Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 119
Filtrar
1.
Zhonghua Zhong Liu Za Zhi ; 45(2): 129-137, 2023 Feb 23.
Artículo en Chino | MEDLINE | ID: mdl-36781233

RESUMEN

Objective: To investigate the effect of ubiquitin mutation at position 331 of tumor necrosis factor receptor related factor 6 (TRAF6) on the biological characteristics of colorectal cancer cells and its mechanism. Methods: lentivirus wild type (pCDH-3×FLAG-TRAF6) and mutation (pCDH-3×FLAG-TRAF6-331mut) of TRAF6 gene expression plasmid with green fluorescent protein tag were used to infect colorectal cancer cells SW480 and HCT116, respectively. The infection was observed by fluorescence microscope, and the expressions of TRAF6 and TRAF6-331mut in cells was detected by western blot. Cell counting kit-8 (CCK-8) and plate cloning test were used to detect the proliferation ability of colorectal cancer cells in TRAF6 group and TRAF6-331mut group, cell scratch test to detect cell migration, Transwell chamber test to detect cell migration and invasion, immunoprecipitation to detect the ubiquitination of TRAF6 and TRAF6-331mut with ubiquitinof lysine binding sites K48 and K63. Western blot was used to detect the effects of TRAF6 and TRAF6-331mut over expression on the nuclear factor kappa-B (NF-κB) and mitogen activated protein kinase mitogen-activated protein kinase (MAPK)/activating protein-1(AP-1) signal pathway. Results: The successful infection of colorectal cancer cells was observed under fluorescence microscope. Western blot detection showed that TRAF6 and TRAF6-331mut were successfully expressed in colorectal cancer cells. The results of CCK-8 assay showed that on the fourth day, the absorbance values of HCT116 and SW480 cells in TRAF6-331mut group were 1.89±0.39 and 1.88±0.24 respectively, which were lower than those in TRAF6 group (2.09±0.12 and 2.17±0.45, P=0.036 and P=0.011, respectively). The results of plate colony formation assay showed that the number of clones of HCT116 and SW480 cells in TRAF6-331mut group was 120±14 and 85±14 respectively, which was lower than those in TRAF6 group (190±21 and 125±13, P=0.001 and P=0.002, respectively). The results of cell scratch test showed that after 48 hours, the percentage of wound healing distance of HCT116 and SW480 cells in TRAF6-331mut group was (31±12)% and (33±14)%, respectively, which was lower than those in TRAF6 group [(43±13)% and (43±7)%, P=0.005 and 0.009, respectively]. The results of Transwell migration assay showed that the migration numbers of HCT116 and SW480 cells in TRAF6-331mut group were significantly lower than those in TRAF6 group (P<0.001 and P<0.002, respectively). The results of Transwell invasion assay showed that the number of membrane penetration of HCT116 and SW480 cells in TRAF6-331mut group was significantly lower than those in TRAF6 group (P=0.008 and P=0.009, respectively). The results of immunoprecipitation detection showed that the ubiquitin protein of K48 chain pulled by TRAF6-331mut was lower than that of wild type TRAF6 in 293T cells co-transfected with K48 (0.57±0.19), and the ubiquitin protein of K63 chain pulled down by TRAF6-331mut in 293T cells co-transfected with K63 was lower than that of wild type TRAF6 (0.89±0.08, P<0.001). Western blot assay showed that the protein expression levels of NF-κB, p-NF-κB and p-AP-1 in TRAF6-331mut-HCT116 cells were 0.63±0.08, 0.42±0.08 and 0.60±0.07 respectively, which were lower than those in TRAF6-HCT116 cells (P=0.002, P<0.001 and P<0.001, respectively). The expression level of AP-1 protein in TRAF6-HCT116 cells was 0.89±0.06, compared with that in TRAF6-HCT116 cells. The difference was not statistically significant (P>0.05). The protein expression levels of NF-κB, p-NF-κB and p-AP-1 in TRAF6-331mut-SW480 cells were 0.50±0.06, 0.51±0.04, 0.48±0.02, respectively, which were lower than those in TRAF6-SW480 cells (all P<0.001). There was no significant difference in AP-1 protein expression between TRAF6-331mut-SW480 cells and TRAF6-SW480 cells. Conclusion: The ubiquitin site mutation of TRAF6 gene at 331 may prevent the binding of TRAF6 and ubiquitin lysine sites K48 and K63, and then affect the expressions of proteins related to downstream NF-κB and MAPK/AP-1 signal pathways, and inhibit the proliferation, migration and invasion of colorectal cancer cells.


