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1.
J Asthma ; 60(12): 2214-2223, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37366607

RESUMO

OBJECTIVE: To assess factors that are associated with asthma prevalence and asthma attacks among children (0-17 years) and adults (18 years and over) in the United States of America. METHODS: The 2019-2021 National Health Interview Survey data were analyzed using multivariable logistic regression models to determine associations between health outcomes (i.e. current asthma and asthma attacks) and demographic and socioeconomic factors. Each health outcome was regressed over each characteristic variable, adjusting for age, sex, and race/ethnicity for adults and sex and race/ethnicity for children. RESULTS: Asthma was more common among children who were male, blacks, parental education less than bachelor's, or had public health insurance, and among adults who had less than a bachelor's degree, do not own a home, or not in the workforce. Persons in families facing difficulty paying medical bills were more likely to have current asthma (children: aPR = 1.62[1.40-1.88]; adults: aPR = 1.67[1.55-1.81]) and asthma attacks (children: aPR = 1.34[1.15-1.56]; adults: aPR = 1.31[1.20-1.43]). Persons with family income <100% federal poverty threshold (FPT) (children: aPR = 1.39[1.17-1.64]; adults: aPR = 1.64[1.50-1.80]) or adults 100-199% FPT (aPR = 1.28[1.19-1.39]) were more likely to have current asthma. Children and adults with family income <100% FPT and adults 100-199% FPT were also more likely to have asthma attacks. Having asthma attacks was common among adults not in the workforce as well (aPR = 1.17[1.07-1.27]). CONCLUSIONS: Asthma affects certain groups disproportionately. The findings of this paper suggesting asthma disparities continue to persist may increase public health programs awareness to better deliver effective and evidence-based interventions.


Assuntos
Asma , Humanos , Criança , Masculino , Adulto , Estados Unidos/epidemiologia , Adolescente , Feminino , Asma/epidemiologia , Etnicidade , Fatores Socioeconômicos , Renda , Pobreza
2.
Prev Chronic Dis ; 20: E79, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37676856

RESUMO

INTRODUCTION: Asthma affects more than 25 million Americans, including 4.2 million children. The burden of asthma disproportionately affects people enrolled in Medicaid, among other disparate groups. Improved availability and accessibility of guidelines-based treatments and services may ensure positive health outcomes for people with asthma. In this article, we provide an update to the American Lung Association's Asthma Guidelines-Based Care Coverage Project (the Project) to determine the extent of asthma care coverage and associated barriers in Medicaid programs for all 50 states, the District of Columbia, and Puerto Rico, and examine improvements in coverage since 2017. METHODS: Findings from the Project, representing coverage from 2016-2017, were first published in Preventing Chronic Disease in 2018. The Project was updated in 2021 to reflect the National Asthma Education and Prevention Program guidelines 2020 Expert Panel Report-3 updates, which were finalized in December 2020. It now tracks coverage for 8 areas of guidelines-based care and 7 barriers to care in Medicaid programs by reviewing publicly available plan documents and engaging with Medicaid programs to review and confirm findings. RESULTS: Results from the Project, which reflect coverage in 2021-2022, show an increase in comprehensive coverage in Medicaid programs over the last 5 years. However, coverage remains inconsistent across programs, and barriers to accessing asthma care still exist. CONCLUSION: Although substantial improvement has been made to coverage, certain gaps and barriers to care must be addressed for patients to fully benefit from guidelines-based care to manage their asthma and improve health outcomes.


Assuntos
Asma , Medicaid , Estados Unidos , Criança , Humanos , Porto Rico , District of Columbia , Asma/terapia , Monitorização Fisiológica
3.
Can Assoc Radiol J ; : 8465371231217155, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38124063

