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1.
Scand J Med Sci Sports ; 28(1): 311-318, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28452146

RESUMEN

While we now appreciate that autonomic dysfunction can impact wheelchair rugby performance, this is currently not being assessed during classification, largely due to lack of a standardized and evidence-based strategy to assess autonomic function. Our aim, therefore, was to establish the optimal autonomic testing protocol that best predicts cardiovascular capacity during competition by comprehensively examining autonomic function in elite wheelchair rugby athletes with cervical SCI and thereby enhance the standardized classification. Twenty-six individuals with cervical SCI (C4-C8; AIS A, B, C) participated in this study during the 2015 Parapan American Games in Toronto, Canada. Clinic autonomic testing included: sympathetic skin responses, baseline hemodynamics, orthostatic challenge test, and cold-pressor tests. Further, we completed standard motor/sensory assessments and obtained each participants' International Wheelchair Rugby Federation classification. These clinic metrics were correlated to in-competition heart rate monitoring obtained during competition. The current study provides novel evidence that the change in systolic blood pressure during an orthostatic challenge test predicts approximately 50% of the in-competition peak heart rate (P<.001). Conversely, International Wheelchair Rugby Federation classification was poorly associated with in-competition peak heart rate (R2 =.204; P<.05). Autonomic testing provides deep insight regarding preserved autonomic control after SCI that is associated with performance in elite wheelchair rugby athletes. As such, incorporating assessments of cardiovascular capacity in classification will help to ensure a level playing field and may obviate the need for practices such as boosting to gain an advantage due to poor cardiovascular control.


Asunto(s)
Rendimiento Atlético/fisiología , Sistema Nervioso Autónomo/fisiología , Sistema Cardiovascular , Fútbol Americano , Silla de Ruedas , Adulto , Atletas , Presión Sanguínea , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad
2.
BJOG ; 123(6): 910-6, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26269220

RESUMEN

OBJECTIVE: To examine the association between nondefect adverse birth outcomes and in utero exposure to zidovudine (ZDV)-containing regimens versus non-ZDV antiretroviral (ARV) regimens. DESIGN: Analysis of prospectively-collected data. SETTING: Global. POPULATION: HIV-infected pregnant women prenatally exposed to antiretrovirals. METHODS: Estimation of prevalence of and risk for nondefect adverse birth outcomes among HIV-infected women. MAIN OUTCOME MEASURES: Prevalence of and risk for nondefect adverse birth outcomes. RESULTS: Among 12 780 singleton birth outcomes with in utero ZDV exposure, 96.1% were live births; 3.9% were spontaneous abortions, induced abortions or stillbirths. Among live births, 16.4% were low birthweight (LBW); 12.3% were premature. Among 1904 outcomes with in utero exposure to non-ZDV ARV regimens, 85.8% were live births; 14.2% were spontaneous abortions, induced abortions or stillbirths. Among live births, 14.1% were LBW; 12.4% were premature. Relative risk comparing exposure to ZDV-containing ARV regimens to non-ZDV ARV regimens for spontaneous abortions was 0.18 (95% confidence interval [95% CI] 0.14-0.22); induced abortions 0.28 (95% CI 0.22-0.36); stillbirths 0.76 (95% CI 0.51-1.12); premature births 1.00 (95% CI 0.87-1.15) and LBW 1.17 (95% CI 1.02-1.33). CONCLUSION: Prevalence of nondefect adverse birth outcomes is lower among outcomes with in utero ZDV exposure versus in utero non-ZDV ARV exposure. The risks for spontaneous and induced abortions were no different for ZDV-containing regimens versus non-ZDV ARV regimens. For premature births and stillbirths, there was no significant difference in risk between the two regimens. The risk of LBW was statistically significantly higher among ZDV-containing regimens versus non-ZDV ARV regimens. TWEETABLE ABSTRACT: ZDV-containing regimens do not increase the risk for nondefect adverse birth outcomes.


