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1.
Braz Oral Res ; 33: e086, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31483052

RESUMO

Treatment of patients with bisphosphonate usage is a significant concern for oral surgeons because it interferes with jaw bone turnover and regeneration. In case of adverse effects manifesting related to bisphosphonate use, oral surgeons are usually treating and keep the patient's symptoms under control. In this study, we aimed to investigate a new treatment protocol for medication-related osteonecrosis of the jaw (MRONJ). This treatment protocol consisted of administering human parathyroid hormone (hPTH) loaded chitosan microspheres which were prepared by ionotropic gelation method or/and the prepared microspheres were suspended in a poloxamer gel. After in-vitro optimization studies, the efficacy of the chosen formulations was evaluated in-vivo studies. Zoledronic acid was administered daily to forty-eight adult female Sprague-Dawley rats, divided into four experimental groups, at a daily concentration of 0.11 mg/kg over three weeks to induce the MRONJ model. At the end of this period, maxillary left molar teeth were extracted. In the first group, the subjects received no treatment. In the negative control group, poloxamer hydrogel containing empty microspheres were immediately applied to the soft tissues surrounding the extraction socket. The treatment group-1 was treated with local injections of poloxamer hydrogel containing hPTH. The treatment group-2 was treated with a single local injection of poloxamer hydrogel containing hPTH-loaded chitosan microspheres. Both treatment groups received a total of 7 µg of hPTH at the end of the treatment protocol. Our study demonstrates successful attenuation of MRONJ through a local drug delivery system combined with hPTH, as opposed to previously attempted treatment strategies.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Quitosana/farmacologia , Maxila/efeitos dos fármacos , Hormônio Paratireóideo/farmacologia , Animais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/tratamento farmacológico , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Quitosana/uso terapêutico , Preparações de Ação Retardada , Feminino , Humanos , Maxila/patologia , Microesferas , Modelos Animais , Hormônio Paratireóideo/uso terapêutico , Poloxâmero/administração & dosagem , Poloxâmero/química , Ratos Sprague-Dawley , Ácido Zoledrônico/efeitos adversos
3.
J Environ Manage ; 248: 109236, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31306926

RESUMO

Nano-layered double hydroxide (NLDH) decorated with Fe and Cu was applied as a novel heterogeneous catalyst for catalytic degradation of gentamicin by the electro-Fenton (EF) process. The EF process was equipped with graphite plate under aeration to electrochemically generate hydrogen peroxide in the solution. The characterization analyses confirmed the suitable structure of as-synthesized Cu-Fe-NLDH to be acted as catalyst for treating the target pollutant. The comparative study showed the highest removal efficiency of 91.3% when the Cu-Fe-NLDH-equipped EF process was applied in comparison with the Fenton (50%) and the electro-oxidation alone (25.6%). The acidic pHs favored the degradation of gentamicin. Increasing the current resulted in the enhanced degradation of gentamicin, while the excessive electrolyte concentration (0.1 mol/L) and catalyst dosage (1.5 g/L) led to the tangible drop in the reactor performance. At a specified reaction time, the injection of O3 gas enhanced the efficiency of the Cu-Fe-NLDH-equipped EF process. The presence of ethanol led to more suppressing effect than benzoquinone, indicating the dominant role of OH radical in the degradation of gentamicin compared with other free radical species such as O2- radical. Only 10% drop in the degradation efficiency of gentamicin was observed within 10 operational runs. The mineralization efficiency of about 77% was achieved after 300 min in terms of chemical oxygen demand (COD) removal. The intermediate byproducts generated during the destructive removal of gentamicin were also identified.


