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1.
AJR Am J Roentgenol ; 220(6): 873-883, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36475816

RESUMEN

BACKGROUND. Consensus is lacking regarding optimal embolic agents for transcatheter arterial embolization (TAE) of renal angiomyolipomas (AMLs). OBJECTIVE. The purpose of our study was to compare the safety and efficacy of TAE with polyvinyl alcohol (PVA) and TAE with a combination of ethiodized oil (Lipiodol)-bleomycin emulsion and N-butyl cyanoacrylate (NBCA)-Lipiodol emulsion for the treatment of patients with large or symptomatic AMLs. METHODS. This prospective study enrolled patients referred for TAE of a large (> 4 cm) or symptomatic renal AML from July 2007 to December 2018. Patients were randomized to undergo TAE using PVA particles or a combination of Lipiodol-bleomycin emulsion and NBCA-Lipiodol emulsion. Patients underwent serial clinical follow-up visits and follow-up CT or MRI examinations after TAE. Outcomes were compared between groups. RESULTS. Seventy-eight patients were enrolled. After exclusions, the analysis included 72 patients (15 men, 57 women; mean age, 35.0 years; 51 patients with hematuria, 66 patients with flank pain): 35 patients were randomized to treatment by PVA and 37 were randomized to treatment by a combination of Lipiodol-bleomycin emulsion and NBCA-Lipiodol emulsion. Complete occlusion of all angiographically visible arterial supply was achieved in all patients. No major adverse event occurred in any patient. The mean follow-up after TAE was 77 ± 45 (SD) months (range, 37-180 months). The frequency of resolution of hematuria after initial TAE without recurrence was greater after treatment by Lipiodol-bleomycin emulsion and NBCA-Lipiodol emulsion than by PVA (100.0% vs 80.0%, respectively; p = .03). At 12-month follow-up, the frequency of complete resolution of flank pain was higher after treatment by Lipiodol-bleomycin emulsion and NBCA-Lipiodol emulsion than by PVA (100.0% vs 75.0%, p = .03). Mean reduction in AML volume at 36 months or longer after TAE versus at baseline was greater in patients treated by Lipiodol-bleomycin emulsion and NBCA-Lipiodol emulsion than in those treated by PVA (98.0% vs 85.7%, respectively; p = .04). The frequency of complete response by modified RECIST (mRECIST) criteria at 36 months or longer after TAE was greater in patients treated by Lipiodol-bleomycin emulsion and NBCA-Lipiodol emulsion than by PVA (94.6% vs 74.3%, p = .04). The rate of repeat TAE was higher among patients treated by PVA than among those treated by Lipiodol-bleomycin emulsion and NBCA-Lipiodol emulsion (25.7% vs 8.1%, p = .04). CONCLUSION. Superior outcomes after TAE of AML were achieved using Lipiodol-bleomycin emulsion and NBCA-Lipiodol emulsion than using PVA. CLINICAL IMPACT. TAE using a combination of Lipiodol-bleomycin emulsion and NBCA-Lipiodol emulsion is a safe and effective treatment option for large or symptomatic AMLs. TRIAL REGISTRATION. Chinese Clinical Trial Registry ChiCTR2100053296.


Asunto(s)
Angiomiolipoma , Embolización Terapéutica , Enbucrilato , Neoplasias Renales , Leucemia Mieloide Aguda , Masculino , Humanos , Femenino , Adulto , Aceite Etiodizado/uso terapéutico , Bleomicina , Estudios Prospectivos , Alcohol Polivinílico/uso terapéutico , Angiomiolipoma/diagnóstico por imagen , Angiomiolipoma/terapia , Emulsiones , Enbucrilato/uso terapéutico , Dolor en el Flanco , Hematuria , Neoplasias Renales/terapia , Neoplasias Renales/tratamiento farmacológico , Embolización Terapéutica/métodos , Resultado del Tratamiento , Leucemia Mieloide Aguda/tratamiento farmacológico
2.
Zhongguo Zhong Yao Za Zhi ; 48(13): 3472-3484, 2023 Jul.
Artículo en Zh | MEDLINE | ID: mdl-37474984

RESUMEN

Ginsenoside Rg_3, an active component of traditional Chinese medicine(TCM), was used as the substitute for cholesterol as the membrane material to prepare the ginsenoside Rg_3-based liposomes loaded with dihydroartemisinin and paclitaxel. The effect of the prepared drug-loading liposomes on triple-negative breast cancer in vitro was evaluated. Liposomes were prepared with the thin film hydration method, and the preparation process was optimized by single factor experiments. The physicochemical properties(e.g., particle size, Zeta potential, and stability) of the liposomes were characterized. The release behaviors of drugs in different media(pH 5.0 and pH 7.4) were evaluated. The antitumor activities of the liposomes were determined by CCK-8 on MDA-MB-231 and 4T1 cells. The cell scratch test was carried out to evaluate the effect of the liposomes on the migration of MDA-MB-231 and 4T1 cells. Further, the targeting ability of liposomes and the mechanism of lysosome escape were investigated. Finally, H9c2 cells were used to evaluate the potential cardiotoxicity of the preparation. The liposomes prepared were spheroid, with uniform particle size distribution, the ave-rage particle size of(107.81±0.01) nm, and the Zeta potential of(2.78±0.66) mV. The encapsulation efficiency of dihydroartemisinin and paclitaxel was 57.76%±1.38% and 99.66%±0.07%, respectively, and the total drug loading was 4.46%±0.71%. The accumulated release of dihydroartemisinin and paclitaxel from the liposomes at pH 5.0 was better than that at pH 7.4, and the liposomes could be stored at low temperature for seven days with good stability. Twenty-four hours after administration, the inhibition rates of the ginsenoside Rg_3-based liposomes loaded with dihydroartemisinin(70 µmol·L~(-1)) and paclitaxel on MDA-MB-231 and 4T1 cells were higher than those of the positive control(adriamycin) and free drugs(P<0.01). Compared with free drugs, liposomes inhibited the migration of MDA-MB-231 and 4T1 cells(P<0.05). Liposomes demonstrated active targeting and lysosome escape. In particular, liposomes showed lower toxicity to H9c2 cells than free drugs(P<0.05), which indicated that the preparation had the potential to reduce cardiotoxicity. The findings prove that ginsenoside Rg_3 characterized by the combination of drug and excipient is an ideal substitute for lipids in liposomes and promoted the development of innovative TCM drugs for treating cancer.


