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1.
BMC Pregnancy Childbirth ; 23(1): 337, 2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37170216

RESUMEN

BACKGROUND: Cesarean scar pregnancy (CSP) refers to the implantation and growth of the gestational sac at a uterine scarring site due to a previous cesarean section. The effects of CSP on subsequent fertility have emerged as a clinical issue of importance in gynecology and obstetrics in China owing to the increasing rate of cesarean section over the past 30 years in combination with the abolition of the national family planning policy, allowing for subsequent pregnancies. Therefore, we aimed to investigate the effects of CSP treatment on subsequent fertility and pregnancy outcomes. METHODS: The study consecutively enrolled 499 women treated for CSP at Taizhou Hospital between January 2009 and December 2018. The study outcomes were the rate of secondary infertility and pregnancy outcomes. Clinical information was collected at the time of admission for CSP treatment. Information on subsequent fertility and pregnancy outcomes was collected via telephonic follow-up. RESULTS: Among the 499 women who met the inclusion criteria for CSP, 48 were lost to follow-up. Most women (74.9%, 338/451) did not express the desire for a subsequent pregnancy after CSP treatment. Among the 113 women who initially desired a subsequent pregnancy, 62 finally abandoned fertility plans. Among the 51 women who pursued pregnancy, 48 pregnancies were recorded in 43 women, infertility secondary to CSP treatment was identified in 15.7% (8/51) of women, and 60.8% (31/51) of women achieved full-term pregnancy, with placenta accreta spectrum identified in two women, one requiring a hysterectomy during cesarean section due to massive bleeding. Among the 16 women treated with uterine artery embolization combined with uterine aspiration and 18 women treated by ultrasound-guided local lauromacrogol injection combined with uterine aspiration, a successful full-term pregnancy rate of 68.8% (11/16) and 88.9% (16/18), respectively, was achieved. There were five cases of recurrent CSP among all 76 pregnancies (6.6%). CONCLUSION: Over a long-term follow-up of women after CSP treatment, a high successful fertility rate was identified, with also an increased CSP recurrence rate. Uterine artery embolization combined with uterine aspiration and ultrasound-guided local lauromacrogol injection combined with uterine aspiration showed high rates of successful post-treatment fertility and pregnancy.


Asunto(s)
Infertilidad , Embarazo Ectópico , Embarazo , Femenino , Humanos , Cesárea/efectos adversos , Estudios Retrospectivos , Cicatriz/complicaciones , Polidocanol , Embarazo Ectópico/etiología , Embarazo Ectópico/terapia , Resultado del Embarazo , Fertilidad
2.
Clin Oral Investig ; 27(7): 4051-4059, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37133698

RESUMEN

OBJECTIVES: Surface reaction-type pre-reacted glass-ionomer (S-PRG) filler releases six types of ions with a neutralizing ability. This study evaluated the effect of S-PRG filler incorporation in an H2O2-based bleaching material on the bleaching efficacy, pH, and reaction state. MATERIALS AND METHODS: The experimental bleaching material was formulated by the addition of 5% or 10% S-PRG fillers to the powder part. The stained bovine teeth were treated with the prepared bleaching paste. Commission internationale de l'éclairage (CIE) L*a*b* color space values were recorded before and after bleaching, and the color difference (ΔE) and whiteness index (WID) were calculated. Moreover, the used bleaching formulations were assessed for their pH values and reaction state by evaluating the oxidation state of manganese (Mn+2) using electron spin resonance (ESR). RESULTS: The results of ΔE and WID showed that the addition of S-PRG filler increased the bleaching effect, but there was no significant difference between the groups with 5% and 10% S-PRG filler. A significant increase in pH in S-PRG filler groups (5% pH 6.7, 10% pH 6.8) was found compared to the 0% group (pH 4.8). ESR measurements showed that the signal emitted from Mn+2 decreased over time. The S-PRG filler groups showed a significantly higher reduction in Mn+2 compared to the 0% group, with no significant difference between the 5% and 10% S-PRG groups. CONCLUSIONS: S-PRG filler addition resulted in improved bleaching efficacy, higher reaction rate, and pH values that are close to neutral. CLINICAL RELEVANCE: S-PRG filler addition may be effective on the bleaching outcome of H2O2-based materials.


