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1.
J Food Sci Technol ; 56(5): 2712-2720, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31168153

RESUMEN

Buckwheat hulls, generally discarded as waste, have been known to possess various flavonoids and high antioxidant activities. The objective of this study was to determine effect of extracting solvents [water, ethanol (20%, 50%, 80%, and 100%), methanol, and acetone] on total phenolic content, flavonoid content and composition, and antioxidant activities of common and tartary buckwheat hull extracts. Antioxidative effect of common and tartary buckwheat hull extracts on lipids in mayonnaise was also investigated. Vitexin, isovitexin, isoorientin, orientin, rutin, isoquercetin, and quercetin were identified in the common buckwheat hull extracts, while rutin, quercetin, isoorientin, and isoquercetin were in the tartary buckwheat hull extracts. The methanol and 80% ethanol extracts had more flavonoids than the others, while the aqueous ethanol extracts from both of the hulls had more total phenolics and antioxidant activities. Oxidative stability of lipids in mayonnaises added with common and tartary buckwheat hull extracts (0.02 and 0.08%, w/w) prepared by 50% ethanol were higher than that in the mayonnaise with butylated hydroxytoluene (0.02%) and control. Oxidative stability was not significantly different between the mayonnaises added with the two buckwheat hull extracts.

2.
J Org Chem ; 79(14): 6444-55, 2014 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-24979530

RESUMEN

A tandem protocol for the synthesis of fluorinated isoxazoles has been developed via catalytic intramolecular cyclizations of 2-alkynone O-methyl oximes and ensuing fluorination. The reactions proceed smoothly at room temperature in the presence of 5 mol % of (IPr)AuCl, 5 mol % of AgOTs, 2.5 equiv of Selectfluor, and 2 equiv of NaHCO3. This process features an efficient one-pot cascade route to fluoroisoxazoles with high yields and high selectivity under mild reaction conditions.


Asunto(s)
Hidrocarburos Fluorados/síntesis química , Isoxazoles/síntesis química , Compuestos Orgánicos de Oro/química , Oximas/química , Catálisis , Ciclización , Hidrocarburos Fluorados/química , Isoxazoles/química , Estructura Molecular
3.
Pharmaceutics ; 13(4)2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33918329

RESUMEN

Red ginseng (RG) and black ginseng (BG, CJ EnerG) were prepared from fresh ginseng using one and nine cycles of steaming and drying, respectively. This process reduces the molecular weight (MW) of ginsenoside-active compounds in ginseng by removing sugar moieties from their dammaranes. We compared the pharmacokinetic characteristics of ginsenosides between BG comprising mainly low-MW ginsenosides (Rg3, Rg5, Rk1, and Rh1) and RG that predominantly contains high-MW ginsenosides (Rb1, Rb2, Rc, Rd, Re, and Rg1). The safety profiles and tolerability were also studied using a randomized, double-blind, single-dose, crossover clinical trial. A combination of Rb1, Rg1, and Rg3, well-known representative and functional RG components, exhibited a 1 h faster absorption rate (Tmax) and 58% higher exposure (24 h area under the concentration-time curve, AUC24) in BG than in RG. Furthermore, the combination of Rg3, Rg5, and Rk1, the major and most efficient components in BG, displayed 824% higher absorption (AUC24) in BG than in RG. The total ginsenoside showed a 5 h rapid intestinal absorption (Tmax) and 79% greater systemic exposure (AUC24) in BG than in RG. No clinically significant findings were observed in terms of safety or tolerability. Thus, BG extract was more effective than RG extract.

