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1.
Semin Oncol Nurs ; 39(4): 151441, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37149439

RESUMO

OBJECTIVES: It is unclear how resilience and posttraumatic growth help women with breast cancer face cancer-related symptom distress. This study included both resilience and posttraumatic growth as mediators in a serial multiple mediator model to examine changes in the relationship between symptom distress and quality of life among women with breast cancer. DATA SOURCES: We conducted the descriptive, cross-sectional study in Taiwan. Data were collected using a survey that assessed symptom distress, resilience, posttraumatic growth, and quality of life. A serial multiple mediator model examined one direct and three specific indirect effects of symptom distress on quality of life through resilience and posttraumatic growth. All 91 participants reported the presence of symptom distress and moderate levels of resilience. Quality of life was significantly associated with symptom distress (b = -1.04), resilience (b = 0.18), and posttraumatic growth (b = 0.09). The indirect effect of symptom distress on quality of life through resilience alone was statistically significant (b = -0.23, 95% CI -0.44 to -0.07) and statistically greater than the specific indirect effect through resilience and posttraumatic growth combined (b = -0.21, 95% CI -0.40 to -0.05). CONCLUSION: Resilience plays a unique role in reducing the impact of symptom distress on the quality of life among women with breast cancer. IMPLICATIONS FOR NURSING PRACTICE: Given the importance of resilience to quality of life, oncology nurses can assess the resilience of women with breast cancer and help identify available internal, external, and existential resources to strengthen their resilience.


Assuntos
Neoplasias da Mama , Crescimento Psicológico Pós-Traumático , Humanos , Feminino , Qualidade de Vida , Estudos Transversais , Estresse Psicológico
2.
J Sch Health ; 93(5): 411-419, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36807316

RESUMO

BACKGROUND: Inadequate sleep has been shown to have detrimental effects on academic performance, physical, mental, and emotional health among adolescents. Factors that influence sleep have been identified. However, most literature is currently limited to urban settings. This study sought to identify factors that influence sleep habits among high school students in a semi-rural community. METHODS: Twelve focus groups were conducted in-person with separate groups of students, parents, and school staff in October 2019. Discussions focused on sleep experiences, knowledge, environment, and factors influencing sleep. Data were coded using grounded theory approach. Themes were identified through summative content analysis. RESULTS: Four major themes were identified: (1) inadequate sleep adversely affects academic performance and emotional health; (2) students face a gap in knowledge regarding sleep duration; (3) academic and nonacademic activities compete with sleep needs; and (4) night-time use of technology negatively influences sleep habits. CONCLUSIONS: Our findings suggest that high school students do not get adequate sleep, largely due to the demands of academic and extracurricular activities and the use of electronics at night. These results can guide the development of targeted sleep education and intervention programs.


Assuntos
População Rural , Privação do Sono , Adolescente , Humanos , Georgia , Estudantes/psicologia , Sono
3.
J Hosp Palliat Nurs ; 25(1): E1-E7, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36162099

RESUMO

Quality of life is an important outcome for people with cancer throughout their cancer trajectory. Having a valid and reliable instrument to measure the quality of life is critical. This cross-sectional study examined the psychometric properties of the Taiwanese version of the Hospice Quality of Life Index among patients with advanced cancer in Taiwan. There were 3 phases: (1) translation of the Hospice Quality of Life Index from English to Mandarin, (2) pilot testing among 30 targeted participants, and (3) field testing to examine validity and reliability. The results of confirmatory factor analysis indicated that the original factor structure of the Hospice Quality of Life Index did not fit the data. After 5 items were deleted from the original questionnaire, principal factor extraction with oblique rotation for exploratory factor analysis yielded 3 subscales: Social/Spiritual Well-Being, Psychological Well-Being, and Functional/Physiological Well-Being. For convergent validity, the small to moderate strength of associations showed shared variance with the Memorial Symptom Assessment Scale. The internal consistency was supported by Cronbach α ranging from 0.77 to 0.86. This study shows early evidence that the quality of life of people with advanced cancer can be appropriately assessed by the Taiwanese Hospice Quality of Life Index.