Asunto(s)
Línea Celular Tumoral , Neoplasias Colorrectales , Factor 6 Asociado a Receptor de TNF , Humanos , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/patología , Lisina/metabolismo , FN-kappa B/metabolismo , Factor 6 Asociado a Receptor de TNF/genética , Factor 6 Asociado a Receptor de TNF/metabolismo , Factor de Transcripción AP-1/metabolismo , Ubiquitina/metabolismo
2.
BMC Chem ; 14(1): 63, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33111062

RESUMEN

Polylactic acid (PLA) is a thermoplastic and biodegradable polyester, largely derived from renewable resources such as corn starch, cassava starch and sugarcane. However, PLA is only soluble in a narrow range of solvents such as tetrahydrofuran, dioxane, chlorinated solvents and heated benzene. The limited choices of solvent for PLA dissolution have imposed significant challenges in the development of specifically engineered PLA nanofibers with electrospinning techniques. Generally, the electrospun polymeric materials have been rendered with unique properties such as high porosity and complex geometry while maintaining its biodegradability and biocompatibility for emerging biomedical applications. In this study, a new anticancer drug delivery system composed of PLA nanofibers with encapsulated paclitaxel was developed by the electrospinning of the respective nanofibers on top of a spin-coated thin film with the same chemical compositions. Our unique approach is meant for promoting strong bonding between PLA-based nanofibers and their respective films in order to improve the prolonged release properties and composite film stability within a fluctuative physiochemical environment during cell culture. PLA/paclitaxel nanofiber supported on respective polymeric films were probed by scanning electronic microscope, Fourier transform infrared spectrometer and water contact measurement for determining their surface morphologies, fibers' diameters, molecular vibrational modes, and wettability, respectively. Moreover, PLA/paclitaxel nanofibers supported on respective spin-coated films at different loadings of paclitaxel were evaluated for their abilities in killing human colorectal carcinoma cells (HCT-116). More importantly, MTT assays showed that regardless of the concentrations of paclitaxel, the growth of HCT-116 was effectively inhibited by the prolonged release of paclitaxel from PLA/paclitaxel nanofibers. An effective prolonged delivery system of paclitaxel based on PLA nanofiber-based film has demonstrated exciting potentials for emerging applications as implantable drug delivery patch in post-surgical cancer eradication.

3.
Transl Psychiatry ; 7(2): e1030, 2017 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-28195570

RESUMEN

Global smartphone penetration has led to unprecedented addictive behaviors. To develop a smartphone use/non-use pattern by mobile application (App) in order to identify problematic smartphone use, a total of 79 college students were monitored by the App for 1 month. The App-generated parameters included the daily use/non-use frequency, the total duration and the daily median of the duration per epoch. We introduced two other parameters, the root mean square of the successive differences (RMSSD) and the Similarity Index, in order to explore the similarity in use and non-use between participants. The non-use frequency, non-use duration and non-use-median parameters were able to significantly predict problematic smartphone use. A lower value for the RMSSD and Similarity Index, which represent a higher use/non-use similarity, were also associated with the problematic smartphone use. The use/non-use similarity is able to predict problematic smartphone use and reach beyond just determining whether a person shows excessive use.