RESUMO

Purpose: In pancreatic adenocarcinoma, the difficult distinction between normal and affected pancreas on CT studies may lead to discordance between the pre-surgical assessment of vessel involvement and intraoperative findings. We hypothesize that a visual aid tool could improve the performance of radiology residents when detecting vascular invasion in pancreatic adenocarcinoma patients. Methods: This study consisted of 94 pancreatic adenocarcinoma patient CTs. The visual aid compared the estimated body fat density of each patient with the densities surrounding the superior mesenteric artery and mapped them onto the CT scan. Four radiology residents annotated the locations of perceived vascular invasion on each scan with the visual aid overlaid on alternating scans. Using 3 expert radiologists as the reference standard, we quantified the area under the receiver operating characteristic curve to determine the performance of the tool. We then used sensitivity, specificity, balanced accuracy ((sensitivity + specificity)/2), and spatial metrics to determine the performance of the residents with and without the tool. Results: The mean area under the curve was 0.80. Radiology residents' sensitivity/specificity/balanced accuracy for predicting vascular invasion were 50%/85%/68% without the tool and 81%/79%/80% with it compared to expert radiologists, and 58%/85%/72% without the tool and 78%/77%/77% with it compared to the surgical pathology. The tool was not found to impact the spatial metrics calculated on the resident annotations of vascular invasion. Conclusion: The improvements provided by the visual aid were predominantly reflected by increased sensitivity and accuracy, indicating the potential of this tool as a learning aid for trainees.

4.
Nurs Outlook ; 70(4): 639-650, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35798582

RESUMO

BACKGROUND: An understanding of nurse well-being remains elusive, particularly in the current toxic health care environment. Therefore, a conceptual definition of nurse well-being is needed. PURPOSE: The purpose of this paper is to report results of a concept analysis of nurse well-being. METHODS: Rodgers' Evolutionary Method of concept analysis was used to examine the attributes, antecedents, consequences, and related concepts of nurse well-being. FINDINGS: Findings revealed varying levels of nurse well-being: individual, organizational and community. Individual attributes included happiness, satisfaction, optimism, compassion, gratitude, forgiveness, and sound body/spirit. Organizational/community attributes included teamwork, sense of mission, pride in work, and social integration. Antecedents reflected commonalities with Maslow's hierarchy of needs, ranging from basic human needs to self-actualization. Consequences included resilience, collegial relationships, continued growth and development, empowerment, purposeful work, and physical/mental health. DISCUSSION: Standardized definitions of individual and organizational/community nurse well-being should guide future research and policy development. Organizations must build capacity for nurses' well-being and explore its connection to patient safety and quality outcomes.


Assuntos
Formação de Conceito , Atenção à Saúde , Humanos
5.
Aging Clin Exp Res ; 33(9): 2461-2469, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33247424

RESUMO

BACKGROUND: Examining handgrip strength (HGS) asymmetry could extend the utility of handgrip dynamometers for screening future falls. AIMS: We sought to determine the associations of HGS asymmetry on future falls in older Americans. METHODS: The analytic sample included 10,446 adults aged at least 65 years from the 2006-2016 waves of the Health and Retirement Study. Falls were self-reported. A handgrip dynamometer measured HGS. The highest HGS on each hand was used for determining HGS asymmetry ratio: (non-dominant HGS/dominant HGS). Those with HGS asymmetry ratio < 1.0 had their ratio inverted to make all HGS asymmetry ratios ≥ 1.0. Participants were categorized into asymmetry groups based on their inverted HGS asymmetry ratio: (1) 0.0-10.0%, (2) 10.1-20.0%, (3) 20.1-30.0%, and (4) > 30.0%. Generalized estimating equations were used for the analyses. RESULTS: Every 0.10 increase in HGS asymmetry ratio was associated with 1.26 (95% confidence interval (CI) 1.07-1.48) greater odds for future falls. Relative to those with HGS asymmetry 0.0-10.0%, participants with HGS asymmetry > 30.0% had 1.15 (CI 1.01-1.33) greater odds for future falls; however, the associations were not significant for those with HGS asymmetry 10.1-20.0% (odds ratio: 1.06; CI 0.98-1.14) and 20.1-30.0% (odds ratio: 1.10; CI 0.99-1.22). Compared to those with HGS asymmetry 0.0-10.0%, participants with HGS asymmetry > 10.0% and > 20.0% had 1.07 (CI 1.01-1.16) and 1.12 (CI 1.02-1.22) greater odds for future falls, respectively. DISCUSSION: Asymmetric HGS, as a possible biomarker of impaired neuromuscular function, may help predict falls. CONCLUSIONS: We recommend that HGS asymmetry be considered in HGS protocols and fall risk assessments.