4.
Vasc Endovascular Surg ; 52(1): 52-58, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29162024

RESUMEN

High-definition fluoroscopic imaging is required to perform endovascular procedures safely and precisely, especially in complex cases, resulting in longer procedures and increased radiation exposure. This is of importance for training institutions as trainees, even with sound instruction in as low as reasonably achievable (ALARA) principles, tend to have high radiation exposures. Recently, there was an upgrade in the imaging system allowing for comparison of radiation exposure to patients and providers. We performed an analysis of consecutive endovascular aneurysm repair (EVAR) and superficial femoral artery (SFA) interventions in the years 2013 to 2014. We recorded body mass index (BMI) and fluoroscopy time (FT) and subsequently matched 1:1 based on BMI, FT, or both. We determined radiation dose using air kerma (AK) and also recorded individual surgeons' badge readings. Allura Xper FD20 was upgraded to AlluraClarity with ClarityIQ. We identified a total of 77 EVARs (52 pre and 25 post) and 134 SFA interventions (99 pre and 35 post). Unmatched results for EVAR were BMI pre 26.2 versus post 25.8 (kg/m2, P = .325), FT 28.1 versus 21.2 (minutes, P = .051), and AK 1178.5 versus 581 (mGy, P < .001), respectively. After matching, there was a 53.2% reduction in AK (846.1 vs 395.9 mGy; P = .004) for EVAR. Unmatched results for SFA interventions were BMI pre 28.1 versus post 26.6 ( P = .327), FT 18.7 versus 16.2 ( P = .282), and AK 285.6 versus 106.0 ( P < .001), respectively. After matching, there was a 57.0% reduction in AK (305.0 vs 131.3, P < .001). The total deep dose equivalent from surgeons' badge readings decreased from 39.5 to 17 mrem ( P = .029). Aortic and peripheral endovascular interventions can be performed with reduced radiation exposure to patients and providers, employing modern fixed imaging systems with advanced dose reduction technology. This is of particular importance in the light of the increasing volume and complexity of endovascular and hybrid procedures as well as the prospect of decades of radiation exposure during training and practice.


Asunto(s)
Aneurisma de la Aorta Abdominal/terapia , Procedimientos Endovasculares/instrumentación , Arteria Femoral/diagnóstico por imagen , Exposición Profesional/prevención & control , Salud Laboral , Seguridad del Paciente , Enfermedad Arterial Periférica/terapia , Dosis de Radiación , Exposición a la Radiación/prevención & control , Radiografía Intervencional/instrumentación , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Índice de Masa Corporal , Procedimientos Endovasculares/efectos adversos , Diseño de Equipo , Femenino , Fluoroscopía , Humanos , Masculino , Exposición Profesional/efectos adversos , Enfermedad Arterial Periférica/diagnóstico por imagen , Exposición a la Radiación/efectos adversos , Monitoreo de Radiación/instrumentación , Radiografía Intervencional/efectos adversos , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Carga de Trabajo
5.
AJNR Am J Neuroradiol ; 38(3): 442-449, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28104643

RESUMEN

BACKGROUND AND PURPOSE: Advancements in medical device and imaging technology as well as accruing clinical evidence have accelerated the growth of the endovascular treatment of cerebrovascular diseases. However, the augmented role of these procedures raises concerns about the radiation dose to patients and operators. We evaluated patient doses from an x-ray imaging platform with radiation dose-reduction technology, which combined image noise reduction, motion correction, and contrast-dependent temporal averaging with optimized x-ray exposure settings. MATERIALS AND METHODS: In this single-center, retrospective study, cumulative dose-area product inclusive of fluoroscopy, angiography, and 3D acquisitions for all neurovascular procedures performed during a 2-year period on the dose-reduction platform were compared with a reference platform. Key study features were the following: The neurointerventional radiologist could select the targeted dose reduction for each patient with the dose-reduction platform, and the statistical analyses included patient characteristics and the neurointerventional radiologist as covariates. The analyzed outcome measures were cumulative dose (kerma)-area product, fluoroscopy duration, and administered contrast volume. RESULTS: A total of 1238 neurointerventional cases were included, of which 914 and 324 were performed on the reference and dose-reduction platforms, respectively. Over all diagnostic and neurointerventional procedures, the cumulative dose-area product was significantly reduced by 53.2% (mean reduction, 160.3 Gy × cm2; P < .0001), fluoroscopy duration was marginally significantly increased (mean increase, 5.2 minutes; P = .0491), and contrast volume was nonsignificantly increased (mean increase, 15.3 mL; P = .1616) with the dose-reduction platform. CONCLUSIONS: A significant reduction in patient radiation dose is achievable during neurovascular procedures by using dose-reduction technology with a minimal impact on workflow.


