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1.
Psychooncology ; 22(3): 481-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22331643

RESUMEN

BACKGROUND: Cancer clinical trials (CCTs) are important tools in the development of improved cancer therapies; yet, participation is low. Key psychosocial barriers exist that appear to impact a patient's decision to participate. Little is known about the relationship among knowledge, self-efficacy, preparation, decisional conflict, and patient decisions to take part in CCTs. OBJECTIVE: The purpose of this study was to determine if preparation for consideration of a CCT as a treatment option mediates the relationship between knowledge, self-efficacy, and decisional conflict. We also explored whether lower levels of decisional conflict are associated with greater likelihood of CCT enrollment. METHOD: In a pre-post test intervention study, cancer patients (N = 105) were recruited before their initial consultation with a medical oncologist. A brief educational intervention was provided for all patients. Patient self-report survey responses assessed knowledge, self-efficacy, preparation for clinical trial participation, decisional conflict, and clinical trial participation. RESULTS: Preparation was found to mediate the relationship between self-efficacy and decisional conflict (p = 0.003 for a test of the indirect mediational pathway for the decisional conflict total score). Preparation had a more limited role in mediating the effect of knowledge on decisional conflict. Further, preliminary evidence indicated that reduced decisional conflict was associated with increased clinical trial enrollment (p = 0.049). CONCLUSIONS: When patients feel greater CCT self-efficacy and have more knowledge, they feel more prepared to make a CCT decision. Reduced decisional conflict, in turn, is associated with the decision to enroll in a clinical trial. Our results suggest that preparation for decision-making should be a target of future interventions to improve participation in CCTs.


Asunto(s)
Ensayos Clínicos como Asunto/psicología , Conflicto Psicológico , Toma de Decisiones , Conocimientos, Actitudes y Práctica en Salud , Neoplasias/terapia , Autoeficacia , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/psicología , Educación del Paciente como Asunto/métodos , Selección de Paciente
2.
Mol Psychiatry ; 16(8): 818-25, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21483434

RESUMEN

Positive emotionality (PEM) (personality construct of well-being, achievement/motivation, social and closeness) has been associated with striatal dopamine D2 receptor availability in healthy controls. As striatal D2 receptors modulate activity in orbitofrontal cortex (OFC) and cingulate (brain regions that process natural and drug rewards), we hypothesized that these regions underlie PEM. To test this, we assessed the correlation between baseline brain glucose metabolism (measured with positron emission tomography and [(18)F]fluoro-deoxyglucose) and scores on PEM (obtained from the multidimensional personality questionnaire or MPQ) in healthy controls (n = 47). Statistical parametric mapping (SPM) analyses revealed that PEM was positively correlated (P(c)<0.05, voxel corrected) with metabolism in various cortical regions that included orbitofrontal (Brodman area, BA 11, 47) and cingulate (BA 23, 32) and other frontal (BA 10, 9), parietal (precuneus, BA 40) and temporal (BA 20, 21) regions that overlap with the brain's default mode network (DMN). Correlations with the other two main MPQ personality dimensions (negative emotionality and constraint) were not significant (SPM P(c)<0.05). Our results corroborate an involvement of orbitofrontal and cingulate regions in PEM, which is considered a trait that protects against substance use disorders. As dysfunction of OFC and cingulate is a hallmark of addiction, these findings support a common neural basis underlying protective personality factors and brain dysfunction underlying substance use disorders. In addition, we also uncovered an association between PEM and baseline metabolism in regions from the DMN, which suggests that PEM may relate to global cortical processes that are active during resting conditions (introspection, mind wandering).


Asunto(s)
Mapeo Encefálico/psicología , Emociones/fisiología , Lóbulo Frontal/fisiología , Giro del Cíngulo/fisiología , Vías Nerviosas/fisiología , Adulto , Mapeo Encefálico/métodos , Femenino , Lóbulo Frontal/diagnóstico por imagen , Giro del Cíngulo/diagnóstico por imagen , Humanos , Masculino , Vías Nerviosas/diagnóstico por imagen , Inventario de Personalidad , Cintigrafía
3.
Folia Morphol (Warsz) ; 81(3): 685-693, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34060645

RESUMEN

BACKGROUND: Primary synovial chondromatosis (PSC) is a rare idiopathic pathology characterised by the formation of osseocartilaginous nodules within synovial joints, tendons, or bursae. The mineralisation pattern of PSC nodules is poorly understood and has yet to be investigated using elemental analysis. Mapping this pattern could elucidate the progression of the disease. MATERIALS AND METHODS: Primary synovial chondromatosis nodules discovered during dissection of a formalin fixed donor were analysed. Scanning electron microscopy paired with energy dispersive X-ray spectroscopy (SEM-EDS) was used to quantify calcium and phosphorus levels to distinguish mineralised components from cartilage, indicated by increased carbon and oxygen concentrations. RESULTS: Nine nodules with average dimensions 1.76 cm × 1.25 cm were identified in the semimembranosus bursa. SEM-EDS demonstrated increased calcium phosphate levels in nodular cores, while outer margins contained primarily carbon and oxygen. Quantification of these elements revealed nodular peripheries to contain 68.0% carbon, 30.2% oxygen, 0.8% calcium, and 1.0% phosphate, while cores were comprised of 38.1% carbon, 42.1% oxygen, 14.1% calcium, and 5.7% phosphate. CONCLUSIONS: Nodules were found to have mineralised cores embedded within a cartilaginous matrix. This pattern suggests disease progression is facilitated by endochondral ossification, opening the potential for new therapeutic techniques.


Asunto(s)
Condromatosis Sinovial , Calcio , Carbono , Condromatosis Sinovial/patología , Humanos , Oxígeno , Fosfatos
4.
Aust J Prim Health ; 28(1): 63-68, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34847988

RESUMEN

Preconception care (PCC) entails counselling and interventions to optimise health before pregnancy. Barriers to this service delivery include access and time. Primary healthcare nurses (PHCNs) are uniquely placed to deliver PCC. The aim of this study was to understand PHCNs' knowledge, practice and attitudes to PCC. A cross-sectional study was performed of a convenience sample of PHCNs in Australia who were seeing people of reproductive age. Recruitment was via the Australian Primary Health Care Nurses Association (APNA) electronic communication platforms. The 18-item, online, anonymous survey captured demographics, as well as PCC knowledge, practices and attitudes. Descriptive statistics were used to describe our findings. In all, 152 completed surveys were received. Of all respondents, 74% stated they discuss PCC in their practice, although only 13% do so routinely. Of these, more preconception discussions are held with women than with men. In total, 95% of respondents identified at least one barrier to delivery of PCC, with lack of time and knowledge being the most common. The findings of this study can inform targeted strategies, including education programs and resources, and consideration of incentives to support PHCNs deliver PCC. This study identifies areas for improvement at the individual, organisational and health system levels to enhance the role of PHCNs in PCC.


Asunto(s)
Competencia Clínica , Atención Preconceptiva , Australia , Estudios Transversales , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Embarazo , Atención Primaria de Salud , Encuestas y Cuestionarios
5.
HIV Med ; 10(2): 116-24, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19200175

RESUMEN

BACKGROUND: This phase IIb study explored the antiviral activity and safety of the investigational CC chemokine receptor 5 (CCR5) antagonist aplaviroc (APL) in antiretroviral-naïve patients harbouring R5- or R5X4-tropic virus. METHODS: A total of 191 patients were randomized 2:2:2:1 to one of three APL dosing regimens or to lamivudine (3TC)/zidovudine (ZDV) twice daily (bid), each in combination with lopinavir/ritonavir (LPV/r) 400 mg/100 mg bid. Efficacy, safety and pharmacokinetic parameters were assessed. RESULTS: This study was terminated prematurely because of APL-associated idiosyncratic hepatotoxicity. A total of 141 patients initiated treatment early enough to have been able to complete 12 weeks on treatment [modified intent-to-treat (M-ITT) population]; of these, 133 completed the 12-week treatment phase. The proportion of subjects in the M-ITT population with HIV-1 RNA <400 copies/mL at week 12 was 50, 48, 54 and 75% in the APL 200 mg bid, APL 400 mg bid, APL 800 mg once a day (qd) and 3TC/ZDV arms, respectively. Similar responses were seen in the few subjects harbouring R5X4-tropic virus (n=17). Common clinical adverse events (AEs) were diarrhoea, nausea, fatigue and headache. APL demonstrated nonlinear pharmacokinetics with high interpatient variability. CONCLUSIONS: While target plasma concentrations of APL were achieved, the antiviral activity of APL+LPV/r did not appear to be comparable to that of 3TC/ZDV+LPV/r.


Asunto(s)
Benzoatos/toxicidad , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/uso terapéutico , VIH-1 , Piperazinas/toxicidad , Pirimidinonas/uso terapéutico , Ritonavir/uso terapéutico , Compuestos de Espiro/toxicidad , Adulto , Anciano , Benzoatos/farmacocinética , Dicetopiperazinas , Esquema de Medicación , Quimioterapia Combinada , Femenino , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Inhibidores de la Proteasa del VIH/farmacocinética , VIH-1/inmunología , Humanos , Lopinavir , Masculino , Persona de Mediana Edad , Piperazinas/farmacocinética , Pirimidinonas/farmacocinética , ARN Viral/inmunología , Receptores CCR5/uso terapéutico , Ritonavir/farmacocinética , Compuestos de Espiro/farmacocinética , Adulto Joven
6.
Science ; 180(4091): 1170-1, 1973 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-17743600

RESUMEN

Skylight polarization, which varies with the position of the sun in the sky, influences the contrast of oil on water. Good contrast is most consistently obtained by viewing in azimuth directions toward or away from the sun. Contrast is enhanced by imaging selected polarization components and by taking the difference between orthogonal polarization components.

7.
Appl Opt ; 47(22): 4085-93, 2008 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-18670566

RESUMEN

When lidar pulses travel through a short path that includes a relatively high concentration of aerosols, scattering phenomena can alter the power and temporal properties of the pulses significantly, causing undesirable effects in the received pulse. In many applications the design of the lidar transmitter and receiver must consider adverse environmental aerosol conditions to ensure the desired performance. We present an analytical model of lidar system operation when the optical path includes aerosols for use in support of instrument design, simulations, and system evaluation. The model considers an optical path terminated with a solid object, although it can also be applied, with minor modifications, to cases where the expected backscatter occurs from nonsolid objects. The optical path aerosols are characterized by their attenuation and backscatter coefficients derived by the Mie theory from the concentration and particle size distribution of the aerosol. Other inputs include the lidar system parameters and instrument response function, and the model output is the time-resolved received pulse. The model is demonstrated and experimentally validated with military fog oil smoke for short ranges (several meters). The results are obtained with a lidar system operating at a wavelength of 0.905 microm within and outside the aerosol. The model goodness of fit is evaluated using the statistical coefficient of determination whose value ranged from 0.88 to 0.99 in this study.


Asunto(s)
Aerosoles/análisis , Aerosoles/química , Algoritmos , Artefactos , Rayos Láser , Modelos Teóricos , Radar , Simulación por Computador , Reproducibilidad de los Resultados , Dispersión de Radiación , Sensibilidad y Especificidad
8.
J Clin Invest ; 86(4): 1124-36, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2212003

RESUMEN

Accumulating evidence implicates a central role for synovial T cells in the pathogenesis of rheumatoid arthritis, but the activation pathways that drive proliferation and effector function of these cells are not known. We have recently generated a novel monoclonal antibody against a rheumatoid synovial T cell line that recognizes an antigen termed UM4D4 (CDw60). This antigen is expressed on a minority of peripheral blood T cells, and represents the surface component of a distinct pathway of human T cell activation. The current studies were performed to examine the expression and function of UM4D4 on T cells obtained from synovial fluid and synovial membranes of patients with rheumatoid arthritis and other forms of inflammatory joint disease. The UM4D4 antigen is expressed at high surface density on about three-fourths of synovial fluid T cells and on a small subset of synovial fluid natural killer cells; in synovial tissue it is present on more than 90% of T cells in lymphoid aggregates, and on approximately 50% of T cells in stromal infiltrates In addition, UM4D4 is expressed in synovial tissue on a previously undescribed population of HLA-DR/DP-negative non-T cells with a dendritic morphology. Anti-UM4D4 was co-mitogenic for both RA and non-RA synovial fluid mononuclear cells, and induced IL-2 receptor expression. The UM4D4/CDw60 antigen may represent a functional activation pathway for synovial compartment T cells, which could play an important role in the pathogenesis of inflammatory arthritis.


Asunto(s)
Antígenos CD/análisis , Antígenos de Diferenciación de Linfocitos T/análisis , Artritis Reumatoide/inmunología , Activación de Linfocitos , Líquido Sinovial/inmunología , Linfocitos T/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Antígenos de Diferenciación de Linfocitos T/fisiología , Antígenos de Superficie/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Receptores de Interleucina-2/análisis , Acetato de Tetradecanoilforbol/farmacología
9.
Clin Pharmacol Ther ; 45(5): 487-94, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2541961

RESUMEN

In the mmol/L concentration range, cimetidine and ranitidine suppress superoxide anion generation by isolated intact human neutrophils. However, at normal pharmacologic concentrations in the mumol/L range, even prolonged exposure of neutrophils to these agents has no demonstrable effect on toxic oxygen species synthesis. In vitro inhibition does not involve neutrophil activation-densensitization or neutrophil cytotoxicity and is reversible to a great extent by drug washout. In the examination of possible free-radical scavenging action of these drugs, it was demonstrated that both drugs inhibit superoxide anion production by xanthine oxidase but not by chelated iron. This raises the possibility that these agents may bear structural similarities to oxypyrazolopyrimidines such as allopurinol.


Asunto(s)
Cimetidina/farmacología , Neutrófilos/efectos de los fármacos , Ranitidina/farmacología , Superóxidos/biosíntesis , Relación Dosis-Respuesta a Droga , Radicales Libres , Humanos , Inmunidad Celular/efectos de los fármacos , NADH NADPH Oxidorreductasas/antagonistas & inhibidores , Neutrófilos/inmunología , Neutrófilos/metabolismo , Xantina Oxidasa/antagonistas & inhibidores
10.
Antivir Ther ; 6(2): 89-96, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11491421

RESUMEN

OBJECTIVE: To evaluate the antiretroviral activity and safety of multiple escalating doses of amprenavir administered alone, and in combination with abacavir in HIV-1-infected adults. DESIGN: Sixty-two HIV-1-infected subjects were enrolled in a multicentre, open-label, non-randomized, dose-escalating trial. METHODS: Subjects were assigned to one of six dose groups and received amprenavir 300 mg twice daily, 300 mg three times daily, 900, 1050, or 1,200 mg twice daily for 4 weeks. One dose group received amprenavir 900 mg twice daily in combination with abacavir 300 mg twice daily for 4 weeks. Antiretroviral activity was assessed by measuring changes from baseline in plasma HIV-1 RNA levels and CD4 cell counts. Safety was evaluated by monitoring clinical adverse events and changes in laboratory values. Genotypic and phenotypic analyses were performed using ABI sequencing and the recombinant virus assay, respectively. RESULTS: At week 4, amprenavir monotherapy (900, 1,050, or 1,200 mg twice daily) resulted in marked decreases in plasma HIV-1 RNA levels (1.3-1.6 log10 copies/ml), and substantial increases in CD4 cell counts in the two dose groups who received 1,050 mg twice daily (118 x 10(6) cells/mm3) or 1,200 mg twice daily (114 x 10(6) cells/mm3). Amprenavir/abacavir resulted in median plasma HIV-1 RNA reductions of 1.8 log10 copies/ml, and median CD4 cell count increases of 138 x 10(6) cells/mm3. Amprenavir was reasonably well tolerated with few treatment-limiting adverse events. No known active site mutations associated with amprenavir resistance were selected in any of the dose groups, and no significant phenotypic resistance to amprenavir developed during 4 weeks of therapy. CONCLUSIONS: The antiviral effect of amprenavir monotherapy increased with escalating doses, and all amprenavir doses were reasonably well tolerated over 4 weeks of therapy. Amprenavir/abacavir combination therapy elicited a potent antiviral effect. The three highest doses of amprenavir (900, 1,050 and 1,200 mg twice daily) were selected to design subsequent Phase II and III studies that confirmed the safety profile and efficacy of amprenavir in combination regimens and led to the approval of amprenavir in the USA in 1999.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/administración & dosificación , VIH-1/efectos de los fármacos , Sulfonamidas/administración & dosificación , Administración Oral , Adulto , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/uso terapéutico , Carbamatos , Didesoxinucleósidos/administración & dosificación , Didesoxinucleósidos/efectos adversos , Didesoxinucleósidos/farmacología , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Femenino , Furanos , Genotipo , Infecciones por VIH/sangre , Inhibidores de la Proteasa del VIH/efectos adversos , Inhibidores de la Proteasa del VIH/uso terapéutico , VIH-1/genética , VIH-1/aislamiento & purificación , Humanos , Masculino , Dosis Máxima Tolerada , Fenotipo , Sulfonamidas/efectos adversos , Sulfonamidas/uso terapéutico , Factores de Tiempo , Resultado del Tratamiento
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