Assuntos
Força da Mão , Aposentadoria , Idoso , Biomarcadores , Humanos , Razão de Chances , Autorrelato , Estados Unidos
7.
J Appl Clin Med Phys ; 19(2): 249-257, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29479821

RESUMO

PURPOSE: In this work, we propose a new method of calibrating cone beam computed tomography (CBCT) data sets for radiotherapy dose calculation and plan assessment. The motivation for this patient-specific calibration (PSC) method is to develop an efficient, robust, and accurate CBCT calibration process that is less susceptible to deformable image registration (DIR) errors. METHODS: Instead of mapping the CT numbers voxel-by-voxel with traditional DIR calibration methods, the PSC methods generates correlation plots between deformably registered planning CT and CBCT voxel values, for each image slice. A linear calibration curve specific to each slice is then obtained by least-squares fitting, and applied to the CBCT slice's voxel values. This allows each CBCT slice to be corrected using DIR without altering the patient geometry through regional DIR errors. A retrospective study was performed on 15 head-and-neck cancer patients, each having routine CBCTs and a middle-of-treatment re-planning CT (reCT). The original treatment plan was re-calculated on the patient's reCT image set (serving as the gold standard) as well as the image sets produced by voxel-to-voxel DIR, density-overriding, and the new PSC calibration methods. Dose accuracy of each calibration method was compared to the reference reCT data set using common dose-volume metrics and 3D gamma analysis. A phantom study was also performed to assess the accuracy of the DIR and PSC CBCT calibration methods compared with planning CT. RESULTS: Compared with the gold standard using reCT, the average dose metric differences were ≤ 1.1% for all three methods (PSC: -0.3%; DIR: -0.7%; density-override: -1.1%). The average gamma pass rates with thresholds 3%, 3 mm were also similar among the three techniques (PSC: 95.0%; DIR: 96.1%; density-override: 94.4%). CONCLUSIONS: An automated patient-specific calibration method was developed which yielded strong dosimetric agreement with the results obtained using a re-planning CT for head-and-neck patients.


Assuntos
Algoritmos , Tomografia Computadorizada de Feixe Cônico/normas , Neoplasias de Cabeça e Pescoço/radioterapia , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Calibragem , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Prognóstico , Dosagem Radioterapêutica , Estudos Retrospectivos
8.
J Asthma ; 54(10): 1065-1072, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28282217

RESUMO

BACKGROUND: Uncontrolled asthma decreases quality of life and increases health care use. Most people with asthma need daily use of long-term control (LTC) medications for asthma symptoms and to prevent asthma attacks. Ongoing assessment of a person's level of asthma control and medication use is important in determining the effectiveness of current treatment to decrease the frequency and intensity of symptoms and functional limitations. OBJECTIVE: To assess the use of LTC medication among children and adults with current asthma and identify contributing factors for LTC medication use. METHODS: We used the 2006-2010 Behavioral Risk Factor Surveillance System (BRFSS) child and adult Asthma Call-back Survey (ACBS) data to assess the level of asthma control and LTC medication use. Asthma control was classified as well controlled and uncontrolled using guideline-based measures. We used multivariable logistic regression models to identify contributing factors for LTC medication use and having uncontrolled asthma. RESULTS: Among persons with current asthma, 46.0% of children and 41.5% of adults were taking LTC medications and 38.4% of children and 50.0% of adults had uncontrolled asthma. Among children who had uncontrolled asthma (38.4%), 24.1% were taking LTC medications and 14.3% were not taking LTC medications. Among adults who had uncontrolled asthma (50.0%), 26.7% were taking LTC medications and 23.3% were not taking LTC medications. CONCLUSIONS: Using BRFSS ACBS data to assess the level of asthma control and LTC medication use can identify subpopulations of persons with asthma who receive suboptimal treatment, for which better asthma-related medical treatment and management are needed.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Asma/fisiopatologia , Adolescente , Adulto , Idoso , Antiasmáticos/administração & dosagem , Sistema de Vigilância de Fator de Risco Comportamental , Criança , Pré-Escolar , Preparações de Ação Retardada , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Lactente , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Qualidade de Vida , Fatores de Risco , Fatores Socioeconômicos , Adulto Jovem
9.
Br J Cancer ; 115(10): 1179-1185, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27764842

