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1.
J Surg Res ; 270: 113-123, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34655937

RESUMEN

BACKGROUND: Prenatal surgical closure of Myelomeningocele (MMC) is considered part of the current age armamentarium. Clinical data has demonstrated the need for innovative patches to maximize the benefits and decrease the risks of this approach. Our team has developed a minimally invasive reverse thermal gel (RTG) patch with cellular scaffolding properties. Here, we demonstrate the initial gross and microscopic histological effects of this RTG patch in the fetal ovine model of MMC. MATERIALS AND METHODS: A fetal ovine MMC defect was created at 68-75 days gestation, RTG patch application or untreated at 100-103 days, and harvest at 135-140 days. The RTG was applied to the defect and secured in place with an overlay sealant. Defect areas underwent gross and microscopic analysis for inflammation and skin development. Brains were analyzed for hindbrain herniation and hydrocephalus. RESULTS: The untreated fetus (n = 1) demonstrated an open defect lacking tissue coverage, evidence of spinal cord injury, increased caspase-3, Iba1 and GFAP in spinal cord tissues, and hindbrain herniation and ventricular dilation. RTG treated fetuses (n = 3) demonstrated defect healing with well-organized dermal and epidermal layers throughout the entire healed tissue area overlaying the defect with minimal inflammation, reduced caspase-3, Iba1 and GFAP in spinal cord tissues, and no hindbrain herniation or ventricular dilation. CONCLUSION: An RTG patch applied to MMC defects in fetal sheep promoted skin coverage over the defect, was associated with minimal inflammation of the spinal cord tissues and prevented brain abnormalities. The present findings provide exciting results for future comprehensive radiological, functional, and mechanistic evaluation of the RTG.


Asunto(s)
Meningomielocele , Animales , Encéfalo , Femenino , Feto/cirugía , Meningomielocele/cirugía , Embarazo , Ovinos , Médula Espinal
2.
Arthroscopy ; 37(4): 1223-1232, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33242629

RESUMEN

PURPOSE: To present clinical results according to tunnel overlap in 1-stage anatomical revision anterior cruciate ligament reconstruction (ACLR). METHODS: All patients who underwent revision ACLR performed by a single surgeon (J.H.A.) from 2012 to 2017 and were followed up for >24 months were retrospectively evaluated. The exclusion criteria were concomitant ligament injury, including medial collateral ligament injury, modified Outerbridge grade ≥3 cartilage lesion, and severe meniscus defects. Tunnel overlap was measured on 3-dimensionally reconstructed computed tomography images. Patients in the nonoverlapped femoral tunnel group (group NO, n = 52) were treated with new tunnel drilling that completely avoided previous tunnels, and those in the overlapped femoral tunnel group (group O, n = 41) were treated with a new tunnel that overlapped with previous tunnels. Clinical outcomes were evaluated using the subjective International Knee Documentation Committee (IKDC) and Lysholm scores. Knee joint stability was measured using the Lachman and pivot shift tests. Patients with femoral tunnel widening of ≥14 mm underwent 2-stage ACLR. RESULTS: The mean follow-up duration of 93 patients was 46.9 months (range, 24-97 months). All preoperative subjective and objective IKDC (P<0.001) and Telos stress test scores (P = .016) were significantly improved at the last follow-up. Forty-one patients had overlapping femoral tunnels, whereas 87 had overlapping tibial tunnels. At the last follow-up, subjective IKDC and Lysholm scores (73.6 ± 15.3 vs 74.9 ± 12.1, P = .799 and 80.0 ± 19.2 vs 81.44 ± 13.5, P = .505, respectively) and objective pivot shift (IKDC grade) in the Lachman test (P = .183 and P = .450, respectively) did not differ significantly between groups NO and O, respectively. CONCLUSIONS: One-stage anatomical revision ACLR significantly improved the clinical results. Most tibial tunnels (94%) and approximately one-half (44%) of the femoral tunnels overlapped. The overlapped femoral tunnel group did not show inferior outcomes or stability. LEVEL OF EVIDENCE: Level III, cohort study.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior/patología , Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior , Fémur/cirugía , Tibia/cirugía , Adolescente , Adulto , Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Estudios de Cohortes , Femenino , Fémur/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Imagenología Tridimensional , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Masculino , Persona de Mediana Edad , Reoperación , Estudios Retrospectivos , Tibia/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven
3.
J Surg Res ; 251: 262-274, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32197182

