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BACKGROUND: Although ultrasonography (US) has been widely used in the diagnosis of human diseases to monitor the progress of cystic echinococcosis (CE) control, the screening method for hepatic CE in sheep flocks requires adjustment. In this study, we used a US scanner to screen sheep flocks and evaluated the efficacy of dosing dogs once a year with praziquantel for 7 years from 2014 to 2021. METHODS: All sheep in the three flocks were screened using an ultrasound scanner in 2014 and compared with the prevalence of infection in 2021 in Bayinbuluke, Xinjiang, China. Sheep age was determined using incisor teeth. Cyst activity and calcification were determined using US images. The dogs were dewormed with praziquantel once a year to control echinococcosis in the community. RESULTS: Three flocks had 968 sheep in 2014, with 13.22%, 22.62%, 18.7%, 27.27%, 11.88%, and 6.3% of sheep aged 1, 2, 3, 4, 5, and ≥ 6 years old, respectively. US scanning revealed that the overall CE prevalence was 38.43% (372/968), with active cysts and calcified cysts present in 9.40% (91/968) and 29.02% (281/968) of the sheep, respectively. For the young sheep aged 1 and 2 years, the prevalence of active and calcified cysts was: 1.56% and 0.91%, and 10.94% and 18.72%, respectively. Approximately 15.15% and 16.52% of the 4- and 5-year-old sheep, respectively, harbored active cysts. There was no significant difference in the infection rates of sheep between 2014 and 2021 (P > 0.05). CONCLUSIONS: US is a practical tool for the field screening of CE in sheep flocks. One-third of the sheep population in the flocks was 1-2 years old, and these sheep played a very limited role in CE transmission, as most of the cysts were calcified. Old sheep, especially culled aged sheep, play a key role in the transmission of CE. Dosing dogs once a year did not affect echinococcosis control.
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Equinococosis Hepática , Enfermedades de las Ovejas , Ultrasonografía , Animales , Enfermedades de las Ovejas/epidemiología , Enfermedades de las Ovejas/parasitología , Enfermedades de las Ovejas/diagnóstico por imagen , Ovinos , China/epidemiología , Ultrasonografía/veterinaria , Equinococosis Hepática/veterinaria , Equinococosis Hepática/epidemiología , Equinococosis Hepática/diagnóstico por imagen , Prevalencia , Perros , Praziquantel/uso terapéutico , Antihelmínticos/uso terapéutico , FemeninoRESUMEN
We conducted this study to assess the effect of ultrasound osteotome on surgical site wound infection and pain following removal of mandibular wisdom teeth. A computerised search of Embase, Cochrane Library, PubMed, Wanfang and China National Knowledge Infrastructure databases for publicly available randomised controlled trials (RCTs) on the clinical effects of applying ultrasound osteotome to extract mandibular wisdom teeth was conducted from the inception of the databases to September 2023. Two researchers independently screened the retrieved results for literature screening, quality assessment and data extraction. RevMan 5.4 software was applied for data analysis. A total of 17 RCTs were included in this study, including 848 cases in the ultrasound osteotome group and 842 cases in the control group. The analysis revealed, compared with the control group, the ultrasound osteotome group showed a significantly lower incidence of postoperative wound infection (1.42% vs. 5.46%, odds ratio [OR]: 0.30, 95% confidence intervals [CI]: 0.17-0.53, p < 0.0001), fewer postoperative complications (6.35% vs. 22.12%, OR: 0.23, 95% CI: 0.17-0.32, p < 0.00001), shorter operative time (standardised mean differences [SMD]: -1.30, 95% CI: -1.97 to -0.64, p = 0.0001) and lower wound pain scores (SMD: -2.26 95% CI -2.80 to -1.73, p < 0.00001). Strong evidence suggests that ultrasound osteotome applied to extract mandibular wisdom teeth is more advantageous in terms of lower postoperative wound infection, less wound pain, fewer postoperative complications and shorter operative time compared with conventional treatment methods, but large-scale, multicentre RCTs are still needed to obtain more accurate results.