RESUMO

BACKGROUND: To determine the minimum survival benefits that patients, and their clinicians, judged sufficient to make adjuvant chemotherapy (ACT) worthwhile, in addition to pelvic radiotherapy, for women with high risk and advanced stage endometrial cancer. METHODS: Eighty-three participants in the PORTEC-3 trial completed a time trade-off questionnaire before and after adjuvant therapy; 44 of their clinicians completed it once only. The questionnaire used four hypothetical scenarios including baseline survival times without ACT of 5 and 8 years, and baseline survival rates at 5 years without ACT of 50 and 65%. RESULTS: Over 50% of patients judged an extra 1 year of survival time or an extra 5% in survival rate sufficient to make ACT worthwhile. Over 50% of clinicians judged an extra 1 year of survival time, or an extra 10% in survival rate, sufficient to make ACT worthwhile. Compared with patients, clinicians required similar survival time benefits (medians both 1 year, P=0.4), but larger survival rate benefits (medians 8.5% vs 5%, P=0.03), and clinicians' preferences varied less (IQR 0.5-1.5 years vs 0.4-2 years, P=0.0007; 5-10% vs 1-13%, P=0.004). Patients' preferences changed over time for the survival rate scenarios depending on whether they had ACT or not (change in median benefit - 3 months vs 2.5 months respectively, P=0.028). There were no strong predictors of patients' or clinicians' preferences. CONCLUSIONS: Patients and clinicians judged moderate survival benefits sufficient to make ACT worthwhile after pelvic radiotherapy for endometrial cancer. These benefits are larger than those judged sufficient by patients with breast or colon cancers, but similar to those judged sufficient by patients with lung or ovarian cancers.


Assuntos
Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/terapia , Pessoal de Saúde/psicologia , Preferência do Paciente/psicologia , Adulto , Idoso , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Quimioterapia Adjuvante/métodos , Estudos de Coortes , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/mortalidade , Neoplasias do Colo/terapia , Terapia Combinada/métodos , Neoplasias do Endométrio/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Satisfação do Paciente , Radioterapia/métodos , Inquéritos e Questionários , Taxa de Sobrevida
10.
BMC Health Serv Res ; 16(1): 564, 2016 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-27724889

RESUMO

BACKGROUND: Risks prediction models of 30-day all-cause hospital readmissions are multi-factorial. Severity of illness (SOI) and risk of mortality (ROM) categorized by All Patient Refined Diagnosis Related Groups (APR-DRG) seem to predict hospital readmission but lack large sample validation. Effects of risk reduction interventions including providing post-discharge outpatient visits remain uncertain. We aim to determine the accuracy of using SOI and ROM to predict readmission and further investigate the role of outpatient visits in association with hospital readmission. METHODS: Hospital readmission data were reviewed retrospectively from September 2012 through June 2015. Patient demographics and clinical variables including insurance type, homeless status, substance abuse, psychiatric problems, length of stay, SOI, ROM, ICD-10 diagnoses and medications prescribed at discharge, and prescription ratio at discharge (number of medications prescribed divided by number of ICD-10 diagnoses) were analyzed using logistic regression. Relationships among SOI, type of hospital visits, time between hospital visits, and readmissions were also investigated. RESULTS: A total of 6011 readmissions occurred from 55,532 index admissions. The adjusted odds ratios of SOI and ROM predicting readmissions were 1.31 (SOI: 95 % CI 1.25-1.38) and 1.09 (ROM: 95 % CI 1.05-1.14) separately. Ninety percent (5381/6011) of patients were readmitted from the Emergency Department (ED) or Urgent Care Center (UCC). Average time interval from index discharge date to ED/UCC visit was 9 days in both the no readmission and readmission groups (p > 0.05). Similar hospital readmission rates were noted during the first 10 days from index discharge regardless of whether post-index discharge patient clinic visits occurred when time-to-event analysis was performed. CONCLUSIONS: SOI and ROM significantly predict hospital readmission risk in general. Most readmissions occurred among patients presenting for ED/UCC visits after index discharge. Simply providing early post-discharge follow-up clinic visits does not seem to prevent hospital readmissions.