Asunto(s)
Cementos de Ionómero Vítreo , Peróxido de Hidrógeno , Animales , Bovinos , Espectroscopía de Resonancia por Spin del Electrón , Ácido Hipocloroso , Concentración de Iones de Hidrógeno
3.
J Environ Manage ; 329: 117072, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36584516

RESUMEN

Safe and green disposal or utilization of sewage sludge (SS) has attracted significant attention as SS is increasingly produced worldwide and emerges as an environmental burden if without proper treatment. In this study, efficient and sustainable treatment of SS was achieved using plasma-electrolytic liquefaction (PEL) with alkaline catalysts including sodium hydroxide (NaOH), sodium carbonate (Na2CO3), and sodium acetate (NaAc) and renewable solvents including polyethylene glycol (PEG) 200 and glycerol. Furthermore, the obtained bio-oil with abundant hydroxyl groups could partially replace polyols derived from fossil energy to synthesize bio-based polyurethane foams (BPUFs) for oil adsorption. The results showed that the Na2CO3 catalyst exhibited better performance and yielded bio-oil with a higher heating value (HHV) of 26.26 MJ/kg, very low nitrogen content (0.14%) and metal ions, and a nearly neutral pH of 7.41, under the optimized conditions. Compared with conventional oil bath liquefaction, PEL can significantly improve the liquefaction efficiency, promote the transfer of metal ions in SS to the solid residue (SR), and facilitate the transfer of nitrogen to the gas phase and SR, thereby upgrading the bio-oil to a certain extent. The BPUFs showed excellent oil adsorption capacity, reusability, and desorption and can play an important role in combating oil spills. The PEL method may provide a green avenue for SS valorization and the comprehensive utilization of the obtained products.


Asunto(s)
Poliuretanos , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Biocombustibles , Iones , Metales/análisis , Poliuretanos/química , Aguas del Alcantarillado/química , Temperatura , Eliminación de Residuos Líquidos/métodos
4.
Odontology ; 109(4): 828-835, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33991277

RESUMEN

The purpose is to evaluate the effect of photo-thermal acceleration on in-office bleaching efficiency using a bleaching agent without photocatalysts in vitro. Artificially discolored bovine lower incisors were prepared, and the mixed in-office bleaching material contained hydrogen peroxide 23% was applied by following treatment for 10 min: high-(HI group) and low-intensity LED lights (LI group), oven at 38 °C (OV group), and room temperature at 23 °C (RT group). Color was measured before and after bleaching and color difference (∆E*) was calculated. The data were statistically analyzed using a two-way ANOVA and Tukey's post hoc test. The temperature change (∆T) of applied bleaching agent in HI and LI groups was measured using a thermography and was analyzed using a T test. The bleaching procedures were repeated 6 times. Irradiation in the HI group resulted in the highest ΔE, followed by the LI group whose ΔE was significantly lower. Both irradiated modes exhibited higher ΔE compared to non-irradiated OV and RT groups which were not significantly different from each other. The average temperature rise of bleaching agents in HI and LI groups after 10 min irradiation was 15.00 °C and 11.80 °C, respectively. The effect of photo-thermal acceleration was proved for an in-office bleaching agent without photocatalysts in vitro.


Asunto(s)
Blanqueadores Dentales , Blanqueamiento de Dientes , Aceleración , Animales , Bovinos , Color , Peróxido de Hidrógeno
5.
J Virol ; 93(7)2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30700601

RESUMEN

The presence of sequence divergence through adaptive mutations in the major capsid protein VP1, and also in VP0 (VP4 and VP2) and VP3, of foot-and-mouth disease virus (FMDV) is relevant to a broad range of viral characteristics. To explore the potential role of isolate-specific residues in the VP0 and VP3 coding regions of PanAsia-1 strains in genetic and phenotypic properties of FMDV, a series of recombinant full-length genomic clones were constructed using Cathay topotype infectious cDNA as the original backbone. The deleterious and compensatory effects of individual amino acid substitutions at positions 4008 and 3060 and in several different domains of VP2 illustrated that the chain-based spatial interaction patterns of VP1, VP2, and VP3 (VP1-3), as well as between the internal VP4 and the three external capsid proteins of FMDV, might contribute to the assembly of eventually viable viruses. The Y2079H site-directed mutants dramatically induced a decrease in plaque size on BHK-21 cells and viral pathogenicity in suckling mice. Remarkably, the 2079H-encoding viruses displayed a moderate increase in acid sensitivity correlated with NH4Cl resistance compared to the Y2079-encoding viruses. Interestingly, none of all the 16 rescued viruses were able to infect heparan sulfate-expressing CHO-K1 cells. However, viral infection in BHK-21 cells was facilitated by utilizing non-integrin-dependent, heparin-sensitive receptor(s) and replacements of four uncharged amino acids at position 3174 in VP3 of FMDV had no apparent influence on heparin affinity. These results provide particular insights into the correlation of evolutionary biology with genetic diversity in adapting populations of FMDV.IMPORTANCE The sequence variation within the capsid proteins occurs frequently in the infection of susceptible tissue cultures, reflecting the high levels of genetic diversity of FMDV. A systematic study for the functional significance of isolate-specific residues in VP0 and VP3 of FMDV PanAsia-1 strains suggested that the interaction of amino acid side chains between the N terminus of VP4 and several potential domains of VP1-3 had cascading effects on the viability and developmental characteristics of progeny viruses. Y2079H in VP0 of the indicated FMDVs could affect plaque size and pathogenicity, as well as acid sensitivity correlated with NH4Cl resistance, whereas there was no inevitable correlation in viral plaque and acid-sensitive phenotypes. The high affinity of non-integrin-dependent FMDVs for heparin might be explained by the differences in structures of heparan sulfate proteoglycans on the surfaces of different cell lines. These results may contribute to our understanding of the distinct phenotypic properties of FMDV in vitro and in vivo.