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Tercer Molar , Infección de la Herida Quirúrgica , Humanos , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/epidemiología , Tercer Molar/cirugía , Extracción Dental/efectos adversos , Extracción Dental/métodos , Técnicas de Cierre de Heridas , DolorRESUMEN
Precipitation can be used for the removal of impurities early in the downstream purification process of biologics, with the soluble product remaining in the filtrate through microfiltration. The objective of this study was to examine the use of polyallylamine (PAA) precipitation to increase the purity of product via higher host cell protein removal to enhance polysorbate excipient stability to enable a longer shelf life. Experiments were performed using three monoclonal antibodies (mAbs) with different properties of isoelectric point and IgG subclass. High throughput workflows were established to quickly screen precipitation conditions as a function of pH, conductivity and PAA concentrations. Process analytical tools (PATs) were used to evaluate the size distribution of particles and inform the optimal precipitation condition. Minimal pressure increase was observed during depth filtration of the precipitates. The precipitation was scaled up to 20L size and the extensive characterization of precipitated samples after protein A chromatography showed >75% reduction of host cell protein (HCP) concentrations (by ELISA), >90% reduction of number of HCP species (by mass spectrometry), and >99.8% reduction of DNA. The stability of polysorbate containing formulation buffers for all three mAbs in the protein A purified intermediates was improved at least 25% after PAA precipitation. Mass spectrometry was used to obtain additional understanding of the interaction between PAA and HCPs with different properties. Minimal impact on product quality and <5% yield loss after precipitation were observed while the residual PAA was <9 ppm. These results expand the toolbox in downstream purification to solve HCP clearance issues for programs with purification challenges, while also providing important insights into the integration of precipitation-depth filtration and the current platform process for the purification of biologics.
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Productos Biológicos , Polímeros , Cricetinae , Animales , Cricetulus , Polisorbatos , Anticuerpos Monoclonales/química , Células CHORESUMEN
Picturing the atomic migration pathways of catalysts in a reactive atmosphere is of central significance for uncovering the underlying catalytic mechanisms and directing the design of high-performance catalysts. Here, we describe a reduction-controlled atomic migration pathway that converts nanoparticles to single atom alloys (SAAs), which has remained synthetically challenging in prior attempts due to the elusive mechanism. We achieved this by thermally treating the noble-metal nanoparticles M (M = Ru, Rh, Pd, Ag, Ir, Pt, and Au) on metal oxide (CuO) supports with H2/Ar. Atomic-level characterization revealed such conversion as the synergistic consequence of noble metal-promoted H2 dissociation and concomitant CuO reduction. The observed atomic migration pathway offers an understanding of the dynamic mechanisms study of nanomaterials formation and catalyst design.
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Aleaciones , Nanopartículas del Metal , CatálisisRESUMEN
Sphingomyelinase (SMase) is closely related to diseases like Niemann-Pick disease and atherosclerosis, and the development of a simple method for the assay of SMase activity is very useful to screen new potential inhibitors or stimulators of SMase or biomarkers of disease. Fluorophore-encapsulated nanoliposomes (FENs) are emerging as a new fluorescent probe for sensing the enzymatic activity. In this work, two fluorochromes (cy7 and IR780) were encapsulated into the liposome of sphingomyelin, and therefore, a sphingomyelin-based ratiometric FEN probe for the SMase activity assay was constructed. The probe shows high selectivity and sensitivity to acid SMase with a detection limit of 4.8 × 10-4 U/mL. Sphingomyelin is the natural substrate of SMase; therefore, the probe has native ability for all kinds of SMase activity assays. Moreover, the probe has been successfully applied to the analysis of acid SMase activity in cells and urine samples. As far as we know, this is the first example of a nanoliposome fluorescence method for assaying acid SMase, and the method is biocompatible and much simpler than the existing ones, which might provide a new strategy for developing new methods for other important esterases.