Asunto(s)
Aborto Espontáneo/epidemiología , Fármacos Anti-VIH/administración & dosificación , Infecciones por VIH/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Efectos Tardíos de la Exposición Prenatal/epidemiología , Mortinato/epidemiología , Zidovudina/administración & dosificación , Aborto Inducido/estadística & datos numéricos , Adolescente , Adulto , Fármacos Anti-VIH/efectos adversos , Femenino , Humanos , Recién Nacido de Bajo Peso , Nacimiento Vivo , Persona de Mediana Edad , Embarazo , Nacimiento Prematuro/epidemiología , Prevalencia , Sistema de Registros , Factores de Riesgo , Adulto Joven , Zidovudina/efectos adversos
4.
Scand J Med Sci Sports ; 25(4): 476-85, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25175825

RESUMEN

We aimed to determine the relationship between level of injury, completeness of injury, resting as well as exercise hemodynamics, and endurance performance in athletes with spinal cord injury (SCI). Twenty-three elite male paracycling athletes (C3-T8) were assessed for neurological level/completeness of injury, autonomic completeness of injury, resting cardiovascular function, and time to complete a 17.3-km World Championship time-trial test. A subset were also fitted with heart rate (HR) monitors and their cycles were fitted with a global positioning systems device (n = 15). Thoracic SCI exhibited higher seated systolic blood pressure along with superior time-trial performance compared with cervical SCI (all P < 0.01). When further stratified by autonomic completeness of injury, the four athletes with cervical autonomic incomplete SCI exhibited a faster time-trial time and a higher average speed compared with cervical autonomic complete SCI (all P < 0.042). Maximum and average HR also tended to be higher in cervical autonomic incomplete vs autonomic complete. There were no differences in time-trial time, HR, or speed between thoracic autonomic complete vs incomplete SCI. In conclusion, autonomic completeness of injury and the consequent ability of the cardiovascular system to respond to exercise appear to be a critical determinant of endurance performance in elite athletes with cervical SCI.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/fisiopatología , Resistencia Física/fisiología , Traumatismos de la Médula Espinal/fisiopatología , Deportes para Personas con Discapacidad/fisiología , Adulto , Rendimiento Atlético/fisiología , Enfermedades del Sistema Nervioso Autónomo/etiología , Ciclismo/fisiología , Presión Sanguínea , Vértebras Cervicales , Prueba de Esfuerzo , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Traumatismos de la Médula Espinal/clasificación , Traumatismos de la Médula Espinal/complicaciones , Vértebras Torácicas
5.
Knee ; 42: 143-152, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37001331

RESUMEN

BACKGROUND: Needle arthroscopy (NA) is an emerging technique that could streamline pathways, facilitate timely care, and reduce service burden. The primary aim was to assess the practical and economic viability of an outpatient NA service. Secondary aims were to assess the relative costs and benefits compared to a conventional arthroscopy (CA) service. METHODS: This service feasibility study was conducted between 2021-2022 in a high-volume national treatment centre. A NA pathway was established for patients with chronic soft tissue pathology or early degenerative knee disease. The pathway was evaluated in terms of: i) cost; ii) efficiency, and iii) waste production, and an assessment was conducted of the patient-related and service-related effects. RESULTS: The cost of the NA pathway was £1555.20 per patient, compared to £2,351.53 for CA. Time to management was 45 days for NA versus 180 days for CA. The NA pathway involved two hospital attendances, whereas CA required a minimum of three. NA cases produced 1.4 kg of non-recyclable waste compared to 5.0 kg produced by CA. For every two cases managed by NA instead of CA, capacity for one additional obligate-inpatient procedure was created. CONCLUSIONS: The NA pathway offers a technically and economically viable approach for the management of refractory knee symptoms in the context of chronic soft tissue or early degenerative disease. NA placed less demand on hospital resources, produced two-thirds less non-recyclable waste, and is amenable to a one-stop clinic approach. Clinical studies focused on objective and patient-reported outcome measures are required to assess clinical efficacy.