Asunto(s)
Ginsenósidos , Neoplasias de la Mama Triple Negativas , Humanos , Paclitaxel/farmacología , Liposomas/química , Ginsenósidos/farmacología , Ginsenósidos/uso terapéutico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Cardiotoxicidad/tratamiento farmacológico , Línea Celular Tumoral
3.
Mol Phylogenet Evol ; 139: 106542, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31229601

RESUMEN

Goodyerinae are one of the most species-rich and widespread subtribes of Orchidaceae but notorious for their taxonomic difficulty. Here, a comprehensive molecular phylogenetic study of the subtribe is presented based on two nuclear (ITS, Xdh) and five plastid (matK, psaB, rbcL, trnL, trnL-F) regions. A total of 119 species were included representing all clades recovered by previous phylogenetic analyses as well as seven outgroups. Maximum parsimony, maximum likelihood and Bayesian inference methods were used to infer the phylogenetic relationships. The results show that the Goodyerinae subdivided into three major subdivisions and six groupings: Pachyplectron, Goodyera clade (including Goodyera procera, Microchilus subclade and Goodyera subclade) and Cheirostylis clade (including Gonatostylis, Cheirostylis subclade and Ludisia subclade). Four genera, Erythrodes, Goodyera, Myrmechis and Odontochilus, are not monophyletic. The results support Odontochilus s. l. to include Myrmechis and Kuhlhasseltia. The systematic positions of Goodyera procera and two isolated genera, Herpysma and Orchipedum, are difficult to determine.


Asunto(s)
Orchidaceae/clasificación , Teorema de Bayes , Núcleo Celular/genética , Orchidaceae/genética , Filogenia , Plastidios/genética
4.
Analyst ; 144(20): 6055-6063, 2019 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-31517337

RESUMEN

Unlike other extracellular vesicle (EV) subtypes such as exosomes, the lack of well-defined universal markers on the surface of microvesicles (MVs) has led to difficulty in the detection of the entire MV population. To design a universal MV detection method, we reported highly sensitive electrical detection of MVs using a reduced graphene oxide (RGO)-based field-effect transistor (FET) biosensor by the introduction of a membrane biotinylation strategy in this work. Biotinylated MVs (B-MVs) were obtained by supplying the culture medium with 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[biotinyl(polyethylene glycol)-2000] (DSPE-PEG-biotin) while cultivating the cells. Excellent biotinylation efficiency of MVs (92.6%) was then realized. A streptavidin (SA) probe was subsequently modified onto the channel surface of the as-fabricated RGO-based FET device, which was capable of specifically recognizing B-MVs due to the high affinity between SA and biotin in a 1 : 4 recognition format. The results showed that the RGO-based FET biosensor could detect B-MVs in a wide range from 105 particles per mL to 109 particles per mL with a low detection limit down to 20 particles per µL, which was the lowest value compared with other previously reported results. This platform also allowed distinguishing B-MVs from other unbiotinylated EV types such as MVs and exosomes, exhibiting excellent specificity. Moreover, this FET biosensor demonstrated the capability of detecting B-MVs derived from different cell lines including cancer cells and normal cells, indicating its versatility and potential applications in the biomedical field.


Asunto(s)
Técnicas Biosensibles/métodos , Biotina/metabolismo , Micropartículas Derivadas de Células/metabolismo , Exosomas/metabolismo , Grafito/química , Neoplasias Hepáticas/metabolismo , Hígado/metabolismo , Biotinilación , Células Endoteliales de la Vena Umbilical Humana , Humanos , Fosfatidiletanolaminas/química , Polietilenglicoles/química , Estreptavidina/metabolismo , Transistores Electrónicos
5.
Chem Biodivers ; 16(4): e1800646, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30706997

RESUMEN

A new series of (sulfonamido)propanamides (6a1-6a13, 6b1-6b15, 7c1-7c5, 6d1-6d5, 6e1-6e6) was designed and synthesized. All the synthesized compounds were characterized by NMR and mass spectrometry. The target compounds were evaluated for their in vitro cytotoxic activity against hepatocellular carcinoma (HepG2), fibrosarcoma (HT-1080), mouth epidermal carcinoma (KB), and breast adenocarcinoma (MCF-7) cell lines with the sulforhodamine B (SRB) assay, with gemcitabine and mitomycin C as positive controls. Most of these compounds exhibit a more potent cytotoxic effect than the positive control group on various cancer cell lines and the most potent compound, 6a7, shows the IC50 values of 29.78±0.516 µm, 30.70±0.61 µm, and 64.89±3.09 µm in HepG2, HT-1080, KB, and MCF-7 cell lines, respectively. Thus, these compounds with potent cytotoxic activity have potential for development as new chemotherapy agents.