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Colorantes Fluorescentes , Esfingomielina Fosfodiesterasa , Humanos , Liposomas , EsfingomielinasRESUMEN
We report a new scheme for chiral recognition using coordination polymers of Ag+ with a chiral thiol ligand that contains a binding group. N-Benzoyl-l-cysteine ethyl ester equipped with a boronic acid group at the para position of the phenyl ring forms coordination polymers with Ag+ in alkaline aqueous solutions that exhibit excellent selectivity toward a d-glucose enantiomer over l-glucose, while the coordination polymers from the d-cysteine-based thiol ligand are specific for l-glucose. It is assumed that a conformation change occurs upon interaction of a saccharide molecule with the polymeric chain receptor, for which the next binding is promoted, leading to the highly effective chiral recognition, despite the flexible nature of the polymeric receptor.
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Complejos de Coordinación/química , Cisteína/química , Glucosa/análisis , Polímeros/química , Plata/química , Compuestos de Sulfhidrilo/química , Sitios de Unión , Complejos de Coordinación/síntesis química , Ligandos , Estructura MolecularRESUMEN
Self-immolative polymers are a special kind of degradable polymers that depolymerize into small molecules through a cascade of reactions upon stimuli-triggered cleavage of the polymer chain ends. This work reports the design and synthesis of a fluoride-triggered self-immolative polyester. A 2,4-disubstitued 4-hydroxy butyrate is first confirmed to quickly cyclize in solution to form a γ-butyrolactone derivative. Then, the Passerini three component reaction (P-3CR) of an AB dimer (A: aldehyde, B: carboxylic acid) with tert-butyl isocyanide or oligo(ethylene glycol) isocyanide affords two poly(2,4-disubstitued 4-hydroxybutyrate) derivatives (P2 and P3). Two silyl ether end-capped polymers (P4 and P5) are abtained from P2 and P3, and their degradation in solution is examined by NMR spectrum and size exclusion chromatography. Polymers P4 and P5 are stable in the absence of tetrabutylammonium fluoride (TBAF), while in the presence of TBAF, the molar masses of P4 and P5 gradually decrease with time together with the increase of the amount of formed 2,4-disubstitued γ-butyrolactone. The depolymerization mechanism is proposed. The first step is the fast removal of the silyl ether by fluoride. Then, the released hydroxyl group initiates the quick head-to-tail depolymerization of the polyester via intramolecular cyclization.
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Fluoruros , Polímeros , Hidroxibutiratos , PoliésteresRESUMEN
Alginate-gelatin (Alg-Gel) composite hydrogel is extensively used in extrusion-based bioprinting. Although Alg-Gel blends possess excellent biocompatibility and printability, poor mechanical properties have hindered its further clinical applications. In this study, a series of design by incorporating bioactive glass nanoparticles (BG) (particle size of 12 and 25 nm) into Alg-Gel hydrogel have been considered for optimizing the mechanical and biological properties. The composite Alg-Gel-BG bioink was biophysically characterized by mechanical tests and bioprinting practice. Biocompatibility of Alg-Gel-BG bioink was then investigated by bioprinting mouse dermal fibroblasts. Mechanical tests showed enhanced stiffness with increasing concentration of incorporated BG. But the maximum concentration of BG was determined 1.0 wt% before blends became too viscous to print. Meanwhile, the incorporation of BG did not affect the highly porous structure and biodegradation of Alg-Gel hydrogel, while the mechanical strength and printability were enhanced. In addition, the cellular proliferation and adhesion in the bioprinted constructs were significantly enhanced by BG (12 nm), while extension was not affected. Therefore, our strategy of incorporating BG in Alg-Gel composite hydrogel represents an easy-to-use approach to the mechanical reinforcement of cell-laden bioink, thus demonstrating their suitability for future applications in extrusion-based bioprinting.
