into the SMG duct (Wharton duct). MATERIALS AND METHODS: A gross anatomic study was performed of the ductal system of the SLG and the anatomic communication between the Bartholin duct and Wharton duct. RESULTS: Four anatomic SLG duct variants were found. 1) The SLG has 1 Bartholin duct that seems to fuse with the Wharton duct but does not join the Wharton duct, running parallel to the Wharton duct and opening at its own orifice adjacent to and a short distance from the orifice of the Wharton duct (35.8%). 2) The SLG has 1 Bartholin duct that empties into the middle section of the Wharton duct (32.1%). 3) The SLG has 2 Bartholin ducts, one of which joins the Wharton duct and the other opens at its own orifice near that of the Wharton duct on the floor of the mouth (7.1%). 4) The SLG has many fine ducts (Rivinus ducts) that open at the floor of the mouth with no relation to the Wharton duct (25.0%). Of the 4 anatomic SLG duct variations, types 2 and 3 form immediate anatomic communication between the Bartholin duct and Wharton duct (39.2%). CONCLUSIONS: Several conclusions can be made from the present anatomic findings. 1) A certain proportion of Bartholin ducts open into the Wharton duct, and "recurrent ranula" after removal of the SLG can result from iatrogenic saliva leakage from the SMG through the surgically severed Bartholin duct if the aspirated fluid from the "recurrent cyst" is a thin seriflux. 2) The Bartholin duct emptying into the Wharton duct should be ligated during removal of the SLG to prevent local saliva accumulation from the SMG or even caudal "recurrence" as plunging ranula. 3) The surgical incision for SLG removal should be sutured loosely so that the surgically severed Bartholin duct with communication to the Wharton duct can reopen at the floor of mouth as an outlet for possible saliva leakage from the SMG and saliva accumulation can be avoided.


Asunto(s)
Ránula/etiología , Saliva/metabolismo , Conductos Salivales/patología , Enfermedades de las Glándulas Salivales/etiología , Glándula Sublingual/patología , Glándula Submandibular/patología , Adenocarcinoma/cirugía , Variación Anatómica , Carcinoma de Células Escamosas/cirugía , Humanos , Suelo de la Boca/cirugía , Neoplasias de la Boca/cirugía , Estudios Prospectivos , Recurrencia , Conductos Salivales/anomalías , Neoplasias de la Glándula Sublingual/cirugía
8.
Anal Chem ; 86(10): 4831-9, 2014 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-24749695

RESUMEN

Semiconducting polymer dots (P-dots) recently have emerged as a new type of ultrabright fluorescent probe with promising applications in biological imaging and detection. With the increasing desire for near-infrared (NIR) fluorescing probes for in vivo biological measurements, the currently available NIR-emitting P-dots are very limited and the leaching of the encapsulated dyes/polymers has usually been a concern. To address this challenge, we first embedded the NIR dyes into the matrix of poly[(9,9-dioctylfluorene)-co-2,1,3-benzothiadiazole-co-4,7-di(thiophen-2-yl)-2,1,3-benzothiadiazole] (PF-BT-DBT) polymer and then enclosed the doped P-dots with polydiacetylenes (PDAs) to avoid potential leakage of the entrapped NIR dyes from the P-dot matrix. These PDA-enclosed NIR-emitting P-dots not only emitted much stronger NIR fluorescence than conventional organic molecules but also exhibited enhanced photostability over CdTe quantum dots, free NIR dyes, and gold nanoclusters. We next conjugated biomolecules onto the surface of the resulting P-dots and demonstrated their capability for specific cellular labeling without any noticeable nonspecific binding. To employ this new class of material as a facile sensing platform, an easy-to-prepare test paper, obtained by soaking the paper into the PDA-enclosed NIR-emitting P-dot solution, was used to sense external stimuli such as ions, temperature, or pH, depending on the surface functionalization of PDAs. We believe these PDA-coated NIR-fluorescing P-dots will be very useful in a variety of bioimaging and analytical applications.


Asunto(s)
Técnicas Biosensibles , Colorantes Fluorescentes/química , Poliinos/química , Espectroscopía Infrarroja Corta/métodos , Fluorescencia , Células HeLa , Humanos , Polímeros/química , Semiconductores
9.
J Org Chem ; 78(7): 3235-42, 2013 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-23437889

RESUMEN

Complexation between a triptycene-derived macrotricyclic polyether containing two dibenzo-[30]-crown-10 cavities and different functionalized paraquat derivatives, diquat, and a 2,7-diazapyrenium salt in both solution and solid state was investigated in detail. It was found that depending on the guests with different terminal functional groups and structures, the macrotricyclic polyether could form 1:1 or 1:2 complexes with the guests in different complexation modes in solution and also in the solid state. Especially, the conformation of the macrotricyclic polyether was efficiently adjusted by the encapsulated guests, which was to some extent similar to substrate-induced fit of enzymes. Moreover, the binding and releasing of the guests in the complexes could be controlled by potassium ions.