Assuntos
Hospitais para Doentes Terminais , Neoplasias , Humanos , Psicometria , Qualidade de Vida/psicologia , Estudos Transversais , Reprodutibilidade dos Testes , Neoplasias/complicações , Neoplasias/psicologia
4.
J Nurs Meas ; 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38164589

RESUMO

Background and Purpose: Establishing measurement invariance (MI) is important in the questionnaire validation process. This study examined the MI of the Hospice Quality of Life Index-14 (HQLI-14) when comparing hospice patients with lung cancer and those with non-lung cancers. Methods: The HQLI-14 contains 14 items to measure multidimensional concepts of quality of life. A series of confirmatory factor analyses were performed to test configural, metric, and scalar invariance. Results: The MI of the HQLI-14 was supported by increasing equality constraints on item parameters between groups. Although the configural and metric invariances were both supported, one item regarding breathlessness was noninvariant between the groups with lung and nonlung cancers. Conclusions: The HQLI-14 shows early evidence of meeting the requirements for configural, metric, and partial scalar invariance. It may be used to make meaningful comparisons between patients with lung cancer and nonlung cancers.

5.
Clin J Oncol Nurs ; 26(6): 643-650, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36413716

RESUMO

BACKGROUND: Women with newly diagnosed ovarian cancer who receive chemotherapy experience distressing symptoms and reduced quality of life (QOL). Previous study results identifying changes in symptom distress and QOL over time are limited. OBJECTIVES: This study examined the trajectory of symptom distress and QOL among women with newly diagnosed ovarian cancer from before their first chemotherapy appointment to two weeks after completing six cycles of chemotherapy. METHODS: A longitudinal design was used to examine symptom distress and QOL in 36 participants across eight time points. Generalized estimating equation analyses identified how participants' symptom distress and QOL changed over time. FINDINGS: Psychological symptom distress was highest at baseline and then decreased. Physical symptom distress increased at the second chemotherapy cycle. Similar results were found for QOL, with the lowest QOL reported after the fifth cycle.


Assuntos
Neoplasias Ovarianas , Qualidade de Vida , Feminino , Humanos , Carcinoma Epitelial do Ovário , Neoplasias Ovarianas/tratamento farmacológico , Qualidade de Vida/psicologia , Estudos Longitudinais
6.
Malays J Pathol ; 44(2): 253-260, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36043588

RESUMO

INTRODUCTION: Qualitative Pandy test has long been used to indicate raised globulins in the cerebrospinal fluid (CSF). Despite its shortfalls and the availability of quantitative CSF protein assays, Pandy test continues to be performed in clinical laboratories across Malaysia. OBJECTIVES: (1) Compare diagnostic performance of Pandy test to CSF total protein and albumin; (2) Conduct literature review on clinical utility of Pandy test. MATERIALS AND METHODS: This is a retrospective, cross-sectional study involving 890 inpatients of all ages with CSF biochemistry analysed in Hospital Pulau Pinang over a period of 7 months. Patient demographics, clinical diagnosis and CSF total protein, albumin and Pandy results were collected and analysed using Mann-Whitney U test, Spearman rank-order correlation coefficient, Chi Square test and receiver operating characteristic (ROC) curve analysis. RESULTS: CSF total protein, CSF albumin, CSF protein-albumin difference and age showed significantly higher median values in patients with positive Pandy compared to negative Pandy. Significant associations were found between positive Pandy test with clinical diagnosis (Cramers V 0.443, p<0.01), sample haemolysis (Phi 0.326, p<0.01), CSF protein-albumin difference (Spearman 0.727, p<0.001), CSF total protein (Spearman 0.710, p<0.001) and CSF albumin (Spearman 0.662, p<0.01). All three quantified CSF parameters showed comparably good sensitivity and specificity in determining positive Pandy. DISCUSSION AND CONCLUSION: Good correlation with CSF proteins, analytical issues and reagent hazards indicate no added clinical value of Pandy test in the face of quantified CSF total protein and albumin. Abolishing the test saves resources, reduces occupational hazards and shortens turnaround time without compromising diagnosis.