Asunto(s)
Conducta Adictiva , Conducta Compulsiva , Teléfono Inteligente , Estudiantes , Recolección de Datos , Femenino , Humanos , Masculino , Aplicaciones Móviles , Universidades , Adulto Joven
4.
J Microsc ; 265(2): 207-213, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27643398

RESUMEN

Glioblastoma multiforme (GBM-WHO grade IV) is the most common and the most aggressive form of brain tumors in adults with the median survival of 10-12 months. The diagnostic detection of extracellular matrix (ECM) component in the tumour microenvironment is of prognostic value. In this paper, the fibrillar collagen deposition associated with vascular elements in GBM were investigated in the fresh specimens and unstained histological slices by using multiphoton microscopy (MPM) based on two-photon excited fluorescence (TPEF) and second harmonic generation (SHG). Our study revealed the existence of fibrillar collagen deposition in the adventitia of remodelled large blood vessels and in glomeruloid vascular structures in GBM. The degree of fibrillar collagen deposition can be quantitatively evaluated by measuring the adventitial thickness of blood vessels or calculating the ratio of SHG pixel to the whole pixel of glomeruloid vascular structure in MPM images. These results indicated that MPM can not only be employed to perform a retrospective study in unstained histological slices but also has the potential to apply for in vivo brain imaging to understand correlations between malignancy of gliomas and fibrillar collagen deposition.


Asunto(s)
Vasos Sanguíneos/patología , Neoplasias Encefálicas/patología , Colágenos Fibrilares/análisis , Glioblastoma/patología , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Neoplasias Encefálicas/diagnóstico , Glioblastoma/diagnóstico , Humanos , Pronóstico , Estudios Retrospectivos
5.
Biomaterials ; 49: 135-44, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25725562

RESUMEN

Biodegradable poly-lactic acid (PLA)--based composites reinforced unidirectionally with high-strength magnesium alloy wires (MAWs) are fabricated by a heat-compressing process and the mechanical properties and degradation behavior are studied experimentally and theoretically. The composites possess improved strengthening and toughening properties. The bending strength and impact strength of the composites with 40 vol% MAWs are 190 MPa and 150 kJ/m(2), respectively, although PLA has a low viscosity and an average molecular weight of 60,000 g/mol. The mechanical properties of the composites can be further improved by internal structure modification and interface strengthening and a numerical model incorporating the equivalent section method (ESM) is proposed for the bending strength. Micro arc oxidization (MAO) of the MAWs is an effective interfacial strengthening method. The composites exhibit high strength retention during degradation and the PLA in the composite shows a smaller degradation rate than pure PLA. The novel biodegradable composites have large potential in bone fracture fixation under load-bearing conditions.


Asunto(s)
Aleaciones/química , Materiales Biocompatibles/química , Ácido Láctico/química , Magnesio/química , Polímeros/química , Análisis de Elementos Finitos , Oxidación-Reducción , Poliésteres , Temperatura , Factores de Tiempo , Soporte de Peso
6.
Spinal Cord ; 51(5): 401-5, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23229618

RESUMEN

STUDY DESIGN: An observational study. OBJECTIVES: To investigate the factors associated with silent autonomic dysreflexia (AD) during urodynamics (UD) in spinal cord injury (SCI) patients. SETTING: Taichung city, Taiwan, ROC. METHODS: Blood pressure (BP) and symptoms of AD were continuously monitored during UD, and systolic blood pressure (SBP) elevations >20 mmHg was considered an AD reaction. AD patients were divided into a symptomatic group and a silent group (without AD symptoms), and variables (basic demographic data, hemodynamic data and UD parameters) were compared. RESULTS: A total of 42 patients, 21 in symptomatic and 21 in silent AD groups, were analyzed. Symptomatic group had significantly greater diastolic blood pressure (DBP) increment and rates of SBP/DBP changes (change of BP divided by duration) as compared to the silent group (29.5 vs 21.7 mmHg; 4.8 vs 2.3 mmHg min(-1) and 2.8 vs 1.4 mmHg min(-1)) (P<0.05). The cutoff points of these three variables, determined by receiver operating characteristic analysis, are: DBP increment of 21 mmHg and rates of SBP/DBP change of 2.27 and 1.16 mmHg min(-1). Age had a weak negative correlation with DBP change (Pearson's r=-0.377, P=0.048) and the silent group was significantly older than the symptomatic group (49.4 vs 40.1 years, P<0.05). CONCLUSION: Patients with more symptomatic AD tended to have significant DBP elevation and more rapid SBP/DBP increments, and this was negatively correlated with age. Aging decreases AD symptoms and the magnitude of DBP elevation, possibly through the mechanism of decreased baroreceptor sensitivity. BP monitoring during UD and other invasive procedures is strongly recommended, especially for elderly SCI patients.