RESUMEN

BACKGROUND: Myelomeningocele (MMC) is an open neural tube defect of the spinal column. Our laboratory previously introduced a reverse thermal gel (RTG) as the first in situ forming patch for in utero MMC application. To overcome the challenges of anchoring the RTG in the wet amniotic environment to improve MMC coverage, we modified the RTG to mimic the underwater adhesive properties of mussels. We have separated this study into three separate hypotheses-based components: CONCLUSIONS: The DRTG demonstrates increased elasticity, cellular scaffolding properties, and improved MMC coverage in the Grhl3 mouse model. Future studies will be translated to the preclinical ovine model to evaluate this novel gel.


Asunto(s)
Dopamina/química , Meningomielocele/terapia , Adhesivos Tisulares/uso terapéutico , Urea/uso terapéutico , Animales , Animales Recién Nacidos , Bivalvos/química , Proteínas de Unión al ADN/genética , Modelos Animales de Enfermedad , Femenino , Geles , Masculino , Ratones , Embarazo , Adhesivos Tisulares/química , Factores de Transcripción/genética , Urea/análogos & derivados , Urea/síntesis química
4.
J Surg Res ; 235: 227-236, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30691800

RESUMEN

BACKGROUND: Myelomeningocele (MMC) results in lifelong neurologic and functional deficits. Currently, prenatal repair of MMC closes the defect, resulting in a 50% reduction in postnatal ventriculoperitoneal shunting. However, this invasive fetal surgery is associated with significant morbidities to mother and baby. We have pioneered a novel reverse thermal gel (RTG) to cover MMC defects in a minimally invasive manner. Here, we test in-vitro RTG long-term stability in amniotic fluid and in vivo application in the Grainy head-like 3 (Grhl3) mouse MMC model. MATERIALS AND METHODS: RTG stability in amniotic fluid (in-vitro) was monitored for 6 mo and measured using gel permeation chromatography and solution-gel transition temperature (lower critical solution temperature). E16.5 Grhl3 mouse fetuses were injected with the RTG or saline and harvested on E19.5. Tissue was assessed for RTG coverage of the gross defect and inflammatory response by immunohistochemistry for macrophages. RESULTS: Polymer backbone molecular weight and lower critical solution temperature remain stable in amniotic fluid after 6 mo. Needle injection over the MMC of Grhl3 fetuses successfully forms a stable gel that covers the entire defect. On harvest, some animals demonstrate >50% RTG coverage. RTG injection is not associated with inflammation. CONCLUSIONS: Our results demonstrate that the RTG is a promising candidate for a minimally invasive approach to patch MMC. We are now poised to test our RTG patch in the large preclinical ovine model used to evaluate prenatal repair of MMC.


Asunto(s)
Materiales Biocompatibles/uso terapéutico , Fetoscopía , Meningomielocele/cirugía , Resinas Acrílicas , Animales , Femenino , Masculino , Ensayo de Materiales , Ratones , Procedimientos Quirúrgicos Mínimamente Invasivos , Embarazo
5.
Inorg Chem ; 58(17): 11389-11403, 2019 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-31433625

RESUMEN

We synthesized two new adenine-based Zn(II)/Cd(II) metal-organic frameworks (MOFs), namely, [Zn2(H2O)(stdb)2(5H-Ade)(9H-Ade)2]n (PNU-21) and [Cd2(Hstdb)(stdb)(8H-Ade)(Ade)]n (PNU-22), containing auxiliary dicarboxylate ligand (stdb = 4,4'-stilbenedicarboxylate). Both MOFs were characterized by multiple analytical techniques such as single-crystal X-ray diffraction (SXRD), powder X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, scanning electron microscopy, as well as temperature program desorption and Brunauer-Emmett-Teller measurements. Both MOFs were structurally robust and possessed unsaturated Lewis acidic metal centers [Zn(II) and Cd(II)] and free basic N atoms of adenine molecules. They were used as heterogeneous catalysts for the fixation of CO2 into five-membered cyclic carbonates. Significant conversion of epichlorohydrin (ECH) was attained at a low CO2 pressure (0.4 MPa) and moderate catalyst (0.6 mol %)/cocatalyst (0.3 mol %) amounts, with over 99% selectivity toward the ECH carbonate. They showed comparable or even higher catalytic activity than other previously reported MOFs. Because of high thermal stability and robust architecture of PNU-21/PNU-22, both catalysts could be reused with simple separation up to five successive cycles without any considerable loss of their catalytic activity. Densely populated acidic and basic sites in both Zn(II)/Cd(II) MOFs facilitated the conversion of ECH to ECH carbonate in high yields. The reaction mechanism of the cycloaddition reaction between ECH and CO2 is described by possible intermediates, transition states, and pathways, from the density functional theory calculation in correlation with the SXRD structure of PNU-21.