Asunto(s)
Sustitución de Aminoácidos/genética , Proteínas de la Cápside/genética , Virus de la Fiebre Aftosa/genética , Fiebre Aftosa/virología , Animales , Células CHO , Cricetulus , Heparitina Sulfato/genética , Ratones , Sistemas de Lectura Abierta/genética , Serogrupo , Virión/genética
6.
Microb Pathog ; 120: 37-41, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29704670

RESUMEN

Periodontitis is a highly prevalent infective and inflammatory disease with an adverse impact on systemic health. Isorhamnetin, a flavonoid mainly isolated from Hippophae fhamnoides L. fruit, has been reported to have anti-inflammatory effect. This study aimed to investigate the anti-inflammatory effects and mechanism of isorhamnetin on lipopolysaccharide (LPS)-induced inflammatory response in human gingival fibroblasts (HGFs). The production of inflammatory mediators and the expression of proteins were measured by ELISA and western blot analysis. The results demonstrated that isorhamnetin attenuated LPS-induced release of PGE2, NO, IL-6, and IL-8 in HGFs. Isorhamnetin also inhibited LPS-induced NF-κB activation. The expression of Nrf2 and HO-1 were up-regulated by treatment of isorhamnetin. Furthermore, knockdown of Nrf2 by siRNA reversed the anti-inflammatory effects of isorhamnetin. In conclusion, these results suggested that isorhamnetin inhibited LPS-induced inflammation in HGFs by activating Nrf2 signaling pathway.


Asunto(s)
Antiinflamatorios/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Encía/metabolismo , Lipopolisacáridos/efectos adversos , Factor 2 Relacionado con NF-E2/metabolismo , Quercetina/análogos & derivados , Transducción de Señal/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Dinoprostona/metabolismo , Hemo-Oxigenasa 1/metabolismo , Humanos , Inflamación/tratamiento farmacológico , Interleucina-6/metabolismo , Interleucina-8/metabolismo , FN-kappa B/metabolismo , Periodontitis , Quercetina/farmacología
7.
Environ Sci Technol ; 52(10): 5812-5820, 2018 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29660985

RESUMEN

Aquatic ecosystems and human health have been seriously threatened by illegal discharge of wastewater, while simple and effective monitoring methods are still sparse. Here, we propose a facile method for on-site pollutant monitoring by surface-enhanced Raman spectroscopy with a novel substrate. This substrate is fabricated by interface self-assembly of Au@Ag nanocubes (NCs) on a simultaneously formed polyvinyl chloride (PVC) template, followed by coating with a thin Au film. The Au@Ag@Au-NCs/PVC film is flexible, ultralight, and robust and could float on the surface of water and firmly contact with water even under harsh environmental conditions. Moreover, the Au@Ag@Au-NCs/PVC film is translucent, allowing penetration of laser beams and enhancement of Raman signals. When thiram was used as a model contaminant in aqueous solution, a good linear relationship ( R2 = 0.972) was obtained over the range of 0.1-50 ppb with a detection limit of 0.1 ppb. Raman signals of thiram can be instantly and consecutively detected with the enhancement of the film in the simulated experiments, suggesting its possible use in the long run. Furthermore, the film can be easily regenerated by NaBH4 solution washing, which could reduce the operating cost. In summary, the Au@Ag@Au-NCs/PVC film has great potential in on-site pollutant monitoring in aqueous environments with a portable Raman spectrometer.