Asunto(s)
Disreflexia Autónoma/etiología , Presión Sanguínea/fisiología , Traumatismos de la Médula Espinal/complicaciones , Urodinámica/fisiología , Adulto , Factores de Edad , Anciano , Área Bajo la Curva , Disreflexia Autónoma/epidemiología , Disreflexia Autónoma/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Curva ROC , Traumatismos de la Médula Espinal/fisiopatología , Adulto Joven
7.
Oncogene ; 32(18): 2325-34, 2013 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-22689053

RESUMEN

The TRC8 gene, which was previously shown to be disrupted by a 3;8 chromosomal translocation in hereditary kidney cancer, encodes for an endoplasmic reticulum-resident E3 ligase. Studies have shown that TRC8 exhibits a tumor-suppressive effect through its E3-ligase activity. Therefore, the identification of its physiological substrates will provide important insights into the molecular mechanism underlying TRC8-mediated tumor suppression. Here we show that TRC8 targets heme oxygenase-1 (HO-1), an antioxidant enzyme highly expressed in various cancers, for ubiquitination and degradation. Ectopic TRC8 expression suppresses HO-1-induced cancer cell growth and migration/invasion. Conversely, HO-1 depletion reduced the tumorigenic and invasive capacities promoted by TRC8 knockdown. HO-1 downregulation in renal carcinoma cells induces a mitotic delay at G2/M phase by increasing the intracellular reactive oxygen species and the DNA-damage-induced checkpoint activation. These results highlight the tumorigenic role of HO-1 and the importance of TRC8-mediated HO-1 degradation in the control of cancer growth.


Asunto(s)
Hemo-Oxigenasa 1/metabolismo , Receptores de Superficie Celular/metabolismo , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Línea Celular , Movimiento Celular , Puntos de Control de la Fase G2 del Ciclo Celular , Células HeLa , Hemo-Oxigenasa 1/genética , Humanos , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Estrés Oxidativo , Receptores de Superficie Celular/genética , Ubiquitinación
8.
J Cardiovasc Surg (Torino) ; 53(4): 487-94, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22854529

RESUMEN

Complex, long segment lesions of the superficial femoral artery (SFA) are common, occurring in 40% of patients with peripheral vascular disease. In particular, chronic total occlusions (CTOs) continue to pose a challenge in the endovascular management of SFA disease. Several conventional wire and catheter based techniques have been described including subintimal recanalization and retrograde techniques. In addition, advances in endovascular technology have led to the development of a series of new devices aimed specifically at facilitating the crossing of long segment SFA occlusions or establishing re-entry of the true lumen. Here we present an overview of the minimally invasive techniques used to recanalize CTOs of the SFA and the latest specialized devices available for both recanalization and re-entry, as well as a summary of the literature supporting their application.


Asunto(s)
Arteriopatías Oclusivas/terapia , Cateterismo Periférico , Procedimientos Endovasculares , Arteria Femoral , Arteriopatías Oclusivas/diagnóstico por imagen , Cateterismo Periférico/efectos adversos , Cateterismo Periférico/instrumentación , Catéteres , Constricción Patológica , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Diseño de Equipo , Arteria Femoral/diagnóstico por imagen , Humanos , Radiografía , Resultado del Tratamiento
10.
Eur J Vasc Endovasc Surg ; 41(1): 48-53, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21109470

RESUMEN

OBJECTIVES: To investigate the outcomes of thoracic endovascular aortic repair (TEVAR) for ruptured descending thoracic aortic aneurysm (rDTAA) in patients older than 75 years. METHODS: We retrospectively identified all patients treated with TEVAR for rDTAA at seven referral centres between 2002 and 2009. The cohort was stratified according to age ≤75 and >75 years, and the outcomes after TEVAR were compared between both groups. RESULTS: Ninety-two patients were identified of which 73% (n = 67) were ≤75 years, and 27% (n = 25) were older than 75 years. The 30-day mortality was 32.0% in patients older than 75 years, and 13.4% in the remaining patients (p = 0.041). Patients older than 75 years suffered more frequently from postoperative stroke (24.0% vs. 1.5%, p = 0.001) and pulmonary complications (40.0% vs. 9.0%, p = 0.001). The aneurysm-related survival after 2 years was 52.1% for patients >75 years, and 83.9% for patients ≤75 years (p = 0.006). CONCLUSIONS: Endovascular treatment of rDTAA in patients older than 75 years is associated with an inferior outcome compared with patients younger than 75 years. However, the mortality and morbidity rates in patients above 75 years are still acceptable. These results may indicate that endovascular treatment for patients older than 75 years with rDTAA is worthwhile.