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Alginatos/química , Bioimpresión , Cerámica , Fibroblastos/metabolismo , Gelatina/química , Nanopartículas/química , Piel/metabolismo , Ingeniería de Tejidos/instrumentación , Animales , Materiales Biocompatibles/química , Biofisica , Adhesión Celular , Proliferación Celular , Hidrogeles , Ratones , Ratones Endogámicos C57BL , Porosidad , Impresión Tridimensional , Reología , Estrés Mecánico , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , ViscosidadRESUMEN
Pyrogenic carbonaceous matter (PCM) is redox-active and promotes both abiotic and biotic reactions in the environment, possibly as a result of its conductivity and phenolic/quinone functional groups. However, due to the complexity of PCM, the contribution of conductivity or phenolic/quinone functional groups to its redox activity is poorly understood, which hinders its potential engineering applications. Here, we synthesized tunable conjugated microporous polymers (CMPs) that possess key properties of PCM, which can be used as PCM analogues to provide insights to PCM reactivity. Specifically, controlled incorporation of phenolic moieties into CMPs during polymer synthesis affected electron-donating capacity, while carbonization of CMPs at various temperatures altered conductivity. Both properties were then correlated with PCM reactivity measured by the decay kinetics of a model pollutant trichloronitromethane. We demonstrate that some of the prepared CMPs enabled transformation of trichloronitromethane, while no decay was observed in the absence of CMPs. Results of further investigation suggest that trichloronitromethane decay occurs by reductive dechlorination, suggesting that CMPs are electron donors and the first dissociative electron transfer from CMPs was likely to be the rate-limiting step. Conductivity but not electron-donating capacity was positively correlated with CMP-mediated trichloronitromethane decay kinetics, suggesting an important role of the electron transfer kinetics at the interface for PCM-mediated transformation of environmental pollutants.
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Contaminantes Ambientales , Polímeros , Transporte de Electrón , Cinética , Oxidación-ReducciónRESUMEN
In this study, a molecularly imprinted polymer capable of recognizing 15 sulfonamides was first synthesized with sulfabenz as the dummy template. The calculation results from computation simulation showed that the specific 3D conformation of the template had an important influence on the polymer's recognition ability. Then, the polymer was used as recognition reagent to prepare a chemiluminescence sensor on a conventional 96-well microplate for the determination of the residues of 15 sulfonamides in meat (chicken and pork). Due to the 4-(imidazol-1-yl)phenol-enhanced luminol-H2O2 system, the limits of detection for the 15 analytes were in the range of 1.0-12 pg/mL. The recoveries from the standard fortified blank samples were in the range of 72.7-99%. Furthermore, one assay could be finished within 30 min, and the sensor could be reused 4 times. Therefore, this sensor could be used as a very useful tool for routine screening of residues of sulfonamides in meat samples. Graphical abstract Assay procedures of the molecularly imprinted polymer-based chemiluminescence sensor for determination of sulfonamides.
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Residuos de Medicamentos/análisis , Contaminación de Alimentos/análisis , Mediciones Luminiscentes/métodos , Impresión Molecular/métodos , Polímeros/química , Carne Roja/análisis , Sulfonamidas/análisis , Animales , Pollos , Simulación por Computador , Peróxido de Hidrógeno/química , Límite de Detección , Luminol/química , Microscopía Electrónica de Rastreo , Estándares de Referencia , Reproducibilidad de los Resultados , Sulfonamidas/normasRESUMEN
BACKGROUND AND AIM: Although several randomized controlled trials (RCTs) have reported that supplemental simethicone (SIM) can improve bowel preparation based on polyethylene glycol, there is no consensus as to whether SIM can ultimately increase the adenoma detection rate (ADR) during colonoscopy. A meta-analysis was performed to assess the effect of SIM on ADR during colonoscopy. METHODS: Databases including PubMed, EMBASE, and the Cochrane Library were searched to find relevant RCTs. RCTs evaluating the effect of pre-procedure SIM on the ADR during colonoscopy were finally included, and fixed effect models were applied. RESULTS: Six trials involving 1855 patients were finally included. The present meta-analysis suggested that the ADR during colonoscopy was significantly increased by supplemental SIM (27.9% vs 23.3%, P = 0.02), with a relative risk of 1.20 (95% confidence interval 1.03-1.39). Subgroup analysis suggested that supplemental SIM may be more useful to improve ADR during colonoscopy in endoscopic centers with low baseline ADR. CONCLUSIONS: Supplemental SIM for bowel preparation based on polyethylene glycol is useful to improve the ADR during colonoscopy.