Assuntos
Gentamicinas , Poluentes Químicos da Água , Peróxido de Hidrogênio , Hidróxidos , Ferro , Microesferas , Oxirredução
4.
Food Chem ; 295: 259-266, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174757

RESUMO

New cauliflower-like phloroglucinol-glyoxylic acid resin microspheres (PGRMs) with controllable diameters and tuneable surface roughness were prepared using a one-step environmentally-friendly method without a catalyst. The PGRMs obtained exhibited a rough surface, narrow size distribution, and excellent adsorption capacity for polar compounds. The PGRMs were employed as an adsorbent for solid phase extraction (SPE) of kinetin (KT) and 6-benzyladenine (6-BA) in cucumbers and demonstrated better extraction recoveries and purification efficiency than phloroglucin-formaldehyde resin and common commercial adsorbents. Our PGRMs-SPE-HPLC method showed good linearity (r ≥ 0.9997) ranging from 0.04 to 4.00 µg/g for KT and 6-BA, and recoveries at three spiked concentration ranged from 77.8% to 104.4% with RSDs ≤ 6.8%. This PGRMs-SPE-HPLC method was applied successfully to determine of KT and 6-BA in cucumbers.


Assuntos
Compostos de Benzil/análise , Cucumis sativus/química , Cinetina/análise , Reguladores de Crescimento de Planta/análise , Purinas/análise , Extração em Fase Sólida/métodos , Adsorção , Compostos de Benzil/isolamento & purificação , Brassica/química , Cromatografia Líquida de Alta Pressão , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Glioxilatos/química , Cinetina/isolamento & purificação , Microesferas , Tamanho da Partícula , Floroglucinol/química , Reguladores de Crescimento de Planta/isolamento & purificação , Purinas/isolamento & purificação , Extração em Fase Sólida/instrumentação , Propriedades de Superfície
5.
Bioresour Technol ; 289: 121640, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31212176

RESUMO

Here we report a centrifugation-based fractionation methodology that was integrated with three types of organic solvents to fractionate industrial alkali lignin toward the fabrication of lignin microsphere. The Fourier-transform infrared spectroscopy (FT-IR) result showed that the chemical structure of lignin was not changed by solvent fractionation. Soluble lignin in each solvent had lower molecular weight, improved polydispersity index (PDI) and less impurities (S, N), while insoluble lignin had a high bio-char yield and can be utilized as potential carbon source for porous carbon nanosphere materials. In addition, well-shaped lignin microsphere with smooth or anisotropic surface can be prepared by selecting proper lignin fraction without any chemical modification. This work thus provides a new strategy for the derivation of lignin as raw materials for value-added products, which paved a new way to develop a green and sustainable bio-refining industry.


Assuntos
Álcalis , Lignina , Fracionamento Químico , Microesferas , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Photochem Photobiol Sci ; 18(8): 1933-1944, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31169269

RESUMO

Although natural exposure to ambient UV radiation in oligotrophic seawater at small depths can reach the levels responsible for cellular damage, the sea urchin Paracentrotus lividus is frequently in such sites, particularly on the southern Adriatic Sea shore. Spawning their eggs and spending their early life stage in rocky shores at depths of 0.5-2 m are the results of their successful adaptation strategies, although adults may dwell at greater depths. Surprisingly, there is a paucity of reports regarding the carotenoid content in sea urchin eggs. Beyond their important role in photoprotection against high UV exposure, cell division and early development, the content and distribution of carotenoids contribute to the successful survival of sea urchins and also determine the color of their gonads (roe), which is of commercial importance as a delicacy. Herein, for the first time, we have described the carotenoid content and distribution in intact, freshly released eggs of P. lividus species, non-destructively employing resonance Raman spectroscopy and imaging; near-infrared Raman spectroscopy revealed additional molecular carotenoid content. Echinenone and ß-carotene resonance Raman signals were the most intense, and they were identified as the principal carotenoids that are preferentially accumulated in eggs rather than in gonads. Raman imaging in confocal mode revealed the uniform distribution of the carotenoid signal over the whole eggs, while the distribution of proteins appeared spotted. Egg carotenoids generally maintained their identity after 2 months of dry storage, with slight signs of C[double bond, length as m-dash]C bond oxidation. The potential utilization of P. lividus sea urchin eggs as valuable microsphere packages of native carotenoids is discussed.