Asunto(s)
Angiografía de Substracción Digital/métodos , Angiografía Cerebral/métodos , Trastornos Cerebrovasculares/cirugía , Procedimientos Endovasculares/métodos , Radiografía Intervencional/métodos , Anciano , Trastornos Cerebrovasculares/diagnóstico por imagen , Femenino , Fluoroscopía/métodos , Humanos , Masculino , Persona de Mediana Edad , Dosis de Radiación , Exposición a la Radiación , Estudios Retrospectivos , Rayos X
6.
Biochim Biophys Acta ; 1425(2): 419-24, 1998 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-9795258

RESUMEN

The fungal cell wall is a supramolecular network of glycoproteins and polysaccharides. Its analysis is seriously hampered by the lack of easily available hydrolytic enzymes in a pure form. Here we describe a simple and efficient purification procedure of a recombinant beta-(1-6)-glucanase from Trichoderma harzianum expressed in Pichia pastoris. Transformed cells efficiently secreted the enzyme into the induction medium. We purified the enzyme using a one-step method based on hydrophobic interaction chromatography. The yield was 80%. SDS-PAGE of the purified enzyme revealed a single band with an apparent molecular mass of 43 kDa. The isoelectric point of the enzyme was 5.8, and it showed maximal enzyme activity and stability at pH 5.0. As beta-(1-6)-glucan is an important component of fungal cell walls, the easy availability of pure beta-(1-6)-glucanase will highly facilitate studies of the molecular organization of the fungal cell wall.


Asunto(s)
Glicósido Hidrolasas/aislamiento & purificación , Pichia/enzimología , Trichoderma/enzimología , Membrana Celular/química , Estabilidad de Enzimas , Glicósido Hidrolasas/biosíntesis , Glicósido Hidrolasas/química , Concentración de Iones de Hidrógeno , Pichia/genética , Proteínas Recombinantes/aislamiento & purificación , Trichoderma/genética
7.
AJNR Am J Neuroradiol ; 36(1): 146-52, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25273534

RESUMEN

BACKGROUND AND PURPOSE: Although myeloperoxidase activity in vivo can be visualized by using noninvasive imaging, successful clinical translation requires further optimization of the imaging approach. We report a motion-sensitized driven-equilibrium MR imaging approach for the detection of a myeloperoxidase activity-specific gadolinium-containing imaging agent in experimental aneurysm models, which compensates for irregular blood flow, enabling vascular wall imaging in the aneurysm. MATERIALS AND METHODS: A phantom was built from rotational angiography of a rabbit elastase aneurysm model and was connected to a cardiac pulse duplicator mimicking rabbit-specific flow conditions. A T1-weighted turbo spin-echo-based motion-sensitized driven-equilibrium pulse sequence was optimized in vitro, including the addition of fat suppression and the selection of the velocity-encoding gradient parameter. The optimized sequence was applied in vivo to rabbit aneurysm models with and without inflammation in the aneurysmal wall. Under each condition, the aneurysms were imaged before and after intravenous administration of the imaging agent. The signal-to-noise ratio of each MR imaging section through the aneurysm was calculated. RESULTS: The motion-sensitized driven-equilibrium sequence was optimized to reduce flow signal, enabling detection of the myeloperoxidase imaging agent in the phantom. The optimized imaging protocol in the rabbit model of saccular aneurysms revealed a significant increase in the change of SNR from pre- to post-contrast MR imaging in the inflamed aneurysms compared with naïve aneurysms and the adjacent carotid artery (P < .0001). CONCLUSIONS: A diagnostic MR imaging protocol was optimized for molecular imaging of a myeloperoxidase-specific molecular imaging agent in an animal model of inflamed brain aneurysms.