6.
Childs Nerv Syst ; 35(2): 343-348, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30171330

RESUMEN

PURPOSE: Increased serum biomakers, such as S100 calcium-binding protein B (S100B) and neuron-specific enolase (NSE), are associated with traumatic brain injury (TBI). The purpose of this study is to investigate the serum levels of S100B and NSE in pediatric TBI patients and to predict a clinical outcome. METHODS: Peripheral venous blood was collected within 6 h of injury and at 1 week to measure S100B and NSE. The serum S100B and NSE levels were measured using commercially available enzyme-linked immunosorbent assay kits. The authors divided participants into two groups at admission: a favorable group (patients with Glasgow Coma Scale [GCS] scores of 10-15) and an unfavorable group (patients with GCS scores of less than 9). Both S100B and NSE levels were compared between the two groups at the time of admission and 1 week later. RESULTS: Ten pediatric patients were enrolled (5 in the favorable group, 5 in the unfavorable group). The median serum S100B level of 134.21 pg/ml (range, 51.00-789.65 pg/ml) in patients with TBI at admission dropped to 41.49 pg/ml (range, 25.65-260.93 pg/ml) after 1 week, with significant differences between the traumatic event and 1 week later (p = 0.007). The median serum NSE level of 14.76 ng/ml (range, 6.48-21.23 ng/ml) in patients with TBI at admission was higher than that after 1 week (4.96 ng/ml, range, 3.01-31.21 ng/ml), with significant differences (p = 0.015). A significant difference was observed in S100B after 1 week between patients in the favorable and unfavorable groups (p = 0.047). One patient whose serum S100B and NSE levels were elevated 1 week after TBI eventually died. CONCLUSIONS: Elevated serum S100B and NSE levels in pediatric TBI patients decreased 1 week after traumatic events. The serum S100B level 1 week after TBI was related to the severity of brain damage. These results indicated that serum S100B and NSE might play a role in predicting the prognosis and monitoring ongoing brain injury in pediatric TBI patients.


Asunto(s)
Biomarcadores/sangre , Lesiones Traumáticas del Encéfalo/sangre , Fosfopiruvato Hidratasa/sangre , Subunidad beta de la Proteína de Unión al Calcio S100/sangre , Adolescente , Lesiones Traumáticas del Encéfalo/mortalidad , Niño , Femenino , Humanos , Masculino , Pronóstico , Estudios Prospectivos
7.
J Nanosci Nanotechnol ; 18(9): 6283-6287, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29677782

RESUMEN

The increasing role of catalysis by noble metals coupled with their high price requires the development of cheaper and more effective catalysts, e.g., highly dispersed supported catalyst. Herein, Pd supported on Al2O3 catalysts prepared by deposition-precipitation under different conditions were subjected to X-ray diffraction, N2-physisorption, NH3/CO2 temperature programmed desorption, CO-chemisorption, and field-emission transmission electron microscopy analyses, which revealed that the size and distribution of Pd particles were influenced by Al2O3 support type (particle size and phase transition) and preparation conditions (metal precursor type, pH value, and solution temperature). The Pd/Al2O3 catalysts were prepared using type A (particle size = 3 micron) or type B (particle size = 20 nm) as a support and PdCl2 (PC) or Pd(NO3)2·2H2O (PN) as a Pd precursor, respectively. In XRD results, type A (particle size = 3 micron) Al2O3 had γ and  phase, and type B (particle size = 20 nm) Al2O3 had only thermally stable γ phase. In addition, Pd dispersion and crystallite size showed an obvious dependence on pH value, solution temperature and attractive/repulsive forces between the functional groups of Al2O3 and Pd precursors. Optimal results were obtained using PdCl2 (PC) as a Pd precursor and type B (particle size = 20 nm) as a support at 60 °C and pH 5.5.