Assuntos
Assistência ao Convalescente , Assistência Ambulatorial/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Adulto , Grupos Diagnósticos Relacionados , Feminino , Pessoas Mal Alojadas , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Análise de Sobrevida
11.
Breast Cancer Res Treat ; 151(2): 365-72, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25929764

RESUMO

Routine treatment of clinically uninvolved internal mammary nodes in breast cancer patients requiring post-mastectomy radiation therapy is controversial. The purpose of this study was to measure the incidental radiation dose to the internal mammary lymph nodes not included in the planning target volume (PTV) in women with breast cancer receiving post-mastectomy radiation therapy. This retrospective protocol utilized CT-based 3D conformal treatment plans. Fifty consecutive patients were included in the analysis: 25 left breast and 25 right breast patients. 3D conformal treatment plans chest wall tangent fields and matched supraclavicular were used. All plans were prescribed to a total dose of 50 Gy in 25 fractions to the chest wall and 46 Gy in 23 fractions to the supraclavicular field. The internal mammary node chain was intentionally not included in the target volume. For purposes of this study, internal mammary vessels were contoured following the Radiation Therapy Oncologist Group atlas with a 7-mm PTV expansion, utilizing original CT simulation images. The internal mammary nodes were contoured in between the first 3 and first 5 intercostal spaces for comparison. Percent volume of internal mammary node PTV receiving 95 % of the prescribed dose (47.5 Gy) with 7-mm expansion and first 5 intercostal spaces for all patients was 25.2 % (range 0.04-97.6 %, standard deviation (SD) 23.5). The mean internal mammary node dose for all patients was 24.98 Gy (range 3.54-55.93 Gy, SD 16). Results of this study suggest the incidental dose to the internal mammary nodes does not achieve clinically significant therapeutic levels in post-mastectomy breast cancer patients treated with standard 3D conformal radiation therapy chest wall irradiation. If risk factors for microscopic involvement are present, internal mammary nodes must be specifically included in target volumes in order to be adequately treated.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Linfonodos/efeitos da radiação , Cuidados Pós-Operatórios , Dosagem Radioterapêutica , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mastectomia , Radiografia , Planejamento da Radioterapia Assistida por Computador , Radioterapia Conformacional/métodos , Estudos Retrospectivos
12.
Acta Oncol ; 54(3): 322-32, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25350526

RESUMO

BACKGROUND: Accurate target volume segmentation is crucial for success in image-guided radiotherapy. However, variability in anatomical segmentation is one of the most significant contributors to uncertainty in radiotherapy treatment planning. This is especially true for lung cancer where target volumes are subject to varying magnitudes of respiratory motion. MATERIAL AND METHODS: This study aims to analyze multiple observer target volume segmentations and subsequent intensity-modulated radiotherapy (IMRT) treatment plans defined by those segmentations against a reference standard for lung cancer patients imaged with four-dimensional computed tomography (4D-CT). Target volume segmentations of 10 patients were performed manually by six physicians, allowing for the calculation of ground truth estimate segmentations via the simultaneous truth and performance level estimation (STAPLE) algorithm. Segmentation variability was assessed in terms of distance- and volume-based metrics. Treatment plans defined by these segmentations were then subject to dosimetric evaluation consisting of both physical and radiobiological analysis of optimized 3D dose distributions. RESULTS: Significant differences were noticed amongst observers in comparison to STAPLE segmentations and this variability directly extended into the treatment planning stages in the context of all dosimetric parameters used in this study. Mean primary tumor control probability (TCP) ranged from (22.6±11.9)% to (33.7±0.6)%, with standard deviation ranging from 0.5% to 11.9%. However, mean normal tissue complication probabilities (NTCP) based on treatment plans for each physician-derived target volume well as the NTCP derived from STAPLE-based treatment plans demonstrated no discernible trends and variability appeared to be patient-specific. This type of variability demonstrated the large-scale impact that target volume segmentation uncertainty can play in IMRT treatment planning. CONCLUSIONS: Significant target volume segmentation and dosimetric variability exists in IMRT treatment planning amongst experts in the presence of a reference standard for 4D-CT-based lung cancer radiotherapy. Future work is needed to mitigate this uncertainty and ensure highly accurate and effective radiotherapy for lung cancer patients.