Assuntos
Carotenoides/análise , Ovos/análise , Microesferas , Ouriços-do-Mar/química , Ouriços-do-Mar/citologia , Animais , Análise Espectral Raman
7.
Int J Nanomedicine ; 14: 3471-3490, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190805

RESUMO

Background: Zinc-doped hydroxyapatite has been proposed as a graft biomaterial for bone regeneration. However, the effect of zinc on osteoconductivity is still controversial, since the release and resorption of calcium, phosphorus, and zinc in graft-implanted defects have rarely been studied. Methods: Microspheres containing alginate and either non-doped carbonated hydroxyapatite (cHA) or nanocrystalline 3.2 wt% zinc-doped cHA (Zn-cHA) were implanted in critical-sized calvarial defects in Wistar rats for 1, 3, and 6 months. Histological and histomorphometric analyses were performed to evaluate the volume density of newly formed bone, residual biomaterial, and connective tissue formation. Biomaterial degradation was characterized by transmission electron microscopy (TEM) and synchrotron radiation-based X-ray microfluorescence (SR-µXRF), which enabled the elemental mapping of calcium, phosphorus, and zinc on the microsphere-implanted defects at 6 months post-implantation. Results: The bone repair was limited to regions close to the preexistent bone, whereas connective tissue occupied the major part of the defect. Moreover, no significant difference in the amount of new bone formed was found between the two microsphere groups. TEM analysis revealed the degradation of the outer microsphere surface with detachment of the nanoparticle aggregates. According to SR-µXRF, both types of microspheres released high amounts of calcium, phosphorus, and zinc, distributed throughout the defective region. The cHA microsphere surface strongly adsorbed the zinc from organic constituents of the biological fluid, and phosphorus was resorbed more quickly than calcium. In the Zn-cHA group, zinc and calcium had similar release profiles, indicating a stoichiometric dissolution of these elements and non-preferential zinc resorption. Conclusions: The nanometric size of cHA and Zn-cHA was a decisive factor in accelerating the in vivo availability of calcium and zinc. The high calcium and zinc accumulation in the defect, which was not cleared by the biological medium, played a critical role in inhibiting osteoconduction and thus impairing bone repair.


Assuntos
Alginatos/química , Regeneração Óssea , Cálcio/metabolismo , Durapatita/química , Microesferas , Nanopartículas/química , Zinco/química , Zinco/metabolismo , Animais , Materiais Biocompatíveis/química , Disponibilidade Biológica , Regeneração Óssea/efeitos dos fármacos , Carbonatos/química , Morte Celular , Linhagem Celular , Sobrevivência Celular , Feminino , Camundongos , Nanopartículas/ultraestrutura , Ratos Wistar , Crânio/fisiologia , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
8.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(3): 477-486, 2019 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-31209419

RESUMO

OBJECTIVE: The current difficulties in the treatment of tumor include repeated administration and high recurrence rate after tumor resection. In order to reduce the number of doses, avoid side effects of chemotherapeutic drugs, suppress tumor growth and delay tumor recurrence after surgery, a temperature-sensitive in situ gel with paclitaxel microspheres (PTX/M gel) was prepared. PTX/M gel was administered by intratumoral injection once a month. METHODS: First of all, paclitaxel microspheres (PTX/M) were prepared by emulsion solvent evaporation method. A laser particle size distribution analyzer was used to investigate the size, distribution, specific surface area of microspheres. Paclitaxel content was determined by high performance liquid chromatography (HPLC). Then encapsulation efficiency of paclitaxel was calculated and in vitro release characteristics were studied. Secondly, PTX/M gel was prepared by cold dissolution method. The phase transition temperature, elastic modulus, dissolution curve, correlation between dissolution and release were measured. Finally, U87 MG and 4T1 subcutaneous tumor models were established respectively to study the efficacy of PTX/M gel in suppressing tumor growth and delaying tumor recurrence after surgery. RESULTS: The median diameter of the selected PTX/M was (32.24±1.09) µm, the specific surface area was (206.61±10.23) m2/kg, the encapsulation efficiency was 85.29%±1.34%, and the cumulative release percentage of paclitaxel from PTX/M was 33.56%±3.33% in one month. Phase transition temperature of PTX/M gel was 33 °C. The elastic modulus of PTX/M gel at 25 °C and 37 °C were 4.2×103 Pa and 18×103 Pa, respectively. The gel could stay in the body for up to 48 hours. It could be seen from the results of animal experiments that were compared with the saline group and the Taxol group, and the tumor-bearing mice of the PTX/M gel group had the slowest tumor growth (P<0.05). Similarly, in the tumor recurrence experiments, the mice of PTX/M gel group had the latest tumor recurrence after surgery. CONCLUSION: As a local sustained-release preparation, PTX/M gel can effectively suppress tumor growth and delay postoperative recurrence of tumors. It has potential advantages in tumor treatment.