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Adenoma/patología , Antiespumantes/administración & dosificación , Catárticos/administración & dosificación , Colonoscopía , Neoplasias Colorrectales/patología , Simeticona/administración & dosificación , Irrigación Terapéutica/métodos , Adulto , Antiespumantes/efectos adversos , Catárticos/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Ensayos Clínicos Controlados Aleatorios como Asunto , Simeticona/efectos adversos , Irrigación Terapéutica/efectos adversosRESUMEN
BACKGROUND AND AIMS: Good gastric preparation is essential for magnetically controlled capsule gastroscopy (MCCG) examination. This study aims to determine if repetitive position change after dimethicone premedication could further improve gastric cleanliness for MCCG. METHODS: Consecutive patients referred for MCCG in our center from May 7 to May 31, 2018 were prospectively enrolled and randomized to undergo repetitive position change for 15 min (position change group) or not (conventional group) after ingesting dimethicone. Primary outcome was gastric cleanliness score and secondary outcomes were detection rate of positive findings, number of lesions per patient, gastric examination time, and safety of MCCG. RESULTS: Totals of 43 and 40 were included in the position change and conventional groups, respectively. Gastric cleanliness score in the position change group was significantly higher than in the conventional group (21.2 ± 1.0 vs. 18.6 ± 2.0, P < 0.001), as was the proportion of acceptable gastric cleanliness (gastric cleanliness score ≥ 18) (100% vs. 72.5%, P < 0.001). There was no statistical difference in detection rate of positive findings between the two groups (27.9% vs. 27.5%, P = 0.97). In the position change group, the gastric examination time was significantly reduced (13.2 ± 4.0 vs. 15.3 ± 5.1, P = 0.043). No adverse events were observed. CONCLUSIONS: Repetitive position change after dimethicone premedication significantly improves gastric cleanliness for MCCG examination. Clinical Trial Registration ClinicalTrials.gov, ID: NCT03514966.
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Endoscopía Capsular/métodos , Ayuno/fisiología , Vaciamiento Gástrico/fisiología , Gastroscopía/métodos , Posicionamiento del Paciente/métodos , Neoplasias Gástricas/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Dimetilpolisiloxanos/administración & dosificación , Femenino , Vaciamiento Gástrico/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Método Simple Ciego , Adulto JovenRESUMEN
BACKGROUND AND STUDY AIMS: Ideal bowel preparation for colonoscopy requires complete removal of fluid and foam from the colon. Polyethylene glycol (PEG) is widely used for bowel preparation, with antifoaming agents such as simethicone commonly used in combination with PEG. Data on the effect of simethicone on the adenoma detection rate (ADR) were limited. This study therefore aimed to investigate whether preprocedure simethicone could increase the ADR. PATIENTS AND METHODS: This was a prospective, multicenter, endoscopist-blinded randomized controlled trial involving consecutive patients who underwent colonoscopy in six centers in China. Patients were randomly assigned to one of two groups: PEG plus simethicone or PEG alone. The primary outcome was ADR; secondary outcomes were quality of bowel preparation, measured by the Boston bowel preparation scale (BBPS) and bubble scores. RESULTS: 583 patients were included. More adenomas were detected in the PEG plus simethicone group than in the PEG alone group (ADR 21.0â% vs. 14.3â%, Pâ=â0.04; advanced ADR 9.0â% vs. 7.0â%, Pâ=â0.38). The mean number of adenomas detected was 2.20â±â1.36 vs. 1.63â±â0.89 (Pâ=â0.02). Patients in the PEG plus simethicone group showed better bowel cleansing efficacy: BBPSâ≥â6 in 88.3â% vs. 75.2â% (Pâ<â0.001) and bubble scores of 1.00â±â1.26 vs. 3.98â±â2.50 (Pâ<â0.001). Abdominal bloating was reported less frequently in the PEG plus simethicone group (7.8â% vs. 19.7â%, Pâ<â0.001) than in the PEG alone group. CONCLUSION: Combined use of PEG and simethicone is associated with a significantly increased ADR in a Chinese population.