Asunto(s)
Contaminantes Ambientales , Nanopartículas del Metal , Contaminantes Químicos del Agua , Ecosistema , Oro , Humanos , Cloruro de Polivinilo , Plata , Espectrometría Raman
8.
Gynecol Obstet Invest ; 83(3): 306-312, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29208846

RESUMEN

OBJECTIVES: To evaluate the efficacy of ultrasound-guided local lauromacrogol injection combined with aspiration for treating cesarean scar pregnancy (CSP). METHODS: From July 2016 to December 2016, 18 patients diagnosed with CSP were treated with ultrasound-guided local lauromacrogol injection combined with aspiration. Clinical data and outcome were analysed. RESULTS: All patients were treated successfully. The amount of bleeding ranged between 10 and 50 mL. The duration of hospitalization ranged between 2 and 11 days. Serum ß-human chorionic gonadotropin (ß-hCG) decreased to the nondetectable level within 19-41 days. Menstruation recovery occurred after 10-24 days of normalization of serum ß-hCG level. Reproductive functions were preserved, and there were no untoward effects or complications. CONCLUSIONS: Ultrasound-guided local lauromacrogol injection combined with aspiration is an effective CSP therapy, as it was associated with a high success rate, short hospitalization and fast recovery. However, its wider application and popularization have to be validated on a larger patient population affected by CSP.


Asunto(s)
Cicatriz , Detergentes/administración & dosificación , Paracentesis/métodos , Polietilenglicoles/administración & dosificación , Embarazo Ectópico/terapia , Ultrasonografía Intervencional/métodos , Adulto , Cesárea/efectos adversos , Gonadotropina Coriónica Humana de Subunidad beta/sangre , Cicatriz/etiología , Femenino , Humanos , Polidocanol , Embarazo , Embarazo Ectópico/sangre , Embarazo Ectópico/etiología , Estudios Retrospectivos , Resultado del Tratamiento
9.
Drug Dev Ind Pharm ; 44(12): 1918-1923, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30027774

RESUMEN

Individualized medicine is a new direction in the field of modern pharmacy. In this study, we assessed the feasibility and accuracy of 3D printing techniques for the preparation of individualized doses of mouth-disintegrating tablets of warfarin. Warfarin sodium, D-sucrose, pregelatinized starch, povidone K30, microcrystalline cellulose, and silicon dioxide (at a ratio of 1:42.45:46.15:5.1:4.9:0.4) were mixed and used as the printing powder in the 3D printer; preset parameters were used. The dosage of the tablet was controlled by the number of printing layers. The content, dose uniformity, dose accuracy, hardness, friability, disintegration time, dissolution, and the microstructural and overall appearance were determined to evaluate the printed tablets. For the doses of 3, 2, and 1 mg that were produced in the experiment, the disintegration times were 50.0 ± 5.2, 35.7 ± 4.3, and 11.0 ± 2.2 s, respectively, and the relative errors of the dose were -2.33, -1.50, and 0%, respectively. The other indicators were consistent with the preparation requirements of pharmaceutical tablets. It is possible to prepare tablets with excellent properties and controlled drug doses by using 3D printing techniques. This technology will be an important means to achieve individualized medicine.


Asunto(s)
Anticoagulantes/química , Preparaciones de Acción Retardada/química , Composición de Medicamentos/métodos , Impresión Tridimensional , Warfarina/química , Administración Oral , Anticoagulantes/administración & dosificación , Química Farmacéutica , Preparaciones de Acción Retardada/administración & dosificación , Composición de Medicamentos/instrumentación , Liberación de Fármacos , Excipientes/química , Estudios de Factibilidad , Humanos , Comprimidos , Warfarina/administración & dosificación
10.
J Sep Sci ; 40(12): 2629-2637, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28453223

RESUMEN

Nano-sized molecularly imprinted polymers for tiliroside were successfully prepared by a precipitation polymerization method. Acrylamide, ethylene glycol dimethacrylate, azobisisobutyronitrile, and acetonitrile/dimethyl sulfoxide were used as functional monomer, cross-linker, initiator, and porogen, respectively. The structural features and morphological characterization of tiliroside-imprinted polymers were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The adsorption experiments indicated that the tiliroside-imprinted polymers exhibited high selective recognition property to tiliroside. Scatchard analysis indicated that the homogeneous-binding sites were formed in the polymers. The selectivity test revealed that the adsorption capacity and selectivity of polymers to tiliroside was significantly higher than that of rutin, astragalin, and kaempferol. Finally, the tiliroside-imprinted polymers were employed as adsorbents in solid-phase extraction for the extraction of tiliroside from the ethyl acetate extract of the flowers of Edgeworthia gardneri (wall.) Meisn. The results demonstrated that the extraction recoveries of tiliroside ranged from 69.3 to 73.5% by using tiliroside-imprinted polymers coupled with solid-phase extraction method. These results indicated that the tiliroside-based molecularly imprinted solid-phase extraction method was proven to be an effective technique for the separation and enrichment of tiliroside from natural medicines.