Assuntos
Microesferas , Animais , Antineoplásicos Fitogênicos , Linhagem Celular Tumoral , Preparações de Ação Retardada , Camundongos , Paclitaxel
9.
Nuklearmedizin ; 58(3): 242-248, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31167272

RESUMO

AIM: To evaluate the feasibility of early metabolic response assessment with 18F-FDG PET/CT in patients with breast cancer liver metastases 4 weeks after radioembolization with Yttrium-90 labeled microspheres. METHODS: 25 patients (mean age 58y, range 40-74) with advanced stage liver metastases of breast cancer were treated with 1.9 ± 0.4 GBq of 90Y-microspheres in the salvage setting and underwent 18F-FDG PET/CT at baseline and 4 weeks post-radioembolization. 14 patients (56 %) had an excessive hepatic tumor burden (> 50 % of total liver volume), 21 patients (84 %) had extrahepatic disease. Liver lesions with the highest SUVmax were selected as target lesions and a cut-off was set at 50 % reduction to separate responders from non-responders. The predictive impact of metabolic response on overall survival (OS) was investigated along with other prognostic factors. RESULTS: The median OS in this highly advanced metastatic cohort was 7 months (95 % CI, 5-9). All patients had a reduction in SUVmax (mean ΔSUVmax: -49 ± 26 %) at 4 weeks post-treatment. Patients with > 50 % SUVmax reduction survived longer (median OS 13 mo, 95 % CI 8-18) than the remaining patients (median OS 4 mo, 95 % CI 2-6; p = 0.001). From all investigated baseline factors including age, performance status, and presence of extra-hepatic disease, only the hepatic tumor burden had a significant impact on OS (p = 0.02). CONCLUSIONS: This is the first preliminary evidence in breast cancer that early post-radioembolization molecular response assessment of treated liver metastases - as early as 4 weeks posttreatment - may predict survival. If confirmed by larger series, FDG PET/CT could be considered for early response-adapted treatment modifications.


Assuntos
Neoplasias da Mama/mortalidade , Fluordesoxiglucose F18/uso terapêutico , Neoplasias Hepáticas/mortalidade , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/uso terapêutico , Radioisótopos de Ítrio/uso terapêutico , Adulto , Idoso , Braquiterapia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Microesferas , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Radioisótopos de Ítrio/química
10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(2): 149-154, 2019 Apr 01.
Artigo em Chinês | MEDLINE | ID: mdl-31168980