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Adenoma/diagnóstico , Colon/diagnóstico por imagen , Neoplasias del Colon/diagnóstico , Colonoscopía/métodos , Simeticona/administración & dosificación , Administración Oral , Adolescente , Adulto , Anciano , Antiespumantes/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Adulto JovenRESUMEN
The authors describe a fluorometric method for the quantitation of nucleic acids by combining (a) cycled strand displacement amplification, (b) the unique features of the DNA probe SYBR Green, and (c) polydopamine nanotubes. SYBR Green undergoes strong fluorescence enhancement upon intercalation into double-stranded DNA (dsDNA). The polydopamine nanotubes selectively adsorb single-stranded DNA (ssDNA) and molecular beacons. In the absence of target DNA, the molecular beacon, primer and SYBR Green are adsorbed on the surface of polydopamine nanotubes. This results in quenching of the fluorescence of SYBR Green, typically measured at excitation/emission wavelengths of 488/518 nm. Upon addition of analyte (target DNA) and polymerase, the stem of the molecular beacon is opened so that it can bind to the primer. This triggers target strand displacement polymerization, during which dsDNA is synthesized. The hybridized target is then displaced due to the strand displacement activity of the polymerase. The displaced target hybridizes with another molecular beacon. This triggers the next round of polymerization. Consequently, a large amount of dsDNA is formed which is detected by addition of SYBR Green. Thus, sensitive and selective fluorometric detection is realized. The fluorescent sensing strategy shows very good analytical performances towards DNA detection, such as a wide linear range from 0.05 to 25 nM with a low limit of detection of 20 pM. Graphical abstract Schematic of a fluorometric strategy for highly sensitive and selective determination of nucleic acids by combining strand displacement amplification and the unique features of SYBR Green I (SG) and polydopamine nanotubes.
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Fluorometría/métodos , Ácidos Nucleicos/análisis , Benzotiazoles , Sondas de ADN/química , ADN de Cadena Simple , Diaminas , Fluorometría/normas , Indoles , Nanotubos/química , Técnicas de Amplificación de Ácido Nucleico/métodos , Compuestos Orgánicos , Polimerizacion , Polímeros , QuinolinasRESUMEN
BACKGROUND AND AIMS: Gum chewing can accelerate motility in the GI tract; clinical studies suggested gum chewing can reduce postoperative ileus. However, no trial has investigated the effect of gum chewing on bowel preparation for colonoscopy in addition to polyethylene glycol (PEG). The objective of this study was to investigate whether gum chewing before colonoscopy can increase the quality of bowel preparation. METHODS: This was a single-center, randomized controlled trial. Consecutive patients undergoing colonoscopy were randomized to the gum group or the control group. Patients in the gum group chewed sugar-free gum every 2 hours for 20 minutes each time from the end of drinking 2 L of PEG to the beginning of colonoscopy. Patients in the control group only received 2 L of PEG before colonoscopy. The quality of bowel preparation, procedure time, adenoma detection rate, patients' tolerance, and adverse events were compared. RESULTS: Three hundred patients were included in the study (150 in the control group, 150 in the gum group). More than 90% of patients in both groups were satisfied with the process of bowel preparation, and the incidence of adverse events was comparable in the 2 groups (41.3% vs 46.0%, P = .42). The mean Boston Bowel Preparation Scale score was 6.2 ± 1.4 and 6.1 ± 1.2 in the control group and the gum group, respectively, and the difference between the 2 groups was not significant (P = .51). CONCLUSIONS: This study indicates that gum chewing does not improve the quality of bowel preparation for colonoscopy, but it can improve patients' satisfaction with the process of bowel preparation and does not have negative effects on cleanliness. (Clinical trials registration number: NCT02507037.).