8.
Biomacromolecules ; 17(5): 1593-601, 2016 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-27073119

RESUMEN

Heart failure is a morbid disorder characterized by progressive cardiomyocyte (CM) dysfunction and death. Interest in cell-based therapies is growing, but sustainability of injected CMs remains a challenge. To mitigate this, we developed an injectable biomimetic Reverse Thermal Gel (RTG) specifically engineered to support long-term CM survival. This RTG biopolymer provided a solution-based delivery vehicle of CMs, which transitioned to a gel-based matrix shortly after reaching body temperature. In this study we tested the suitability of this biopolymer to sustain CM viability. The RTG was biomolecule-functionalized with poly-l-lysine or laminin. Neonatal rat ventricular myocytes (NRVM) and adult rat ventricular myocytes (ARVM) were cultured in plain-RTG and biomolecule-functionalized-RTG both under 3-dimensional (3D) conditions. Traditional 2D biomolecule-coated dishes were used as controls. We found that the RTG-lysine stimulated NRVM to spread and form heart-like functional syncytia. Regarding cell contraction, in both RTG and RTG-lysine, beating cells were recorded after 21 days. Additionally, more than 50% (p value < 0.05; n = 5) viable ARVMs, characterized by a well-defined cardiac phenotype represented by sarcomeric cross-striations, were found in the RTG-laminin after 8 days. These results exhibit the tremendous potential of a minimally invasive CM transplantation through our designed RTG-cell therapy platform.


Asunto(s)
Biomimética/métodos , Células Madre Embrionarias/citología , Laminina/química , Lisina/química , Miocitos Cardíacos/citología , Polímeros/química , Ingeniería de Tejidos/métodos , Animales , Animales Recién Nacidos , Células Cultivadas , Masculino , Ratas , Ratas Sprague-Dawley
9.
Macromol Rapid Commun ; 36(18): 1646-50, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26174587

RESUMEN

High molecular weight cyclic poly(ε-caprolactone)s (cPCLs) with variable ring size are synthesized via light-induced ring closure of α,ω-anthracene-terminated PCL (An-PCL-An). The ring size of cPCL is tunable simply by adjusting the polymer concentration from 10 to 100 mg mL(-1) in THF. The cyclo-addition via the bimolecular cyclization of An-PC-An is well characterized by a variety of analyses such as (1) H NMR and UV-vis spectroscopies, gel-permeation chromatography, and differential scanning calorimetry. The reversible dimerization of An induced by heating enables the cyclic PCL to have a switchable "on-off" capability. This novel light-induced ring-closure technique can be one of the most powerful candidates for producing various well-defined cyclic polymers in highly concentrated polymer solution.


Asunto(s)
Luz , Poliésteres/química , Poliésteres/síntesis química , Polímeros/química , Peso Molecular
10.
J Nanosci Nanotechnol ; 14(6): 4632-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24738441

RESUMEN

Bis(alkylimidazole) complexes of zinc, (RIm)2ZnX2, were prepared by a metal insertion reaction. The synthesized (RIm)2ZnX2 exhibited good catalytic performance during synthesis of glycerol carbonate (GC) from glycerol and urea. (HEIm)2ZnCl2 with a hydroxyl group exhibited the highest GC yield during glycerolysis of urea owing to incorporation of acid-base bifunctional active sites. (EIm)2ZnX2 catalysts based on different halide anions showed increased reactivity as Cl- < Br- < I-, which is the order of nucleophilicity. The effects of reaction parameters such as temperature, reaction time, catalyst loading, and degree of vacuum on the reactivity were also investigated.


Asunto(s)
Glicerol/química , Imidazoles/química , Nanoestructuras/química , Nanoestructuras/ultraestructura , Urea/química , Zinc/química , Catálisis , Esterificación , Compuestos Inorgánicos/química , Ensayo de Materiales , Compuestos Orgánicos/química , Tamaño de la Partícula
11.
J Nanosci Nanotechnol ; 14(6): 4551-6, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24738427

RESUMEN

A functionalized isoreticular metal organic framework material, F-IRMOF-3, having a quaternary ammonium group was prepared by fast precipitation and solvothermal method. The synthesized MOFs exhibited good catalytic performance in the synthesis of glycerol carbonate (GC) from glycerol and urea. F-IRMOF-3 having a larger alkyl chain structure and a more nucleophilic counter anion than the synthesized congeners, exhibited better reactivity in the synthesis of GC. The introduction of a ZnO defect into the F-IRMOF-3 structure by fast precipitation was more advantageous for the glycerolysis of urea than the conventional solvothermal method because of the incorporation of acid-base bifunctional active sites by the former method. The effects of reaction parameters such as temperature, reaction time, catalyst loading, and degree of vacuum on the reactivity were also investigated. The F-IRMOF-3 catalyst can be easily recovered and reused without considerable loss of its initial activity.