Assuntos
Albuminas , Estudos Transversais , Humanos , Malásia , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
Emerg Infect Dis ; 26(7): 1392-1398, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32568035

RESUMO

Population genetic analysis revealed that Plasmodium knowlesi infections in Malaysian Borneo are caused by 2 divergent parasites associated with long-tailed (cluster 1) and pig-tailed (cluster 2) macaques. Because the transmission ecology is likely to differ for each macaque species, we developed a simple genotyping PCR to efficiently distinguish between and survey the 2 parasite subpopulations. This assay confirmed differences in the relative proportions in areas of Kapit division of Sarawak state, consistent with multilocus microsatellite analyses. Analyses of 1,204 human infections at Kapit Hospital showed that cluster 1 caused approximately two thirds of cases with no significant temporal changes from 2000 to 2018. We observed an apparent increase in overall numbers in the most recent 2 years studied, driven mainly by increased cluster 1 parasite infections. Continued monitoring of the frequency of different parasite subpopulations and correlation with environmental alterations are necessary to determine whether the epidemiology will change substantially.


Assuntos
Plasmodium knowlesi , Bornéu , DNA de Protozoário , Genética Populacional , Malásia/epidemiologia , Plasmodium knowlesi/genética
8.
Osteoporos Int ; 31(3): 465-474, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31897545

RESUMO

This study examined hip fracture hospitalisation trends and predictors of access to rehabilitation for adults aged ≥ 65 years living with and without dementia. The hospitalisation rate was 2.5 times higher for adults living with dementia and adults who lived in aged care were between 4.8 and 9.3 times less likely to receive rehabilitation. INTRODUCTION: To examine hip fracture hospitalisation temporal trends, health outcomes, and predictors of access to in-hospital rehabilitation for older adults living with and without dementia. METHODS: A population-based retrospective cohort study of adults aged ≥ 65 years hospitalised with a hip fracture during 2007-2017 in New South Wales, Australia. RESULTS: Of the 69,370 hip fracture hospitalisations, 27.1% were adults living with dementia. The hip fracture hospitalisation rate was 2.5 times higher for adults living with dementia compared with adults with no dementia (1186.6 vs 492.9 per 100,000 population). The rate declined by 6.1% per year (95%CI - 6.6 to - 5.5) for adults living with dementia and increased by 1.0% per year (95%CI 0.5-1.5) for adults with no dementia. Multivariable associations identified that adults living with dementia who experienced high frailty and increasing age were between 1.6 and 1.8 times less likely to receive in-hospital rehabilitation. Adults who were living in long-term aged care facilities were between 4.8 and 9.3 times less likely to receive in-hospital rehabilitation which varied by the presence of dementia or delirium. CONCLUSION: Consistent criteria should be applied to determine rehabilitation access, and rehabilitation services designed for older adults living with dementia or in aged care are needed. HIGHLIGHTS: • Adults living with dementia were able to make functional gains following hip fracture rehabilitation. • Need to determine consistent criteria to determine access to hip fracture rehabilitation. • Rehabilitation services specifically designed for adults living with dementia or in aged care are needed.