RESUMO

OBJECTIVE: The purpose of this study is to investigate the effects of different drying methods on the physical properties and drug delivery of chitosan microspheres. METHODS: Three types of drying methods were utilized, including air drying and freeze drying after freezing at -20 ℃ (slow cooling) and at -80 ℃ (fast cooling). The physical properties of microspheres were characterized. Utilizing bovine serum albumin (BSA) as the model drug, the in-vitro release behaviors of drug-loaded beads were investigated. RESULTS: By comparing the physical properties of the different drying methods, the microspheres' diameters, porosities, and surface area were observed to increase successively from air drying and slow cooling to fast cooling, whereas the pore size and the swelling and degradation rates varied. The drug-loading experiments revealed that the loading capacity of air-dried microspheres was the lowest and the release rate was the slowest. Although the loading capacity of fast cooling microspheres was high, an obvious burst release was observed. The loading capacity of slow cooling microspheres was similar to that of the fast cooling microspheres and the loaded BSA can be released continuously. CONCLUSIONS: The results indicate that different drying methods can affect the physical properties of chitosan microspheres, which further influence drug loading and release.


Assuntos
Quitosana , Portadores de Fármacos , Composição de Medicamentos , Microesferas , Tamanho da Partícula
11.
AAPS PharmSciTech ; 20(6): 228, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227940

RESUMO

In order to obtain sustained release of biodegradable microspheres, the purpose of this study was to design and characterize an injectable octreotide microsphere-gel composite system. The octreotide microspheres were prepared by phase separation method, which used PLGA as a carrier material, dimethyl silicone oil as a phase separation reagent, and n-heptane-Span 80 as a hardener. In addition, we used poloxamer 407 (PL 407) and poloxamer 188 (PL 188) as the thermosensitive gel matrix material. The composite system was obtained by scattering octreotide microspheres in a poloxamer gel. In vitro data showed that the release time of the composite system could last for about 50 days. Because of the blocking and control actions of the poloxamer gel, the initial burst release was significantly reduced and the plateau phase was eliminated. Pharmacokinetic data showed that the burst release of the composite system was significantly less than that of the microspheres, i.e., Cmax1 was reduced by about half. From day 2 to day 50, higher plasma concentration levels and more stable drug release behavior were exhibited. In addition, the good biocompatibility of the composite system in vivo was also demonstrated by hematoxylin-eosin (HE) staining. Therefore, the octreotide microsphere-gel composite system will be a new direction for hydrophilic polypeptide/protein-loaded sustained release dosage forms with high pharmacological activity.


Assuntos
Géis/química , Microesferas , Octreotida/administração & dosagem , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/administração & dosagem , Animais , Liberação Controlada de Fármacos , Masculino , Octreotida/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos , Ratos Sprague-Dawley
12.
Water Sci Technol ; 79(8): 1484-1493, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31169506

RESUMO

A novel adsorbent, composed of cross-linked de-esterified pectin microspheres, was prepared via cross-linking with Ca(II) and modification by de-esterified pectin, low-methoxyl pectin (LMP) and pectic acid (PA). Fourier transform infrared (FTIR), energy dispersive spectrometry (EDS), scanning electron microscopy (SEM) and atomic absorption spectroscopy (AAS) were applied too, exhibiting a successful fabrication, good adsorption ability, and well-defined surface microstructure beneficial to Pb(II) adsorption. The adsorption ability of pectin microspheres (PMs), low-methoxyl pectin microspheres (LMPMs) and pectic acid microspheres (PAMs) for Pb(II) in aqueous solution were explored. The maximum adsorption capacity of PMs, LMPMs and PAMs was 127 mg·g-1, 292 mg·g-1 and 325 mg·g-1 at pH 5.0 respectively, indicating a great improvement of LMPMs and PAMs in the adsorption ability for Pb(II) compared with PMs. Furthermore, the adsorption mechanism was proposed. The experimental data were well fitted with pseudo-second-order kinetic and Langmuir isotherm models. Five-cycle reusability tests demonstrated that microspheres could be used repeatedly. All the results confirmed that LMPMs and PAMs, which presented outstanding adsorption capability and reusability, could be a good candidate for wastewater purification.