Asunto(s)
Aumento de la Imagen/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Angiografía por Resonancia Magnética/métodos , Neuroimagen/métodos , Peroxidasa , Animales , Modelos Animales de Enfermedad , Gadolinio DTPA , Masculino , Movimiento (Física) , Fantasmas de Imagen , Conejos , Radiografía , Relación Señal-Ruido
8.
Neurosci Lett ; 303(3): 145-8, 2001 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-11323106

RESUMEN

We investigated whether in healthy subjects L-tryptophan may serve as a precursor for the endogenous synthesis of the beta-carboline norharman. For this purpose subjects, smokers as well as non-smokers, received 0 or 1.2 g of an oral dose of tryptophan. Smokers started the experiment 2 h after cessation of smoking. Plasma levels of tryptophan and norharman were measured 100 and 125 min after the start of the experiment. The levels of both compounds were significantly higher in the group receiving tryptophan. Norharman concentrations in the plasma of smokers were significantly higher than in the non-smoking subjects under both experimental conditions. These results add some proof to the hypothesis that in humans tryptophan may serve as a precursor for the synthesis of norharman.


Asunto(s)
Harmina/sangre , Fumar/sangre , Triptófano/sangre , Adolescente , Adulto , Carbolinas , Cromatografía Líquida de Alta Presión , Femenino , Harmina/análogos & derivados , Humanos , Masculino
9.
Life Sci ; 69(18): 2113-21, 2001 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-11669455

RESUMEN

In healthy subjects, pharmacokinetics were characterised using single oral and sublingual administrations of the beta-carboline norharman. For this purpose, norharman levels in blood plasma were measured up to 90-105 min after both routes of administration. Dose proportionality of three different single oral doses of norharman (7, 65 and 110 microg/kg) administered as 0.52 and 5 mg capsules was evaluated at 8 time points. Peak levels were attained at 30 min after the oral load of norharman. Mean relative availabilities determined by the area under the curve (AUC) procedure were 14.3 and 98.0 nmol.min/l after oral dosing of 7 and 65 microg/kg, respectively. AUC values in women were 3-4 times higher than in men. Sublingual dosing of 6.5 and 13 microg/kg norharman encapsulated in 5 mg of cyclodextrins resulted in a much higher mean AUC and a more rapid absorption. Mean AUC after sublingual administration of 6.5 microg/kg was 929.8 nmol.min/kg and plasma levels were maximal 10-15 min after norharman was given. Moreover, apparently no sex difference was found using this way of application. Norharman disappeared from the plasma with half-lifes of 25-35 min, irrespective of the route of administration. Even at the highest measured norharman levels of 53 nmol/l plasma, no behavioral effects were observed. In addition, the subjects did neither report any effects nor any side-effects during the experiment. This is the first study in which the kinetics of ingested norharman have been measured in humans.


Asunto(s)
Carbolinas/farmacocinética , Harmina/análogos & derivados , Harmina/farmacocinética , Mutágenos/farmacocinética , Administración Oral , Adulto , Carbolinas/administración & dosificación , Femenino , Harmina/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Mutágenos/administración & dosificación
10.
J Chromatogr A ; 808(1-2): 133-9, 1998 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-9652115

RESUMEN

Purification of alpha-galactosidase from the roots of Verbascum thapsus L. was difficult to achieve using conventional methods due to the presence of coloured contaminants. A newly developed procedure, hybrid affinity chromatography, which was based on a mixed matrix separation procedure, using a substrate analogue and an immobilized metal affinity matrix as ligands, respectively, allowed the purification of this enzyme with good recovery. The method should be applicable to other proteins as well.


Asunto(s)
Cromatografía de Afinidad/métodos , Plantas/enzimología , alfa-Galactosidasa/aislamiento & purificación , Concanavalina A , Electroforesis en Gel de Poliacrilamida , Focalización Isoeléctrica , Punto Isoeléctrico , Lectinas de Plantas , Raíces de Plantas/enzimología
11.
Kardiologiia ; 19(1): 58-63, 1979 Jan.
Artículo en Ruso | MEDLINE | ID: mdl-312355

RESUMEN

The work is based on the analysis of data on 20 patients with acute myocardial infarction who underwent emergency operations for aorticocoronary shunting and on the findings of 50 dog experiments. Comparison of experimental and clinical data showed that the extrapolation of experimental parameters to a sick person should be undertaken with caution and with a greater probability for groups of patients suffering from myocarial infarction for the first time and with no chronic ischemic heart disease. A time period of six hours from the moment symptoms of myocardial infarction develop is the optimum term for emergency aorticocoronary shunting. A successful operation, however, is also possible at later periods, 15 to 18 hours form the time myocardial infarction develops.