Assuntos
Demência , Fraturas do Quadril , Assistência ao Convalescente , Idoso , Austrália , Estudos de Coortes , Demência/epidemiologia , Feminino , Fraturas do Quadril/epidemiologia , Hospitalização , Hospitais , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Alta do Paciente , Estudos Retrospectivos
9.
J Autism Dev Disord ; 49(12): 4919-4928, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31473948

RESUMO

Knowledge about the quality of care delivered to children with autism spectrum disorders (ASD) in relation to that recommended by clinical practice guidelines (CPGs) is limited. ASD care quality indicators were developed from CPGs and validated by experts, then used to assess the quality of care delivered by general practitioners (GPs) and pediatricians in Australia. Data were retrospectively collected from the medical records of 228 children (≤ 15 years) with ASD for 2012-2013. Overall quality of care was high, but with considerable variation among indicators, and between GPs and pediatricians-e.g., GPs were less likely to complete the assessment care bundle (61%; 95% CI 21-92). Findings highlight potential areas for improvement in the need for standardized criteria for diagnosis.


Assuntos
Transtorno do Espectro Autista/terapia , Medicina Geral/normas , Qualidade da Assistência à Saúde , Austrália , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/epidemiologia , Criança , Pré-Escolar , Feminino , Medicina Geral/estatística & dados numéricos , Humanos , Masculino , Prontuários Médicos/estatística & dados numéricos
10.
Eur Arch Otorhinolaryngol ; 276(7): 2047-2053, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31161362

RESUMO

PURPOSE: Many authors have described clinicopathologic parameters as factors related to cervical lymph node metastasis development in CN0 stage lip cancer. However, predictive factors for occult lymph node metastasis and criteria for elective neck dissection, especially for early tumour, remain undefined. METHODS: A multi-institutional study with 193 consecutive patients with early lip SCC treated from January 1990 to March 2006 was carried out retrospectively to determine factors predicting occult metastasis. RESULTS: The overall late LNM rate was 13% (25/193). In the multivariate logistic regression study, tumour size and pattern of tumour invasion were factors related to the occurrence of late LNM with rates of sensitivity, specifity and accuracy for occult LNM prediction of 50%, 89.5% and 87%, respectively. CONCLUSION: Our results indicate that patients with stage I and II SCC of the lip with tumour size greater than 18 mm and more aggressive pattern of invasion must be considered a high-risk group for LNM and an END should be performed.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Labiais , Esvaziamento Cervical/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Procedimentos Cirúrgicos Eletivos/métodos , Feminino , Humanos , Neoplasias Labiais/diagnóstico , Neoplasias Labiais/patologia , Modelos Logísticos , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Pescoço , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Carga Tumoral
11.
Ann Emerg Med ; 72(5): 591-601, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30172448

RESUMO

STUDY OBJECTIVE: Studies are divided on the short-term association of air pollution with stroke. Singapore is exposed to seasonal transboundary haze. We aim to investigate the association between air pollution and stroke incidence in Singapore. METHODS: We performed a time-stratified case-crossover analysis on all ischemic stroke cases reported to the Singapore Stroke Registry from 2010 to 2015. Exposure on days was compared with control days on which exposure did not occur. Control days were chosen on the same day of the week earlier and later in the same month in the same year. We fitted a conditional Poisson regression model to daily stroke incidence that included Pollutant Standards Index and environmental confounders. The index was categorized according to established classification (0 to 50=good, 51 to 100=moderate, and ≥101=unhealthy). We assessed the relationship between stroke incidence and Pollutant Standards Index in the entire cohort and in predetermined subgroups of individual-level characteristics. RESULTS: There were 29,384 ischemic stroke cases. Moderate and unhealthy Pollutant Standards Index levels showed association with stroke occurrence, with incidence risk ratio 1.10 (95% confidence interval 1.06 to 1.13) and 1.14 (95% confidence interval 1.03 to 1.25), respectively. Subgroup analyses showed generally significant association, except in Indians and nonhypertensive patients. The association was significant in subgroups aged 65 years or older, women, Chinese, nonsmokers and those with history of diabetes, hypertension, and hyperlipidemia. Stratified by age and smoking, the risk diminished in smokers of all ages. Risk remained elevated for 5 days after exposure. CONCLUSION: We found a short-term elevated risk of ischemic stroke after exposure to air pollution. These findings have public health implications for stroke prevention and emergency health services delivery.