Asunto(s)
Artroscopía , Pacientes Ambulatorios , Humanos , Artroscopía/métodos , Pacientes Internos , Articulación de la Rodilla/cirugía , Rodilla
6.
Knee ; 42: 246-257, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37105012

RESUMEN

BACKGROUND: The aim was to review the literature regarding needle arthroscopy using the Arthrex NanoScope system and evaluate: (1) the diagnostic indications, utility, and efficacy compared to conventional methods, and (2) the therapeutic indications, safety, and reported outcomes. METHODS: Searches of three databases (MEDLINE, Embase and PubMed) were conducted in November 2021 using MeSH terms: 'needle arthroscopy', 'human', 'in office arthroscopy', 'needle arthroscope', 'nanoscopic', 'surgery', 'nanoscope' and 'percutaneous arthroscopy'. The included studies were catalogued, quality-assessed using Methodological Index for Non-Randomised Studies (MINORS), and analysed using the Cochrane data collection templates for randomised control trials (RCT) and non-randomised control trials (non-RCT). The majority of studies were non-numerical and were examined using qualitative analysis. RESULTS: The search yielded 314 studies, 22 of which were included for analysis. MINORS assessment was applicable to four studies. Mean MINORS was 10.7/16 with the most frequent limitations being lack of unbiased endpoint or sample size calculation. The level of evidence ranged from level IV-V. Diagnostic and therapeutic indications were described in relation to the: knee (n = 10); shoulder (n = 6); foot/ankle (n = 3); elbow (n = 2), and miscellaneous (n = 1). CONCLUSIONS: Needle arthroscopy can augment the diagnostic process in patients presenting with musculoskeletal complaints, and may provide benefits in terms of diagnostic accuracy, cost efficiency, timeliness of investigation, and a visually impactful patient-centred consultation. Therapeutic interventions are reported by a small number of pioneer groups who report some benefits over conventional arthroscopy. The available literature remains small and of low quality, and more evidence is needed with regards to patient selection, efficacy, safety, and cost. LEVEL OF EVIDENCE: Level V (based on the weakest study included in the Systematic Review).


Asunto(s)
Artroscopía , Pacientes Ambulatorios , Humanos
7.
Pharm Res ; 29(8): 2035-46, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22422320

RESUMEN

PURPOSE: To determine the extent of lateral spread and stratum corneum (SC) penetration of caffeine (CAF), hydrocortisone (HC) and ibuprofen (IBU) using a novel concentric tape stripping technique. METHOD: Ethanolic solutions of CAF, HC or IBU were applied to the forearm of 8 volunteers. At various time points, 10 successive layers of SC were removed by stripping with tapes perforated into concentric rings and analysed for drug concentration and mass of SC protein. In vitro permeation studies assessed the percutaneous absorption of these compounds across human skin. RESULTS: CAF and IBU showed significant lateral spreading across the SC while HC formed a drug depot at the site of application. Relative to the applied dose, the in vivo recovery of all compounds from the combined 10 strips at 3 mins ranged between 83.0 and 92.9 % and decreased to between 64.5 and 66.9 % at 3 h. IBU recovery further decreased to 47.7 ± 5.6 % at 6 h, correlating with greater in vitro penetration relative to CAF and HC. CONCLUSION: Drug concentration decreased with increased lateral distance from the application site. The lower recovery of IBU in the upper tape strip regions compared to CAF and HC may be a consequence of greater penetration into the SC with time.


Asunto(s)
Analgésicos no Narcóticos/administración & dosificación , Antiinflamatorios/administración & dosificación , Cafeína/administración & dosificación , Estimulantes del Sistema Nervioso Central/administración & dosificación , Sistemas de Liberación de Medicamentos/instrumentación , Epidermis/metabolismo , Hidrocortisona/administración & dosificación , Ibuprofeno/administración & dosificación , Adhesivos/química , Administración Tópica , Adulto , Analgésicos no Narcóticos/farmacocinética , Antiinflamatorios/farmacocinética , Cafeína/farmacocinética , Estimulantes del Sistema Nervioso Central/farmacocinética , Femenino , Humanos , Hidrocortisona/farmacocinética , Ibuprofeno/farmacocinética , Masculino , Absorción Cutánea , Adulto Joven
8.
Respir Physiol Neurobiol ; 293: 103714, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34118435