Asunto(s)
Aneurisma de la Aorta Torácica/mortalidad , Aneurisma de la Aorta Torácica/cirugía , Rotura de la Aorta/mortalidad , Rotura de la Aorta/cirugía , Implantación de Prótesis Vascular , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Hemotórax/mortalidad , Humanos , Italia/epidemiología , Tiempo de Internación/estadística & datos numéricos , Masculino , Países Bajos/epidemiología , Complicaciones Posoperatorias/epidemiología , Reoperación , Estudios Retrospectivos , Choque/mortalidad , Accidente Cerebrovascular/epidemiología , Estados Unidos/epidemiología
11.
Aliment Pharmacol Ther ; 33(1): 89-98, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21083591

RESUMEN

BACKGROUND: Gastro-oesophageal reflux disease (GERD) has been associated with reflux laryngitis. AIMS: To investigate the risk factors and the predictors of pharyngeal acid reflux (PAR) in Taiwanese patients with suspected reflux laryngitis. METHODS: With referral from ENT physicians, 104 patients with symptoms and signs suggestive of reflux laryngitis completed a validated symptom questionnaire, an upper endoscopy exam and ambulatory 24-h pH tests with three sensors located at the hypopharynx, proximal and distal oesophagus. Patients with one or more episodes of PAR were considered abnormal. RESULTS: Pharyngeal acid reflux was identified in 17% (18/104) of patients. In multivariate logistic regression analysis, PAR was independently associated with classical reflux symptoms [adjusted odds ratio (aOR) = 3.5, 95% confidence interval (CI): 1.0-12.8], hiatus hernia (aOR = 6.7, 95% CI: 1.5-30.2) and overweight (aOR = 3.4, 95% CI: 1.0-11.0). In predicting PAR, classical reflux symptoms had a sensitivity of 78% and hiatus hernia had a specificity of 95%. With all three factors, the positive predictive value for PAR was 80%. Classical reflux symptoms included heartburn, chest pain, dyspepsia and acid regurgitation. CONCLUSIONS: Classical reflux symptoms, hiatus hernia and overweight are independent risk factors that may predict pharyngeal acid reflux in patients with suspected reflux laryngitis.


Asunto(s)
Reflujo Biliar , Reflujo Gastroesofágico/complicaciones , Hernia Hiatal/complicaciones , Laringitis/complicaciones , Faringe/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Métodos Epidemiológicos , Femenino , Reflujo Gastroesofágico/fisiopatología , Hernia Hiatal/fisiopatología , Humanos , Laringitis/fisiopatología , Masculino , Persona de Mediana Edad , Sobrepeso/complicaciones , Factores de Riesgo , Adulto Joven
12.
J Nanosci Nanotechnol ; 11(12): 11176-80, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22409080

RESUMEN

Surface nanomechanical behavior under nanoindentation of ZrN and ZrCN film on NiTi substrate was studied. The surface hardness and modulus of the films increase initially with larger nanoindentation depths and then reach their maximum values. Afterwards, they diminish gradually and finally reaching plateau values which are the composite modulus and composite hardness derived from the ZrN/ZrCN film and NiTi substrate. They are higher than those of electropolished NiTi SMA due to the properties of ZrN and ZrCN. In comparison, the surface nanomechanical properties of electropolished NiTi exhibit a different change with depths.