Asunto(s)
Antracenos/química , Diquat/química , Éteres/química , Paraquat/química , Fenantrolinas/química , Polímeros/química , Compuestos Macrocíclicos/química , Modelos Moleculares , Conformación Molecular , Sales (Química)/química
10.
Bioresour Technol ; 344(Pt B): 126261, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34728353

RESUMEN

Lignocellulose has been considered a potential feedstock for biohydrogen production. Recently, a novel closed-loop concept of biochar approach was developed for enhanced lignocellulosic biohydrogen production. This study therefore targets to analyze the environmental impacts of the three existing lignocellulosic biohydrogen production processes, and evaluate the environmental performance of applying biochar in each process at this early stage of technological development. The results suggest that biochar dosing shows better environmental performance for all impact categories, especially in the consolidate bioprocessing case. Electricity consumption was found to be the dominant cause of environmental impact over the life cycle, while by-products generation was also found to have an effect on the life-cycle impacts. Future research focuses on the biohydrogen production scale, the electricity generation scheme transition towards renewable and cleaner energetic systems, and recovery the by-products to the maximum extent, that will make lignocellulosic biohydrogen production more environmentally sustainable.


Asunto(s)
Hidrógeno , Estadios del Ciclo de Vida , Animales , Carbón Orgánico , Fermentación , Lignina
11.
Bioresour Technol ; 343: 126123, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34653621

RESUMEN

As a clean and renewable energy, bioenergy is one of the most promising alternatives to fossil fuels. Lignocellulose possesses great potential for bioenergy production, but the recalcitrant and heterogeneous structure limits its application. Pretreatment technology offers an effective solution to fractionate the main components of the lignocellulose and uncover the available cellulose. The obtained feedstock can be applied to bioconversion into energy, e.g., bioethanol, biogas, biohydrogen, etc. Here, the current state of lignocellulose pretreatment technologies was comprehensively reviewed, the advances in bioenergy production from pretreated lignocellulose was described, with particular attention to key challenges involved. Several new strategies for overcoming pretreatment barriers to realize highly efficient lignocellulose bioconversion were highlighted. The insights given in this review will facilitate further development on lignocellulosic bioenergy production, towards addressing the global energy crisis and climate change related to the use of fossil fuels.


Asunto(s)
Biocombustibles , Lignina , Biomasa , Celulosa
12.
Chem Asian J ; 17(21): e202200621, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-35945646

RESUMEN

Thermogels, a class of hydrogels which show spontaneous sol-gel phase transition when warmed, are an important class of soft biomaterials. To date, however, most amphiphilic polymers that are able to form thermogels in aqueous solution are uncharged, and the influence of ionisable groups on thermogelation are largely unknown. Herein, we report the first example of a polyanionic amphiphilic multi-block copolymer, containing multiple pendant carboxylate groups, that can form transparent thermogels spontaneously when warmed up to physiological temperature. We demonstrate that introducing negative charges onto thermogelling polymers could significantly alter the properties of the micelles and thermogels formed. Furthermore, the polymer's polyanionic character provides new options for modulating the gel rheological properties, such as stiffness and gelation temperatures, through electrostatic interactions with different cations. We also demonstrated that the polyanionic thermogel allowed slower sustained release of a cationic model drug compound compared to an anionic one over 2 weeks. The findings from our study demonstrate exciting new possibilities for advanced biomedical applications using charged polyelectrolyte thermogel materials.


Asunto(s)
Hidrogeles , Tartratos , Temperatura , Polielectrolitos , Polímeros
13.
Biomaterials ; 280: 121262, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34810039

RESUMEN

Vitreous endotamponades play essential roles in facilitating retina recovery following vitreoretinal surgery, yet existing clinically standards are suboptimal as they can cause elevated intra-ocular pressure, temporary loss of vision, and cataracts while also requiring prolonged face-down positioning and removal surgery. These drawbacks have spurred the development of next-generation vitreous endotamponades, of which supramolecular hydrogels capable of in-situ gelation have emerged as top contenders. Herein, we demonstrate thermogels formed from hyper-branched amphiphilic copolymers as effective transparent and biodegradable vitreous endotamponades for the first time. These hyper-branched copolymers are synthesised via polyaddition of polyethylene glycol, polypropylene glycol, poly(ε-caprolactone)-diol, and glycerol (branch inducing moiety) with hexamethylene diisocyanate. The hyper-branched thermogels are injected as sols and undergo spontaneous gelation when warmed to physiological temperatures in rabbit eyes. We found that polymers with an optimal degree of hyper-branching showed excellent biocompatibility and was able to maintain retinal function with minimal atrophy and inflammation, even at absolute molecular weights high enough to cause undesirable in-vivo effects for their linear counterparts. The hyper-branched thermogel is cleared naturally from the vitreous through surface hydrogel erosion and negates surgical removal. Our findings expand the scope of polymer architectures suitable for in-vivo intraocular therapeutic applications beyond linear constructs.