Asunto(s)
Flavonoides/aislamiento & purificación , Flores/química , Impresión Molecular , Thymelaeaceae/química , Adsorción , Cromatografía Líquida de Alta Presión , Polímeros , Extracción en Fase Sólida
11.
Pharm Res ; 32(7): 2310-7, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25585955

RESUMEN

PURPOSE: For long-effective peptide formulation based on poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres, acylation often leads to peptide instability during its release and reduced drug efficacy. Among the reported solving strategies, adding dication such as Ca(2+) and Mn(2+) in the formulation was the most convenient method for inhibiting basic peptide acylation. However, the strategies for the acidic peptide still remain unexplored, possibly due to the peptide's changeable charge state in acid environment within degraded PLGA microspheres. Moreover, the previous studies mainly focusing on the macroscopical adsorption of peptide to PLGA cannot demonstrate the inhibition mechanism. METHODS: Acylation inhibition for acidic peptide (exenatide) by dications (Ca(2+), Mn(2+) and Zn(2+)) was studied for the first time, and Quartz Crystal Microbalance with Dissipation (QCM-D) was innovatively employed to analyze microcosmic mechanism of the inhibition. RESULTS: These dications played different roles in acylation inhibition of acidic peptide. The effects of dications on acylation outside or inside PLGA microspheres indicated that Ca(2+) did not work, Mn(2+) played a weak role, and Zn(2+) possessed the greatest inhibition. CONCLUSIONS: Zn(2+) was the most effective dication for the acylation inhibition because of the complex formation and its steric-hindrance effect, which was a new function for this dication.


Asunto(s)
Cationes Bivalentes/química , Portadores de Fármacos/química , Excipientes/química , Ácido Láctico/química , Péptidos/química , Ácido Poliglicólico/química , Ponzoñas/química , Acilación , Química Farmacéutica , Composición de Medicamentos , Liberación de Fármacos , Estabilidad de Medicamentos , Exenatida , Microesferas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Solubilidad
12.
Langmuir ; 30(24): 7052-6, 2014 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-24898350

RESUMEN

Various aspects of particle-stabilized emulsions (or so-called Pickering emulsions) have been extensively investigated during the last two decades, but the preparation of uniform Pickering emulsion droplets via a simple and scalable method has been sparingly realized. We report the preparation of uniform Pickering emulsions by Shirasu porous glass (SPG) membrane emulsification. The size of the emulsion droplets ranging from 10-50 µm can be precisely controlled by the size of the membrane pore. The emulsion droplets have a high monodispersity with coefficients of variation (CV) lower than 15% in all of the investigated systems. We further demonstrate the feasibility of locking the assembled particles at the interface, and emulsion droplets have been shown to be excellent templates for the preparation of monodisperse colloidosomes that are necessary in drug-delivery systems.


Asunto(s)
Emulsiones/química , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Membranas Artificiales
13.
Pharm Res ; 31(6): 1566-74, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24398695

RESUMEN

PURPOSE: It is well known that primary emulsion (W1/O) preparation process (by ultrasonication or homogenization) plays an important role in the properties of drug-loaded microspheres, such as encapsulation efficiency, release behavior and pharmacodynamics. However, its involved mechanism has not been intensively and systematically studied, partly because that broad size distribution of the resultant particles prepared by conventional preparation can greatly disturb the analysis and reliability of the results. Here, we focused on the relevant studies. METHODS: In order to eliminate the disturbance caused by broad size distribution, uniform-sized exenatide-loaded poly(DL-lactic-co-glycolic acid) (PLGA) microspheres were prepared by Shirasu Porous Glass (SPG) premix membrane emulsification. The properties of microspheres whose W1/O was formed by ultrasonication (UMS) and homogenization (HMS) were compared including in vitro release, pharmacology and so forth. RESULTS: HMS exhibited fast release rate and hyperglycemic efficacy within first 14 days, but declined afterwards. Comparatively, UMS showed slower polymer degradation, more acidic microclimate pH (µpH) in vitro, and stable drug release with sustained efficacy during 1 month in vivo. CONCLUSIONS: HMS was desirable for the 2-week-sustained release in vivo, while UMS was more appropriate for the longer time release (about 1 month). These comparative researches can provide guidance for emulsion-microsphere preparation routs in pharmaceutics.