RESUMEN

We compared cardiopulmonary responses to arm-ergometry in individuals with cervical spinal cord injury (C-SCI) and able-bodied controls. We hypothesized that individuals with C-SCI would have higher respiratory frequency (fb) but lower tidal volume (VT) at a given work rate and dynamically hyperinflate during exercise, whereas able-bodied individuals would not. Participants completed pulmonary function testing, an arm-ergometry test to exhaustion, and a sub-maximal exercise test consisting of four-minute stages at 20, 40, 60, and 80% peak work rate. Able-bodied individuals completed a further sub-maximal test with absolute work rate matched to C-SCI. During work rate matched sub-maximal exercise, C-SCI had smaller VT (main effect p < 0.001) compensated by an increased fb (main effect p = 0.009). C-SCI had increased end-expiratory lung volume at 80% peak work rate vs. rest (p < 0.003), whereas able-bodied did not. In conclusion, during arm-ergometry, individuals with C-SCI exhibit altered ventilatory patterns characterized by reduced VT, higher fb, and dynamic hyperinflation that may contribute to the observed reduced aerobic exercise capacity.


Asunto(s)
Brazo/fisiopatología , Médula Cervical/lesiones , Ejercicio Físico/fisiología , Espiración/fisiología , Frecuencia Respiratoria/fisiología , Traumatismos de la Médula Espinal/fisiopatología , Sistema Nervioso Simpático/fisiopatología , Volumen de Ventilación Pulmonar/fisiología , Adulto , Femenino , Humanos , Masculino
9.
Minerva Med ; 111(5): 443-454, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32955824

RESUMEN

Mutation within the FMS-like tyrosine kinase 3 (FLT3) gene are one of the most frequent genetic alterations in acute myeloid leukemia. A high mutation fraction of FLT3-ITD molecules on the surface of leukemia cells is associated with short remissions and overall adverse outcomes in AML. In this article we summarize the clinical trial data of midostaurin - one of the FLT3 inhibitors. We review its use in various combinations both in relapsed/refractory acute myeloid leukemia as well as in the newly diagnosed patients and recollect the evidence of its use as maintenance therapy post allogenic stem cell transplantation. We enumerate the practical issues faced in the use of midostaurin like antifungal prophylaxis, dosage of concomitant chemotherapy agents as well as available data on sequencing of the FLT3 inhibitors. Lastly, we provide our perspective of the future directions for FLT3 inhibition especially midostaurin, the underlying resistance mechanisms and the need for standardization of the FLT3 tests.


Asunto(s)
Antineoplásicos/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Estaurosporina/análogos & derivados , Tirosina Quinasa 3 Similar a fms/genética , Compuestos de Anilina/uso terapéutico , Antraciclinas/uso terapéutico , Antifúngicos/uso terapéutico , Antineoplásicos/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ensayos Clínicos como Asunto , Citarabina/uso terapéutico , Inhibidores del Citocromo P-450 CYP3A/farmacología , Interacciones Farmacológicas , Equinocandinas/uso terapéutico , Predicción , Trasplante de Células Madre Hematopoyéticas , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Quimioterapia de Mantención , Mutación , Micosis/prevención & control , Inhibidores de Proteínas Quinasas/metabolismo , Pirazinas/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia , Estaurosporina/metabolismo , Estaurosporina/uso terapéutico , Triazoles/uso terapéutico , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores
10.
Science ; 226(4680): 1335-7, 1984 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-6505694

RESUMEN

In neuroblastoma lines in which the N-myc gene is present as a single copy, the expression of N-myc as messenger RNA is increased relative to that in nonneuroblastoma cell lines and tumors. The increase of expression in neuroblastomas with amplified N-myc genes is the result of (i) an increase in the absolute amount of expression of each N-myc gene and (ii) an increase in the copy number of the N-myc gene. A second gene--which is amplified in many of the same lines as N-myc--is expressed to about the same degree in most human cell lines and primary tumors regardless of origin (when normalized to gene copy number). Thus, a change in the regulation of N-myc expression in neuroblastomas and certain other tumors results in greatly increased expression of each N-myc gene copy.