Asunto(s)
Endotaponamiento , Cuerpo Vítreo , Animales , Hidrogeles , Peso Molecular , Poliésteres , Polietilenglicoles , Conejos , Cuerpo Vítreo/cirugía
14.
Artículo en Inglés | MEDLINE | ID: mdl-34484408

RESUMEN

BACKGROUND: The most widely used frailty phenotype and frailty indexes are either time-consuming or complicated, thus restricting their generalization in clinical practice; and therefore, an easier and faster screening tool is needed to be developed. OBJECTIVE: To select sensitive symptoms in traditional Chinese medicine (TCM) and study whether they can improve the risk prediction of frailty. METHODS: This is a cross-sectional study enrolling 2249 Chinese elderly community dwellers. Data were collected via face-to-face inquiries, anthropometric measurements, laboratory tests, and community health files. Frailty was the main outcome measure, and it was evaluated by Fried's frailty phenotype (FP). The ordinal logistic regression model was used to identify the factors associated with frailty. The risk assessment plot was used to compare the discriminative ability for frailty among models with and without TCM symptoms. RESULTS: The identified sensitive influential factors for frailty included age, education level, dietary habits, chronic obstructive pulmonary disease, diabetes, cerebral infarction, osteoporosis, cold limbs, lethargy and laziness in speaking and moving, weakness of lower limbs, slow movement, dry mouth and throat, and glazed expression. The risk prediction for "frailty cumulative components ≥1" was not significantly increased, while for "frailty cumulative components ≥2", a new model developed with the above selected TCM symptoms had a higher AUC than the baseline model without it (0.79 VS 0.81, P=0.002). And the NRI and IDI for the new model were 41.4% (P=0.016) and 0.024% (P=0.041), respectively. CONCLUSION: This research might provide an easier and faster way for early identification and risk prediction of frailty in elderly community dwellers.

15.
Environ Pollut ; 274: 116524, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33548667

RESUMEN

Increasing attention has been brought to microplastics pollution recently, while emerging evidences indicate that nano-plastics degraded from microplastics are more of research significance owing to stronger toxicity. However, there is little study focused on the prevention of nano-plastics induced toxicity until now. Canidin-3-glucoside (C3G), a natural anthocyanin proved to possess multiple functions like antioxidant and intestinal tissue protection. Thus, we proposed whether C3G could act as a molecular weapon against nano-plastics induced toxicity. In Caco2 cell and Caenorhabditis elegans (C. elegans) models, we found that polystyrene (PS) nano-plastics exposure resulted in physiological toxicity and oxidative damage, which could be restored by C3G. More significantly in Caco2 cells, we observed that autophagy was activated via Sirt1-Foxo1 signaling pathway to attenuate PS induced toxicity after C3G intervention and further verified by adding autophagy inhibitor 3-Methyladenine (3-MA). Meanwhile, PS co-localization with lysosomes was observed, indicating the encapsulation and degradation of PS. In C. elegans, by detecting LGG-1/LC3 expression in GFP-targeted LGG-1 report gene (LGG-1:GFP) labeled transgenic DA2123 strain, the co-localization of LGG-1:GFP with PS was found as well, means that autophagy is involved in C3G's beneficial effects. Furthermore, we were surprised to find that C3G could promote the discharge of PS from N2 nematodes, which reduces PS toxicity more directly.


Asunto(s)
Caenorhabditis elegans , Plásticos , Animales , Autofagia , Células CACO-2 , Glucósidos/toxicidad , Humanos , Microplásticos
16.
ACS Appl Bio Mater ; 3(9): 6131-6144, 2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-35021746

RESUMEN

This paper is a continued study on laser cleaning removal of marine microbiofouling from Al alloy surfaces. According to our previous study, it is noted that the antifouling functions of the generated laser-cleaned metallic surfaces must be highlighted. In this work, the inhibition effectiveness of the laser-cleaned Al alloy surfaces was evaluated using a type of vital marine microorganism, sulfate-reducing bacteria (SRB) Desulfovibrio desulfuricans subsp. desulfuricans, in a dynamic bacterial solution. Before the immersion tests, the laser-cleaned surfaces with nanostructures were chemically processed into superhydrophilic, superhydrophobic, and ultraslippery surfaces. SRB attachment behaviors as well as inhibition mechanisms of the three surfaces to the SRB settlement were characterized and revealed. The SRB adhering to the above surfaces presented three different morphologies, i.e., broken, dented, and plump cells. Superhydrophilic surfaces unexpectedly showed a not inferior antibacterial ability. A piercing effect of the nanostructures caused nontoxic mechanical damage to the cell membranes. The antiadhesion property of superhydrophobic solid-air hybrid surfaces was unreliable due to the loss of air bubbles. The morphology of the last surviving SRB cells left on the ultraslippery surfaces was basically plump. The stable repellent function of the surfaces was responsible for the vigorous prevention of the adhesion of the SRB. The research results offer an insight into the antibacterial/antiadhesion properties of the laser-cleaned surfaces and a practical value for the periodic service of marine high-end equipment.