Assuntos
Cálcio/química , Chumbo/química , Microesferas , Pectinas/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias
13.
Pharm Res ; 36(8): 119, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31165279

RESUMO

PURPOSE: The purpose of this study was to characterize and detail the mechanism of a smart Ca2+ release depot (Ca3(PO4)2) about its ability for sustainable inhibition on peptide acylation within PLGA microspheres. METHODS: The octreotide acetate release and acylation kinetics were analyzed by RP-HPLC. Changes of Ca2+ concentration and adsorption behavior were determined by a Calcium Colorimetric Assay Kit. The inner pH changes were delineated by a classic pH sensitive probe, Lysosensor yellow/ blue® dextran. Morphological changes of microspheres, adsorption between polymer and additive, transformation of Ca3(PO4)2 were characterized using SEM, FTIR and SSNMR separately. RESULTS: Before and after microspheres formulation, the property and effectiveness of Ca3(PO4)2 were investigated. Compared with a commonly used calcium salt (CaCl2), high encapsulation efficiency (96.56%) of Ca3(PO4)2 guarantees lasting effectiveness. In an increasingly acidic environment that simulated polymer degradation, the poorly water-soluble Ca3(PO4)2 could absorb protons and transform into the more and more soluble CaHPO4 and Ca(H2PO4)2 to produce sufficient Ca2+ according to severity of acylation. The corresponding Ca2+ produce capacity fully met the optimum inhibition requirement since the real-time adsorption sites (water-soluble carboxylic acids) inside the degrading microspheres were rare. A sustained retention of three switchable calcium salts and slow release of Ca2+ were observed during the microsphere incubation. FTIR results confirmed the long-term inhibition effect induced by Ca3(PO4)2 on the adsorption between drug and polymer. CONCLUSIONS: With the presence of the smart Ca2+ depot (Ca3(PO4)2) in the microspheres, a sustainable and long-term inhibition of peptide acylation was achieved.


Assuntos
Cálcio/química , Microesferas , Peptídeos/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Acilação , Adsorção , Fosfatos de Cálcio/química , Cátions Bivalentes , Portadores de Fármacos , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Cinética , Octreotida/química , Prótons , Solubilidade , Eletricidade Estática , Água/química
14.
J Environ Manage ; 246: 174-183, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31176979

RESUMO

In this paper, hollow gangue microspheres (GM) were introduced into a geopolymer matrix through a geopolymeric method; our aim was to synthesize a green and low-cost adsorbent (GM/KGP) for the removal of heavy metal ions (Cu2+, Cd2+, Zn2+, and Pb2+) from aqueous solutions. We investigated the microstructure of the GM/KGP adsorbent, as well as the effects of adsorbent dose, time, and temperature on adsorption behavior; moreover, an adsorption mechanism was proposed. The GM/KGP adsorbent possessed a typical broad amorphous structure and abundant O-containing functional groups on its surface. The adsorption of Cu2+, Cd2+, Zn2+, and Pb2+ onto the GM/KGP adsorbent fitted well to the pseudo-second-order kinetic model, while the equilibrium isotherm adsorption data were fitted well to the Langmuir equation. The adsorption mechanism GM/KGP was attributed to physical, chemical, and electrostatic attractions, as well as to ion exchange. We conclude that this novel adsorbent has great potential in removing heavy metal ions from contaminated wastewater.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Microesferas , Águas Residuárias
15.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(6): 750-755, 2019 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-31198005

RESUMO

Objective : To summarize the research progress of controlled release of angiogenic factors and osteogenic factors in bone tissue engineering. Methods: The domestic and abroad literature on the controlled release structure of growth factors during bone regeneration in recent years was extensively reviewed and summarized. Results: The sustained-release structure includes direct binding, microsphere-three-dimensional scaffold structure, core-shell structure, layer self-assembly, hydrogel, and gene carrier. A sustained-release system composed of different sustained-release structures combined with different growth factors can promote bone regeneration and angiogenesis. Conclusion : Due to its controllability and persistence, the growth factor sustained-release system has become a research hotspot in bone tissue engineering and has broad application prospects.