Asunto(s)
Puente de Arteria Coronaria , Enfermedad Coronaria/cirugía , Vasos Coronarios/cirugía , Urgencias Médicas , Enfermedad Aguda , Adulto , Anciano , Animales , Circulación Coronaria , Perros , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Lactatos/metabolismo , Masculino , Persona de Mediana Edad , Contracción Miocárdica , Miocardio/metabolismo , Fosforilasas/metabolismo , Factores de Tiempo
12.
AJNR Am J Neuroradiol ; 34(11): 2163-70, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23721899

RESUMEN

BACKGROUND AND PURPOSE: Developments in flat panel angiographic C-arm systems have enabled visualization of both the neurovascular stents and host arteries in great detail, providing complementary spatial information in addition to conventional DSA. However, the visibility of these structures may be impeded by artifacts generated by adjacent radio-attenuating objects. We report on the use of a metal artifact reduction algorithm for high-resolution contrast-enhanced conebeam CT for follow-up imaging of stent-assisted coil embolization. MATERIALS AND METHODS: Contrast-enhanced conebeam CT data were acquired in 25 patients who underwent stent-assisted coiling. Reconstructions were generated with and without metal artifact reduction and were reviewed by 3 experienced neuroradiologists by use of a 3-point scale. RESULTS: With metal artifact reduction, the observers agreed that the visibility had improved by at least 1 point on the scoring scale in >40% of the cases (κ = 0.6) and that the streak artifact was not obscuring surrounding structures in 64% of all cases (κ = 0.6). Metal artifact reduction improved the image quality, which allowed for visibility sufficient for evaluation in 65% of the cases, and was preferred over no metal artifact reduction in 92% (κ = 0.9). Significantly higher scores were given with metal artifact reduction (P < .0001). CONCLUSIONS: Although metal artifact reduction is not capable of fully removing artifacts caused by implants with high x-ray absorption, we have shown that the image quality of contrast-enhanced conebeam CT data are improved drastically. The impact of the artifacts on the visibility varied between cases, and yet the overall visibility of the contrast-enhanced conebeam CT with metal artifact reduction improved in most the cases.


Asunto(s)
Artefactos , Tomografía Computarizada de Haz Cónico/instrumentación , Tomografía Computarizada de Haz Cónico/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Stents , Pantallas Intensificadoras de Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Prótesis Vascular , Humanos , Persona de Mediana Edad , Intensificación de Imagen Radiográfica/instrumentación , Intensificación de Imagen Radiográfica/métodos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad
13.
J Huntingtons Dis ; 2(1): 41-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-25063428

RESUMEN

Our goal is delivery of a long-term treatment for Huntington's disease. We administer intracerebrally in sheep adeno-associated virus (AAV) to establish optimal safety, spread and neuronal uptake of AAV based therapeutics. Sheep have large gyrencephalic brains and offer the opportunity to study a transgenic Huntington's disease model. However, lack of a relevant brain stereotactic atlas and the difficulty of skull fixation make conventional stereotaxy unreliable. We describe a multi-modal image-guidance technique to achieve accurate placement of therapeutics into the sheep striatum.