17.
Nat Commun ; 11(1): 2240, 2020 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-32382025

RESUMEN

Rare occurrences of dinosaurian embryos are punctuated by even rarer preservation of their development. Here we report on dental development in multiple embryos of the Early Jurassic Lufengosaurus from China, and compare these to patterns in a hatchling and adults. Histology and CT data show that dental formation and development occurred early in ontogeny, with several cycles of tooth development without root resorption occurring within a common crypt prior to hatching. This differs from the condition in hatchling and adult teeth of Lufengosaurus, and is reminiscent of the complex dentitions of some adult sauropods, suggesting that their derived dental systems likely evolved through paedomorphosis. Ontogenetic changes in successive generations of embryonic teeth of Lufengosaurus suggest that the pencil-like teeth in many sauropods also evolved via paedomorphosis, providing a mechanism for the convergent evolution of small, structurally simple teeth in giant diplodocoids and titanosaurids. Therefore, such developmental perturbations, more commonly associated with small vertebrates, were likely also essential events in sauropod evolution.


Asunto(s)
Dentición , Dinosaurios , Fósiles , Animales , Evolución Biológica , Filogenia
18.
J Mater Chem B ; 8(1): 65-77, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31768514

RESUMEN

Gold nanostars (AuNSs), with unique physicochemical properties, are thought to be a promising agent for photothermal therapy (PTT). In this study, we prepared PEGylated gold nanostars (pAuNSs) using the HEPES-reduction method. The high photothermal conversion efficiency (∼80%) and photothermal stability of pAuNSs were demonstrated in vitro and in vivo. 111In-DTPA-pAuNSs were prepared as a radioactive surrogate for the biodistribution studies of pAuNSs. In both microSPECT/CT images and the biodistribution study, the tumor-to-muscle (T/M) ratio reached a maximum at 24 h post intravenous injection of 111In-DTPA-pAuNSs. The high linear correlation between the 111In radioactivity and the gold content in the tumors (R2 0.86-0.99) indicated that 111In-DTPA-pAuNSs were appropriate for noninvasively tracking pAuNSs in vivo after systemic administration. Histological examination after silver enhancement staining clearly illustrated that the accumulated pAuNSs in the tumors were mainly located on the luminal surface of vessels. The mice bearing a SKOV-3 xenograft exhibited remarkable therapeutic efficacy with negligible organ damage after receiving pAuNS-mediated photothermal therapy. Our findings suggested that pAuNSs, together with their radioactive surrogate 111In-DTPA-pAuNSs, are promising for applications in image-guided photothermal therapy.


Asunto(s)
Oro/farmacocinética , Nanopartículas del Metal/uso terapéutico , Neoplasias/terapia , Fototerapia/métodos , Polietilenglicoles/farmacocinética , Nanomedicina Teranóstica/métodos , Animales , Línea Celular Tumoral , Femenino , Oro/uso terapéutico , Humanos , Ratones , Ratones Endogámicos BALB C
19.
Shanghai Kou Qiang Yi Xue ; 28(2): 201-203, 2019.
Artículo en Zh | MEDLINE | ID: mdl-31384910

RESUMEN

PURPOSE: To explore a safe, effective and functional surgical treatment for children of Pierre Robin sequence (PRS) with cleft palate. METHODS: Twelve children of PRS with cleft palate underwent mandibular distraction osteogenesis before cleft palate surgery in order to correct severe hypoxia. A modified palatoplasty was then performed, the palatal flaps on both sides were not elevated in the anterior portions to prevent soft palate backward moving, and the levator veli palatini was repositioned simultaneously. RESULTS: All children achieved velopharyngeal closure without dyspnea after follow-up of 10-12 months. CONCLUSIONS: Measures should be taken to avoid backward movement of the soft palate, which may result in dyspnea of children with PRS in palatoplasty.


Asunto(s)
Fisura del Paladar , Osteogénesis por Distracción , Síndrome de Pierre Robin , Niño , Fisura del Paladar/cirugía , Humanos , Osteogénesis por Distracción/métodos , Paladar Blando , Síndrome de Pierre Robin/cirugía , Colgajos Quirúrgicos
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