Asunto(s)
Hipoglucemiantes/química , Péptidos/química , Ponzoñas/química , Animales , Composición de Medicamentos , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Emulsiones , Excipientes , Exenatida , Concentración de Iones de Hidrógeno , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/farmacocinética , Ácido Láctico , Masculino , Microesferas , Tamaño de la Partícula , Péptidos/administración & dosificación , Péptidos/farmacocinética , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Ratas Sprague-Dawley , Ponzoñas/administración & dosificación , Ponzoñas/farmacocinética
14.
Chemosphere ; 350: 141186, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38215833

RESUMEN

Increased use of bioplastics, such as polylactic acid (PLA), helps in reducing greenhouse gas emissions, decreases energy consumption and lowers pollution, but its degradation efficiency has much room for improvement. The degradation rate of electrospun PLA fibers of varying diameters ranging from 0.15 to 1.33 µm is measured during hydrolytic degradation under different pH from 5.5 to 10, and during aerobic biodegradation in seawater supplemented with activated sewage sludge. In hydrolytic conditions, varying PLA fiber diameter had significant influence over percentage weight loss (W%L), where faster degradation was achieved for PLA fibers with smaller diameter. W%L was greatest for PLA-5 > PLA-12 > PLA-16 > PLA-20, with average W%L at 30.7%, 27.8%, 17.2% and 14.3% respectively. While different pH environment does not have a significant influence on PLA degradation, with W%L only slightly higher for basic environments. Similarly biodegradation displayed faster degradation for small diameter fibers with PLA-5 attaining the highest degree of biodegradation at 22.8% after 90 days. Hydrolytic degradation resulted in no significant structural change, while biodegradation resulted in significant hydroxyl end capping products on the PLA surface. Scanning electron microscopy (SEM) imaging of degraded PLA fibers showed a deteriorated morphology of PLA-5 and PLA-12 fibers with increased adhesion structures and irregularly shaped fibers, while a largely unmodified morphology for PLA-16 and PLA-20.


Asunto(s)
Poliésteres , Poliésteres/química , Hidrólisis , Microscopía Electrónica de Rastreo
15.
Adv Clin Exp Med ; 32(3): 349-356, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36421043

RESUMEN

BACKGROUND: Orthodontic tooth movement is linked to alveolar bone reconstruction. OBJECTIVES: As a regulator of cell proliferation, insulin-like growth factor 1 (IGF-1) plays an important role in osteoporotic fracture healing. This study aims to investigate the effect of IGF-1 on alveolar bone remodeling in diabetic rats. MATERIAL AND METHODS: Sprague Dawley (SD) rats were randomly divided into 3 groups, including a control group, a model group established with streptozotocin (STZ) injection to prepare the diabetic rats (type 1 diabetes), and an IGF-1 group of diabetic rats receiving daily intraperitoneal injections of 1.0 mg/kg IGF-1. Nickel-titanium coil springs were used to pull the first molar forward to establish the model. The maxillary first to third molars and the surrounding alveolar bone were collected to measure tooth movement distance. Hematoxylin and eosin (H&E) staining was applied to detect the pathological changes in the periodontal tissue. Real-time polymerase chain reaction (PCR) and western blot were adopted to measure bone morphogenetic protein 2 (BMP-2) mRNA and protein expression. Enzyme-linked immunosorbent assays (ELISAs) were used to measure interleukin-1α (IL-1α) levels in the serum. RESULTS: The tooth movement distance was significantly decreased, BMP-2 expression was downregulated, and IL-lα levels were enhanced in the model group compared to the control group (p < 0.05). However, the tooth movement distance was increased, BMP-2 expression was increased, and IL-lα levels were reduced in the IGF-1 group compared to the model group (p < 0.05). Hematoxylin and eosin staining showed that alveolar bone destruction was attenuated in the IGF-1 group, while the new bone was not active in the model group. CONCLUSIONS: Diabetes can damage alveolar bone remodeling in orthodontic tooth movement. The IGF-1 promotes alveolar bone remodeling by inhibiting inflammation and upregulating BMP-2 expression.