Asunto(s)
Cuerpo Estriado/cirugía , Modelos Animales de Enfermedad , Terapia Genética/métodos , Vectores Genéticos/administración & dosificación , Enfermedad de Huntington , Animales , Animales Modificados Genéticamente , Convección , Cuerpo Estriado/anatomía & histología , Dependovirus , Enfermedad de Huntington/terapia , Oveja Doméstica , Técnicas Estereotáxicas
14.
AJNR Am J Neuroradiol ; 33(2): 353-8, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22173756

RESUMEN

BACKGROUND AND PURPOSE: Previous studies have shown the feasibility of assessing qualitative CBV measurements in the angiography suite by using FPD-CBCT systems. We have investigated the correlation of FPD-CBCT CBV lesion volumes to the infarct volume. MATERIALS AND METHODS: Unilateral strokes were created in 7 adult dogs. MR imaging and FPD-CBCT data were obtained after MCA occlusion. FPD-CBCT CBV and ADC maps were generated for all subjects. The animals were sacrificed immediately following the last imaging study to measure infarct volume on histology. The reliability of FPD-CBCT-based lesion volume measurements was compared with those measured histologically by using regression and Bland-Altman analysis. RESULTS: The best correlation (R(2) = 0.72) between lesion volumes assessed with FPD-CBCT and histology was established with a threshold of mean healthy CBV - 2.5 × SD. These results were inferior to the correlation of lesion volumes measured with ADC and histology (R(2) = 0.99). Bland-Altman analysis showed that the agreement of ADC-derived lesion volumes with histology was superior to the agreement of FPD-CBCT-derived lesion volumes with histology. CONCLUSIONS: We correlated FPD-CBCT measurements of CBV and MR ADC lesion volumes with histologically assessed infarct volume. As expected, ADC is a very accurate and precise method for determining the extent of infarction. FPD-CBCT CBV lesion volumes are correlated to the size of the infarct. Improvement of FPD-CBCT image quality provides an opportunity to establish quantitative CBV measurement in the angiography suite.


Asunto(s)
Volumen Sanguíneo , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/fisiopatología , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/fisiopatología , Tomografía Computarizada por Rayos X , Animales , Modelos Animales de Enfermedad , Perros
15.
AJNR Am J Neuroradiol ; 33(4): 655-60, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22194374

RESUMEN

BACKGROUND AND PURPOSE: Intracranial aneurysms treated by coiling have a risk for recurrence, requiring surveillance imaging. MRA has emerged as an attractive technique for postcoiling aneurysm imaging. Previous research has evaluated MR imaging artifacts of the coil mass in vitro. Our aim in this study was to evaluate MR imaging artifacts of coiled aneurysms in vivo with time. MATERIALS AND METHODS: Four sidewall aneurysms were created in each of 4 dogs. Aneurysms were embolized receiving only 1 type of coils. After embolization, the animals were transferred to MR imaging, which included axial 3D TOF MRA (TEs, 3.5, 5, and 6.9 ms), phase-contrast MRA, and coronal CE-MRA. MR imaging studies were repeated at 1, 4, 6, 8, 14, and 28 weeks. We calculated an OEF: OEF = V(A)/V(CM), where the numerator represents the volume of the MR imaging artifacts and the denominator is the true volume of the coil mass measured by 3D RA. RESULTS: OEFs were largest immediately after embolization and showed a gradual decay until approximately 4 weeks, when there was stabilization of the size of the artifacts. By 4 weeks, there was mild coil compaction (average coil mass volume decrease of 7.8%); however, the OEFs decreased by 25% after 4 weeks (P < .001). CONCLUSIONS: MR imaging susceptibility artifacts change with time, being maximal in the postembolization setting and decaying until 4 weeks. The clinical implications of this study are that baseline MRA for comparison with future imaging should be acquired at a minimum of 1 week after the procedure.