13.
Br Poult Sci ; 51(2): 270-7, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20461588

RESUMEN

1. The purpose of this study was to investigate the effects of different sources of dietary non-starch polysaccharides (NSP) on growth performance, development of gastrointestinal tract, and activities of pancreatic enzymes in goslings from 0 to 21 d of age. 2. A total of 100 one-day-old White Roman female goslings were selected and randomly divided into 5 dietary treatment groups. Each group had 4 replicate cages (100 x 60 x 58 cm) of 5 goslings. Goslings in each group were given one of 5 isoenergetic and isonitrogenous semi-purified diets. Experimental diets were designed to contain 90 g/kg of different sources of dietary NSP from maize (control), barley hull, rice bran, wheat bran, or pectin, respectively, and 97.4 g/kg NSP were supplied by soybean meal. 3. The goslings receiving the pectin diet had significantly higher viscosity in intestinal digesta than the other treatment diets. However, the daily feed intake, daily weight gain, and feed conversion ratio of goslings in the pectin group were significantly lower than those given the other diets. 4. The relative weights of proventriculus, gizzard, liver and pancreas, as well as the relative weights and lengths of various intestinal segments in the goslings that received the pectin diet, were significantly higher than those receiving the other diets. The specific activities (SA) of amylase, lipase, trypsin, and chymotrypsin in the pancreatic tissue of goslings in the pectin group were significantly lower than those in the other groups. 5. Goslings given a soluble NSP source (pectin) diet tended to exhibit inhibited growth and decreased activity of pancreatic enzymes. However, compared with maize, the inclusion of insoluble NSP sources from barley hull, rice bran, and wheat bran did not negatively affect growth and also were not significantly different among the treatment diets.


Asunto(s)
Alimentación Animal/análisis , Anseriformes/fisiología , Tracto Gastrointestinal/crecimiento & desarrollo , Páncreas/enzimología , Polisacáridos/farmacología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Femenino , Tracto Gastrointestinal/efectos de los fármacos , Polisacáridos/química
14.
Phys Rev Lett ; 105(15): 157006, 2010 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-21230933

RESUMEN

We measured the momentum dependence of magnetic excitations in the model spin-1/2 2D antiferromagnetic insulator Sr2CuO2Cl2 (SCOC). We identify a single-spin-wave feature and a multimagnon continuum, with different polarization dependences. The spin waves display a large (70 meV) dispersion between the zone-boundary points (π, 0) and (π/2, π/2). Employing an extended t-t'-t''-U one-band Hubbard model, we find significant electronic hopping beyond nearest-neighbor Cu ions, indicative of extended magnetic interactions. The spectral line shape at (π, 0) indicates sizable quantum effects in SCOC and probably more generally in the cuprates.

15.
J Appl Microbiol ; 107(2): 452-64, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19426278

RESUMEN

AIMS: Some Geobacillus species have highly similar 16S rRNA gene sequences, making 16S rDNA sequence analysis-based identification problematic. To overcome this limitation, recA and rpoB sequence analysis was evaluated as an alternative for distinguishing Geobacillus species. METHODS AND RESULTS: The phylogram of 16S rRNA gene sequences inferred from the neighbour-joining method showed that nine clusters of Geobacillus species were characterized with bootstrap values >90%. The recA and rpoB sequences of 10 reference strains in clusters V, VIb and VIc were amplified and sequenced using consensus primers. Alignment of recA sequences in clusters V, VIb and VIc revealed three types of recA genes, consistent with the putative amino acid sequences and in vivo recA splicing analysis. The phylogram constructed from rpoB sequences showed more divergence than that constructed from 16S rRNA gene sequences. CONCLUSIONS: recA and rpoB sequence analysis differentiated closely-related Geobacillus species and provided direct evidence for reclassifying some species dubiously categorized as Geobacilli. Additionally, this study revealed three types of recA genes in the different Geobacillus species. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlights the advantage of recA and rpoB sequence analysis to supplement 16S rRNA gene sequence analysis for efficient and convenient determination of Geobacillus species.