Asunto(s)
Amplificación de Genes , Neuroblastoma/genética , Oncogenes , Línea Celular , Regulación de la Expresión Génica , Humanos , ARN Mensajero/metabolismo
11.
RSC Adv ; 9(12): 6973-6985, 2019 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35518463

RESUMEN

Silver nanoparticles (AgNPs) are widely studied for their broad-spectrum antimicrobial effects, and can be utilised readily in biomaterials, however the cellular safety of specific AgNP formulations should be profiled prior to clinical usage. This study determined the cytotoxic effect of small sized (6 nm) alpha lipoic acid capped-AgNPs on human gingival fibroblasts (HGF), as compared to ionic silver and clinical antiseptics. The metabolic pathway was investigated to determine the cellular effects on HGF cells. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) was established for a range of oral related bacteria. Results showed that cell viability decreased with increasing AgNP concentration, whereas lower concentrations of AgNPs, (≤5 µg ml-1) caused a significant increase in cell proliferation at 24 and 72 hour time points. The cytotoxicity profile of AgNPs exhibited significantly lower concentrations, relative to the dose of clinical efficacy, when compared to clinical antiseptics. Caspase 3/7 was not significantly altered when HGF cells were treated with 0.225 µg ml-1 AgNPs, indicating cell necrosis rather than apoptosis. Quantitative RT2-PCR detected an upregulation of genes associated with oxidative stress and the G2M cell cycle checkpoint at ≤4 hours, but expression levels returned to levels consistent with control cells at 24-96 hours. An MIC range of 2.5-12.5 µg ml-1 (min. Escherichia coli, Streptococcus mutans, S. mitis; max. Staphylococcus aureus) was determined across the bacterial species tested and an MBC range of 5-100 µg ml-1 (min. E. coli, max. S. mutans). The antimicrobial profile was similar to that of AgNO3 which suggested that the antimicrobial effect may be influenced by free Ag+ release. It was concluded that alpha lipoic acid capped AgNPs possess limited cytotoxic activity to HGF cells when compared to clinically utilised oral antiseptics, observed via the cellular recovery after initial AgNP treatment and a lack of cumulative cytotoxic effect, whilst maintaining a broad range antimicrobial effect of the AgNPs.

12.
Child Care Health Dev ; 34(1): 87-97, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18171449

RESUMEN

PURPOSE: The purpose of this study is to examine the validity and structure of the Social Support Network Questionnaire (SSNQ), an interview for identifying the positive and negative aspects of individuals' social networks. METHODS: The sample consisted of 536 pregnant and parenting, African-American and Latina adolescents. Participants were recruited from an alternative school for pregnant and parenting adolescents in a large Midwestern city. RESULTS: Confirmatory Factor Analyses revealed the presence of three factors: perceived availability, satisfaction and social strain. All three factors demonstrated adequate internal consistency. Perceived availability and social strain were uncorrelated, implying that they are distinct dimensions. Social strain was the most consistent predictor of psychological well-being. Further, strain in relationships with the young women's male partners added unique variance to the prediction of both anxiety and depression. CONCLUSIONS: The results of this study suggest that the SSNQ may be a useful tool in assessing both positive and negative aspects of pregnant and parenting adolescent mothers' social support networks.