Assuntos
Algoritmos , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Tomografia Computadorizada Quadridimensional/métodos , Neoplasias Pulmonares/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Movimento , Variações Dependentes do Observador , Órgãos em Risco/diagnóstico por imagem , Radioterapia (Especialidade)/normas , Respiração , Carga Tumoral , Incerteza
13.
Environ Sci Technol ; 49(21): 12897-903, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26414810

RESUMO

Diffusive gradient in thin-film (DGT) passive samplers are frequently used to monitor the concentrations of metals such as mercury and zinc in sediments and other aquatic environments. The application of these samplers generally presumes that they quantify only the dissolved fraction and not particle-bound metal species that are too large to migrate into the sampler. However, metals associated with very small nanoparticles (smaller than the pore size of DGT samplers) can be abundant in certain environments, yet the implications of these nanoparticles for DGT measurements are unclear. The objective of this study was to determine how the performance of the DGT sampler is affected by the presence of nanoparticulate species of Hg and Zn. DGT samplers were exposed to solutions containing known amounts of dissolved Hg(II) and nanoparticulate HgS (or dissolved Zn(II) and nanoparticulate ZnS). The amounts of Hg and Zn accumulated onto the DGT samplers were quantified over hours to days, and the rates of diffusion of the dissolved metal (i.e., the effective diffusion coefficient D) into the sampler's diffusion layer were calculated and compared for solutions containing varying concentrations of nanoparticles. The results suggested that the nanoparticles deposited on the surface of the samplers might have acted as sorbents, slowing the migration of the dissolved species into the samplers. The consequence was that the DGT sampler data underestimated the dissolved metal concentration in the solution. In addition, X-ray absorption spectroscopy was employed to determine the speciation of the Hg accumulated on the sampler binding layer, and the results indicated that HgS nanoparticles did not appear to directly contribute to the DGT measurement. Overall, our findings suggest that the deployment of DGT samplers in settings where nanoparticles are relevant (e.g., sediments) may result in DGT data that incorrectly estimated the dissolved metal concentrations. Models for metal uptake into the sampler may need to be reconsidered.


Assuntos
Monitoramento Ambiental/instrumentação , Mercúrio/análise , Nanopartículas/química , Sulfetos/química , Zinco/análise , Difusão , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Mercúrio/química , Metais/análise , Metais/química , Nanopartículas/análise , Espectroscopia por Absorção de Raios X , Zinco/química
14.
Microsc Microanal ; 21(2): 313-23, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25731613

RESUMO

Chloroplast division requires filamentation temperature-sensitive Z (FtsZ), a tubulin-like GTPase of cyanobacterial endosymbiotic origin. Plants and algae possess two distinct FtsZ protein families, FtsZ1 and FtsZ2 that co-assemble into a ring (Z-ring) at the division site. Z-ring assembly and disassembly and division site positioning is controlled by both positive and negative factors via their specific interactions with FtsZ1 and FtsZ2. Here we present the in planta analysis of Arabidopsis FtsZ1 and FtsZ2 turnover in the context of a native chloroplast division machinery. Fluorescence recovery after photobleaching analysis was conducted using fluorescently tagged FtsZ at wild-type (WT)-like levels. Rapid photobleaching, low signal-to-noise ratio, and phototropic movements of chloroplasts were overcome by (i) using progressive intervals in time-lapse imaging, (ii) analyzing epidermal rather than stromal chloroplasts, and (iii) employing image stack alignment during postprocessing. In plants of WT background, fluorescence recovery half-times averaged 117 and 325 s for FtsZ1 and FtsZ2, respectively. In plants lacking ARC3, the key negative regulator of FtsZ assembly, the turnover was threefold slower. The findings are discussed in the context of previous results conducted in a heterologous system.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Cloroplastos/metabolismo , Arabidopsis/metabolismo , Fluorescência , Genes Reporter , Processamento de Imagem Assistida por Computador , Microscopia de Fluorescência , Coloração e Rotulagem , Fatores de Tempo , Imagem com Lapso de Tempo
15.
Carcinogenesis ; 35(9): 2074-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24858205