Assuntos
Poluição do Ar/análise , Isquemia Encefálica/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Idoso , Poluição do Ar/efeitos adversos , Isquemia Encefálica/induzido quimicamente , Estudos Cross-Over , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Estações do Ano , Singapura/epidemiologia , Acidente Vascular Cerebral/induzido quimicamente
12.
Mucosal Immunol ; 10(6): 1569-1580, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28295020

RESUMO

Regulation of respiratory mucosal immunity by microbial-derived metabolites has been a proposed mechanism that may provide airway protection. Here we examine the effect of oral Lactobacillus johnsonii supplementation on metabolic and immune response dynamics during respiratory syncytial virus (RSV) infection. L. johnsonii supplementation reduced airway T helper type 2 cytokines and dendritic cell (DC) function, increased regulatory T cells, and was associated with a reprogrammed circulating metabolic environment, including docosahexanoic acid (DHA) enrichment. RSV-infected bone marrow-derived DCs (BMDCs) from L. johnsonii-supplemented mice had altered cytokine secretion, reduced expression of co-stimulatory molecules, and modified CD4+ T-cell cytokines. This was replicated upon co-incubation of wild-type BMDCs with either plasma from L. johnsonii-supplemented mice or DHA. Finally, airway transfer of BMDCs from L. johnsonii-supplemented mice or with wild-type derived BMDCs pretreated with plasma from L. johnsonii-supplemented mice reduced airway pathological responses to infection in recipient animals. Thus L. johnsonii supplementation mediates airway mucosal protection via immunomodulatory metabolites and altered immune function.


Assuntos
Células da Medula Óssea/imunologia , Células Dendríticas/imunologia , Lactobacillus johnsonii/imunologia , Infecções por Vírus Respiratório Sincicial/imunologia , Vírus Sinciciais Respiratórios/imunologia , Linfócitos T Reguladores/metabolismo , Células Th2/metabolismo , Animais , Células da Medula Óssea/virologia , Linhagem Celular , Microambiente Celular , Reprogramação Celular , Citocinas/metabolismo , Células Dendríticas/virologia , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/metabolismo , Imunomodulação , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Linfócitos T Reguladores/imunologia , Células Th2/imunologia
13.
Med J Malaysia ; 71(5): 244-249, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-28064289

RESUMO

BACKGROUND: Little is known about the views of faculty members who train medical students concerning open disclosure. OBJECTIVES: The objectives of this study were to determine the views of faculty in a medical school on: 1 what constitutes a medical error and the severity of such an error in relation to medication use or diagnosis; 2 information giving following such an adverse event, based on severity; and 3 acknowledgement of responsibility, remedial action, compensation, disciplinary action, legal action, and reporting to a higher body in relation to such adverse event. METHODS: We adapted and contextualized a questionnaire developed from a previous study. The questionnaire had 4 case vignettes that described 1 clear medication error with lifelong disability; 2 possible diagnostic error with lifelong disability; 3 possible diagnostic error without harm; and 4 clear medication error without harm. We invited all faculty members attached to the medical school at the International Medical University to participate in the study. RESULTS: Seventy faculty members took part. Faculty members viewed a medical error as having taken place depending on how clearly an error had occurred (94% and 73% versus 53% and 27%). They viewed cases as more severe based on the severity of complications (85% and 46% versus 5% and 10%). With increasing severity, they tended to attribute responsibility for the event and the duty to disclose towards more senior clinicians. They were also more agreeable with remedial action, compensation, disciplinary action, and reporting to a higher agency. There was no strong evidence of association between these areas and the demographics of faculty members. CONCLUSIONS: Faculty members are more likely to perceive an error had occurred depending on the clarity of the circumstances. They viewed severity based on the presence of complications. Severity determined how they attributed responsibility, duty to disclose, and other areas related to open disclosure.


Assuntos
Docentes de Medicina , Erros Médicos , Faculdades de Medicina , Revelação da Verdade , Humanos , Pais
14.
Mucosal Immunol ; 8(5): 1131-43, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25669152

RESUMO

The generation of regulatory T (Treg) cells is driven by Foxp3 and is responsible for dampening inflammation and reducing autoimmunity. In this study, the epigenetic regulation of inducible Treg (iTreg) cells was examined and an H3K4 histone methyltransferase, SMYD3 (SET and MYND Domain 3), which regulates the expression of Foxp3 by a TGFß1/Smad3 (transforming growth factor-ß1/Smad3)-dependent mechanism, was identified. Using chromatin immunoprecipitation assays, SMYD3 depletion led to a reduction in H3K4me3 in the promoter region and CNS1 (conserved noncoding DNA sequence) of the foxp3 locus. SMYD3 abrogation affected iTreg cell formation while allowing dysregulated interleukin-17 production. In a mouse model of respiratory syncytial virus (RSV) infection, a model in which iTreg cells have a critical role in regulating lung pathogenesis, SMYD3(-/-) mice demonstrated exacerbation of RSV-induced disease related to enhanced proinflammatory responses and worsened pathogenesis within the lung. Our data highlight a novel activation role for the TGFß-inducible SMYD3 in regulating iTreg cell formation leading to increased severity of virus-related disease.


Assuntos
Epigênese Genética/imunologia , Fatores de Transcrição Forkhead/imunologia , Histona-Lisina N-Metiltransferase/imunologia , Pneumopatias/imunologia , Infecções por Vírus Respiratório Sincicial/imunologia , Vírus Sinciciais Respiratórios/imunologia , Linfócitos T Reguladores/imunologia , Animais , Fatores de Transcrição Forkhead/genética , Histona-Lisina N-Metiltransferase/genética , Histonas/genética , Histonas/imunologia , Interleucina-17/genética , Interleucina-17/imunologia , Pneumopatias/genética , Pneumopatias/patologia , Camundongos , Camundongos Knockout , Infecções por Vírus Respiratório Sincicial/genética , Infecções por Vírus Respiratório Sincicial/patologia , Linfócitos T Reguladores/patologia , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/imunologia
15.
Scanning ; 35(2): 75-87, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22777599

RESUMO

Detection of cracks from stainless steel pipe images is done using contrast stretching technique. The technique is based on an image filter technique through mathematical morphology that can expose the cracks. The cracks are highlighted and noise removal is done efficiently while still retaining the edges. An automated crack detection system with a camera platform has been successfully implemented. We compare crack extraction in terms of quality measures with those of Otsu's threshold technique and the another technique (Iyer and Sinha, 2005). The algorithm shown is able to achieve good results and perform better than these other techniques.

16.
Br J Radiol ; 85(1019): 1499-506, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23091290

RESUMO

OBJECTIVE: We compared and evaluated the differences between two models for treating bilateral breast cancer (BBC): (i) dose-volume-based intensity-modulated radiation treatment (DV plan), and (ii) dose-volume-based intensity-modulated radiotherapy with generalised equivalent uniform dose-based optimisation (DV-gEUD plan). METHODS: The quality and performance of the DV plan and DV-gEUD plan using the Pinnacle(3) system (Philips, Fitchburg, WI) were evaluated and compared in 10 patients with stage T2-T4 BBC. The plans were delivered on a Varian 21EX linear accelerator (Varian Medical Systems, Milpitas, CA) equipped with a Millennium 120 leaf multileaf collimator (Varian Medical Systems). The parameters analysed included the conformity index, homogeneity index, tumour control probability of the planning target volume (PTV), the volumes V(20 Gy) and V(30 Gy) of the organs at risk (OAR, including the heart and lungs), mean dose and the normal tissue complication probability. RESULTS: Both plans met the requirements for the coverage of PTV with similar conformity and homogeneity indices. However, the DV-gEUD plan had the advantage of dose sparing for OAR: the mean doses of the heart and lungs, lung V(20) (Gy), and heart V(30) (Gy) in the DV-gEUD plan were lower than those in the DV plan (p<0.05). CONCLUSIONS: A better result can be obtained by starting with a DV-generated plan and then improving it by adding gEUD-based improvements to reduce the number of iterations and to improve the optimum dose distribution. Advances to knowledge The DV-gEUD plan provided superior dosimetric results for treating BBC in terms of PTV coverage and OAR sparing than the DV plan, without sacrificing the homogeneity of dose distribution in the PTV.