Asunto(s)
Antineoplásicos/farmacología , Diseño de Fármacos , Propionatos/farmacología , Sulfonamidas/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Propionatos/síntesis química , Propionatos/química , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/química
6.
J Vasc Interv Radiol ; 29(12): 1694-1702, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30297313

RESUMEN

PURPOSE: To evaluate the safety and efficacy of prostatic artery embolization (PAE) using the combination of 50-µm and 100-µm polyvinyl alcohol (PVA) particles versus 100-µm PVA particles alone in the treatment of patients with symptomatic benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: Over a 5-year period, 120 patients treated with PAE for lower urinary tract symptoms (LUTS) secondary to BPH were randomized to undergo embolization with 50-µm plus 100-µm PVA particles (group A) or 100-µm PVA particles alone (group B). Mean follow-up time was 34 months (range, 12-57 mo). There were no differences between groups regarding baseline data. Primary outcome measurements included change in International Prostate Symptom Score (IPSS) and incidence of adverse events. Secondary outcome measurements included procedure-associated pain, prostate ischemia measured on magnetic resonance (MR) imaging 1 week after PAE, and changes over time in quality of life (QOL) questionnaire, peak urinary flow rate (Qmax), postvoid residual (PVR) volume, prostate volume (PV), prostate-specific antigen (PSA) level, and International Index of Erectile Function (IIEF) were evaluated. Recurrence of LUTS following PAE was defined as relief of LUTS temporally but increased IPSS ≥ 8 or QOL score ≥ 3 or decrease in Qmax to < 7 mL/s. RESULTS: Mean follow-up periods were 35 months ± 22 in group A and 33 months ± 25 in group B (P = .629). No differences between groups regarding procedural details, pain scores, or adverse events were noted (P > .05). At 24 month of follow-up, patients in group A had a greater decrease in mean IPSS (18.7 ± 12.5 vs 14.8 ± 13.5), QOL score (3.7 ± 1.5 vs 2.4 ± 1.8), Qmax (10.5 mL ± 9.5 vs 6.8 mL ± 5.0), PVR (92.0 mL ± 75.0 vs 60.0 mL ± 55.0), and PV (37.0 mL ± 19.5 vs 25.5 mL ± 15.0) compared with patients in group B (P < .05 for all). Mean ratios of prostate ischemic volume at 1 week after PAE were 70% ± 20 in group A and 41% ± 25 in group B (P = .021); mean PSA levels at 24 hour after PAE were 92.5 ng/mL ± 55.0 in group A and 77.5 ng/mL ± 45.0 in group B (P = .031); LUTS recurrence rates were 3.6% in group A and 14.6% in group B (P = .024). The mean IIEF-5 was not significantly different from baseline in either group. CONCLUSIONS: PAE with 50-µm plus 100-µm PVA particles resulted in greater improvement in clinical and imaging outcomes and no significant differences in adverse events compared with 100-µm PVA particles alone.


Asunto(s)
Embolización Terapéutica/métodos , Síntomas del Sistema Urinario Inferior/terapia , Alcohol Polivinílico/administración & dosificación , Próstata/irrigación sanguínea , Hiperplasia Prostática/terapia , Anciano , Anciano de 80 o más Años , Beijing , Método Doble Ciego , Embolización Terapéutica/efectos adversos , Humanos , Síntomas del Sistema Urinario Inferior/diagnóstico , Síntomas del Sistema Urinario Inferior/etiología , Síntomas del Sistema Urinario Inferior/fisiopatología , Imagen por Resonancia Magnética , Masculino , Microesferas , Persona de Mediana Edad , Alcohol Polivinílico/efectos adversos , Estudios Prospectivos , Hiperplasia Prostática/complicaciones , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/fisiopatología , Calidad de Vida , Recuperación de la Función , Factores de Tiempo , Resultado del Tratamiento
7.
Pediatr Blood Cancer ; 65(9): e27223, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29797637

RESUMEN

BACKGROUND: The aim of the study was to present long-term results of mandibular growth in pediatric parotid gland carcinoma survivors treated with interstitial brachytherapy. PROCEDURE: Twenty-five survivors of pediatric parotid gland carcinoma treated with iodine-125 seed interstitial brachytherapy were included for quantitative analysis, including three dimensional (3D) cephalometry and measurement of mandibular volume. RESULTS: 3D cephalometry showed that the median fore-and-aft increments of the lengths of the condyle, the ramus, and the body of the mandible were 1.23, 0.19, and 1.66 mm for the affected side, respectively, and were 1.37, 1.95, and 3.42 mm for the unaffected side, respectively. The difference in increments of the ramus was statistically significant between the affected side and the unaffected side (P = 0.003; P < 0.05). Moreover, mandibular volume measurements showed that the median fore-and-aft increments of the volumes of the condyle, the ramus, and the body of the mandible were 290.62, 220.14, and 1706.40 mm3 for the affected side, respectively, and were 269.15, 370.40, and 1469.86 mm3 for the unaffected side, respectively. The difference in increments was statistically significant between the affected side and the unaffected side for the ramus (P = 0.005; P < 0.05) and the body (P = 0.043; P < .05). CONCLUSION: Mandibular growth was affected by interstitial brachytherapy, especially for the ramus, in pediatric parotid gland carcinoma survivors treated with interstitial brachytherapy. Nevertheless, the impact was mild in these survivors.