Asunto(s)
Carbonatos/síntesis química , Glicerol/química , Glicerol/síntesis química , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Urea/química , Óxido de Zinc/química , Catálisis , Ensayo de Materiales , Tamaño de la Partícula
12.
Matrix Biol Plus ; 22: 100148, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38803329

RESUMEN

The pancreatic islet is surrounded by ECM that provides both biochemical and mechanical cues to the islet ß-cell to regulate cell survival and insulin secretion. Changes in ECM composition and mechanical properties drive ß-cell dysfunction in many pancreatic diseases. While several studies have characterized changes in islet insulin secretion with changes in substrate stiffness, little is known about the mechanotransduction signaling driving altered islet function in response to mechanical cues. We hypothesized that increasing matrix stiffness will lead to insulin secretion dysfunction by opening the mechanosensitive ion channel Piezo1 and disrupting intracellular Ca2+ dynamics in mouse and human islets. To test our hypothesis, mouse and human cadaveric islets were encapsulated in a biomimetic reverse thermal gel (RTG) scaffold with tailorable stiffness that allows formation of islet focal adhesions with the scaffold and activation of Piezo1 in 3D. Our results indicate that increased scaffold stiffness causes insulin secretion dysfunction mediated by increases in Ca2+ influx and altered Ca2+ dynamics via opening of the mechanosensitive Piezo1 channel. Additionally, inhibition of Piezo1 rescued glucose-stimulated insulin secretion (GSIS) in islets in stiff scaffolds. Overall, our results emphasize the role mechanical properties of the islet microenvironment plays in regulating function. It also supports further investigation into the modulation of Piezo1 channel activity to restore islet function in diseases like type 2 diabetes (T2D) and pancreatic cancer where fibrosis of the peri-islet ECM leads to increased tissue stiffness and islet dysfunction.

13.
Fish Shellfish Immunol ; 35(4): 1209-15, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23911652

RESUMEN

Mammalian interleukin (IL)-15 plays an important role in the activation of CD8(+) T cells and natural killer (NK) cells along with its receptor α (IL-15Rα). To understand the potential roles of IL-15 and IL-15Rα in fish, we identified IL-15 and IL-15Rα cDNA from rock bream (Oplegnathus fasciatus) and investigated their gene expression profiles after bacterial and viral infection. Coding regions of rock bream (Rb) IL-15 and RbIL-15Rα cDNAs were 534 and 402 bp encoding 177 and 133 amino acid residues, respectively. The sushi domain of IL-15Rα was highly conserved between rock bream and other species. Unlike other IL-15Rαs, RbIL-15Rα does not have a transmembrane region. Gene expression of RbIL-15 and RbIL-15Rα was widely expressed in different tissues of healthy fish, especially immune-related tissues. RbIL-15 and RbIL-15Rα were highly induced in the kidney and spleen after infection with Edwardsiella tarda, Streptococcus iniae and red seabream iridovirus. Gene expression patterns of RbIL-15 and RbIL-15Rα were similar in the kidney and spleen after pathogen infection. However, these genes were differentially induced in the liver after pathogen infection. These results suggest that the different responses of RbIL-15 and RbIL-15Rα to pathogen infection may be induced by different tissues or cell types.


Asunto(s)
Proteínas de Peces/genética , Regulación de la Expresión Génica , Subunidad alfa del Receptor de Interleucina-15/genética , Interleucina-15/genética , Perciformes/genética , Perciformes/inmunología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN Complementario/genética , ADN Complementario/metabolismo , Edwardsiella tarda/fisiología , Proteínas de Peces/química , Proteínas de Peces/metabolismo , Inyecciones Intraperitoneales/veterinaria , Interleucina-15/metabolismo , Subunidad alfa del Receptor de Interleucina-15/metabolismo , Iridoviridae/fisiología , Datos de Secuencia Molecular , Especificidad de Órganos , Perciformes/metabolismo , Filogenia , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Alineación de Secuencia/veterinaria , Streptococcus/fisiología
14.
Phys Chem Chem Phys ; 15(23): 9029-33, 2013 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-23644632

RESUMEN

Microwave-assisted quaternization of glycine (GLY) resulted in the synthesis of an efficient catalyst, quaternized glycine (QGLY), for the solventless synthesis of cyclic carbonates from epoxides and CO2 under mild reaction conditions. Density functional theory was used to simulate the synergistic influence of the COOH group and the halide ion of QGLY in enhancing the catalytic activity.