Asunto(s)
Proteínas Bacterianas/genética , Genes Bacterianos , Geobacillus/clasificación , Reacción en Cadena de la Polimerasa/métodos , Cartilla de ADN/genética , ADN Bacteriano/análisis , ARN Polimerasas Dirigidas por ADN/genética , Geobacillus/genética , Geobacillus/aislamiento & purificación , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Rec A Recombinasas/genética , Análisis de Secuencia de ADN
16.
Int Angiol ; 28(2): 132-7, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19367243

RESUMEN

AIM: Endovascular stenting of atherosclerotic lesions has become a common practice and widely accepted treatment strategy in the treatment of arterial occlusive disease. This study examines the clinical outcome of mesenteric stenting and open mesenteric revascularization for chronic mesenteric ischemia (CMI). METHODS: Hospital records and clinical data of all patients undergoing surgical or endovascular interventions for CMI were reviewed during a recent 10-year period. Clinical outcomes were analyzed between the two groups. RESULTS: Endovascular treatment was performed in 48 patients (58 vessels), and open repair was performed in 96 patients (157 vessels) during the study period. The mean age in the endovascular group was greater than the open group (74+/-9 vs 62+/-7 years, P<0.05). There was no difference in comorbidities, symptom duration, or treatment indications between the two groups. Among patients treated with surgical revascularization, operative strategies included bypass grafting (N.=72, 75%); transaortic endarterectomy (N.=19, 20%), or patch angioplasty (N.=5, 5%). In the open group, one-vessel and two-vessel revascularization was performed in 36% and 64% of patients, respectively. In the endovascular cohorts, one-vessel and two-vessel balloon angioplasty and/or stenting were performed in 79% and 21% of patients, respectively. The hospital length of stay was shorter in the endovascular group (3 vs 12 days, P<0.03). There was no difference in 30-day mortality, in-hospital complication, or three-year cumulative survival rate. Cumulative freedom from recurrent symptoms at three years were significantly greater in the open group (66%) compared to the endovascular group (27%, P<0.02). CONCLUSIONS: Endovascular treatment offers a benefit of shorter hospitalization compared to the open revascularization, while both groups had similar morbidity and mortality rates. Patients treated with surgical reconstruction were more likely to experience long-term symptomatic relief compared to endovascular cohorts, possibly due to higher incidence of two-vessel surgical revascularization. Long term durability of endovascular intervention may be improved with two-vessel revascularization.


Asunto(s)
Angioplastia de Balón/instrumentación , Isquemia/terapia , Oclusión Vascular Mesentérica/terapia , Stents , Procedimientos Quirúrgicos Vasculares , Anciano , Anciano de 80 o más Años , Angioplastia de Balón/efectos adversos , Angioplastia de Balón/mortalidad , Distribución de Chi-Cuadrado , Enfermedad Crónica , Femenino , Humanos , Isquemia/etiología , Isquemia/mortalidad , Isquemia/cirugía , Estimación de Kaplan-Meier , Tiempo de Internación , Masculino , Oclusión Vascular Mesentérica/complicaciones , Oclusión Vascular Mesentérica/mortalidad , Oclusión Vascular Mesentérica/cirugía , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Texas , Factores de Tiempo , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos , Procedimientos Quirúrgicos Vasculares/mortalidad
17.
Acta Biomater ; 5(6): 2238-45, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19251496

RESUMEN

A new surface modification protocol encompassing an electropolishing pretreatment (EP) and subsequent photoelectrocatalytic oxidation (PEO) has been developed to improve the surface properties of biomedical nickel titanium (NiTi) shape memory alloy (SMA). Electropolishing is a good way to improve the resistance to localized breakdown of NiTi SMA whereas PEO offers the synergistic effects of advanced oxidation and electrochemical oxidation. Our results indicate that PEO leads to the formation of a sturdy titania film on the EP NiTi substrate. There is an Ni-free zone near the top surface and a graded interface between the titania layer and NiTi substrate, which bodes well for both biocompatibility and mechanical stability. In addition, Ni ion release from the NiTi substrate is suppressed, as confirmed by the 10-week immersion test. The modulus and hardness of the modified NiTi surface increase with larger indentation depths, finally reaching plateau values of about 69 and 3.1GPa, respectively, which are slightly higher than those of the NiTi substrate but much lower than those of a dense amorphous titania film. In comparison, after undergoing only EP, the mechanical properties of NiTi exhibit an inverse change with depth. The deformation mechanism is proposed and discussed. Our results indicate that surface modification by dual EP and PEO can notably suppress Ni ion release and improve the biocompatibility of NiTi SMA while the surface mechanical properties are not compromised, making the treated materials suitable for hard tissue replacements.