Asunto(s)
Diabetes Mellitus Experimental , Factor I del Crecimiento Similar a la Insulina , Ratas , Animales , Ratas Sprague-Dawley , Técnicas de Movimiento Dental , Proteína Morfogenética Ósea 2/farmacología , Eosina Amarillenta-(YS)/farmacología , Hematoxilina/farmacología , Remodelación Ósea
16.
Mater Horiz ; 10(11): 4882-4891, 2023 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-37602807

RESUMEN

Double-network (DN) gels are unique mechanochemical materials owing to their structures that can be dynamically remodelled during use. The mechanical energy applied to DN gels is efficiently transferred to the chemical bonds of the brittle network, generating mechanoradicals that initiate the polymerisation of pre-loaded monomers, thereby remodelling the materials. To attain continuous remodelling or growth in response to repetitive mechanical stimuli, a sustainable supply of chemical reagents to such dynamic materials is essential. In this study, inspired by the vascular perfusion transporting nutrients to cells, we constructed a circulatory system for a continuous supply of chemicals to channel-containing DN hydrogels (c-DN gels). The perfusion of monomer solutions through the channel and permeability of the c-DN gels not only replenishes the monomers consumed by the polymerisation but also replenishes the water loss caused by the surface evaporation of hydrogel, thereby freeing the mechanochemical process of DN gels from the constraints of the underwater environment. The facile chemical supply enabled us to modulate the mechanical enhancement of the c-DN gel and attain muscle-like strengthening under repeated mechanical training in deoxygenated air. We also studied the kinetics of polymer growth and strengthening and deciphered unique features of mechanochemical reaction in DN gels including the extremely long-living radicals and delayed mechanical strengthening.


Asunto(s)
Hidrogeles , Polímeros , Polímeros/química , Perfusión
17.
Langmuir ; 28(39): 13984-92, 2012 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-22937802

RESUMEN

The microcosmic mechanisms of protein (recombinant human growth hormone, rhGH) incomplete release and stability from amphiphilic poly(monomethoxypolyethylene glycol-co-D,L-lactide) (mPEG-PLA, PELA) microspheres were investigated. PELA with different hydrophilicities (PELA-1, PELA-2, and PELA-3) based on various ratios of mPEG to PLA were employed to prepare microspheres exhibiting a narrow size distribution using a combined double emulsion and premix membrane emulsification method. The morphology, rhGH encapsulation efficiency, in vitro release profile, and rhGH stability of PELA microspheres during the release were characterized and compared in detail. It was found that increasing amounts of PLA enhanced the encapsulation efficiency of PELA microspheres but reduced both the release rate of rhGH and its stability. Contact angle, atomic force microscope (AFM), and quartz crystal microbalance with dissipation (QCM-D) techniques were first combined to elucidate the microcosmic mechanism of incomplete release by measuring the hydrophilicity of the PELA film and its interaction with rhGH. In addition, the pH change within the microsphere microenvironment was monitored by confocal laser scanning microscopy (CLSM) employing a pH-sensitive dye, which clarified the stability of rhGH during the release. These results suggested that PELA hydrophilicity played an important role in rhGH incomplete release and stability. Thus, the selection of suitable hydrophilic polymers with adequate PEG lengths is critical in the preparation of optimum protein drug sustained release systems. This present work is a first report elucidating the microcosmic mechanisms responsible for rhGH stability and its interaction with the microspheres. Importantly, this research demonstrated the application of promising new experimental methods in investigating the interaction between biomaterials and biomacromolecules, thus opening up a range of exciting potential applications in the biomedical field including drug delivery and tissue regeneration.


Asunto(s)
Hormona de Crecimiento Humana/química , Ácido Láctico/química , Microesferas , Polietilenglicoles/química , Polímeros/química , Tensoactivos/química , Humanos , Tamaño de la Partícula , Poliésteres , Proteínas Recombinantes/química , Propiedades de Superficie
18.
J Mater Sci Mater Med ; 23(2): 375-84, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22139537

RESUMEN

Oleoyl-carboxymethy chitosan (OCMCS) nanoparticles based on chitosan with different molecular weights (50, 170 and 820 kDa) were prepared by self-assembled method. The nanoparticles had spherical shape, positive surface charges and the mean diameters were 157.4, 274.1 and 396.7 nm, respectively. FITC-labeled OCMCS nanoparticles were internalized via the intestinal mucosa and observed in liver, spleen, intestine and heart following oral deliverance to carps (Cyprinus carpio). Extracellular products (ECPs) of Aeromonas hydrophila as microbial antigen was efficiently loaded to form OCMCS-ECPs nanoparticles and shown to be sustained release in PBS. Significantly higher (P < 0.05) antigen-specific antibodies were detected in serum after orally immunized with OCMCS-ECPs nanoparticles than that immunized with ECPs alone and non-immunized in control group in carps. These results implied that amphiphilic modified chitosan nanoparticles had great potential to be applied as carriers for the oral administration of protein drugs.