Asunto(s)
Carbonatos/síntesis química , Glicina/análogos & derivados , Dióxido de Carbono/química , Catálisis , Ciclización , Compuestos Epoxi/química , Tecnología Química Verde , Modelos Moleculares
15.
J Nanosci Nanotechnol ; 13(3): 2230-5, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23755671

RESUMEN

A mixed-linker nanoporous coordination polymer Zn2(HIP)2(bipy)(H2O)2 x H2O (ZnHipBipy) constructed from polyfunctional linker 5-hydroxy isophthalic acid (HIP) and exo-bidentate ligand 4,4'-bipyridyl (bipy) was employed as heterogeneous catalyst for allyl glycidyl carbonate (AGC) synthesis from CO2 and allyl glycidyl ether (AGE) under solventless conditions. Besides being the organic linker, 5-hydroxy isophthalic acid enriches the functionality of the material through accessible hydroxyl group capable of contributing extensive hydrogen bonding interactions. The cycloaddition of CO2 and epoxide was catalyzed through a synergistic pathway offered by inherent hydroxyl group together with the catalytically active metal centre. Method of synthesis and texture of the catalyst were key factors in determining the conversion and selectivity. The effects of reaction parameters like catalyst amount, temperature, CO2 pressure and reaction time on the yield of AGC were also studied.


Asunto(s)
Dióxido de Carbono/química , Carbonatos/química , Compuestos Epoxi/química , Compuestos Inorgánicos/química , Compuestos Orgánicos/química , Catálisis
16.
J Nanosci Nanotechnol ; 13(3): 2307-12, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23755684

RESUMEN

Functionalized metal organic framework F-IRMOF-3 having quaternary ammonium group was prepared by a fast precipitation and solvothermal method. They showed good catalytic performance for the cycloaddition of allyl glycidyl ether (AGE) and carbon dioxide without any solvent. F-IRMOF-3 with a larger alkyl chain structure and more nucleophilic anion exhibited better reactivity for the cycloaddition reaction. The introduction of a defective ZnO to F-IRMOF-3 by the fast precipitation method becomes more advantageous than the conventional solvothermal method for the cycloaddition reaction due to acid-base bifunctional active sites. The F-IRMOF-3 can be easily recovered and reused without any considerable loss of initial activity.


Asunto(s)
Dióxido de Carbono/química , Compuestos Epoxi/química , Compuestos Orgánicos/química , Catálisis , Reacción de Cicloadición , Difracción de Rayos X
17.
Orthop J Sports Med ; 11(3): 23259671221143996, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36970316

RESUMEN

Background: The remnant preservation of a primary vertical graft in revision anterior cruciate ligament reconstruction (ACLR) can benefit anteroposterior stability. However, studies that address this concept are rare. Purpose: To evaluate clinical outcomes of remnant preservation of primary vertical graft in revision ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 74 patients with revision ACLR were included in this retrospective study. Remnant preservation revision ACLR was performed only in patients with primary vertical grafts. The patients were divided into 2 groups according to whether the primary remnant vertical graft was preserved (remnant group; n = 48) or absent or sacrificed (no-remnant group; n = 26). The remnant group was further divided according to the degree of remnant tissue: sufficiently preserved subgroup (graft coverage, ≥50%; n = 25) and insufficiently preserved subgroup (graft coverage, <50%; n = 23). Clinical outcomes were evaluated using the International Knee Documentation Committee (IKDC) subjective form, Lysholm score, Tegner activity scale, manual laxity tests, and side-to-side difference in anterior tibial translation on Telos stress radiographs. Results: The mean time to final follow-up was 40.7 ± 16.8 months. The remnant group showed more improved results in the postoperative Lachman test and Telos side-to-side difference than did the no-remnant group (P = .017 and .016, respectively). The post hoc test revealed that the side-to-side difference in laxity in the sufficiently preserved subgroup significantly outperformed that in the no-remnant group (P = .001), although no significant difference existed between the insufficiently preserved and no-remnant subgroups (P = .850). The postoperative IKDC subjective form, Lysholm score, and Tegner activity scale did not show significant differences between the 2 groups (P = .480, .277, and .883, respectively). Conclusion: The remnant preservation of the primary vertical graft in revision ACLR may result in better anteroposterior stability. However, subjective outcomes in the remnant group did not exceed that of the no-remnant group. The subgroup analysis revealed that only sufficiently preserved remnants demonstrated better anteroposterior stability.