Asunto(s)
Adaptación Psicológica , Negro o Afroamericano , Hispánicos o Latinos , Madres/psicología , Apoyo Social , Adolescente , Análisis Factorial , Femenino , Humanos , Edad Materna , Grupos Minoritarios , Responsabilidad Parental/psicología , Embarazo , Embarazo en Adolescencia/psicología , Psicometría/métodos , Encuestas y Cuestionarios
13.
Acta Biomater ; 74: 454-463, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29705528

RESUMEN

Adhesion plays a major role in the bonding of dental materials. In this study the adhesion of two glass-ceramic systems (IPS e.max and VITABLOCS) to a zirconia sintered substrate using a glass (for IPS e.max) and resin (VITABLOCS) before and after exposure to ageing for 14 days in distilled water at 37 °C are compared using two interfacial fracture mechanics tests, the 3 point bend Schwickerath (Kosyfaki and Swain, 2014; Schneider and Swain, 2015) and 4 point bend (Charalambides et al., 1989) approaches. Both tests result in stable crack extension from which the strain energy release rate (G, N/m or J/m2) can be determined. In the case of the 3 PB test the Work of Fracture was also determined. In addition, the Schwickerath test enables determination of the critical stress for the onset of cracking to occur, which forms the basis of the ISO (ISO9693-2:2016) adhesion test for porcelain ceramic adhesion to zirconia. For the aged samples there was a significant reduction in the resin-bonded strengths (Schwickerath) and strain energy release rate (both 3 and 4 PB tests), which was not evident for the glass bonded specimens. Critical examination of the force-displacement curves showed that ageing of the resin resulted in a major change in the form of the curves, which may be interpreted in terms of a reduction in the critical stress to initiate cracking and also in the development of an R-curve. The extent of the reduction in strain energy release rate following ageing was greater for the Schwickerath test than the Charalambides test. The results are discussed in terms of; the basic mechanics of these two tests, the deterioration of the resin bonding following moisture exposure and the different dimensions of the specimens. These in-vitro results raise concerns regarding resin bonding to zirconia. STATEMENT OF SIGNIFICANCE: The present study uses a novel approach to investigate the role of ageing or environmental degradation on the adhesive bonding of two dental ceramics to zirconia. This continues to be a major clinical problem but current approaches, till now, have relied upon a myriad of strength based tests to quantify the extent of environmental degradation with time. In this paper we use two fracture mechanics approaches, based upon simple 3 and 4 point bend testing procedures that enable stable debonding crack extension to occur. The paper provides a more critical approach to evaluate the role of environmental degradation of adhesion for dental materials.


Asunto(s)
Cerámica/química , Fracaso de la Restauración Dental , Coronas con Frente Estético , Análisis de Falla de Equipo , Vidrio/química , Circonio/química , Humanos
15.
Dent Mater ; 33(9): 1004-1011, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28662858

RESUMEN

OBJECTIVES: To quantify the adhesion of two bonding approaches of zirconia to more aesthetic glass-ceramic materials using the Schwickerath (ISO 9693-2:2016) three point bend (3PB) [1] test to determine the fracture initiation strength and strain energy release rate associated with stable crack extension with this test and the Charalamabides et al. (1989) [2] four point bend (4PB) test. METHODS: Two glass-ceramic materials (VITABLOCS Triluxe forte, Vita Zahnfabrik, Germany and IPS.emax CAD, Ivoclar Vivadent, Liechtenstein) were bonded to sintered zirconia (VITA InCeram YZ). The former was resin bonded using a dual-cure composite resin (Panavia F 2.0, Kuraray Medical Inc., Osaka, Japan) following etching and silane conditioning, while the IPS.emax CAD was glass bonded (IPS e.max CAD Crystall/Connect) during crystallization of the IPS.emax CAD. Specimens (30) of the appropriate dimensions were fabricated for the Schwickerath 3PB and 4PB tests. Strength values were determined from crack initiation while strain energy release rate values were determined from the minima in the force-displacement curves with the 3PB test (Schneider and Swain, 2015) [3] and for 4PB test from the plateau region of stable crack extension. RESULTS: Strength values for the resin and glass bonded glass ceramics to zirconia were 22.20±6.72MPa and 27.02±3.49MPa respectively. The strain energy release rates for the two methods used were very similar and for the glass bonding, (4PB) 15.14±5.06N/m (or J/m2) and (3PB) 16.83±3.91N/m and resin bonding (4PB) 8.34±1.93N/m and (3PB) 8.44±2.81N/m respectively. The differences in strength and strain energy release rate for the two bonding approaches were statistically significant (p<0.05). SEM observations showed fracture occurred adhesively for the resin bonding and cohesively for the glass bonding. SIGNIFICANCE: The present results indicate 3PB and 4PB tests have very similar values for the strain energy release rate determination. However while strength tests reveal minimal differences between resin and glass bonding, strain energy release rates for the latter are superior for bonding CAD/CAM milled glass-ceramics to zirconia.