Asunto(s)
Artefactos , Modelos Animales de Enfermedad , Aumento de la Imagen/métodos , Aneurisma Intracraneal/patología , Aneurisma Intracraneal/cirugía , Angiografía por Resonancia Magnética/métodos , Trombolisis Mecánica/instrumentación , Animales , Perros , Femenino , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
AJNR Am J Neuroradiol ; 33(9): 1657-62, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22538075

RESUMEN

BACKGROUND AND PURPOSE: Recently, the use of stents to assist in the coiling and repair of wide-neck aneurysms has been shown to be highly effective; however, the effect of these stents on the RC of the parent vessel has not been quantified. The purpose of this study was to quantify the effect of intracranial stenting on the RC of the implanted artery using 3D datasets. MATERIALS AND METHODS: Twenty-four patients receiving FDA-approved neurovascular stents to support coil embolization of brain aneurysms were chosen for this study. The stents were located in the ICA, ACA, or MCA. We analyzed C-arm rotational angiography and contrast-enhanced cone beam CT datasets before and after stent implantation, respectively, to ascertain changes in vessel curvature. The images were reconstructed, and the vessel centerline was extracted. From the centerline, the RC was calculated. RESULTS: The average implanted stent length was 25.4 ± 5.8 mm, with a pre-implantation RC of 7.1 ± 2.1 mm and a postimplantation RC of 10.7 ± 3.5 mm. This resulted in a 3.6 ± 2.7 mm change in the RC due to implantation (P < .0001), more than a 50% increase from the pre-implantation value. There was no difference in the change of RC for the different locations studied. The change in RC was not impacted by the extent of coil packing within the aneurysm. CONCLUSIONS: The implantation of neurovascular stents can be shown to have a large impact on the RC of the vessel. This will lead to a change in the local hemodynamics and flow pattern within the aneurysm.


Asunto(s)
Prótesis Vascular , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Trombolisis Mecánica/instrumentación , Trombolisis Mecánica/métodos , Stents , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Implantación de Prótesis/métodos , Radiografía , Resultado del Tratamiento , Adulto Joven
17.
J Appl Bacteriol ; 60(6): 483-90, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3528110

RESUMEN

Strains of Clostridium botulinum type A, type E and both non-proteolytic and proteolytic types B and F were characterized by their electrophoretic protein patterns. As the protein pattern changes during sporulation, special attention was paid to the prevention of sporulation by selecting an appropriate medium (Strasdine's medium plus 1% w/v glucose) and a scheme of repeated subculturing. Ribosomal proteins, evolutionarily conservative and hence relatively similar in all types of bacteria, were removed to optimize the resolving power of the electrophoretic technique. Protein patterns were compared by computing correlation coefficients of normalized densitometric tracings. The method is highly reproducible and its resolving power is high: all protein patterns found were specific. The strains tested fall into two main groups: the proteolytic and the non-proteolytic cluster. Type A strains form a separate subgroup within the proteolytic cluster, the same applies to type E strains within the non-proteolytic group. Although time-consuming for spore-forming bacteria, this method is, to our knowledge, the only technique that recognizes individual strains of Cl. botulinum. For non-spore-forming micro-organisms the method is certainly much simpler and hence even more valuable.


Asunto(s)
Proteínas Bacterianas/análisis , Clostridium botulinum/clasificación , Proteínas Ribosómicas/análisis , Clostridium botulinum/fisiología , Medios de Cultivo , Densitometría , Electroforesis Discontinua , Esporas Bacterianas
18.
FEMS Yeast Res ; 1(3): 187-94, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12702343

RESUMEN

Glycosylphosphatidylinositol (GPI)-dependent cell wall proteins in yeast are connected to the beta-1,3-glucan network via a beta-1,6-glucan moiety. Addition of gentiobiose or beta-1,6-glucan oligomers to growing cells affected the construction of a normal layer of GPI-dependent cell wall proteins at the outer rim of the Saccharomyces cerevisiae cell wall. Treated S. cerevisiae cells secreted significant amounts of cell wall protein 2, were much more sensitive to the lytic action of zymolyase 20T and displayed a marked increase in sensitivity to the small amphipathic antimicrobial peptide MB-21. Similar results in terms of sensitization of yeast cells to the antimicrobial peptide were obtained with the notorious food spoilage yeast Zygosaccharomyces bailii. Our results indicate that treating cells with a membrane-perturbing compound together with compounds that lead to an impaired construction of a normal GPI-dependent yeast wall protein layer represents an effective strategy to prevent the growth of major food spoilage yeasts.