Assuntos
Regeneração Óssea , Engenharia Tecidual , Preparações de Ação Retardada , Microesferas , Osteogênese
16.
Pharm Res ; 36(9): 127, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31236836

RESUMO

PURPOSE: Paclitaxel (PTX)-loaded genipin-crosslinked gelatin microspheres (GP-MS) are a prolonged IP delivery system under development for the treatment of peritoneal minimal residual disease (pMRD). Here, we show the use of a pharmacokinetic-pharmacodynamic (PKPD) modelling approach to inform the formulation development of PTX-GP-MS in a mice pMRD model. METHODS: PTX blood concentrations and survival data were obtained in Balb/c Nu mice receiving different single IP doses (7.5 and/or 35 mg/kg) of PTX-ethanolic loaded GP-MS (PTXEtOH-GP-MS), PTX-nanosuspension loaded GP-MS (PTXnano-GP-MS), and immediate release formulation Abraxane®. A population PK model was developed to characterize the PTX blood concentration pattern and to predict PTX concentrations in peritoneum. Afterwards, PKPD relationships between the predicted peritoneal or blood concentrations and survival were explored using time-to-event modelling. RESULTS: A PKPD model was developed that simultaneously describes the competing effects of treatment efficacy (driven by peritoneal concentration) and toxicity (driven by blood concentration) of PTX on survival. Clear survival advantages of PTXnano-GP-MS over PTXEtOH-GP-MS and Abraxane® were found. Simulations of different doses of PTXnano-GP-MS demonstrated that drug-induced toxicity is high at doses between 20 and 35 mg/kg. CONCLUSIONS: The model predicts that the dose range of 7.5-15 mg/kg of PTXnano-GP-MS provides an optimal balance between efficacy and safety.


Assuntos
Paclitaxel Ligado a Albumina/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Neoplasias Peritoneais/tratamento farmacológico , Paclitaxel Ligado a Albumina/química , Paclitaxel Ligado a Albumina/farmacocinética , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacocinética , Linhagem Celular Tumoral , Reagentes para Ligações Cruzadas/química , Portadores de Fármacos , Gelatina/química , Humanos , Iridoides/química , Camundongos Endogâmicos BALB C , Camundongos Nus , Microesferas , Modelos Biológicos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Adv Mater ; 31(33): e1901071, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31168915

RESUMO

Minimally invasive transcatheter embolization is a common nonsurgical procedure in interventional radiology used for the deliberate occlusion of blood vessels for the treatment of diseased or injured vasculature. A wide variety of embolic agents including metallic coils, calibrated microspheres, and liquids are available for clinical practice. Additionally, advances in biomaterials, such as shape-memory foams, biodegradable polymers, and in situ gelling solutions have led to the development of novel preclinical embolic agents. The aim here is to provide a comprehensive overview of current and emerging technologies in endovascular embolization with respect to devices, materials, mechanisms, and design guidelines. Limitations and challenges in embolic materials are also discussed to promote advancement in the field.


Assuntos
Materiais Biocompatíveis/química , Embolização Terapêutica/métodos , Animais , Embolização Terapêutica/instrumentação , Procedimentos Endovasculares , Humanos , Metais/química , Microesferas , Polímeros/química
18.
Oncol Res ; 27(5): 583-592, 2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31053181