Asunto(s)
Quitosano/análogos & derivados , Nanopartículas/química , Nanotecnología/métodos , Administración Oral , Aeromonas/metabolismo , Animales , Antiinfecciosos/farmacología , Antígenos/química , Materiales Biocompatibles/química , Carpas , Quitosano/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Luz , Ensayo de Materiales , Microscopía Electrónica de Transmisión/métodos , Peso Molecular , Solubilidad , Estrés Mecánico , Agua/química
19.
Fertil Steril ; 118(2): 407-413, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35691718

RESUMEN

OBJECTIVE: To study the efficacy of 3 treatment options for type 2 cesarean scar pregnancy (CSP) and establish an optimal treatment strategy for type 2 CSP. DESIGN: Retrospective cohort study. SETTING: A tertiary hospital. PATIENTS: The study examined 160 women with type 2 CSP. INTERVENTIONS: Ultrasound-guided vacuum aspiration after local injection of lauromacrogol, ultrasound-guided vacuum aspiration after uterine artery embolization (UAE), and transabdominal resection or hysteroscopy combined with laparoscopic resection. MAIN OUTCOME MEASURES: The success rates, duration of hospitalization, hospitalization cost, amount of blood loss, recovery time, and menstruation resuming after recovery. RESULTS: The success rates of the UAE, lauromacrogol, and surgical groups were 87.1%, 92.5%, and 95.5%, respectively, with no significant differences. The cost and duration of hospitalization in the lauromacrogol group were significantly lower than those in the UAE and surgical groups. Analysis of the causes of treatment failure revealed a significant difference in the gestational age. The area under the receiver operating characteristic curve was 0.660 (95% confidence interval, 0.533-0.788). When the gestational age was 48.5 days, Youden index was the highest. Furthermore, when the diagnostic thresholds were selected as 49, 56, and 63 days of pregnancy, the corresponding areas under the receiver operating characteristic curve were 0.652, 0.541, and 0.510, respectively. CONCLUSION: Ultrasound-guided vacuum aspiration after local injection of lauromacrogol is recommended for patients with type 2 CSP at <49 days of gestation. Laparotomy or laparoscopy combined with hysteroscopy is suitable for patients with gestation of >49 days, especially for those with >56 days of gestation.


Asunto(s)
Embarazo Ectópico , Embolización de la Arteria Uterina , Cesárea/efectos adversos , Gonadotropina Coriónica Humana de Subunidad beta , Cicatriz/diagnóstico por imagen , Cicatriz/etiología , Cicatriz/terapia , Femenino , Humanos , Polidocanol , Embarazo , Embarazo Ectópico/diagnóstico por imagen , Embarazo Ectópico/etiología , Estudios Retrospectivos , Resultado del Tratamiento , Embolización de la Arteria Uterina/efectos adversos
20.
Materials (Basel) ; 16(1)2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36614349

RESUMEN

This study investigated the effect of water sorption and bleaching on light transmission properties (Straight-light transmission (G0), Light diffusion (DF) and Amount of transmitted light (AV)) and translucency parameters (TP) of nano-filled flowable composites. A total of 35 composite disks (0.5 mm thickness) were prepared using A2 shade of 5 nanofiller composites (n = 7/each); Beautifil Flow Plus X F03 (SHOFU INC), Clearfil Majesty ES Flow (Kuraray Noritake Dental), Estelite Universal Flow (EUF, Tokuyama Dental), Estelite Flow Quick (Tokuyama Dental) and Filtek Supreme Ultra Flowable Restorative (FSU, 3M ESPE). Then, they were cured by LEDs (VALO, Ultradent) on standard mood (1000 mW/cm2) for 20 s. Samples were tested for straight-line transmission (G0), diffusion (DF), the amount of transmitted light (AV) and (TP) immediately after 24 h (dry storage), after 1-week water storage and after each of the three cycles of in-office bleaching (HiLite, SHOFU INC). Result: G0, DF, AV and TP were significantly affected by different materials (p < 0.001). The AV of FSU increased significantly after the 1-week water storage, then after the second bleaching cycle (p < 0.001). The TP for EUF slightly decreased (p = 0.019) after 1-week water storage, then increased throughout bleaching. Conclusion: Ageing/bleaching conditions do not affect G0, DF, AV and TP. The compositional variation between nano-filler composites resulted in a significant difference between materials.

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