Assuntos
Neoplasias da Mama/radioterapia , Dosagem Radioterapêutica/normas , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Radioterapia Conformacional/normas
17.
J Am Chem Soc ; 134(30): 12358-61, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22793370

RESUMO

Protein microarrays are fabricated from double-stranded DNA (dsDNA) microarrays by a one-step, multiplexed enzymatic synthesis in an on-chip microfluidic format and then employed for antibody biosensing measurements with surface plasmon resonance imaging (SPRI). A microarray of dsDNA elements (denoted as generator elements) that encode either a His-tagged green fluorescent protein (GFP) or a His-tagged luciferase protein is utilized to create multiple copies of mRNA (mRNA) in a surface RNA polymerase reaction; the mRNA transcripts are then translated into proteins by cell-free protein synthesis in a microfluidic format. The His-tagged proteins diffuse to adjacent Cu(II)-NTA microarray elements (denoted as detector elements) and are specifically adsorbed. The net result is the on-chip, cell-free synthesis of a protein microarray that can be used immediately for SPRI protein biosensing. The dual element format greatly reduces any interference from the nonspecific adsorption of enzyme or proteins. SPRI measurements for the detection of the antibodies anti-GFP and antiluciferase were used to verify the formation of the protein microarray. This convenient on-chip protein microarray fabrication method can be implemented for multiplexed SPRI biosensing measurements in both clinical and research applications.


Assuntos
Análise de Sequência com Séries de Oligonucleotídeos/instrumentação , Análise Serial de Proteínas/instrumentação , Biossíntese de Proteínas , Transcrição Gênica , Adsorção , Bacteriófago T7/enzimologia , Cobre/química , DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/genética , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Histidina/análise , Luciferases/análise , Luciferases/genética , Oligopeptídeos/análise , RNA Mensageiro/genética , Ressonância de Plasmônio de Superfície/instrumentação
18.
Clin Oncol (R Coll Radiol) ; 24(3): 196-207, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21752615

RESUMO

AIMS: To compare the performance of volumetric-modulated arc radiotherapy (VMAT) by dual arc with fixed beam intensity-modulated radiotherapies (IMRTs) and single arc VMAT on nasopharyngeal carcinomas (NPC). MATERIALS AND METHODS: Twenty NPC cases were re-planned using the planning system of the Pinnacle(3®)SmartArc (SA) module to compare the performance of the following four techniques: seven-field (7F) and 18-field (18F) fixed beam IMRT, and single (SA(1)) and dual arc VMAT (SA(2)). The plan was delivered on an Elekta Synergy™ Linac equipped with an 80-leaf 1cm multileaf collimator. Three dose levels of planning target volumes (PTVs) with 70/59.4/54.0Gy in 33 fractions were prescribed and delivered as a simultaneous integrated boost. The conformity index and homogeneity index of the PTVs, the comprehensive quality index (CQI), the normal tissue complication probability for the organs at risk (OARs), and the planning time, delivery efficiency and accuracy were analysed. RESULTS: A significantly inferior conformity index at the three dose levels of PTV and homogeneity index of PTV(70) were observed in SA(1) compared with the other techniques. Comparable conformity index and homogeneity index of the PTV were observed among 7F/18F IMRT and SA(2). Based on the CQI of the 11 OARs, the most efficient dose reduction was observed in 18F IMRT followed in order by SA(2), 7F IMRT and SA(1). The planning time was on average 13.2/24.9/40.1/42.8min for 7F/18F IMRT/SA(1)/SA(2), respectively. With regards to the delivery efficiency compared with 7F IMRT, a 51 and 41% reduction in delivery time was achieved by SA(1) and SA(2), respectively. All techniques presented a high quality assurance pass rate (>98%) of the Γ(3mm,3%) criterion. CONCLUSION: In NPC cases, SA(2) gave superior results in terms of PTV coverage and OAR sparing compared with SA(1) and approached the performance achieved by 18F IMRT, but without sacrificing the delivery efficiency.