Asunto(s)
Materiales Biocompatibles/química , Electroquímica/métodos , Níquel/química , Fotoquímica/métodos , Titanio/química , Aleaciones/química , Catálisis , Fuerza Compresiva , Módulo de Elasticidad , Dureza , Ensayo de Materiales , Oxidación-Reducción , Propiedades de Superficie
18.
J Mater Sci Mater Med ; 20(1): 223-8, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18758918

RESUMEN

A dense titania film is fabricated in situ on NiTi shape memory alloy (SMA) by anodic oxidation in a Na(2)SO(4) electrolyte. The microstructure of the titania film and its influence on the biocompatibility of NiTi SMA are investigated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma mass spectrometry (ICPMS), hemolysis analysis, and platelet adhesion test. The results indicate that the titania film has a Ni-free zone near the surface and can effectively block the release of harmful Ni ions from the NiTi substrate in simulated body fluids. Moreover, the wettability, hemolysis resistance, and thromboresistance of the NiTi sample are improved by this anodic oxidation method.


Asunto(s)
Materiales Biocompatibles/química , Níquel/química , Titanio/química , Animales , Materiales Biocompatibles/toxicidad , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/toxicidad , Hemólisis/efectos de los fármacos , Técnicas In Vitro , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Níquel/toxicidad , Adhesividad Plaquetaria , Conejos , Análisis Espectral , Propiedades de Superficie , Titanio/toxicidad , Rayos X
19.
Eur J Vasc Endovasc Surg ; 37(1): 15-22, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19008129

RESUMEN

OBJECTIVES: To provide insight into the causes and timing of AAA rupture after EVAR. DESIGN: Original data regarding AAA ruptures following EVAR were collected from MEDLINE and EMBASE databases. Data were extracted systematically and patient and procedural characteristics were analyzed. RESULTS: 270 patients with AAA ruptures after EVAR were identified. Causes of rupture included endoleaks (in 160: type IA 57, type IB 31, type II 23, type III 26, type IV 0, endotension 9, unspecified 14), graft migration 41, graft disconnection 11 and infection 6. Most of the described AAA ruptures occurred within 2-3 years after EVAR. Mean initial AAA diameter was relatively large (65 mm). No abnormalities were present in 41 patients during follow-up before rupture. Structural graft failure was described in 96 and a fatal course in 119 patients. CONCLUSIONS: Focus of surveillance on the first 2-3 years after EVAR may possibly reduce the AAA rupture rate, especially in patients with increased risk of early rupture (relatively large initial AAA diameter or presence of endoleak or graft migration). Better stent-graft durability and longevity is required to further reduce the AAA rupture risk after EVAR. Complete prevention will however remain challenging since AAA rupture may occur even if no predisposing abnormalities are present.


Asunto(s)
Aneurisma de la Aorta Abdominal , Rotura de la Aorta/etiología , Implantación de Prótesis Vascular/efectos adversos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Stents
20.
Biomed Mater Eng ; 19(6): 401-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20231792

RESUMEN

Microstructural characteristics and biocompatibility of a Type-B carbonated hydroxyapatite (HA) coating prepared on NiTi SMA by biomimetic deposition were characterized using XRD, SEM, XPS, FTIR and in vitro studies including hemolysis test, MTT cytotoxicity test and fibroblasts cytocompatibility test. It is found CO(3)(2-) groups were present as substitution of PO(4)(3-) anions in HA crystal lattice due to Type-B carbonate. The growth of Type-B carbonated HA coating in SBF containing HCO(3)(-) ions is stable during all periods of biomimetic deposition. The carbonated HA coating has better blood compatibility than the chemically-polished NiTi SMA. There was a good cell adhesion to this HA coating surface and cell proliferation in the vicinity of the coating was better than that for the chemically-polished NiTi SMA. Thus biomimetic deposition of this carbonated HA coating is a promising way to improve the biocompatibility of NiTi SMA for implant applications.


Asunto(s)
Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Durapatita/química , Durapatita/farmacología , Fibroblastos/efectos de los fármacos , Aleaciones/química , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Ensayo de Materiales , Ratones
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA