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1.
Int J Geriatr Psychiatry ; 32(2): 125-135, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27645289

RESUMEN

BACKGROUND AND OBJECTIVE: Current treatments for Alzheimer's Disease (AD) do not affect the course of the illness and brain stimulation techniques are increasingly promoted as potential therapeutic interventions for AD. This study reviews the effects of electromagnetic field (EMF) exposure versus sham exposure on working memory (WM) performance of healthy human participants. METHOD: Online literature databases and previous systematic reviews were searched for studies of EMF and WM in participants without reported memory problems. Two thousand eight hundred and fifty seven studies were identified, and 10 studies met the inclusion criteria. An assessment of study quality was completed, and separate, random effects meta-analyses were conducted for each of the three WM tasks included: n-back, substitution and digit span forward. RESULTS: No differences were found between participants exposed to active EMF versus sham conditions in any of the three working memory tasks examined. CONCLUSION: Results indicate that EMF does not affect WM during the n-back, substitution and digit-span tasks. Future studies should focus on the possible effects of chronic exposure to EMF in older adults with AD using a battery of comparable WM and attention tasks, before EMF can be seriously considered as a potential modulator of WM in AD. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Campos Electromagnéticos , Memoria a Corto Plazo/fisiología , Enfermedad de Alzheimer/terapia , Atención/fisiología , Humanos
2.
Clin Oncol (R Coll Radiol) ; 31(9): e123-e131, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31147146

RESUMEN

AIMS: Organ preservation, an important goal in the treatment of head and neck squamous cell carcinoma (HNSCC), may include induction chemotherapy and cisplatin with radiation therapy (CRT). To our knowledge, no reports have directly compared the impact of induction chemotherapy with that of CRT on health-related quality of life (HRQOL). MATERIALS AND METHODS: In a phase II trial, we assessed the HRQOL of patients treated with induction chemotherapy followed by CRT. Eligible patients had stage III-IV HNSCC. HRQOL questionnaires were administered at baseline, the end of induction (EOI), the end of CRT (EOCRT) and after CRT. Functional Assessment of Cancer Therapy (FACT version 4) assessed HRQOL. We carried out a comparison of changes in HRQOL from baseline to EOI and from EOI to EOCRT. This trial is registered with ClinicalTrials.gov (NCT01566435). RESULTS: Thirty patients were enrolled in the study. Most HRQOL questionnaires were completed (88%). The mean total FACT scores did not differ from baseline to EOI (general: 83.8 versus 79.1, P = 0.08; head and neck: 109.7 versus 105.8, P = 0.33; Total Outcome Index: 69.7 versus 62.3, P = 0.03; respectively, using P ≤ 0.01 to adjust for multiple simultaneous tests of differences). However, total FACT scores significantly worsened from EOI to EOCRT (79.1 versus 62.3, P = 0.01; 105.8 versus 74.2, P < 0.01; 62.3 versus 34.2, P = 0.01; respectively). Within domains, the head and neck cancer subscale score did not differ from baseline to EOI (median 28.5 versus 27.0, P = 0.69), but significantly worsened from EOI to EOCRT (27.0 versus 9.5, P < 0.01). Swallowing, oral pain and voice quality improved from baseline to EOI, but worsened from EOI to EOCRT. Physical and functional scores worsened from baseline to EOI and from EOI to EOCRT. The emotional well-being score improved from baseline to EOI but worsened from EOI to EOCRT. CONCLUSIONS: Overall, HRQOL did not significantly change from baseline to EOI but dramatically worsened from EOI to EOCRT.


Asunto(s)
Antineoplásicos/uso terapéutico , Quimioradioterapia/métodos , Cisplatino/uso terapéutico , Neoplasias de Cabeza y Cuello/radioterapia , Quimioterapia de Inducción/métodos , Calidad de Vida/psicología , Adulto , Anciano , Antineoplásicos/farmacología , Cisplatino/farmacología , Femenino , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
3.
Radiat Prot Dosimetry ; 130(4): 476-81, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18325931

RESUMEN

External auditing of beam output and energy qualities of four therapeutic X-ray machines were performed in three radiation oncology centres in northeastern Brazil. The output and half-value layers (HVLs) were determined using a parallel-plate ionisation chamber and high-purity aluminium foils, respectively. The obtained values of absorbed dose to water and energy qualities were compared with those obtained by the respective institutions. The impact on the prescribed dose was analysed by determining the half-value depth (D(1/2)). The beam outputs presented percent differences ranging from -13 to +25%. The ratio between the HVL in use by the institution and the measurements obtained in this study ranged from 0.75 to 2.33. Such deviations in HVL result in percent differences in dose at D(1/2) ranging from -52 to +8%. It was concluded that dosimetric quality audit programmes in radiation therapy should be expanded to include dermatological radiation therapy and such audits should include HVL verification.


Asunto(s)
Garantía de la Calidad de Atención de Salud , Control de Calidad , Oncología por Radiación/normas , Aluminio/química , Brasil , Diseño de Equipo , Fantasmas de Imagen , Dosis de Radiación , Oncología por Radiación/métodos , Radiometría/métodos , Radioterapia/métodos , Dosificación Radioterapéutica , Agua/química , Rayos X
4.
Mol Cell Biol ; 2(5): 498-507, 1982 May.
Artículo en Inglés | MEDLINE | ID: mdl-7110138

RESUMEN

Several variants resistant to 1.8 x 10(-4) M DL-methotrexate (MTX) have been isolated from the human cell lines HeLa BU25 and VA2-B by exposing them to progressively increasing concentrations of the drug. A striking variability of phenotype and chromosome constitution was observed among the different variants. All resistant cell lines exhibited a greatly increased dihydrofolic acid reductase (DHFR) activity and DHFR content; however, the DHFR activity levels varied considerably among the variants, ranging between about 35 and 275 times the parental level. In the absence of selective pressure, the increased DHFR activity was unstable, and in all cell lines but one was completely lost over a period ranging in different variants between 25 and 200 days. The MTX-resistant cells lines showed anomalies in their chromosome constitution, which involved the occurrence of a duplicated set of chromosomes in most cells of some of the variants and the presence of double minute chromosomes in all cell lines. An analysis of the correlation of loss of double minute chromosomes and loss of DHFR activity in the absence of MTX has given results consistent with the idea that the double-minute chromosomes contain amplified DHFR genes. However, the most significant finding is that, in contrast to what has been reported in the mouse system, the recognizable double-minute chromosomes varied greatly in number in different variants without any relationship to either the level of DHFR activity or the degree of instability of MTX resistance in the absence of selective pressure. These and other observations point to the occurrence in the human MTX-resistant variants of another set of DHFR genes, representing a varied proportion of the total, which is associated with the regular chromosomes, and which may be unstable in the absence of selective pressure.


Asunto(s)
Aberraciones Cromosómicas , Metotrexato/farmacología , Células Clonales/efectos de los fármacos , Resistencia a Medicamentos , Amplificación de Genes , Genes , Células HeLa , Humanos , Cariotipificación , Fenotipo , Selección Genética , Tetrahidrofolato Deshidrogenasa/genética , Tetrahidrofolato Deshidrogenasa/metabolismo
5.
Phys Med Biol ; 52(11): 2987-99, 2007 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-17505084

RESUMEN

A number of patients with lung cancer receive either palliative or curative high-dose-rate (HDR) endobronchial brachytherapy. Up to a third of patients treated with endobronchial HDR die from hemoptysis. Rather than accept hemoptysis as an expected potential consequence of HDR, we have calculated the radial dose distribution for an Ir-192 HDR source, rigorously examined the dose and prescription points recommended by the American Brachytherapy Society (ABS), and performed a radiobiological-based analysis. The radial dose rate of a commercially available Ir-192 source was calculated with a Monte Carlo simulation. Based on the linear quadratic model, the estimated palliative, curative and blood vessel rupture radii from the center of an Ir-192 source were obtained for the ABS recommendations and a series of customized HDR prescriptions. The estimated radius at risk for blood vessel perforation for the ABS recommendations ranges from 7 to 9 mm. An optimized prescription may in some situations reduce this radius to 4 mm. The estimated blood perforation radius is generally smaller than the palliative radius. Optimized and individualized endobronchial HDR prescriptions are currently feasible based on our current understanding of tumor and normal tissue radiobiology. Individualized prescriptions could minimize complications such as fatal hemoptysis without sacrificing efficacy. Fiducial stents, HDR catheter centering or spacers and the use of CT imaging to better assess the relationship between the catheter and blood vessels promise to be useful strategies for increasing the therapeutic index of this treatment modality. Prospective trials employing treatment optimization algorithms are needed.


Asunto(s)
Braquiterapia/métodos , Radioisótopos de Iridio/farmacología , Radiometría/métodos , Espectrofotometría Infrarroja/métodos , Braquiterapia/instrumentación , Bronquios/metabolismo , Electrones , Humanos , Modelos Estadísticos , Modelos Teóricos , Método de Montecarlo , Fotones , Radioterapia/métodos , Factores de Riesgo , Programas Informáticos , Tomografía Computarizada por Rayos X/métodos
6.
Cancer Res ; 47(9): 2504-7, 1987 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-3567934

RESUMEN

Between March 1970 and December 1978 there were 366 patients with prostatic cancer treated by 125I seed implants and pelvic lymph node dissection. All had a minimum of 5 years follow-up. One hundred thirty-three patients had metastatic prostatic cancer in lymph nodes (Stage D1) at the time of lymph node dissection and seed implantation. Ninety-one of the 133 patients were judged to have sufficient metastatic prostatic cancer in their nodal tissue (greater than 50% replacement with tumor) to justify flow cytometric cellular DNA measurements on the involved paraffin-embedded nodal tissue. Nine patients were excluded due to uninterpretable DNA histograms leaving 82 patients for analysis. Forty-nine patients had aneuploid and 33 had diploid tumors. There was no statistical bias between the aneuploid and diploid groups due to age (P = 0.970, chi 2 test), time between diagnosis and implantation (P = 0.217, chi 2 test), number of positive nodes (P = 0.669, two-sample t test of means), or tumor grade (P = 0.332, chi 2 test). Median survival time of the aneuploid and diploid groups was 5.0 and 8.8 years, respectively (P = 0.0109, log rank test). Cox regression analysis confirmed the effect of aneuploidy versus diploidy on survival by controlling for other potentially confounding variables (age, time from diagnosis to implantation, number of positive nodes, and grade). Grade as a predictor of survival did not approach statistical significance in this series of relatively small size (P = 0.116). Thirty-eight of the 82 patients had moderately differentiated neoplasms. Nineteen of these were aneuploid and 19 diploid. The median survival was 5.8 and 9.1 years, respectively, for these grade-matched aneuploid and diploid groups (P = 0.039, log rank test). We conclude that flow cytometric DNA measurements on archived paraffin-embedded tumor in nodal metastases appear to be a strong predictor of survival for Stage DI prostatic cancer.


Asunto(s)
ADN/análisis , Neoplasias de la Próstata/genética , Aneuploidia , Citometría de Flujo , Humanos , Metástasis Linfática , Masculino , Neoplasias de la Próstata/mortalidad
7.
Phys Med Biol ; 60(13): 5199-209, 2015 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-26083863

RESUMEN

Contouring of targets and normal tissues is one of the largest sources of variability in radiation therapy treatment plans. Contours thus require a time intensive and error-prone quality assurance (QA) evaluation, limitations which also impair the facilitation of adaptive radiotherapy (ART). Here, an automated system for contour QA is developed using historical data (the 'knowledge base'). A pilot study was performed with a knowledge base derived from 9 contours each from 29 head-and-neck treatment plans. Size, shape, relative position, and other clinically-relevant metrics and heuristically derived rules are determined. Metrics are extracted from input patient data and compared against rules determined from the knowledge base; a computer-learning component allows metrics to evolve with more input data, including patient specific data for ART. Nine additional plans containing 42 unique contouring errors were analyzed. 40/42 errors were detected as were 9 false positives. The results of this study imply knowledge-based contour QA could potentially enhance the safety and effectiveness of RT treatment plans as well as increase the efficiency of the treatment planning process, reducing labor and the cost of therapy for patients.


Asunto(s)
Neoplasias de Cabeza y Cuello/radioterapia , Modelos Teóricos , Órganos en Riesgo/efectos de la radiación , Garantía de la Calidad de Atención de Salud/normas , Planificación de la Radioterapia Asistida por Computador/métodos , Anciano , Automatización , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Radioterapia Asistida por Computador
8.
J Histochem Cytochem ; 32(4): 447-51, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6368681

RESUMEN

Herpes simplex virus (HSV) infected cells have been detected in tissue culture and human cell specimens by an immunoenzymatic staining method using the fungal enzyme glucose oxidase. Infected cells from culture or human specimens appear as dark blue, brown, or red, depending on the tetrazolium salt used in the disclosing reaction, with virtually no staining of uninfected cells. The specificity and sensitivity of this method and of the more commonly used immunoperoxidase method are comparable, but the immunoglucose oxidase method avoids the problems of nonspecific staining by the endogenous peroxidase present in mucosecretions and inflammatory cells. Staining time can be reduced up to 40% of that necessary for the unlabeled immunoperoxidase procedure without compromising the quality of staining results.


Asunto(s)
Glucosa Oxidasa , Herpes Simple/metabolismo , Técnicas para Inmunoenzimas , Animales , Complejo Antígeno-Anticuerpo/metabolismo , Línea Celular , Femenino , Glucosa Oxidasa/inmunología , Herpes Genital/diagnóstico , Herpes Genital/metabolismo , Herpes Simple/diagnóstico , Histocitoquímica , Humanos , Masculino , Conejos
9.
Science ; 158(3800): 528, 1967 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-17749091
10.
Oecologia ; 77(1): 56-63, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28312315

RESUMEN

1. The foraging activities of the papilionid butterflies Ornithoptera priamus poseidon and Papilio ulysses, and the solitary bee Amegilla sapiens (Apoidea, Anthophoridae) on the shrub Stachytarpheta mutabilis were studied in highland Papua New Guinea. 2. The insects' activity patterns were analysed at three sites with differing diurnal microclimate variation. O. priamus and A. sapiens foraged in the morning (after a period of basking and wing-whirring) and late afternoon when temperatures were well below daily maxima, whereas P. ulysses showed foraging peaks during the hottest part of the day. 3. Site choice by all 3 species appeared to be determined primarily by temperature, but within the limits imposed by temperature, nectar supplies probably determined which site was visited. 4. P. ulysses showed interspersed foraging and courtship behaviour, and no behavioural switching was observed for this species. At high temperatures, both O. priamus and A. sapiens ceased foraging and showed territorial and courtship behaviour. This behavioural change allowed avoidance of heat stress, and occurred even when nectar supplies were maintained at high levels. 5. Thermal effects on behavioural switching in these insects are compared with related phenomena in other bees and butterflies.

11.
J Child Neurol ; 4(4): 286-90, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2794381

RESUMEN

One hundred seventy-six children treated with carbamazepine for epilepsy were monitored over a 12-month period to determine the effects of carbamazepine on the hematologic system. There were no significant changes within the total population in the mean hematocrit or platelet count. The white blood cell count and total neutrophil count showed declines at 1, 8, and 12 months, but the differences did not achieve statistical significance. There was no correlation between the hematologic parameters and carbamazepine blood level, age or sex, or the presence of other drugs. Pretreatment leukopenia and neutropenia were present in 2.8% and 4.0% of children, respectively. During carbamazepine therapy, 8.0% and 17.0% of the children developed leukopenia and neutropenia, respectively, and it was persistent in 1.7% and 2.8%, respectively. The changes in the white blood cell count could be attributed to the changes in the total neutrophil count.


Asunto(s)
Agranulocitosis/inducido químicamente , Carbamazepina/efectos adversos , Epilepsia/tratamiento farmacológico , Leucopenia/inducido químicamente , Neutropenia/inducido químicamente , Carbamazepina/uso terapéutico , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Recuento de Leucocitos/efectos de los fármacos , Masculino
12.
J Reprod Med ; 31(5 Suppl): 399-409, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3014138

RESUMEN

The BglII N DNA fragment of herpes simplex virus type 2 (HSV 2), which is capable of oncogenically transforming cells in vitro, encodes a 37,800-dalton (38-kd) protein that has been seroepidemiologically associated with uterine cervical carcinoma. Polyclonal monospecific antiserum was produced against electrophoretically purified 38 kd from HSV 2-infected cells and used to identify antigenic and biochemical characteristics of the protein as well as to probe transformed cells for the expression of viral 38 kd. The HSV 2 type specificity of the 38-kd protein, previously shown using anti-HSV 2 serum and monoclonal antibodies, was confirmed using anti-38-kd serum. The 38-kd protein of HSV 2 produced in vivo and in vitro displayed type specificity and showed no evidence of posttranslational processing. The 38-kd protein has a relative isoelectric point of 9.1, is synthesized at a maximum level four hours after infection and appears to be a component of the virion. When 35S-methionine radiolabeled 38 kd was immunoprecipitated by anti-38-kd serum, high-molecular-weight proteins (118-140 kd) were also present. However, if prior to reacting with the anti-38-kd serum the high-molecular-weight proteins were separated from 38 kd with sodium dodecyl sulphate-polyacrylamide gel electrophoresis, the only reaction observed with immunoblot was with 38 kd. Therefore, the observed coprecipitation appears to result from the formation of a complex between the proteins and is not the result of shared antigenic determinants. Cells transformed by inactivated HSV 2 were examined for the expression of the 38-kd protein using immunoenzymatic staining. The viral 38-kd protein was not consistently found, but since the protein is reported to be a component of the viral enzyme complex ribonucleotide reductase, it cannot be excluded from possible HSV 2 transformation.


Asunto(s)
Proteínas de Neoplasias/aislamiento & purificación , Simplexvirus/análisis , Proteínas Virales/aislamiento & purificación , Animales , Transformación Celular Neoplásica , Transformación Celular Viral , Células Cultivadas , Cricetinae , ADN Viral/genética , Humanos , Peso Molecular , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/inmunología , Simplexvirus/genética , Simplexvirus/inmunología , Proteínas Virales/genética , Proteínas Virales/inmunología
13.
Endeavour ; 23(2): 56-9, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10507908

RESUMEN

Herbert Spencer's evolutionary ideas related not just to the biological world but to the universe and everything in it. Human societies were also viewed through his evolutionary lens so that Spencer's evolutionary and political ideas are inextricably entwined. This essay looks at some of Spencer's ideas and attempts to locate them in the social and intellectual context of his youth. It also speculates on the rise and fall of Spencer's reputation.


Asunto(s)
Evolución Biológica , Inglaterra , Historia del Siglo XIX , Historia del Siglo XX , Filosofía/historia , Sociología/historia
14.
J Miss State Med Assoc ; 41(2): 479-83, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10710894

RESUMEN

In February 1994, results of a large placebo-controlled trial of zidovudine (ZDV) use during pregnancy (ACTG 076) showed a dramatic reduction in vertical transmission of HIV. In August 1994, the Public Health Service (PHS) recommended routine ZDV use in HIV infected pregnant women and their neonates for the prevention of vertical transmission. We retrospectively reviewed vertical transmission rates of HIV in Mississippi from 1/1/90 to 8/30/94 before the PHS guidelines were released and from 9/1/94 to 12/31/97 after the PHS guidelines were released. We also reviewed data on ZDV use in HIV infected pregnant women and their neonates from 9/1/94 to 12/31/97. Antenatal, intrapartum and neonatal ZDV use increased from 61%, 59% and 73% respectively to 79%, 77% and 92% respectively. After 9/1/94, vertical transmission rates fell by 44%. Zidovudine use during pregnancy has increased in Mississippi since release of the PHS guidelines resulting in a dramatic decline in vertical transmission rates.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/prevención & control , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Zidovudina/uso terapéutico , Femenino , Infecciones por VIH/transmisión , Humanos , Mississippi , Embarazo
16.
Nurse Educ Today ; 30(1): 37-43, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19560237

RESUMEN

The Department of Nursing and Health Studies at the Manukau Institute of Technology (MIT) in Auckland, New Zealand, decided to involve stakeholders from the health care sector in developing a new curriculum. After implementing the new curriculum, the process was evaluated using a content analysis as qualitative research design. Seven individual interviews and one Focus group interview were conducted with the stakeholders to determine their experiences during the process. Ethical permission was sought from the MIT ethical committee. The analyses of the collected data enabled the researchers to identify six main categories. The categories were: "Existing Programme", "The need to change", "The curriculum development process", "The stakeholders", "Personnel", and "Ethnic minorities". From the collected data, it was clear that a new curriculum was necessary to enable the graduates to meet the health care needs of the New Zealand population, especially after the primary health care policy was introduced in New Zealand. It was also clear that the curriculum development process could be a painful process for all concerned, but a strong leadership could cement a feeling of "collegiality" between stakeholders and teaching staff. The importance of considering the rights of ethnic minorities is clearly stated in the Treaty of Waitangi, safeguarding the rights of the Maori People, and therefore applied rigorously in the development process. In this project, the collaborative process was very successful, and the stakeholders actually expressed feelings of "Ownership" of the curriculum.


Asunto(s)
Actitud del Personal de Salud , Actitud Frente a la Salud , Participación de la Comunidad/métodos , Curriculum , Toma de Decisiones en la Organización , Bachillerato en Enfermería/organización & administración , Participación de la Comunidad/psicología , Competencia Cultural/educación , Docentes de Enfermería/organización & administración , Grupos Focales , Humanos , Grupos Minoritarios/psicología , Evaluación de Necesidades , Nueva Zelanda , Investigación en Educación de Enfermería , Investigación Metodológica en Enfermería , Innovación Organizacional , Desarrollo de Programa/métodos , Investigación Cualitativa , Estudiantes de Enfermería/psicología
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