Assuntos
Neoplasias Nasofaríngeas/radioterapia , Órgãos em Risco/efeitos da radiação , Fótons/uso terapêutico , Garantia da Qualidade dos Cuidados de Saúde , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Adulto , Carcinoma , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Prognóstico , Dosagem Radioterapêutica
19.
Anal Chem ; 84(1): 440-5, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22126812

RESUMO

The techniques of surface plasmon resonance-phase imaging (SPR-PI) and nanoparticle-enhanced SPR-PI have been implemented for the multiplexed bioaffinity detection of proteins and nucleic acids. The SPR-PI experiments utilized a near-infrared 860 nm light emitting diode (LED) light source and a wedge depolarizer to create a phase grating on a four-element single-stranded DNA (ssDNA) microarray; bioaffinity adsorption onto the various microarray elements was detected via multiplexed real time phase shift measurements. In a first set of demonstration experiments, an ssDNA aptamer microarray was used to directly detect thrombin at concentrations down to 100 pM with SPR-PI. Two different ssDNA aptamers were used in these experiments with two different Langmuir adsorption coefficients, K(A1) = 4.4 × 10(8) M(-1) and K(A2) = 1.2 × 10(8) M(-1). At concentrations below 1 nM, the equilibrium phase shifts observed upon thrombin adsorption vary linearly with concentration with a slope that is proportional to the appropriate Langmuir adsorption coefficient. The observed detection limit of 100 pM is approximately 20 times more sensitive than that observed previously with SPRI. In a second set of experiments, two short ssDNA oligonucleotides (38mers) were simultaneously detected at concentrations down to 25 fM using a three-sequence hybridization format that employed 120 nm DNA-modified silica nanoparticles to enhance the SPR-PI signal. In this first demonstration of nanoparticle-enhanced SPR-PI, the adsorbed silica nanoparticles provided a greatly enhanced phase shift upon bioaffinity adsorption due to a large increase in the real component of the interfacial refractive index from the adsorbed nanoparticle. As in the case of SPR-PI, the detection limit of 25 fM for nanoparticle-enhanced SPR-PI is approximately 20 times more sensitive than that observed previously with nanoparticle-enhanced SPRI.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , DNA/análise , Nanopartículas , Ressonância de Plasmônio de Superfície/métodos , Sequência de Bases
20.
Scanning ; 33(4): 233-51, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21611953

RESUMO

To reduce undesirable charging effects in scanning electron microscope images, Rayleigh contrast stretching is developed and employed. First, re-scaling is performed on the input image histograms with Rayleigh algorithm. Then, contrast stretching or contrast adjustment is implemented to improve the images while reducing the contrast charging artifacts. This technique has been compared to some existing histogram equalization (HE) extension techniques: recursive sub-image HE, contrast stretching dynamic HE, multipeak HE and recursive mean separate HE. Other post processing methods, such as wavelet approach, spatial filtering, and exponential contrast stretching, are compared as well. Overall, the proposed method produces better image compensation in reducing charging artifacts.


Assuntos
Celulose/química , Aumento da Imagem/métodos , Microscopia Eletrônica de Varredura/métodos , Algoritmos , Elétrons , Compostos de Epóxi/química , Razão Sinal-Ruído , Eletricidade Estática , Análise de Ondaletas
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