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Adenoma/diagnóstico por imagen , Goma de Mascar , Colonoscopía , Neoplasias Colorrectales/diagnóstico por imagen , Adulto , Catárticos/administración & dosificación , Catárticos/efectos adversos , Goma de Mascar/efectos adversos , Colonoscopía/efectos adversos , Colonoscopía/normas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Satisfacción del Paciente , Polietilenglicoles/administración & dosificación , Polietilenglicoles/efectos adversos , Método Simple CiegoRESUMEN
OBJECTIVES: In this study, an improved lyophilized PEGylated liposomal formulation of docetaxel (DOC) has been developed. METHODS: PEGylated docetaxel liposome (PL-DOC) was prepared by thin-film evaporation method and lyophilization. The effect of various components of the lipids and their compatibility with DOC on the entrapment efficiency (EE) of liposome was investigated. The lyophilized PL-DOC was characterized by morphology, particle size, zeta potential, EE, release in vitro and stability. Pharmacokinetics and biodistribution in vivo of lyophilized PL-DOC were also investigated. RESULTS: The optimal liposome formulation was egg phosphatidylcholine (EPC):cholesterol (CH):DSPE-PEG2000:DOC = 56:40:4:4 (molar ratio). Sucrose and mannitol were chosen as cryoprotectant in the lyophilization (cryoprotectant-to-lipid (C/L) mass ratio = 8:1). The size of lyophilized PL-DOC was 152.3 ± 1.0 nm with negative charge and the EE was 89.75 ± 1.79%. Compared with nonlyophilized PL-DOC, the lyophilized PL-DOC was more stable at 4 °C for six months. The lyophilized PL-DOC also showed the good stability after reconstituted by 5% glucose injection. In vitro release study of PL-DOC showed that PL-DOC had a sustained release effect. After i.v. administration at the dose of 10 mg/kg in rats, a significant increase in the AUC0-∞, MRT0-∞ and t1/2 was observed in PL-DOC group compared with conventional docetaxel liposome (CL-DOC) and DOC injection (DOC-I) group. Biodistribution studies in mice showed that PL-DOC significantly decreased the uptake by the organs of mononuclear phagocytic system (MPS), such as liver and spleen, while prolonging the retention time of DOC in the plasma. CONCLUSION: Our PEGylated liposome formulation reported in this study could potentially produce viable clinical strategies for improved delivery of DOC for the treatment of human cancer.
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Taxoides/farmacocinética , Animales , Docetaxel , Liposomas/análisis , Liposomas/farmacocinética , Ratones , Ratones Endogámicos , Ratas , Ratas Sprague-Dawley , Taxoides/análisis , Distribución TisularRESUMEN
A new kind of recyclable and reusable PEG-supported Jørgensen-Hayashi catalyst is synthesized for the first time and proven to be efficient for the enamine-catalyzed asymmetric Michael reaction with generally moderate to good diastereoselectivity and high to excellent enantioselectivity (up to 6 : 1 dr, 99% ee). The prepared PEG-supported catalyst can be recovered eight times and was found to provide similar diastereoselectivity and enantioselectivity to unsupported functional catalysts.