18.
Scand J Infect Dis ; 44(6): 419-26, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22385095

RESUMEN

BACKGROUND: Surgical site infection (SSI) is a potentially morbid and costly complication of surgery. We conducted a multicentre case-control study to determine the risk factors for SSI in patients undergoing gastric surgery and to establish strategies to reduce the risk of SSI. METHODS: Between January 2007 and December 2008, 121 patients who developed an SSI after gastric surgery were matched with controls who had undergone surgery on the dates closest to those of the cases, at 13 centres in Korea. RESULTS: The results of multivariate analyses showed that the independent risk factors for SSI after gastric surgery were older age (p = 0.016), higher body mass index (BMI) (p = 0.033), male gender (p = 0.047), and longer duration of prophylactic antibiotic use (p < 0.001). CONCLUSION: Older age, higher BMI, male gender, and longer duration of prophylactic antibiotic use were independently associated with significant increases in the risk of SSI. Additional prospective randomized studies are required to confirm these results.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Gastropatías/cirugía , Infección de la Herida Quirúrgica/epidemiología , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , República de Corea/epidemiología , Factores de Riesgo
19.
Korean J Neurotrauma ; 18(1): 145-149, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35557638

RESUMEN

Spinal epidural arteriovenous fistula (SEDAVF) is a rare vascular malformation. Due to the mass effect of enlarged epidural veins and venous hypertension, progressive radiculopathy and myelopathy are likely to occur. A 33-year-old female presented with right upper extremity weakness for a month. The cause of this symptom was a SEDAVF, which was located near the C5-6-7 foramens and compressed the nerve roots. In the absence of intradural venous drainage, endovascular treatment is often difficult because of the large venous pouch. We performed endovascular trapping of the vertebral artery (VA) and loose packing of the coil material on the AVF to minimize mass effects. Immediately after embolization, the fistula was occluded, but a small new feeder vessel developed a day later. An n-butyl cyanoacrylate embolization was performed, and the fistula was successfully occluded.

20.
ACS Biomater Sci Eng ; 8(9): 3883-3898, 2022 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-35950643

RESUMEN

Myocardial infarction causes cardiomyocyte death and persistent inflammatory responses, which generate adverse pathological remodeling. Delivering therapeutic proteins from injectable materials in a controlled-release manner may present an effective biomedical approach for treating this disease. A thermoresponsive injectable gel composed of chitosan, conjugated with poly(N-isopropylacrylamide) and sulfonate groups, was developed for spatiotemporal protein delivery to protect cardiac function after myocardial infarction. The thermoresponsive gel delivered vascular endothelial growth factor (VEGF), interleukin-10 (IL-10), and platelet-derived growth factor (PDGF) in a sequential and sustained manner in vitro. An acute myocardial infarction mouse model was used to evaluate polymer biocompatibility and to determine therapeutic effects from the delivery system on cardiac function. Immunohistochemistry showed biocompatibility of the hydrogel, while the controlled delivery of the proteins reduced macrophage infiltration and increased vascularization. Echocardiography showed an improvement in ejection fraction and fractional shortening after injecting the thermal gel and proteins. A factorial design of experimental study was implemented to optimize the delivery system for the best combination and doses of proteins for further increasing stable vascularization and reducing inflammation using a subcutaneous injection mouse model. The results showed that VEGF, IL-10, and FGF-2 demonstrated significant contributions toward promoting long-term vascularization, while PDGF's effect was minimal.


Asunto(s)
Infarto del Miocardio , Factor A de Crecimiento Endotelial Vascular , Animales , Hidrogeles/farmacología , Hidrogeles/uso terapéutico , Interleucina-10/uso terapéutico , Ratones , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/patología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/uso terapéutico
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