RESUMO

This study evaluated the difference in treatment response and survival profiles between drug-eluting bead transarterial chemoembolization (DEB-TACE) and conventional transarterial chemoembolization (cTACE) treatments in Chinese hepatocellular carcinoma (HCC) patients. A total of 120 HCC patients were consecutively enrolled in this prospective cohort study, which showed that DEB-TACE achieved higher complete response (CR) (30.8%) compared with cTACE (7.4%) with no difference in overall response rate (ORR) for patients treated with DEB-TACE and cTACE (80.8% vs. 73.5%). In addition, DEB-TACE was associated with a lower rate of progressive disease (PD) compared with cTACE (1.9% vs. 11.8%). With respect to survival, patients in the DEB-TACE group achieved median progression-free survival (PFS) of 15 months (95% CI 12-18 months), which was longer than the cTACE group [median PFS 11 months (95% CI 10-12 months)]. Median overall survival (OS) was also longer with DEB-TACE [25 months (95% CI 22-28 months)] when compared with cTACE [21 months (95% CI 18-24 months)]. Univariate and multivariate logistic regression analysis showed that DEB-TACE was an independent predictive factor for achieving CR. Univariate Cox's regression analysis revealed that DEB-TACE was a predictive factor for prolonged PFS and OS, while multivariate analysis demonstrated that DEB-TACE was not an independent factor for predicting PFS or OS. In conclusion, we found that DEB-TACE achieved higher treatment response and prolonged survival compared with cTACE in Chinese HCC patients.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Quimioembolização Terapêutica , Neoplasias Hepáticas/tratamento farmacológico , Microesferas , Idoso , China , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento
19.
Carbohydr Polym ; 216: 167-179, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31047053

RESUMO

In this paper, acid-catalyzed conversion of nine sugars (xylose, glucose, fructose, galactose, sucrose, maltose, lactose, raffinose, and ß-cyclodextrin) with different sizes, steric structures and functionalities were investigated and impacts of the varied sugars on structures of resulting polymers were focused. Under similar reaction conditions, the yields of the carbon materials (insoluble polymers) formed followed the order: xylose ¼ lactose > galactose > ß-cyclodextrin > maltose > sucrose > fructose > glucose > raffinose. Increasing temperature enhanced transformation of soluble oligomers into insoluble ones. Morphologies of the carbon materials were closely related to sugar structures. Diameters of carbon materials (microsphere form) obtained from the disaccharides and oligosaccharides were larger than that of monosaccharides. Furthermore, the microspheres from oligosaccharides had a higher affinity to each other, resulting from continued polymerization as some reactive functionalities were retained in carbon materials. In addition, graphite structure was formed in the carbon materials, even at 160 °C.


Assuntos
Monossacarídeos/química , Oligossacarídeos/química , Polímeros/química , beta-Ciclodextrinas/química , Catálise , Hidrólise , Microesferas , Estrutura Molecular , Polímeros/síntese química , Solubilidade , Ácidos Sulfúricos/química , Temperatura Ambiente
20.
Eur J Pharm Sci ; 135: 12-21, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31067496

RESUMO

Among the factors that influence adherence to medication within the pediatric population, taste/irritation has been identified as a critical barrier to patient compliance. With the goal of improving compliance, microspheres (matrix systems within which the drug is dispersed) can be coated with a reverse enteric polymer that will prevent the release of the drug in the oral cavity while maintaining an immediate release once the drug product reaches the stomach, thereby achieving a taste neutral profile. In this work, the in-line performance of three process analytical technology (PAT) tools is evaluated in order to monitor the microsphere coating process. These tools are Raman spectroscopy, near-infrared spectroscopy and focused beam reflectance measurements, together with process data and raw material attributes. The ability of these different sources of information to predict the coating's barrier performance is evaluated by using a combined-data-approach: multiblock partial least squares (MBPLS). Results show that Raman spectroscopy has a superior predictive performance and that it has the potential to monitor the coating process of the microspheres as well as to detect process discrepancies (such as spray rate changes), demonstrating its usefulness for the monitoring of fluid bed coating processes. It was also demonstrated that Raman can be used to clearly differentiate batches with significantly difference in-vitro dissolution performance. This monitoring is considered critical to ensure consistent coating performance for this thin film barrier membrane that is essential to patient compliance.


Assuntos
Portadores de Fármacos/química , Microesferas , Polímeros/química , Antioxidantes/química , Preparações de Ação Retardada , Composição de Medicamentos , Humanos , Permeabilidade , Solubilidade , Espectroscopia de Luz Próxima ao Infravermelho , Análise Espectral Raman , Propriedades de Superfície , Tecnologia Farmacêutica
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