RESUMO

Aberrant expression of subgroup k human endogenous retroviruses (HERV-K) has been observed in prostate cancer. This subgroup is unique because it encodes sequences in the human genome containing open reading frames for near intact retroviruses. We hypothesized that HERV-K reactivation could serve as a non-invasive early disease detection marker for prostate cancer. We evaluated HERV-K gag messenger RNA (mRNA) expression in blood samples of African-American and European-American men using a case-control design via quantitative real-time PCR. Additionally, we examined HERV-K envelope protein expression in prostate tumors by immunohistochemistry. HERV-K envelope protein was commonly upregulated in prostate tumors, but more so in tumors of African-American than European-American patients (61% versus 40%, P < 0.01). Examining HERV-K gag expression in peripheral blood mononuclear cells (PBMC) from 294 cases and 135 healthy men, we found that the abundance of HERV-K gag message was significantly higher in cases than controls and was associated with increased plasma interferon-γ. Men with gag expression in the highest quartile had >12-fold increased odds {odds ratio = 12.87 [95% confidence interval 6.3-26.25]} of being diagnosed with prostate cancer than those in the lowest quartile. Moreover, our results showed that HERV-K expression may perform better as a disease biomarker in older than younger men (whereas the sensitivity of prostate-specific antigen (PSA) testing decreases with age) and in men with a smoking history compared with never smokers. Combining non-invasive HERV-K testing with PSA testing may improve the efficacy of prostate cancer detection specifically among older men and smokers who tend to develop a more aggressive disease.


Assuntos
Adenocarcinoma/sangue , Produtos do Gene gag/sangue , Leucócitos Mononucleares/metabolismo , Neoplasias da Próstata/sangue , Fumar/sangue , Adenocarcinoma/diagnóstico , Adenocarcinoma/virologia , Quimiocina CXCL10/sangue , Retrovirus Endógenos/enzimologia , Expressão Gênica , Humanos , Interferon gama/sangue , Leucócitos Mononucleares/virologia , Masculino , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/virologia , RNA Mensageiro/sangue , RNA Mensageiro/genética , Fatores de Risco
16.
Appl Environ Microbiol ; 80(16): 5086-97, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24928873

RESUMO

Biological Mn oxidation is responsible for producing highly reactive and abundant Mn oxide phases in the environment that can mitigate metal contamination. However, little is known about Mn oxidation in low-pH environments, where metal contamination often is a problem as the result of mining activities. We isolated two Mn(II)-oxidizing bacteria (MOB) at pH 5.5 (Duganella isolate AB_14 and Albidiferax isolate TB-2) and nine strains at pH 7 from a former uranium mining site. Isolate TB-2 may contribute to Mn oxidation in the acidic Mn-rich subsoil, as a closely related clone represented 16% of the total community. All isolates oxidized Mn over a small pH range, and isolates from low-pH samples only oxidized Mn below pH 6. Two strains with different pH optima differed in their Fe requirements for Mn oxidation, suggesting that Mn oxidation by the strain found at neutral pH was linked to Fe oxidation. Isolates tolerated Ni, Cu, and Cd and produced Mn oxides with similarities to todorokite and birnessite, with the latter being present in subsurface layers where metal enrichment was associated with Mn oxides. This demonstrates that MOB can be involved in the formation of biogenic Mn oxides in both moderately acidic and neutral pH environments.


Assuntos
Bactérias/isolamento & purificação , Bactérias/metabolismo , Compostos de Manganês/metabolismo , Microbiologia do Solo , Urânio/metabolismo , Bactérias/classificação , Bactérias/genética , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Mineração , Dados de Sequência Molecular , Oxirredução , Filogenia , Solo/química
17.
Int J Neonatal Screen ; 10(1)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38535125

RESUMO

Hemoglobinopathies are the commonest monogenic disorder worldwide, with approximately seven percent of the world population being carriers of hemoglobinopathies. The healthcare utilization impact of thalassemia has resulted in global public health initiatives to screen for hemoglobinopathies, especially sickle cell disease (SCD). The Iowa Newborn Screening Program (INSP) has been in place for more than 50 years with a primary focus on detecting SCD. Recent changes in migration patterns have led to a global distribution of hemoglobinopathies in the western world, which has translated to an increase in the diagnosis of SCD and the incidental detection of non-sickling hemoglobinopathies within the INSP. This study documents the birth prevalence of hemoglobinopathies diagnosed in newborns through the INSP and highlights the need for newborn screening programs to evolve to meet the healthcare needs of underserved, minority populations.