Asunto(s)
Recubrimiento Dental Adhesivo , Porcelana Dental , Circonio , Cerámica , Cementos Dentales , Humanos , Ensayo de Materiales , Cementos de Resina , Estrés Mecánico , Propiedades de Superficie
16.
Cancer Res ; 60(13): 3343-7, 2000 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10910035

RESUMEN

Tumor invasion and associated angiogenesis evoke a remodeling of extracellular matrix components. Retroviral vectors bearing auxiliary matrix-targeting motifs (ie., collagen-binding polypeptides) accumulate at sites of newly exposed collagen, thus promoting tumor site-specific gene delivery. In this study, we assessed the antitumor effects of serial portal vein infusions of matrix-targeted vectors bearing a mutant cyclin G1 (dnG1) construct in a nude mouse model of liver metastasis. The size of tumor foci was dramatically reduced in dnG1 vector-treated mice compared with that in control vector- or PBS-treated animals (P = 0.0002). These findings represent a definitive advance in the development of targeted injectable vectors for metastatic cancer.


Asunto(s)
Ciclinas/genética , Neoplasias Hepáticas/secundario , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/terapia , Células 3T3 , Animales , Línea Celular , Ciclina G , Ciclina G1 , Ciclinas/fisiología , Terapia Genética , Vectores Genéticos , Humanos , Infusiones Intravenosas , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/prevención & control , Ratones , Ratones Desnudos , Vena Porta , Retroviridae
17.
J Clin Oncol ; 19(18): 3836-47, 2001 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-11559721

RESUMEN

PURPOSE: Forty-eight patients with high-risk re-sected stage III or IV melanoma were immunized with two tumor antigen epitope peptides derived from gp100(209-217)(210M) (IMDQVPSFV) and tyrosinase(368-376)(370D) (YMDGTMSQV) emulsified with incomplete Freund's adjuvant (IFA). Patients received peptides/IFA with or without interleukin (IL)-12 30 ng/kg to evaluate the toxicities and immune responses in either arm with time to relapse and survival as secondary end points. PATIENTS AND METHODS: Immunizations were administered every 2 weeks for 8 weeks, then every 4 weeks for 12 weeks, and then once 8 weeks later. A leukapheresis to obtain peripheral-blood mononuclear cells for immune analyses was done before and after vaccination. Skin testing with peptides and recall reagents was performed before and after vaccinations. RESULTS: Local pain and granuloma formation, fever, and lethargy of grade 1 or 2 were observed. Transient vaccine-related grade 3-but no grade 4-toxicity was observed. Thirty-four of 40 patients developed a positive skin test response to the gp100 peptide but none to tyrosinase. Immune responses were measured by release of gamma-interferon in an enzyme-linked immunosorbent assay (ELISA) by effector cells in the presence of peptide-pulsed antigen-presenting cells or by an antigen-specific tetramer flow cytometry assay. Thirty-three of 38 patients demonstrated an immune response by ELISA after vaccination, as did 37 of 42 patients by tetramer assay. Twenty-four of 48 patients relapsed with a median follow-up of 20 months, and 10 patients in this high-risk group have died. CONCLUSION: These data suggest a significant proportion of patients with resected melanoma mount an antigen-specific immune response against a peptide vaccine and indicate that IL-12 may increase the immune response and supporting further development of IL-12 as a vaccine adjuvant.