Asunto(s)
Oligosacáridos/farmacología , Péptidos/farmacología , Saccharomyces cerevisiae/efectos de los fármacos , Zygosaccharomyces/efectos de los fármacos , beta-Glucanos , Antifúngicos/farmacología , Péptidos Catiónicos Antimicrobianos , Membrana Celular/efectos de los fármacos , Pared Celular/efectos de los fármacos , Pared Celular/metabolismo , Disacáridos/farmacología , Microbiología de Alimentos , Glucanos/química , Glicosilfosfatidilinositoles/metabolismo , Hidrolasas/farmacología , Proteínas de la Membrana/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Oligosacáridos/química , Polisacáridos/farmacología , Saccharomyces cerevisiae/crecimiento & desarrollo , Zygosaccharomyces/crecimiento & desarrollo
19.
Cell ; 37(2): 629-33, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6327079

RESUMEN

Various maturation forms of the plant protein thaumatin were expressed in yeast, using a promoter fragment of the glyceraldehyde- 3P -dehydrogenase (GAPDH) gene. Plasmids encoding preprothaumatin were shown to direct the synthesis of a processed form of the plant protein. The important role of signal sequences in the expression of the plant protein in yeast was indicated by the observation that plasmids encoding processed thaumatin forms were only poorly expressed, if at all. Nucleotide sequence analysis of the 843 nucleotide GAPDH promoter fragment revealed a characteristic structure with two regions of dyad symmetry containing translational starts of GAPDH and a putative 38 amino acid peptide. A promoter fragment from which the upstream region was deleted proved to be less efficient in thaumatin expression.


Asunto(s)
Genes , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Proteínas de Plantas/genética , Saccharomyces cerevisiae/genética , Edulcorantes , Secuencia de Bases , Enzimas de Restricción del ADN , Ensayo de Inmunoadsorción Enzimática , Conformación de Ácido Nucleico , Hibridación de Ácido Nucleico , Operón , Plásmidos
20.
Yeast ; 7(5): 463-73, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1654681

RESUMEN

The methylotrophic yeast Hansenula polymorpha, a host organism for the production of heterologous proteins, has been applied to produce the alpha-galactosidase from the plant Cyamopsis tetragonoloba (guar). The yeast/Escherichia coli shuttle expression vector used is based on the origin of replication of the endogenous 2 microns plasmid of Saccharomyces cerevisiae and the LEU2 gene of S. cerevisiae for selection in H. polymorpha. In the expression vector, the alpha-galactosidase is controlled by the methanol-regulated promoter from the methanol oxidase gene, MOX, of H. polymorpha. The signal sequence of SUC2 (invertase) from the yeast S. cerevisiae, was used to ensure secretion of the alpha-galactosidase enzyme. After transformation and stabilization, the expression vector was stably integrated in the genome. The active alpha-galactosidase enzyme was efficiently secreted (greater than 85%) and after methanol induction, the expression level was 42 mg/l. Amino-terminal sequencing of the purified alpha-galactosidase enzyme synthesized by H. polymorpha showed that the S. cerevisiae invertase signal sequence was correctly processed by H. polymorpha. The secreted alpha-galactosidase was glycosylated and had a sugar content of 9.5%. The specific activity of the alpha-galactosidase produced by H. polymorpha was 38 U mg-1 compared to 100 U mg-1 for the guar alpha-galactosidase. Deglycosylation of the H. polymorpha alpha-galactosidase restored the specific activity completely.


Asunto(s)
Fabaceae/enzimología , Regulación Fúngica de la Expresión Génica , Pichia/genética , Plantas Medicinales , Semillas/enzimología , alfa-Galactosidasa/biosíntesis , Secuencia de Bases , Northern Blotting , Southern Blotting , Western Blotting , Clonación Molecular , Medios de Cultivo , ADN de Hongos/química , Vectores Genéticos , Glicosilación , Datos de Secuencia Molecular , Pichia/enzimología , Plásmidos , Regiones Promotoras Genéticas , ARN de Hongos/química , Mapeo Restrictivo , Transformación Genética , alfa-Galactosidasa/genética
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