18.
Microsc Microanal ; 19(3): 507-12, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23578755

RESUMO

Replication of chloroplast in plant cells is an essential process that requires co-assembly of the tubulin-like plastid division proteins FtsZ1 and FtsZ2 at mid-chloroplast to form a ring structure called the Z-ring. The Z-ring is stabilized via its interaction with the transmembrane protein ARC6 on the inner envelope membrane of chloroplasts. Plants lacking ARC6 are defective in plastid division and contain only one or two enlarged chloroplasts per cell with abnormal localization of FtsZ: instead of a single Z-ring, many short FtsZ filaments are distributed throughout the chloroplast. ARC6 is thought to be the anchoring point for FtsZ assemblies. To investigate the role of ARC6 in FtsZ anchoring, the mobility of green fluorescent protein-tagged FtsZ assemblies was assessed by single particle tracking in mutant plants lacking the ARC6 protein. Mean square displacement analysis showed that the mobility of FtsZ assemblies is to a large extent characterized by anomalous diffusion behavior (indicative of intermittent binding) and restricted diffusion suggesting that besides ARC6-mediated anchoring, an additional FtsZ-anchoring mechanism is present in chloroplasts.


Assuntos
Proteínas de Arabidopsis/metabolismo , Proteínas de Cloroplastos/metabolismo , Cloroplastos/fisiologia , Replicação do DNA , Arabidopsis , Genes Reporter , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Microscopia de Fluorescência , Ligação Proteica , Mapeamento de Interação de Proteínas , Coloração e Rotulagem/métodos
19.
Eur J Cell Biol ; 102(2): 151321, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37137199

RESUMO

The ability of cancer cells to finally overcome various lines of treatment in due course has always baffled the scientific community. Even with the most promising therapies, relapse is ultimately seen, and this resilience has proved to be a major hurdle in the management of cancer. Accumulating evidence now attributes this resilience to plasticity. Plasticity is the ability of cells to change their properties and is substantial as it helps in normal tissue regeneration or post-injury repair processes. It also helps in the overall maintenance of homeostasis. Unfortunately, this critical ability of cells, when activated incorrectly, can lead to numerous diseases, including cancer. Therefore, in this review, we focus on the plasticity aspect with an emphasis on cancer stem cells (CSCs). We discuss the various forms of plasticity that provide survival advantages to CSCs. Moreover, we explore various factors that affect plasticity. Furthermore, we provide the therapeutic implications of plasticity. Finally, we provide an insight into the future targeted therapies involving plasticity for better clinical outcomes.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Células-Tronco Neoplásicas
20.
Sci Rep ; 13(1): 20977, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017055

RESUMO

Qualitative observer-based and quantitative radiomics-based analyses of T1w contrast-enhanced magnetic resonance imaging (T1w-CE MRI) have both been shown to predict the outcomes of brain metastasis (BM) stereotactic radiosurgery (SRS). Comparison of these methods and interpretation of radiomics-based machine learning (ML) models remains limited. To address this need, we collected a dataset of n = 123 BMs from 99 patients including 12 clinical features, 107 pre-treatment T1w-CE MRI radiomic features, and BM post-SRS progression scores. A previously published outcome model using SRS dose prescription and five-way BM qualitative appearance scoring was evaluated. We found high qualitative scoring interobserver variability across five observers that negatively impacted the model's risk stratification. Radiomics-based ML models trained to replicate the qualitative scoring did so with high accuracy (bootstrap-corrected AUC = 0.84-0.94), but risk stratification using these replicated qualitative scores remained poor. Radiomics-based ML models trained to directly predict post-SRS progression offered enhanced risk stratification (Kaplan-Meier rank-sum p = 0.0003) compared to using qualitative appearance. The qualitative appearance scoring enabled interpretation of the progression radiomics-based ML model, with necrotic BMs and a subset of heterogeneous BMs predicted as being at high-risk of post-SRS progression, in agreement with current radiobiological understanding. Our study's results show that while radiomics-based SRS outcome models out-perform qualitative appearance analysis, qualitative appearance still provides critical insight into ML model operation.


Assuntos
Neoplasias Encefálicas , Radiocirurgia , Humanos , Radiocirurgia/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Imageamento por Ressonância Magnética/métodos , Aprendizado de Máquina , Variações Dependentes do Observador , Estudos Retrospectivos
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