Asunto(s)
Vacunas contra el Cáncer/administración & dosificación , Interleucina-12/uso terapéutico , Lípidos , Melanoma/prevención & control , Neoplasias Cutáneas/prevención & control , Adolescente , Vacunas contra el Cáncer/efectos adversos , Vacunas contra el Cáncer/inmunología , Quimioterapia Adyuvante , Femenino , Adyuvante de Freund , Humanos , Interferón gamma/análisis , Leucaféresis , Masculino , Melanoma/sangre , Melanoma/patología , Melanoma/cirugía , Persona de Mediana Edad , Monocitos/inmunología , Estadificación de Neoplasias , Neoplasias Cutáneas/sangre , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Pruebas Cutáneas , Análisis de Supervivencia , Factores de Tiempo , Vacunación
18.
Clin Cancer Res ; 7(10): 2984-97, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11595686

RESUMEN

PURPOSE: The p53 tumor suppressor gene plays a central role in cell cycle regulation and induction of apoptosis. We analyzed p53 alterations and their impact on response to chemotherapy and clinical outcome in ovarian cancer patients. EXPERIMENTAL DESIGN: One hundred seventy-eight ovarian carcinomas, snap frozen and stored at -80 degrees C, were analyzed for mutations of the p53 gene (exons 2-11) by single-strand conformation polymorphism and DNA sequencing and for p53 overexpression by immunohistochemistry (monoclonal antibody DO7). RESULTS: p53 mutations were found in 56% (99 of 178) of the tumors, and 62% of these were located in evolutionary highly conserved domains of the gene. Time to progression and overall survival were significantly shortened in patients with p53 mutations compared with wild-type p53 (P = 0.029 and P = 0.014) and patients with mutations in highly conserved domains as opposed to nonconserved domains or wild-type p53 (P = 0.010 and P = 0.007). p53 protein overexpression (>10% positively stained nuclei) was found in 62% (110 of 178). Time to progression and overall survival were shorter in cases with p53 overexpression (cutpoint, 10%: P = 0.071 and P = 0.056) but only marginally significant. Resistance to adjuvant cisplatin or carboplatin chemotherapy was significantly more frequent in patients with p53 overexpression (P = 0.001) or p53 missense mutations (P = 0.008) than patients with normal p53. CONCLUSIONS: p53 alterations correlate significantly with resistance to platinum-based chemotherapy, early relapse, and shortened overall survival in ovarian cancer patients in univariate analysis. In multivariable analysis though, p53 was not an independent prognostic factor.


Asunto(s)
Antineoplásicos/uso terapéutico , Cisplatino/uso terapéutico , Neoplasias Ováricas/patología , Proteína p53 Supresora de Tumor/genética , Anciano , Análisis Mutacional de ADN , ADN de Neoplasias/química , ADN de Neoplasias/genética , Progresión de la Enfermedad , Resistencia a Antineoplásicos , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Recién Nacido , Persona de Mediana Edad , Análisis Multivariante , Mutación , Estadificación de Neoplasias , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Polimorfismo Conformacional Retorcido-Simple , Pronóstico , Análisis de Supervivencia , Factores de Tiempo
20.
FEBS Lett ; 230(1-2): 155-8, 1988 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-2832212

RESUMEN

In the sera and synovial fluid of patients with rheumatoid arthritis, part of the IgG fraction is found in an aggregated and fluorescent form. Oxygen-free radicals have been implicated in this denaturation, although the precise radical species responsible is unknown. In this work, oxygen-free radicals generated radiolytically were allowed to attack polyclonal IgG in solution. OH radicals induced aggregation of the monomer and a new fluorescence appeared in the visible region (Ex 360 nm, Em 454 nm). The superoxide radical anion was found to be inert in both these respects, whilst peroxy radicals induced autofluorescence without concomitant aggregation. The results suggest that OH.and/or peroxy radical attack may be an in vivo mechanism for IgG denaturation.


Asunto(s)
Hidróxidos/farmacología , Inmunoglobulina G , Peróxidos/farmacología , Superóxidos/farmacología , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Fluorescencia , Radicales Libres , Rayos gamma , Humanos , Radical Hidroxilo , Sustancias Macromoleculares , Espectrometría de Fluorescencia
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