Asunto(s)
Braquiterapia/efectos adversos , Carcinoma/radioterapia , Radioisótopos de Yodo/uso terapéutico , Mandíbula/efectos de la radiación , Neoplasias de la Parótida/radioterapia , Traumatismos por Radiación/etiología , Adolescente , Cefalometría , Niño , Femenino , Humanos , Imagenología Tridimensional , Masculino , Mandíbula/crecimiento & desarrollo , Tamaño de los Órganos , Traumatismos por Radiación/fisiopatología , Radioterapia Adyuvante/efectos adversos , Sobrevivientes
8.
Arch Virol ; 163(5): 1253-1262, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29399747

RESUMEN

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease. The outcomes of both spontaneous HCV clearance and response to therapy depend on both viral and host factors. To investigate the influence of polymorphisms of IL-28B rs12979860 and TBX21 rs17250932, rs4794067 as well as viral factors (HCV genotype, F protein) on the outcome of HCV infection, we genotyped 565 patients with chronic HCV infection, 191 patients spontaneously resolved from HCV infection, 359 healthy controls and 383 treatment-naïve CHC patients with pegylated interferon-α and ribavirin (PEG IFN-α/RBV). Results showed that TBX21 rs4794067 variant genotypes significantly correlated with increased risk of HCV chronic infection (dominant model: OR = 5.690, 95% CI = 2.024-16.000) and susceptibility (dominant model: OR = 5.658, 95% CI = 2.514-12.735). We also found that the rs12979860, rs2227982 and rs36084323 polymorphisms showed no significant associations with susceptibility or spontaneous clearance of HCV in the anti-F antibody subgroup; however, the anti-F antibody positive subgroup might show an increased risk of N-SVR (all P < 0.001). Our results demonstrate that variant factors in both the host and pathogen are commonly important for HCV clearance. In addition rs4794067 and F protein status may be strong predictive markers in the Chinese population.


Asunto(s)
Hepatitis C Crónica/genética , Hepatitis C Crónica/virología , Interleucinas/genética , Polimorfismo de Nucleótido Simple , Proteínas de Dominio T Box/genética , Adolescente , Adulto , Anciano , Anticuerpos Antivirales/sangre , Antivirales/uso terapéutico , Pueblo Asiatico/genética , China , Susceptibilidad a Enfermedades , Quimioterapia Combinada , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Hepacivirus/genética , Hepacivirus/inmunología , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/etnología , Humanos , Interferón-alfa/uso terapéutico , Interferones , Masculino , Persona de Mediana Edad , Polietilenglicoles/uso terapéutico , Ribavirina/uso terapéutico , Respuesta Virológica Sostenida , Proteínas del Núcleo Viral/inmunología , Adulto Joven
9.
Drug Dev Ind Pharm ; 44(2): 329-337, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29113503

RESUMEN

The objective of this study was to investigate the effect of crystalline state and a formulation of self-nanoemulsifying drug delivery system (SNEDDS) on oral bioavailability of 6-benzyl-1-benzyloxymethyl-5-iodouracil (W-1), a novel non-nucleoside reverse transcriptase inhibitor, in rats. The crystalline states of W-1 were characterized by scanning electron microscope (SEM), differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD). The SNEDDS was formulated by medium-chain lipids, characterized by droplet particle size. The plasma concentrations of W-1 were measured by high performance liquid chromatography (HPLC). The results indicated that W-1 compound were presented as crystalline forms, A and B, the degree of crystallization in form B was higher than that in form A. The SNEDDS of W-1 displayed a significant increase in the dissolution rate than W-1 powder. Furthermore, after oral administration of W-1 (100 mg/kg), the pharmacokinetic parameters of form A, form B, and W-1 SNEDDS were as follows: AUC0-t 526.4 ± 123.5, 305.1 ± 58.5 and 2297 ± 451 ng h/mL (p < .05, when W-1 SNEDDS were compared with either form A or form B), respectively. With SNEDDS formulation, the relative bioavailabilities were enhanced by 4.36-fold and 7.53-fold over the form A and form B of W-1, respectively. In conclusion, the present results suggested that the crystalline states of W-1 might lead to the lower oral bioavailability, and SNEDDS formulation is a promising strategy of improving bioavailability, in spite of that crystalline states usually carry small lot-to-lot variability.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/farmacocinética , Emulsiones/química , Nanopartículas/química , Uracilo/análogos & derivados , Administración Oral , Animales , Fármacos Anti-VIH/química , Área Bajo la Curva , Rastreo Diferencial de Calorimetría , Química Farmacéutica , Cristalización , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Semivida , Lípidos/química , Masculino , Tasa de Depuración Metabólica , Tamaño de la Partícula , Polietilenglicoles/química , Ratas , Ratas Sprague-Dawley , Tensoactivos/química , Uracilo/administración & dosificación , Uracilo/química , Uracilo/farmacocinética , Difracción de Rayos X
10.
Metab Eng ; 40: 176-185, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28216106

RESUMEN

Many desired phenotypes for producing cellulosic biofuels are often observed in industrial Saccharomyces cerevisiae strains. However, many industrial yeast strains are polyploid and have low spore viability, making it difficult to use these strains for metabolic engineering applications. We selected the polyploid industrial strain S. cerevisiae ATCC 4124 exhibiting rapid glucose fermentation capability, high ethanol productivity, strong heat and inhibitor tolerance in order to construct an optimal yeast strain for producing cellulosic ethanol. Here, we focused on developing a general approach and high-throughput screening method to isolate stable haploid segregants derived from a polyploid parent, such as triploid ATCC 4124 with a poor spore viability. Specifically, we deleted the HO genes, performed random sporulation, and screened the resulting segregants based on growth rate, mating type, and ploidy. Only one stable haploid derivative (4124-S60) was isolated, while 14 other segregants with a stable mating type were aneuploid. The 4124-S60 strain inherited only a subset of desirable traits present in the parent strain, same as other aneuploids, suggesting that glucose fermentation and specific ethanol productivity are likely to be genetically complex traits and/or they might depend on ploidy. Nonetheless, the 4124-60 strain did inherit the ability to tolerate fermentation inhibitors. When additional genetic perturbations known to improve xylose fermentation were introduced into the 4124-60 strain, the resulting engineered strain (IIK1) was able to ferment a Miscanthus hydrolysate better than a previously engineered laboratory strain (SR8), built by making the same genetic changes. However, the IIK1 strain showed higher glycerol and xylitol yields than the SR8 strain. In order to decrease glycerol and xylitol production, an NADH-dependent acetate reduction pathway was introduced into the IIK1 strain. By consuming 2.4g/L of acetate, the resulting strain (IIK1A) exhibited a 14% higher ethanol yield and 46% lower byproduct yield than the IIK1 strain from anaerobic fermentation of the Miscanthus hydrolysate. Our results demonstrate that industrial yeast strains can be engineered via haploid isolation. The isolated haploid strain (4124-S60) can be used for metabolic engineering to produce fuels and chemicals.


Asunto(s)
Celulosa/metabolismo , Etanol/metabolismo , Mejoramiento Genético/métodos , Ingeniería Metabólica/métodos , Saccharomyces cerevisiae/clasificación , Saccharomyces cerevisiae/fisiología , Acetatos/metabolismo , Vías Biosintéticas/genética , Etanol/aislamiento & purificación , Haploidia , Redes y Vías Metabólicas/genética , Especificidad de la Especie
11.
Acta Pharmacol Sin ; 38(5): 623-637, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28392569

RESUMEN

The adult mammalian CNS has a limited capacity to regenerate after traumatic injury. In this study, a combinatorial strategy to promote axonal regeneration and functional recovery after spinal cord injury (SCI) was evaluated in adult rats. The rats were subjected to a complete transection in the thoracic spinal cord, and multichannel scaffolds seeded with activated Schwann cells (ASCs) and/or rat bone marrow-derived mesenchymal stem cells (MSCs) were acutely grafted into the 3-mm-wide transection gap. At 4 weeks post-transplantation and thereafter, the rats receiving scaffolds seeded with ASCs and MSCs exhibited significant recovery of nerve function as shown by the Basso, Beattie and Bresnahan (BBB) score and electrophysiological test results. Immunohistochemical analyses at 4 and 8 weeks after transplantation revealed that the implanted MSCs at the lesion/graft site survived and differentiated into neuron-like cells and co-localized with host neurons. Robust bundles of regenerated fibers were identified in the lesion/graft site in the ASC and MSC co-transplantation rats, and neurofilament 200 (NF) staining confirmed that these fibers were axons. Furthermore, myelin basic protein (MBP)-positive myelin sheaths were also identified at the lesion/graft site and confirmed via electron microscopy. In addition to expressing mature neuronal markers, sparse MSC-derived neuron-like cells expressed choline acetyltransferase (ChAT) at the injury site of the ASC and MSC co-transplantation rats. These findings suggest that co-transplantation of ASCs and MSCs in a multichannel polymer scaffold may represent a novel combinatorial strategy for the treatment of spinal cord injury.


Asunto(s)
Axones/fisiología , Trasplante de Células Madre Mesenquimatosas , Células de Schwann/trasplante , Traumatismos de la Médula Espinal/terapia , Animales , Diferenciación Celular , Femenino , Ácido Láctico , Regeneración Nerviosa , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas Sprague-Dawley , Remielinización , Ingeniería de Tejidos
12.
J Ind Microbiol Biotechnol ; 44(3): 387-395, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28070721

RESUMEN

Accumulation of reduced byproducts such as glycerol and xylitol during xylose fermentation by engineered Saccharomyces cerevisiae hampers the economic production of biofuels and chemicals from cellulosic hydrolysates. In particular, engineered S. cerevisiae expressing NADPH-linked xylose reductase (XR) and NAD+-linked xylitol dehydrogenase (XDH) produces substantial amounts of the reduced byproducts under anaerobic conditions due to the cofactor difference of XR and XDH. While the additional expression of a water-forming NADH oxidase (NoxE) from Lactococcus lactis in engineered S. cerevisiae with the XR/XDH pathway led to reduced glycerol and xylitol production and increased ethanol yields from xylose, volumetric ethanol productivities by the engineered yeast decreased because of growth defects from the overexpression of noxE. In this study, we introduced noxE into an engineered yeast strain (SR8) exhibiting near-optimal xylose fermentation capacity. To overcome the growth defect caused by the overexpression of noxE, we used a high cell density inoculum for xylose fermentation by the SR8 expressing noxE. The resulting strain, SR8N, not only showed a higher ethanol yield and lower byproduct yields, but also exhibited a high ethanol productivity during xylose fermentation. As noxE overexpression elicits a negligible growth defect on glucose conditions, the beneficial effects of noxE overexpression were substantial when a mixture of glucose and xylose was used. Consumption of glucose led to rapid cell growth and therefore enhanced the subsequent xylose fermentation. As a result, the SR8N strain produced more ethanol and fewer byproducts from a mixture of glucose and xylose than the parental SR8 strain without noxE overexpression. Our results suggest that the growth defects from noxE overexpression can be overcome in the case of fermenting lignocellulose-derived sugars such as glucose and xylose.


Asunto(s)
Fermentación , Complejos Multienzimáticos/genética , NADH NADPH Oxidorreductasas/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Xilosa/metabolismo , Aldehído Reductasa/genética , Aldehído Reductasa/metabolismo , Biocombustibles/microbiología , D-Xilulosa Reductasa/genética , D-Xilulosa Reductasa/metabolismo , Etanol/metabolismo , Glucosa/metabolismo , Glicerol/metabolismo , Microbiología Industrial , Lignina/metabolismo , Microorganismos Modificados Genéticamente , Complejos Multienzimáticos/metabolismo , NADH NADPH Oxidorreductasas/metabolismo , Plásmidos/genética , Plásmidos/metabolismo , Ingeniería de Proteínas , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Xilitol/metabolismo
13.
Biotechnol Bioeng ; 113(12): 2587-2596, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27240865

RESUMEN

Xylose fermentation by engineered Saccharomyces cerevisiae expressing NADPH-linked xylose reductase (XR) and NAD+ -linked xylitol dehydrogenase (XDH) suffers from redox imbalance due to cofactor difference between XR and XDH, especially under anaerobic conditions. We have demonstrated that coupling of an NADH-dependent acetate reduction pathway with surplus NADH producing xylose metabolism enabled not only efficient xylose fermentation, but also in situ detoxification of acetate in cellulosic hydrolysate through simultaneous co-utilization of xylose and acetate. In this study, we report the highest ethanol yield from xylose (0.463 g ethanol/g xylose) by engineered yeast with XR and XDH through optimization of the acetate reduction pathway. Specifically, we constructed engineered yeast strains exhibiting various levels of the acetylating acetaldehyde dehydrogenase (AADH) and acetyl-CoA synthetase (ACS) activities. Engineered strains exhibiting higher activities of AADH and ACS consumed more acetate and produced more ethanol from a mixture of 20 g/L of glucose, 80 g/L of xylose, and 8 g/L of acetate. In addition, we performed environmental and genetic perturbations to further improve the acetate consumption. Glucose-pulse feeding to continuously provide ATPs under anaerobic conditions did not affect acetate consumption. Promoter truncation of GPD1 and gene deletion of GPD2 coding for glycerol-3-phosphate dehydrogenase to produce surplus NADH also did not lead to improved acetate consumption. When a cellulosic hydrolysate was used, the optimized yeast strain (SR8A6S3) produced 18.4% more ethanol and 41.3% less glycerol and xylitol with consumption of 4.1 g/L of acetate than a control strain without the acetate reduction pathway. These results suggest that the major limiting factor for enhanced acetate reduction during the xylose fermentation might be the low activities of AADH and ACS, and that the redox imbalance problem of XR/XDH pathway can be exploited for in situ detoxification of acetic acid in cellulosic hydrolysate and increasing ethanol productivity and yield. Biotechnol. Bioeng. 2016;113: 2587-2596. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Acetatos/metabolismo , Aldehído Oxidorreductasas/metabolismo , Celulosa/metabolismo , Coenzima A Ligasas/metabolismo , Etanol/metabolismo , Saccharomyces cerevisiae/fisiología , Aldehído Oxidorreductasas/genética , Coenzima A Ligasas/genética , Etanol/aislamiento & purificación , Mejoramiento Genético/métodos , Ingeniería Metabólica/métodos , Oxidación-Reducción , Transducción de Señal/fisiología
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(1): 64-9, 2016 Jan.
Artículo en Zh | MEDLINE | ID: mdl-27228742

RESUMEN

Biomass energy is being industrialized rapidly in China in recent years, whereas, research on energy grass is still in primary stage. Only if near-infrared spectroscopy mode was constructed which was used to predict the lignin, cellulose and hemicellulose contents in energy crop, the varieties screening, performance evaluation and on-line control of industrialization would be facilitated. In this study, the prediction model for quality indices (cellulose, hemicellulose, lignin and ash) of four energy grass (Miscanthus) was built using Fourier transform near-infrared (FT-NIR) spectroscopy combined with partial least squares regression (PLSR), and the impacts exerted by particle size on the model were also revealed. The results showed that (1) the root mean error of cross validation (RMSECV) of cellulose, hemicelluloses and lignin contents were 1.35% (R = 0.88), 0.39% (R = 0.91) and 0.35 (R2 = 0.80), respectively in stalk and 0.72% (R = 0.88), 0.85% (R2 = 0.85) and 0.44 (R2 = 0.87), respectively in leaf. The model showed good performance in prediction of corresponding contents in unknown samples, however, no satisfying performance in ash content. (2) Both 2 mm and 0.5 mm grades of particle size can meet accuracy requirements of the model. But considering the time and labor cost, 2 mm grade was suggested for model building.


Asunto(s)
Biocombustibles , Celulosa/química , Lignina/química , Polisacáridos/química , China , Productos Agrícolas/química , Espectroscopía Infrarroja Corta
15.
J Am Chem Soc ; 137(7): 2436-9, 2015 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-25668069

RESUMEN

One approach toward optical nanoimaging involves sequential molecular localization of photoswitchable fluorophores to achieve high resolution beyond optical limit of diffraction. Block copolymer micelles assembled from polystryrene-block-poly(ethylene oxide) block copolymers (PSt-b-PEO) are visualized in optical nanoimaging by staining the polystyrene blocks with spiropyrans (SPs). SPs localized in hydrophobic phase of block copolymer micelles exhibit reversible fluorescence on-off switching at alternating irradiation of UV and visible light. Phase-selective distribution of SPs in block copolymer micelles enables optical nanoimaging of microphase structures of block copolymer self-assembly at 50-nm resolution. To date, this is the sturdiest realization of optical nanoimaging with subdiffraction resolution for solution self-assembly of block copolymers.


Asunto(s)
Nanotecnología/métodos , Imagen Óptica/métodos , Polímeros/química , Micelas
16.
Molecules ; 20(4): 5889-907, 2015 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-25854754

RESUMEN

The aim of this study was to develop and optimise a saikosaponin a and saikosaponin d compound liposome (SSa-SSd-Lip) formulation with reduced hemolysis and enhanced bioavailability. A screening experiment was done with Plackett-Burman design, and response surface methodology of five factors (EPC/SSa-SSd ratio, EPC/Chol ratio, water temperature, pH of PBS, and ultrasound time) was employed to optimise the mean diameter, entrapment efficiency of SSa and SSd, and the reduction of hemolysis for SSa-SSd-Lip. Under the optimal process conditions (EPC/SSa-SSd ratio, EPC/Chol ratio, water temperature and pH of PBS were 26.71, 4, 50 °C and 7.4, respectively), the mean diameter, the entrapment efficiency of SSa, the entrapment efficiency of SSd and the hemolysis were 203 nm, 79.87%, 86.19%, 25.16% (SSa/SSd 12.5 mg/mL), respectively. The pharmacokinetic studies showed that the SSa-SSd-Lip had increased circulation time, decreased Cl, and increased AUC, MRT and T1/2ß (p < 0.05) for both SSa and SSd after intravenous administration in comparison with solution.


Asunto(s)
Ácido Oleanólico/análogos & derivados , Saponinas/química , Saponinas/farmacocinética , Administración Intravenosa , Animales , Disponibilidad Biológica , Química Farmacéutica , Semivida , Hemólisis , Interacciones Hidrofóbicas e Hidrofílicas , Liposomas , Estructura Molecular , Ácido Oleanólico/administración & dosificación , Ácido Oleanólico/química , Ácido Oleanólico/farmacocinética , Tamaño de la Partícula , Conejos , Saponinas/administración & dosificación
17.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(1): 77-80, 2015 Jan.
Artículo en Zh | MEDLINE | ID: mdl-25616299

RESUMEN

Hennekam syndrome (HS) is a rare autosomal recessive syndrome characterized by defective lymphatic development. A 34-month-old boy with HS and who had unexplained developmental retardation and hypoalbuminemia as main clinical manifestations is reported here. He had a history of generalized edema and poor feeding. He was not thriving well. He manifested as facial anomalies (hypertelorism, flat nasal bridge and flat face), fracture of teeth, and superficial lymph nodes enlargement. He had low serum total protein, low serum albumin, and low serum immunoglobulin levels. Duodenal bulb biopsy revealed lymphangiectasia. Color Doppler ultrasound, magnetic resonance imaging and CT scan showed multi-site lymphangioma, and HS was thus confirmed. Mutations in CCBE1 and FAT4 have been found responsible for the syndrome in a part of patients. Diagnosis of the disease depends on the familial history, clinical signs, pathological findings and genetic tests.


Asunto(s)
Anomalías Craneofaciales/diagnóstico , Enfermedades de los Genitales Masculinos/diagnóstico , Linfangiectasia Intestinal/diagnóstico , Linfedema/diagnóstico , Preescolar , Anomalías Craneofaciales/etiología , Anomalías Craneofaciales/terapia , Enfermedades de los Genitales Masculinos/etiología , Enfermedades de los Genitales Masculinos/terapia , Humanos , Linfangiectasia Intestinal/etiología , Linfangiectasia Intestinal/terapia , Linfedema/etiología , Linfedema/terapia , Masculino , Síndrome
18.
Biomaterials ; 308: 122566, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38603824

RESUMEN

Achieving sufficient bone regeneration in large segmental defects is challenging, with the structure of bone repair scaffolds and their loaded bioactive substances crucial for modulating the local osteogenic microenvironment. This study utilized digital laser processing (DLP)-based 3D printing technology to successfully fabricate high-precision methacryloylated polycaprolactone (PCLMA) bionic bone scaffold structures. Adipose-derived stem cell-engineered nanovesicles (ADSC-ENs) were uniformly and stably modified onto the bionic scaffold surface using a perfusion device, constructing a conducive microenvironment for tissue regeneration and long bone defect repair through the scaffold's structural design and the vesicles' biological functions. Scanning electron microscopy (SEM) examination of the scaffold surface confirmed the efficient loading of ADSC-ENs. The material group loaded with vesicles (PCLMA-BAS-ENs) demonstrated good cell compatibility and osteogenic potential when analyzed for the adhesion and osteogenesis of primary rabbit bone marrow mesenchymal stem cells (BMSCs) on the material surface. Tested in a 15 mm critical rabbit radial defect model, the PCLMA-BAS-ENs scaffold facilitated near-complete bone defect repair after 12 weeks. Immunofluorescence and proteomic results indicated that the PCLMA-BAS-ENs scaffold significantly improved the osteogenic microenvironment at the defect site in vivo, promoted angiogenesis, and enhanced the polarization of macrophages towards M2 phenotype, and facilitated the recruitment of BMSCs. Thus, the PCLMA-BAS-ENs scaffold was proven to significantly promote the repair of large segmental bone defects. Overall, this strategy of combining engineered vesicles with highly biomimetic scaffolds to promote large-segment bone tissue regeneration holds great potential in orthopedic and other regenerative medicine applications.


Asunto(s)
Regeneración Ósea , Células Madre Mesenquimatosas , Osteogénesis , Impresión Tridimensional , Ingeniería de Tejidos , Andamios del Tejido , Animales , Conejos , Andamios del Tejido/química , Regeneración Ósea/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Ingeniería de Tejidos/métodos , Biónica , Poliésteres/química , Tejido Adiposo/citología
19.
Adv Sci (Weinh) ; 11(21): e2308381, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38447173

RESUMEN

3D bioprinting techniques have enabled the fabrication of irregular large-sized tissue engineering scaffolds. However, complicated customized designs increase the medical burden. Meanwhile, the integrated printing process hinders the cellular uniform distribution and local angiogenesis. A novel approach is introduced to the construction of sizable tissue engineering grafts by employing hydrogel 3D printing for modular bioadhesion assembly, and a poly (ethylene glycol) diacrylate (PEGDA)-gelatin-dopamine (PGD) hydrogel, photosensitive and adhesive, enabling fine microcage module fabrication via DLP 3D printing is developed. The PGD hydrogel printed micocages are flexible, allowing various shapes and cell/tissue fillings for repairing diverse irregular tissue defects. In vivo experiments demonstrate robust vascularization and superior graft survival in nude mice. This assembly strategy based on scalable 3D printed hydrogel microcage module could simplify the construction of tissue with large volume and complex components, offering promise for diverse large tissue defect repairs.


Asunto(s)
Hidrogeles , Ratones Desnudos , Impresión Tridimensional , Ingeniería de Tejidos , Andamios del Tejido , Animales , Ratones , Ingeniería de Tejidos/métodos , Hidrogeles/química , Andamios del Tejido/química , Gelatina/química , Bioimpresión/métodos , Polietilenglicoles/química , Neovascularización Fisiológica/fisiología , Dopamina/metabolismo , Regeneración/fisiología , Humanos
20.
J Biomed Sci ; 19: 73, 2012 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-22889374

RESUMEN

BACKGROUND: Enterovirus 71 (EV71) is a highly infectious agent that plays an etiological role in hand, foot, and mouth disease. It is associated with severe neurological complications and has caused significant mortalities in recent large-scale outbreaks. Currently, no effective vaccine or specific clinical therapy is available against EV71. METHODS: Unmodified 21 nucleotide small interfering RNAs (siRNAs) and classic 2'-modified (2'-O-methylation or 2'-fluoro modification) siRNAs were designed to target highly conserved 5' untranslated region (UTR) of the EV71 genome and employed as anti-EV71 agents. Real-time TaqMan RT-PCR, western blot analysis and plaque assays were carried out to evaluate specific viral inhibition by the siRNAs. RESULTS: Transfection of rhabdomyosarcoma (RD) cells with siRNAs targeting the EV71 genomic 5' UTR significantly delayed and alleviated the cytopathic effects of EV71 infection, increased cell viability in EV71-infected RD cells. The inhibitory effect on EV71 replication was sequence-specific and dosage-dependent, with significant corresponding decreases in viral RNA, VP1 protein and viral titer. Appropriate 2'-modified siRNAs exhibited similar RNA interference (RNAi) activity with dramatically increased serum stability in comparison with unmodified counterparts. CONCLUSION: Sequences were identified within the highly conserved 5' UTR that can be targeted to effectively inhibit EV71 replication through RNAi strategies. Appropriate 2'-modified siRNAs provide a promising approach to optimizing siRNAs to overcome barriers on RNAi-based antiviral therapies for broader administration.


Asunto(s)
Enterovirus Humano A/genética , Infecciones por Enterovirus , ARN Interferente Pequeño/genética , Replicación Viral/genética , Regiones no Traducidas 5'/genética , Línea Celular , Secuencia Conservada , Enterovirus Humano A/química , Infecciones por Enterovirus/genética , Infecciones por Enterovirus/terapia , Infecciones por Enterovirus/virología , Humanos , ARN Interferente Pequeño/química , Rabdomiosarcoma/genética , Rabdomiosarcoma/virología , Transfección
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